JPH06348095A - Image forming device - Google Patents

Abstract

PURPOSE:To provide an image forming device which is constituted so that the various kinds of detection devices need not be incorporated, which is made inexpensive and miniaturized and which can obtain an optimum image. CONSTITUTION:The temperature condition and the humidity condition of an installing place, the thickness of an output paper, the type of the paper, the pattern information of the image which is formed or the like can be designated and inputted by a host device 22 and transmitted to a printer 21. At least one out of them is received by the printer 21 and an electrophotographic image forming process is changed according to the received condition by a printer control part 28. A user can send the information of an external condition, a using state or the like to the image forming device according to the using state and obtain the optimum image. Besides, the various kinds of detection devices need not be provided in the printer 21. Then, the printer 21 is made inexpensive and miniaturized. The thickness of the paper which is difficult to be technically detected can be easily judged by a human being. Besides, it is accurately judged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic system which is connected to an external device (for example, a host computer such as a personal computer, an office computer, a minicomputer, etc.) and outputs an image according to an instruction and image information from the external device. The present invention relates to an image forming apparatus.

[0002]

2. Description of the Related Art In a conventional image forming apparatus (printer),
Electrophotographic photoreceptors, developers, transfer materials, etc. are affected by the environmental conditions around the place where the printer is installed, and the sensitivity of the photoreceptor, the charge load of the developer, and the resistance value of the transfer material change. This will affect the image. Further, in a conventional electrophotographic printer, electrostatic transfer by means of a corona discharger, a bias applying roller, etc. is mainly used to transfer a toner image onto a transfer material. By the way, there are various types of transfer materials, and at the same time, the optimum transfer conditions differ depending on the environmental conditions of the printer and the like.

For this reason, the printer body has a temperature sensor, a humidity sensor, an environmental condition device, and a usage condition detection device such as the thickness and type of paper, and the electrophotographic image forming process changes depending on the condition detected by the device. I was letting it. Further, there is one in which a switch for inputting various conditions is provided in the printer main body, and the electrophotographic image forming process is changed by operating and inputting the switch.

Recently, as charging means provided in an electrophotographic printer or the like, (1) a low voltage power source can be achieved, (2) an extremely small amount of ozone is generated, and (3) a device configuration. Due to the advantages of simplicity and cost reduction, so-called contact charging means for directly charging the surface of an image bearing member has attracted attention. This is to bring a conductive member, to which a predetermined voltage is applied, into contact with the surface of the image carrier, and an oscillating voltage obtained by superimposing a constant-voltage-controlled DC bias on this conductive member and a constant-current-controlled light amount bias. A technique has been proposed in which the amount of electric charges applied from the conductive member to the surface of the image bearing member is always kept constant by applying a voltage, and the surface of the image bearing member can be uniformly charged in any environment.

Further, conventionally, a blade method, a roller method, a brush method and the like are known as cleaning means provided in an electrophotographic image forming apparatus or the like. The blade system is, for example, by pressing the edge portion of an elastic blade such as urethane rubber against the image carrier surface,
The residual toner adhering to the surface of the image carrier is forcibly peeled off. In the brush method, for example, a bias is applied to a conductive brush that is planted on the outer peripheral surface of a cylindrical body, and the brush is brought into contact with the surface of the image carrier while rotating, thereby adhering to the surface of the image carrier. Electrostatically remove residual toner,
It is mechanically removed.

[0006]

[Problems to be solved by the invention] However,
In the above-mentioned conventional example, some problems remain in the conventional contact charging means. (1) The constant current control of the AC bias applied to the conductive member is vulnerable to ambient noise. For example, in an electrophotographic printer using an AC bias as a bias applied to the developing means, these interfere with each other. There is a risk that the constant current control may malfunction. In addition, it can be said that it is in an extremely unstable state because it is easily affected by fluctuations in the electrostatic capacity of the image carrier with which the conductive member is in contact.

Further, in the case where there are pinholes or scratches on the surface of the image bearing member, when the conductive members come into contact with them, the charging current intensively flows from the conductive members to them, which causes a constant amount. The oscillating voltage applied to the conductive member may suddenly drop due to the current control, and so-called defective charging may occur. Therefore, the printer main body is provided with a temperature sensor, a humidity sensor, and an environmental condition detecting means, and the printer main body is provided with an environmental condition input switch, and the user operates and sets the switch to set the conductive member. Applying an AC bias suitable for the operating environment conditions at that time by constant voltage control that is relatively easy to control and that the applied voltage does not drop suddenly even if the contact charging means makes contact with a pinhole or the like. An electrophotographic printer configured to be used has also been proposed.

However, in the former case, each sensor and detection device are required, which increases the manufacturing cost. In addition, a place for installation is required inside the printer, and there is a certain amount of space for highly accurate detection, so it is a net for downsizing of the apparatus at present when the mainstream of the disposable is. In the latter case, the manufacturing cost, space, detection accuracy, and other problems described above are alleviated somewhat, but the user must go directly to the printer to set the conditions. If there is no network nearby because they are connected by a network, it is troublesome to go to the operation, and there are times when you can not actually get it. (2) The surface potential of the image carrier charged with the AC bias is a spatial wavelength λs determined by the frequency fo of the applied AC bias and the surface moving speed Vp of the image carrier.
It has p (Vp / fo), a so-called cycle mark, which is a charging spot.

Then, after line scanning is performed on the surface of the image carrier to expose n dots in the sub-scanning direction by turning on the laser, a space for m dots in the sub-scanning direction is also opened by turning off the laser. When the horizontal line pattern image is formed, the laser O
When the length L from FF to OFF and the spatial wavelength λsp become substantially equal to each other and the phases of both L and λsp coincide with each other, they interfere with each other and an interference fringe called so-called moire occurs.

This phenomenon is prominent when outputting a so-called graphic image in which the halftone area occupies most, but is hardly recognized when outputting a so-called text image in which most of the character area is closed. In order to prevent this, the frequency fo of the AC bias applied to the conductive member may be set as high as possible, but in this case, there are other problems such as charging noise and toner fusion. It becomes apparent.

All of these are caused by the vibration of the image carrier and the conductive member due to the vibration voltage applied to the conductive member. By setting the frequency of the AC bias as low as possible, it is possible to suppress the occurrence thereof. However, although it is relatively easy in the text image, the interference fringe becomes a problem in the graphic image as described above, and therefore the value cannot be easily lowered.

That is, in order to make a graphic image having a relatively low output frequency compatible with a text image having a high output frequency, the frequency of the AC bias applied to the conductive member must be set to a very limited value. There is a situation where it will not happen. (3) One of the image defects appearing on the output image is so-called fog, which is caused by the dark potential (white potential) Vd of the photosensitive drum surface charged by the charging roller and the bias applied to the developing device. There is a close correlation with the difference voltage Vd-Vdc with the DC component Vdc and the humidity. To the fog, the toner charged to the regular polarity adheres to the white background portion, the so-called background fog and the toner charged to the opposite polarity to the regular polarity adheres to the white background portion,
In order to prevent both so-called reversal fog, the ground fog, and the reversal fog in a mild environment from high humidity to low humidity, it is currently necessary to set the above-mentioned differential voltage to an extremely limited value. is there.

Further, when a sensor such as the thickness of the paper is provided, it is necessary to distinguish the difference of about 10 μm, which is technically difficult, and the detection mechanism becomes large and large in size, which causes a price increase. I was connected with one. Further, since the humidity sensor has poor responsiveness, it takes time to perform accurate detection, and measuring the humidity at power-on or during printing leads to a decrease in wait time or throughput, which is not preferable.

Furthermore, the cleaning means has a problem that it is easily affected by the surrounding environment, that is, temperature and humidity. For example, in the case of the blade method, since the repulsion elasticity of the cleaning blade is small and the loss coefficient is large at low temperatures, it becomes impossible to follow the minute irregularities on the surface of the image carrier, and cleaning failure easily occurs. Therefore, in order to prevent this, if the pressure contact force with respect to the surface of the image bearing member is increased and the residual toner is forcibly peeled off, a problem will occur at high temperature. That is, since the repulsion elasticity of the cleaning blade is large and the loss coefficient is small, so-called chattering occurs, and cleaning failure due to unpleasant sound or vibration is likely to occur.

In the case of the brush system, the resistance of the conductive brush is generally lowered at high humidity, and the conductive brush discharges the surface of the image carrier to deteriorate the photosensitive layer, or the image is deteriorated. The surface of the carrier is non-uniformly charged, and the residual toner once collected on the conductive brush is again attached to the non-uniformly charged portion, so that cleaning failure easily occurs. So to prevent this,
When the bias applied to the conductive brush is set to be low, the cleaning failure is likely to occur due to the fact that the electrostatic force against the residual toner on the surface of the image bearing member is reduced at low humidity.

That is, when the cleaning conditions are set so as to be adapted to the low temperature or the low humidity, it is possible to maintain the sufficient cleaning performance under all the environmental conditions such that the problem occurs at the high temperature or the high humidity. It was difficult.

[0017]

The present invention has been made for the purpose of solving the above-mentioned problems, and has the following constitution as one means for solving the above-mentioned problems. That is, receiving instructions and image signals from an external device connected,
In an electrophotographic image forming apparatus that prints an image, when an external device receives at least one of environmental conditions of an installation place and conditions of a recording medium, the electrophotographic image forming process is changed according to the conditions.

Further, in an electrophotographic image forming apparatus equipped with a charging means for printing an image in response to an instruction and an image signal from an external device connected thereto, the environmental condition and the output image when the device is used are output from the external device. When at least one of the pattern information is received, the bias condition applied to the charging means is changed according to the condition. Further, in an electrophotographic image forming apparatus including a transfer unit that prints an image in response to an instruction and an image signal from an external device connected to the external device, environmental conditions when the device is used, transfer material information, and an output image. When receiving at least one of the pattern information, the transfer condition of the transfer means is changed according to the condition.

Further, in an electrophotographic image forming apparatus which prints an image by receiving an instruction and an image signal from a connected external device, environmental conditions, output medium conditions and an output image pattern when the device is used from the external device. At least one of the information is received, and the transport condition of the output medium is changed according to the condition. In addition, in an electrophotographic image forming apparatus that prints an image by receiving an instruction and an image signal from an external device connected to the external device, environmental conditions, output medium conditions, and output image pattern information when the device is used are output from the external device. At least one of them is received, and the developing condition is changed according to the condition.

Further, in an electrophotographic image forming apparatus equipped with a cleaning means for cleaning an image carrier for receiving an instruction and an image signal from a connected external device and outputting an image, the environment when the external device is in use Upon receiving at least one of the conditions, the setting condition of the cleaning unit is changed according to the condition. Further, the cleaning means includes at least a rotatable roller, and when at least one environmental condition during use is received from an external device, the peripheral speed of the roller is changed according to the condition.

Further, the apparatus further comprises bias applying means for the cleaning means, and when the bias applying means receives at least one environmental condition during use from the external device, the bias applying means applies the cleaning means in accordance with the condition. Change the bias.

[0022]

With the above construction, the image forming apparatus does not require an external condition detecting device, and the cost is reduced. Further, since it is not necessary to install the detection device in the image forming apparatus, the space can be saved and the size of the apparatus can be reduced. Further, even if it is technically difficult to detect such as the thickness of the paper, it can be easily made by human judgment and the accuracy can be improved.

Further, since the setting can be made while the external apparatus is present, it is not necessary to go to the image forming apparatus placed at a distant place to set the condition, the operation is convenient, and the setting can be neglected. There is no such thing. Also,
The same effect as described above can be obtained by changing the bias condition applied to the charging unit or the transfer condition of the transfer unit.

Furthermore, by changing the setting conditions of the cleaning means for cleaning the image carrier, the same effect as described above can be obtained. Furthermore, the same effect as described above can be obtained by changing the bias applied by the bias applying means to the cleaning means. The present invention relates to an electrophotographic printer that prints an image in response to an instruction and an image signal from a host device, such as a temperature condition and a humidity condition at a place of installation from the host device, a thickness of a paper to be printed, and a type of paper. By receiving at least one of the pattern information of the image to be printed and changing the developing condition in the electrophotographic image forming process accordingly, the user can adjust the external condition and the use condition from the host device according to the use condition. Information such as status can be sent to the printer to obtain an optimum image.

Therefore, the external condition detecting device is not required and the cost is reduced. Further, since it is not necessary to install the detection device in the printer, it is not necessary to take a space for it and the device can be downsized. Further, even if it is technically difficult to detect such as the thickness of the paper, it can be easily made by human judgment and the accuracy can be improved. Also, since you can set it while you are on the host side, you do not have to go to the printer that you put away and set the condition.
The operation is convenient and there is no need to play with settings.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described in detail below with reference to the drawings. [First Embodiment] FIG. 1 is a view showing the arrangement of an electrophotographic printer which is an image forming apparatus according to a first embodiment of the present invention.

In FIG. 1, reference numeral 1 is an electrophotographic cartridge, which is constituted by integrating an electrophotographic photosensitive member 2, a charging roller 3, a developing device 4 and a cleaner 5. The electrophotographic photosensitive member 2 is made of OPC, amorphous Si, amorphous Si.
A photosensitive material such as is formed on a cylindrical base such as aluminum or nickel, and is generally referred to as a photosensitive drum (hereinafter referred to as "photosensitive drum").

First, the photosensitive drum 2 is uniformly charged by the charging roller 3. Next, laser scan 6
Then, the image signal is raster-scanned and exposed. The laser scanner 6 operates the blinking of the semiconductor laser with a polygon scanner to form an optical spot image on the photosensitive drum by the optical system and the folding mirror 7. As a result, an electrostatic latent image is formed on the photosensitive drum 2. The emission intensity and emission duty of the semiconductor laser of the laser scanner 6 are controlled by the exposure control unit 16. In addition, the main motor and scanner motor (not shown) are
Controlled by 8.

The electrostatic latent image formed on the photosensitive drum 2 is developed by the developing device 4. For the development, jumping development,
Two-component development, FEED development, etc. are used. Image exposure to erasing the electric charge of the latent image by irradiating the recording location with a laser,
Reversal development is often used in combination, in which toner is attached to the one with less charge. The image developed by the developing device 4 is transferred to a transfer material. The transfer material is stored in the cassette 8 and is fed one by one by the paper feed roller 9.

When a print signal is sent from the host device, paper is fed by the paper feed roller 9, and the transfer roller 11 is synchronized by the timing roller 10 with the image signal.
The toner image is transferred onto the transfer material. Transfer roller 11
Is made of an electrically conductive elastic material having a low hardness, and is a nip portion formed by the photosensitive drum 2 and the transfer roller 11, and electrostatically transferred by a bias electric field. The operation of the paper feed roller 9 and the timing roller 10 is performed by the paper feed control unit 2
Controlled by 0. The high-voltage controller 17 controls the bias applied to the charging roller 3, the bias applied to the developing device 4, and the bias applied to the transfer roller 11.

The transfer material on which the image has been transferred is fixed by the fixing device 12, sent by the paper discharge roller 13, and discharged to the paper discharge tray 14. On the other hand, the toner remaining after transfer is cleaned by the cleaner 5 by the blade. The fixing device 12
The pressing force and temperature of are controlled by the fixing controller 19. FIG. 2 is a diagram showing a connection state between the printer of this embodiment shown in FIG. 1 and the host device. In FIG. 2, 21 is the same as in FIG.
2 is a printer device using the electrophotographic system of this embodiment shown in FIG. 22 is a mini computer, workstation,
The host device is an external device such as a personal computer, and is connected to the printer 21 by a communication cable 23. The communication cable 23 exchanges various signals between the host device 22 and the printer device 21,
In addition to signals and image information related to the operation of the printer 21,
Environmental information, information about printer paper, etc. are also exchanged. In FIG. 2, one-to-one connection is made, but a plurality of host devices and a plurality of printers may be connected on the network. In this case, any host and printer combination may be made on the network. Can be operated by selecting.

FIG. 3 is a view showing the controller panel of the printer device displayed on the host device. From the controller panel, in addition to information 24 such as conventional paper size, paper feed direction, number of prints, magnification, font size, room temperature, room humidity, thickness of paper to be printed, envelope The type of paper such as OHP paper, label paper, cardboard, etc., whether the image to be printed emphasizes text such as characters and symbols, or whether gradation is important such as graphics and natural images. The information 25 necessary for obtaining a more preferable print can be set.

These items are not limited to the example shown in FIG. 3, and may be detailed as necessary. This is because, for example, the thickness and type of paper are technically difficult to detect automatically, but can be judged with high accuracy by human judgment. Further, by registering the physical properties of each brand of paper, it is possible to automatically specify the physical properties of the paper by designating the brand of paper. As a result, it is possible to make a simple and highly accurate setting.

In this embodiment, the selected one is marked with a double circle so that it can be seen at a glance. But,
This may be any display method, such as reverse display, as long as it can be easily discriminated. If these information 25 are not specified,
It is set to a predetermined default state. And
The control for performing this display and various information designated and input according to the display are sent from the host device 22 to the printer 21 according to a predetermined data format and control procedure. Since this control is closely related to the printer, this processing routine in the host device 22 is supplied from the printer maker as a printer driver OS, and the user, the host maker, or the application maker sends the system O to the system O.
It is desirable to be used by being incorporated into S or incorporated into an application.

FIG. 1 mainly shows the mechanical portion of the printer 21 of the present embodiment, but FIG. 4 shows the block configuration of the operation control portion of the printer 21 that drives and controls each ward in FIG.
Image data and the printer control information code shown in FIG. 3 are sent from the host device 22 to the printer 21 through the communication cable 23. The printer 21 sends and receives various signals to and from the host device 22 via the interface 26. The image data received via the interface 26 is sent to the image expansion unit 27, where it is converted into raster data. Further, commands relating to printer control are sent to the printer control unit 28.

The printer controller 28 includes an exposure controller 16,
A high voltage controller 17, a motor controller 18, a fixing controller 19,
It controls each of the paper feed control units 20. Exposure control unit 1
In 6, the image data raster-converted by the image developing unit 27 is converted into blinking of the semiconductor laser based on the sequence controlled by the printer control unit 28, and the electrophotographic photosensitive member 2 is irradiated with the image data.

The semiconductor laser 29 is a known APC (Automatic Power) provided in the exposure controller 16.
er control) means to maintain a constant emission intensity. In addition, in this embodiment,
A correction value preset in the exposure controller 16 based on the information 25 from the host device 22 so that a constant electrostatic latent image is formed even if the sensitivity of the electrophotographic photosensitive member 2 changes with temperature and humidity. Accordingly, the emission intensity or emission duty ratio of the semiconductor laser 29 is changed.

The bias applied to the charging roller 3, the bias applied to the developing device 4, and the bias applied to the transfer roller 11 are
It is controlled by the high voltage controller 17. These are also corrected based on the information 25 from the host device 22. For example, the charging potential of the electrophotographic photosensitive member 2 changes depending on temperature and humidity, and the charging amount of the toner also changes. Therefore, the bias applied to the charging roller 3 and the developing unit 4 are adjusted to a preset correction value. The applied bias is corrected and applied. Since the optimum transfer condition varies depending on the type of paper and the thickness / humidity, this is also corrected.

Main motor 30 and scan motor 31
Are controlled by the motor controller 18. Fixer 12
The pressing force and temperature of are controlled by the fixing controller 19. When the temperature of the fixing device 12 is low, the fixing property deteriorates,
When the humidity is high, the recording paper tends to curl, and the fixing property varies depending on the thickness of the paper. To prevent these
In this embodiment, the pressure and the temperature are changed to deal with this. Further, since the envelopes are overlapped with each other, a high pressure causes them to slip and become wrinkled. Therefore, the applied pressure is lowered and the temperature is increased by that amount to control the fixing property.

The operation of the paper feed roller 9 and the timing roller 10 is performed by controlling the paper feed clutch 33 by the paper feed controller 20. The printer control unit 28 also corrects and controls the operation by a feed back from sensors 34 such as a paper size sensor, a registration sensor, a paper discharge sensor, and a toner remaining amount sensor.

FIG. 5 shows the detailed construction of the printer control unit 28. The operation program and data of the entire device are the main RO
It is stored in M36. A correction program and correction data for change information of external conditions are stored in the sub ROM 37. These programs and data are stored in the CPU 3
The operation is controlled by 5. The information 25 from the host device 22 is input from the interface 26 shown in FIG. 4 to the CPU 35 via the I / O port 39, and the information 25
And the result of performing the correction calculation process based on it is RA
It is stored in M38.

The information and the calculation result stored in the RAM 38 are held until the information is updated or the power is reset. The feedback back information and calculation results from the sensors are retained until the information is updated or the power supply is reset. Feed back information from the sensors is transmitted to the CPU 35 via the I / O port 39, and control of each part is transmitted from the CPU 35 to each control unit via the I / O port 39.

FIG. 6 shows a control flow chart for correcting the laser emission intensity of the semiconductor laser 29 by the exposure controller 16 as an example of the electrophotographic image forming process correction based on the correction information from the host device 22. The exposure controller 16 first determines in step S1 whether or not there is information from the host device 22. When there is no information from the host device 22, the process proceeds to step S2, and the emission intensity of the laser is controlled to the default value.

On the other hand, when there is information from the host device 22, the process proceeds to step S3 to check whether the room temperature information in the information is high temperature, normal temperature or low temperature. If the temperature is high, the process proceeds to step S4, and the sensitivity of the electrophotographic photosensitive member becomes high (fast), so the emission intensity is corrected to "-2". Then, the process proceeds to step S7. On the other hand, when the room temperature information is normal, the process proceeds to step S5, the light emission intensity is controlled not to be corrected, and the process proceeds to step S7. If the room temperature information is low, the process proceeds to step S6, and the sensitivity of the photoconductor becomes low (slow).
Correct the emission intensity to be "+2". Then, the process proceeds to step S7.

Then, in step S7, the control data is controlled so as to be added with the correction value according to the correction values in steps S4 to S6. Then, in step S8, it is checked whether the humidity information in the information from the host device 22 is high humidity, normal humidity or low humidity. If the humidity information is high humidity, step S
In step 9, the sensitivity of the electrophotographic photosensitive member is increased, so the emission intensity is corrected by "-1". Then, the process proceeds to step S12.

On the other hand, if the humidity information is normal, the process proceeds to step S10, and the process proceeds to step S12 without any correction.
Further, when the humidity information is low humidity, the sensitivity becomes slow, so the emission intensity is corrected by "+1". Then, the process proceeds to step S12. In step S12, steps S9 to S
The correction value in 11 is added to the control data. Next, in step S13, the emission intensity of the laser is controlled by the correction data obtained by adding the correction value.

As described above, according to the present embodiment, the printer 21 does not require an external condition detecting device, and the cost is reduced. Further, since it is not necessary to install a detection device in the printer 21, space is saved and the device can be downsized. Further, even if it is technically difficult to detect such as the thickness of the paper, it can be easily made by human judgment and the accuracy can be improved.

Further, since the operation setting for the printer 21 can be made while the host device 22 is present, it is not necessary to go to the device which is placed at a remote place, and the condition setting is not necessary, and the operation is convenient and the setting is possible. There is no such thing as water. [Second Embodiment] FIG. 7 is a diagram showing a printer control panel on the host side in a second embodiment according to the present invention. In FIG. 7, compared with the printer control panel shown in FIG. 3 of the above-described first embodiment, a setting item as to whether or not to hold the setting state shown in a is added.

In the second embodiment, the printer 21 fetches the instruction information for holding the setting state, and when the setting state is "hold", various settings sent from the host device 22. The information is controlled so as to be held in the RAM in the printer 23. The RAM used here is preferably a non-volatile RAM. If the user chooses to keep the settings, the information is stored in RAM even when the printer is turned off.
This is because it is held inside.

First, it is checked whether or not there is information from the host device 22, and if there is no information, it is not immediately controlled by the default value, but whether or not there is further held setting information is checked and set. When the information is held, the control is performed so as to control the held information value. Since the other configurations and controls are the same as those in the above-described embodiment, detailed description will be omitted. When the set state is not retained, this set state is reset by power-off and returns to the default state.

By controlling as described above, it is possible to save the trouble of re-setting every time, which is convenient in the case where the power is turned off and on many times. On the contrary, when the power is left on for a long time or is used by multiple people,
Since the usage status changes, it is easier to use without maintaining the setting status. These can be set according to the preference of the user, so it can be adapted to the individual circumstances of the user.

[Third Embodiment] FIG. 8 is a diagram showing an example of a printer control panel on the host device 22 side in the third embodiment of the present invention. In FIG. 8, as compared with the printer control panel shown in FIG. 7 of the above-described second embodiment, a setting item as to whether or not the setting is taken in from the printer shown in b is added.

Then, in the third embodiment, according to the control of the above-described embodiment, the state preset in the printer 21 is controlled so that it can be taken in by the host side.
It should be noted that the interface between the host device and the printer used in the third embodiment is not a one-way interface such as a so-called Centronics interface, but a bidirectional Centronics interface, which is an improved version of this interface, RS232C specification, RS422 specification, SC
Any interface can be used as long as it is a bidirectional interface such as SI specification and GPIB specification. Other hardware configurations may be similar to those of the above-described embodiment.

The flow chart of FIG. 9 shows the control when the host side fetches the state set in the printer in the third embodiment. First, in step S14, it is monitored whether the setting fetch from the printer 21 is designated. If the setting import is specified, step S
Proceed to step 15 to check the connection between the host device and the printer. If the connection is not established, the process proceeds to step S16 and the fact is displayed on the host device 22.

If the printer 21 is normally connected, the process proceeds to step S17 to instruct the printer 21 to send the setting information and fetch the setting data sent from the printer 21 to the printer. And finally step S
At 18, the controller panel is controlled so as to possess it in accordance with the taken data, and the corresponding data is rewritten.

By the above control, when the host device 22 is reset for some reason, when setting is made from one host on the network, and when another host is connected, the setting is newly made. Easy to set up without having to re-insert. As described above, according to the above-described first to third embodiments, in the electrophotographic printer that receives an instruction and an image signal from the host device and prints an image, the temperature of the installation place is different from the host device. By receiving at least one of the conditions, humidity conditions, thickness of paper to be printed, paper type, pattern information of images to be printed, etc., and changing the electrophotographic image forming process accordingly, the user can change the usage status. In addition, the host device can send information such as external conditions and usage conditions to the printer to obtain an optimum image.

Therefore, the cost of the external enemy detection device is reduced because the external enemy detection device is unnecessary. Further, since it is not necessary to install the detection device in the printer, it is not necessary to occupy a space for it and the device can be downsized. Further, even if it is technically difficult to detect such as the thickness of the paper, it can be easily made by human judgment and the accuracy can be improved. Also, since the settings can be made from the host side, there is no need to go to a printer located at a distant place and set the conditions, the operation is convenient, and the settings are not neglected.

Further, since it is possible to select to hold the setting state or to take in the state set in the printer to the host device, it is possible to set according to the circumstances of each user. [Fourth Embodiment] In the above description, the indoor temperature and indoor humidity settings are set to "low", "normal",
Although the three modes of “high” have been set, the present invention is not limited to the above example, and may be set as a specific numerical value. Finer control is possible when set as a specific numerical value. A fourth embodiment according to the present invention configured to specify the room temperature and humidity with specific numerical values will be described below.

FIG. 10 is a diagram showing an example of a control panel of the printer device 21 in the fourth embodiment, in which specific temperature and humidity can be designated and input as an area 25 for detailed setting. The other basic configurations of the fourth embodiment are similar to those of the above-described embodiments, and the configurations shown in FIGS. 1, 2, 4, and 5 can be employed. And, in the fourth embodiment, the semiconductor laser 2 shown in FIG.
The control of the semiconductor laser 27 in the fourth embodiment will be described below. As described above, the semiconductor laser 27 is the known APC (Automatic Power Control).
Although the light emission intensity is kept constant by the means l), the sensitivity of the electrophotographic photosensitive member 2 changes with temperature and humidity, so that the surface potential obtained is not constant with a constant emission intensity.

For example, in the case where the electrophotographic photosensitive member 2 is an OPC photosensitive member, as the temperature rises, the occurrence of free carriers increases, so that both the dark portion potential V _D and the light portion potential _VL decrease as shown in FIG. Originally, the surface potential of the OPC photosensitive member is a negative potential, but in the following description, the negative sign will be used for the sake of simplicity. Indoor temperature 20 ° C, humidity 60% Rh
When the exposure amount is set so that the standard potential of 150 V is obtained at the time of, the bright part potential V _L and the temperature T
The relationship of is

[0061]

## EQU1 ## V _L = 150-1.31 × (T-20) (Equation 1) Further, when the humidity is high, electric conductivity due to water is generated, and therefore, as shown in FIG. 12, the dark part potential V _D ,
Both the light portion potential V _L decrease. From the result obtained in the experiment, when the relation between the light potential V _L and the humidity H is linearly approximated,

[0062]

## EQU00002 ## V _L = 150-0.84 × (H-60) (Expression 2) It is the difference between V _L and V _DC that contributes to the reproduction of image density and line width in reversal development. Therefore, in the fourth embodiment, in order to keep this constant, the emission intensity of the semiconductor laser is changed based on the information 25 from the host device 22.

FIG. 13 shows the room temperature of 20 ° C. and the humidity of 60% Rh.
The relationship between the exposure amount E and the bright portion potential _VL at the time of is shown. If this is also a linear approximation,

[0064]

V _L = 150-27.5 × (E-3) (Equation 3)
Can be expressed as From this, if the bright portion potential V _{L under} a certain condition is known, the exposure amount E for setting it to 150 V can be obtained. This is shown below.

[0065]

## EQU00004 ## E = 3 + (150-V _L ) ÷ 27.5 (Equation 4) Therefore, in order to keep the light portion potential V _L at a constant value of 150 V, the light portion potential is calculated from the room temperature and humidity at that time. Then, the required exposure amount may be calculated. For example, room temperature is 30 ° C and humidity is 8
In the case of 0%,

[0066]

## EQU5 ## The change with room temperature is ΔV _L = -1.31 × (3
0-20) = - change by 13.1V humidity, ΔV _L = -0.84 × (80-6
0) = − 16.8 V Therefore, E = 3 + (− 13.1−16.8) ÷ 27.5 = 1.92 μJ / cm ² (Equation 5) The exposure amount and the emission intensity are proportional to each other by the optical constants. Therefore, the emission intensity for keeping the bright portion potential constant is required.

FIG. 14 shows control of correction of laser emission intensity in the fourth embodiment. First, in step S21, it is checked whether there is information from the host. If there is no information from the host, the process proceeds to step S22, and the default temperature of 20 ° C. and humidity of 60% is designated. And step S24
Proceed to. On the other hand, if there is information from the host, step S2
Proceed to step 3 and input the temperature and humidity specified by the host.
Then, the process proceeds to step S24.

At step S24, the designated data at step S22 or the input data at step S23 is stored in the RAM 38 shown in FIG. Then, in step S25, the change in V _L with temperature is calculated based on the above-mentioned (Equation 1). Similarly, in step S26, the change in V _L due to humidity is calculated based on (Equation 2). In step S27, the exposure amount for setting V _L to 150 V is calculated based on (Equation 3).

The calculation result thus obtained is stored in the RAM 38 in step S28. The exposure controller 16 changes the laser emission intensity by APC based on the calculation result in step S29. As described above, according to the fourth embodiment, more detailed temperature and humidity settings can be set,
More precise control is possible.

[Fifth Embodiment] In the fifth embodiment, as shown in FIG. 15, in the detailed setting 25 from the host, it is possible to specify whether the image is text-based or graphic-based. FIG. 15 shows an example in which the image is set to be mainly text. For example, in the case of a text-based image, an image in which the image has a high contrast and a thick-colored image is preferable, and in the case of a graphic-based image, an image with gradation and a slightly low contrast is preferred. Therefore, in the fifth embodiment, the emission duty of the semiconductor laser is changed to deal with them.

FIG. 16 shows the lighting control of the semiconductor laser 29 in the fifth embodiment in the text mode and the graphic mode. In FIG. 16, 1 dot lighting, 1 dot lighting, 2 dot lighting, 1 dot lighting,
The lighting control timing in each mode when the light is turned off for 5 dots is shown. In the text mode, the semiconductor laser 29 is normally turned on according to the image signal. On the other hand, in the graphic mode, the image signal is lit with a delay. As a result, even if the lighting ratio of the image signal is increased, since the lighting is delayed, the density does not rise suddenly and a gradation can be obtained.

FIG. 17 is a diagram showing the relationship between the lighting ratio of the image signal shown in FIG. 16 and the image density. According to the fifth embodiment, as shown in FIG. 17, in the text mode, the density is Although it starts up immediately, it does not rise suddenly in the graphic mode, so the gradation is improved. FIG. 18 shows an example of a control circuit that delays the above image signals. In FIG. 18, the operation delay time of the IC circuit (for example, TTL circuit) is used to delay the image signal. The image signal VDO is also guided to the delay IC 41 together with the AND gate 40. Whether to bypass the delay IC depends on whether the switch 42 is closed.

When the switch 42 is closed in the text mode or the like, the image signal is not modulated and the semiconductor laser 29 is turned on at the same timing. On the other hand, when the switch 42 is open, the lighting time of the image signal is delayed due to the delay caused by passing through the delay IC. The opening and closing of the switch 42 is performed according to the designation from the host computer.

As described above, according to the fifth embodiment, it is possible to obtain an optimum image even if the printer cannot discriminate such as text and graphics. [Sixth Embodiment] FIG. 14 is a view showing the arrangement of a printer according to the sixth embodiment of the present invention. In the sixth embodiment, an LED array 43 is used instead of the semiconductor laser 29 as the exposure light source in the printer shown in FIG.

Since the LED array 43 is easily affected by the light emission intensity due to heat, in addition to the correction of the temperature and humidity of the electrophotographic photosensitive member 2 as in the above-described embodiments, the temperature and the light emission intensity of the array can be controlled. Becomes important. Since the temperature of the array is influenced by the environment in which it is placed, the lighting current of the LEDs of the array is changed by receiving the temperature information of the environment in which it is placed from the host. The correction of the lighting current may be performed based on the data of the current vs. emission intensity for each temperature of the LEDs of the array. By controlling in this way, the light emission intensity of the array can be kept substantially constant.

As in the sixth embodiment, the semiconductor laser 29 is used as the exposure light source in the printer, and the LED array 4 is used.
By using 3, it is possible to further reduce the cost. [Seventh Embodiment] According to the present invention, the electrophotographic image forming process is controlled by changing the bias condition of the charging means, not by controlling the light emitting condition of the semiconductor laser during the electrophotographic image formation. The seventh embodiment will be described below.

In the seventh embodiment, the schematic structure of each part is the same as that of the above-mentioned first embodiment, for example, but the bias condition applied to each charging means controlled by the high voltage controller 17 is different. Hereinafter, in the seventh embodiment, the user sets the environmental conditions for using the printer 21 via the host 22 to the printer 2.
A method of correcting the voltage of the AC component of the bias applied to the charging roller 3 by instructing No. 1 will be described.

Prior to the above description, the difference in the charging characteristics depending on the operating environment conditions of the charging roller 3 will be described first. The material used for the charging roller 3 is generally
The impedance changes, and the appropriate range of the applied voltage for uniformly charging the surface of the photosensitive drum 2 changes. That is, even if the applied voltage is an appropriate value in a room temperature and normal humidity environment, the impedance of the charging roller 3 increases in a low temperature and low humidity environment, and the partial pressure of the charging roller 3 increases. Substantially, the partial pressure of the AC component of the bias applied to the photosensitive drum 2 is lowered, and a partial charging failure called sand is caused. On the contrary, in a high-temperature and high-humidity environment, the impedance of the charging roller 3 becomes low, so that a high voltage is directly applied to the photosensitive drum 2 and a charging current leak occurs.

FIG. 20 shows the humidity dependence of the appropriate voltage of the AC component of the bias applied to the charging roller 3, and FIG. 21 shows this temperature dependence. As shown in FIGS. 20 and 21, it can be seen that the impedance change of the charging roller 3 is more affected by the humidity change than the temperature change. Therefore, in the seventh embodiment, the user instructs the printer 21 to use the environmental conditions of the printer 21 via the host 22, and applies a proper bias to the charging roller 3 under the environmental conditions, whereby the photosensitive drum 2 The surface can be uniformly charged.

The user uses the printer 22 via the host 22.
The printer 21 is instructed about the operating environment conditions of the charging roller 3
The control for controlling the voltage of the AC component of the bias applied to is substantially the same as the flow chart shown in FIG. 6 in the above-described first embodiment. However, in the seventh embodiment, the default value in step S2 is the default value of the voltage of the AC component of the bias applied to the charging roller 3, and constant voltage control is performed so that it becomes 2200 Vpp.

In step S4 in which the room temperature is high, the voltage of the AC component of the bias applied to the charging roller 3 is corrected by -1 in order to prevent the charging current from leaking due to the impedance of the charging roller 3 becoming low. In step S6, which is a case where the room temperature is low, the voltage of the AC component of the bias applied to the charging roller 3 is corrected by +1 in order to prevent the charging failure due to the high impedance of the charging roller 3.

Similarly, seeing whether the humidity is high humidity, normal humidity or low humidity,
In step S9, which is a case of high humidity, the voltage of the AC component of the bias applied to the charging roller 3 is corrected in order to prevent the charging current leak due to the impedance of the charging roller 3 becoming low. Since the influence is larger than that, -2 correction is performed. Step S for low humidity
In No. 11, the voltage of the AC component of the bias applied to the charging roller 3 is corrected in order to prevent the charging failure due to the increase in the impedance of the charging roller 3, but as described above, the influence is larger than the temperature, so +2. to correct.

Next, in step S13, the voltage of the AC component of the bias applied to the charging roller 3 is controlled to a constant voltage by the correction data obtained by adding the correction value. As described above, in the seventh embodiment, the constant voltage value of the AC component of the bias applied to the charging roller 3 is +200 Vpp for the correction value +1 and -200 Vpp for the correction value -1 and the default value 220.
Vary from 0 Vpp.

As described above, according to the seventh embodiment, the user instructs the printer 21 via the host 22 on the environmental conditions of use of the printer 21, and the voltage of the AC component of the bias applied to the charging roller 3 is set. By performing the correction, the user can send information such as external conditions and usage status to the printer from the host device according to the usage status to obtain an optimum image.

[Eighth Embodiment] In the seventh embodiment described above, the bias condition applied to the charging means is changed by correcting the voltage of the AC component of the bias applied to the charging roller 3, but the present invention is not limited to this. The present invention is not limited to the above example, and the bias condition may be changed by correcting the frequency of the AC component of the bias applied to the charging roller 3.
As described above, the eighth embodiment of the present invention in which the user instructs the printer via the host of the image information to be output and corrects the frequency of the AC component of the bias applied to the charging roller 3 will be described below. .

First, the relationship between the frequency of the AC component of the bias applied to the charging roller 3 and moire, charging noise, and fusion will be described. The configuration of the printer 21 in the eighth embodiment is almost the same as that of the above-described embodiment, but more specifically, the printing density (resolution) of the printer 21 in this embodiment is 600 dpi, and the photosensitive drum 2 has a predetermined size. It is rotationally driven at a peripheral speed (process speed) of 50 mm / sec. Here, (1) the frequency of the AC component of the bias applied to the charging roller 3 is fo (Hz), (2) the peripheral speed of the photosensitive drum 2 is Vp (mm / sec), and (3) the line scanning print density (resolution). ) Is D (dpi) (4) The line width of the line scanning is n (dot) (5) The gap between the lines is m (space) (6) The diameter of one dot is D (= 25.4 / D) (7) The line pitch is L {= (n + m) × d} (8) When the spatial frequency of the line pitch is fs (= Vp / L), the frequency fo and the spatial frequency fs of the line pitch overlap each other, and the following equation ( Moire will occur if it is in the relationship represented by the equation (6).

[0087]

Fs = Vp / L = Vp / {(n + m) × d} = Vp × D / {(n + m) × 25.4} = fo (6) The line pitch (L (mm)) shown by the equation 6 22 shows the relationship between the line pitch spatial frequency fs (Hz).
As can be seen from FIG. 22, the spatial frequency fs is

[0088]

Equation 7] n (dot): m (space ) = 1: it becomes maximum when 1, the spatial frequency fs in this case is fs ₁ =
It becomes 591 (Hz). Therefore, the frequency fo of the AC component of the bias applied to the charging roller 3 is set to be higher than the spatial frequency fs _{1 of the line} pitch, for example, 600.
When set to Hz, it is possible to prevent moire from occurring in the printer 21 having a print density of 600 dpi.

However, when the frequency of the AC component of the bias applied to the charging roller 3 is set as high as 600 Hz in this way, the charging roller 3 hits the surface of the photosensitive drum 2 more frequently, so that the charging noise is large and the toner melts. The problem becomes apparent when it becomes easy for wear to occur. Therefore, in order to suppress these occurrences, it is necessary to set the frequency as low as possible.

However, if it is too low, uneven charging occurs on the surface of the photosensitive drum 2. Due to this uneven charging, extra toner is attached to the non-image portion on the surface of the photosensitive drum 2 and uneven charging occurs on the output image. Black stripe image defects occur. Therefore, when the minimum charging frequency that does not cause the uneven charging in the so-called text image is determined, it is 150 Hz in the printer 21 of the present embodiment.

In the conventional printer, an AC bias having a constant frequency is always applied to the charging roller regardless of the pattern of the output image. That is, even in a text image other than a graphic image, a high frequency is set so that moire does not always occur, and an irritating charging sound is always generated during image formation. Therefore, the frequency of the AC component of the bias applied to the charging roller 3 is set to be high only when a graphic image having a relatively low output frequency and in which moire is easily generated is output, and a text in which the output frequency is relatively high and moire does not occur is set. When outputting an image, this should be set as low as possible.

In FIG. 23, the user sends the image information to be output in the eighth embodiment to the printer 2 via the host 22.
1 shows a flow chart for controlling the frequency of the AC component of the bias applied to the charging roller 3. In FIG. 23, first, in step S31, it is determined whether or not there is information from the host 22. When there is no information from the host 22, it is determined that a text image is to be output and the process proceeds to step S33 so that the frequency of the AC component of the bias applied to the charging roller 3 becomes the default value (150 Hz in this embodiment). Control.

If there is information from the host 22 in step S31, the flow advances to step S32 to check if it is a text image or a graphic image. If the information is to output a text image, the process proceeds to step S33, where the frequency of the AC voltage applied to the charging roller 3 is the default value (15).
0 Hz). On the other hand, step S32
If the information is to output a graphic image as an image, the process proceeds to step S34, and the frequency of the AC component of the bias applied to the charging roller 3 is controlled to be 600 Hz in order to prevent the occurrence of moire.

According to the eighth embodiment described above, by instructing the printer via the host of the image information to be output by the user, the frequency of the AC component of the bias applied to the charging roller 3 is corrected. The user can send information such as the usage status from the host device to the printer according to the usage status to obtain an optimum image. [Ninth Embodiment] In a ninth embodiment, a method will be described in which the user instructs the printer 2 through the host on the environmental conditions of the printer to correct the voltage of the DC component of the bias applied to the charging roller. First, it appears in the voltage of the DC component of the bias applied to the charging roller and the output image,
The relationship with so-called fog will be described.

The fog is caused by the dark potential (white background potential) Vd of the surface of the photosensitive drum 2 charged by the charging roller 3.
And the voltage V of the DC component of the bias applied to the developing device 4.
There is a close correlation with the difference voltage Vd-Vdc with respect to dc. To the fog, the toner charged to the regular polarity adheres to the white background portion, so-called background fog, and the toner charged to the opposite polarity to the regular polarity adheres to the white background portion. There is so-called reversal fog, which is the ninth aspect of the present invention.
When the proper difference voltage range in which these are not generated was obtained using the printer 21 in the example, it was found that there was a difference depending on the humidity as shown in FIG.

The printer 21 in the ninth embodiment is
The light potential (black background potential) V1 on the surface of the photosensitive drum 2 and the voltage Vdc of the DC component of the bias applied to the developing device 4.
Are set to -150v and -500v as standard values, respectively. Further, even if the voltage of the DC component of the bias applied to the charging roller 3 is set so that the difference voltage is 110 V so that neither ground fogging nor reversal fogging occurs in a low humidity environment, in a high humidity environment Ground fog will occur.

In consideration of the above points, in the ninth embodiment, the humidity information of the environment in which the printer 21 is used is instructed to the printer 21 via the host, and the voltage of the DC component of the bias applied to the charging roller 3 is indicated. It is possible to prevent such a problem by changing. Figure 25
A flow chart for controlling the voltage of the DC component of the bias applied to the charging roller 3 by instructing the printer 21 via the host of the humidity information of the environment in which the printer 21 is used in the ninth embodiment of the present invention. Indicates.

In FIG. 25, first, in step S41, it is determined whether or not there is humidity information from the host 22. When there is no humidity information from the host 22, step S43
Then, the voltage of the DC component of the bias applied to the charging roller 3 is controlled so that the differential voltage becomes the default value 140v. In the ninth embodiment, the voltage of the bias DC component is controlled to -640v.

On the other hand, if there is humidity information from the host 22 in step S41, the process proceeds to step S42 to check if the humidity is high humidity, normal humidity or low humidity. Normally, step S
43, the voltage of the bias DC component applied to the charging roller 3 is adjusted so that the differential voltage becomes the default value 140v (the bias DC component voltage is -640v.
To) control.

On the other hand, if the humidity is high in step S42, the process proceeds to step S44, in which the voltage of the DC component of the bias applied to the charging roller 3 in order to prevent the occurrence of background fog,
The difference voltage is controlled to be 180v. In the ninth embodiment, the voltage of the DC component of the bias is -68.
Control to 0v. If the humidity is low in step S42, the process proceeds to step S45, and the voltage of the DC component of the bias applied to the charging roller 3 in order to prevent the occurrence of reversal fog is controlled so that the difference voltage becomes 110v. In the ninth embodiment, the voltage of the DC component of the bias is controlled to -610v.

In the ninth embodiment described above, the case has been described in which the voltage Vdc of the DC component of the bias applied to the developing device 4 is fixed. However, for example, in the case of changing this as the image density adjusting means. Needless to say, this can be applied by changing the voltage of the DC component of the bias applied to the charging roller 3 in conjunction with this.

As described above, in the electrophotographic printer having the charging means for receiving the instruction and the image signal from the host device and outputting the image, the temperature condition and the humidity condition when the printer is used from the host device, By receiving at least one of the pattern information and the like of the output image and changing the bias condition applied to the charging means in accordance with it, the user can change the bias condition applied from the host device to the external condition, Information such as usage status can be sent to the printer to obtain an optimum image.

Therefore, the external condition detecting device is not required, and the cost is increased. Further, since it is not necessary to install the detection device inside the printer, it is not necessary to take a space for it and the device can be downsized. Also, since the settings can be made while staying on the host side, it is not necessary to go to a printer placed at a distant place to set conditions, scanning is convenient, and there is no need to worry about settings.

Further, since it is possible to select to hold the setting state or to take in the state set in the printer to the host device, the setting can be made according to the individual circumstances of the user. Although the printer including the contact charging unit has been described in detail, it goes without saying that the printer including the corona charging unit has the same effect. [Tenth Embodiment] In the above description, as one means for changing the electrophotographic process conditions, an example of changing and controlling the bias conditions of the charging means has been described, but the present invention is limited to the above examples. Alternatively, the transfer conditions of the transfer means may be controlled to obtain an optimum image. A tenth embodiment according to the present invention which is controlled in this way will be described below.

Also in the tenth embodiment, the schematic construction of each part is the same as that of the above-mentioned first embodiment, for example, but the transfer conditions for the transfer means by the high voltage controller 17 are different. First, the printer user uses the printer 21 on the host 22.
The print mode is selected for, and the control panel shown in FIG. 26 is displayed. This panel differs from the above-described first embodiment shown in FIG. 3 in that the detail setting area 25 can be set to distinguish between the 1st and 2nd side prints of the print environment information.

These signals are transmitted through the path 23 of the block diagram shown in FIG. 2 and reach the interface unit 26 in the printer shown in FIG. Here, the image data is sent to the image expansion unit 27, and the printer environment information is sent to the printer control unit 28.
Are transmitted separately. In the tenth embodiment,
The printer controller 28 selects an optimum transfer voltage based on the obtained printer environment information, drives the high voltage controller 17 and controls the transfer roller 11 at a constant voltage. At this time, the optimum transfer voltage is determined according to each environmental information as follows. The optimum transfer voltage determination control based on each environmental information in the tenth embodiment will be described below with reference to the flow chart of FIG.

First, the transfer bias value corresponding to the resistance value of the transfer material and the resistance value of the transfer roller is determined from the temperature and humidity information. In the tenth embodiment, regarding the resistance value of the transfer roller, T. V. C. Control (Automatic Transfer
Since voltage control) is adopted, setting is not performed depending on temperature and humidity conditions. A. T. V. C. In the control, the transfer roller is subjected to constant current control with respect to the non-sheet passing, in particular, the photosensitive member rotating surface which is normally charged, and the resistance value of the transfer roller is detected from the magnitude of the voltage generated at that time. The resistance value of the transfer material is set based on the humidity and the type and thickness of the transfer material.

As shown in FIG. 26, the humidity setting is divided into three steps: [humidity; low temperature (50% or less), normal (5
0 to 70%), high humidity (70% or more)], and 5 types of paper types (non-passable paper, recycled paper, OHP, label paper,
Envelopes) and thickness can be selected in 3 levels (thin, normal, thick). The optimum transfer bias setting method according to each environmental information in the tenth embodiment is performed as follows.

First, when the print signal In is received at step S51, at the time of pre-rotation immediately before printing, step S5 is performed.
2 for detecting the transfer roller resistance described above. T.
V. C. Take control. A. at this time T. V. C. The control is a constant current control of 1.5 μA, and the generated voltage V
_O is detected. The value of 1.5 μA is a value that does not leave a positive charge (in the tenth embodiment, the reversal development method using negative toner is adopted) on the photosensitive drum.
Then, in step S53, a predetermined V _P determined by the control to be described later is added to {V _T (transfer voltage) = V _O + V _P }
_T (transfer voltage) is determined, and the transfer voltage during printing is controlled to a constant voltage by V _T (transfer voltage) determined in the subsequent step S54. However, V _P is a voltage set according to information from the host and will be referred to as an addition voltage.

The basic setting value of V _P shown in step S55 is an appropriate +1 when printing on plain paper with humidity of 50 to 70%.
The default setting is 100, and when the user opens the panel shown in FIG. 26, the default setting is this setting unless otherwise specified. With this default value as a reference, when the humidity fluctuates, +1300 V (from the default value to +200 V) at 70% or more is +700 V (from the default value to -400 V). In the tenth embodiment, the transfer added voltage set value under each of these humidity environments is set outside the transfer failure area shown in FIG.

Thereafter, step S56 to step S59.
To set the paper type, transfer material thickness, and image pattern.
To go. The transfer material is thick and the transfer electric field does not reach the toner.
For label paper and envelopes that are considered
Plain paper V at the boundary_P + 100V newly V_P ’And set
To do. Recycled paper, which is more susceptible to humidity than plain paper,
Plain paper (+ 1300V) V at 50% or less_P +100
V, plain paper (+ 700V) V at 70% or more_P -100V
Set to. For OHP, the same V as plain paper _P Good
I like it. The thickness setting shown in step S57 is a paper type
This is performed only when paper feed or recycled paper is selected. Cardboard
In case of each environment V_P + 100V, for thin paper
Each environment V_P -100V.

As for the image pattern in step S58, as shown in the control panel of FIG. 26, a text pattern for mainly printing letters and numbers,
On the contrary, it was divided into graph-like patterns centered on graphs and figures. The reason why the image is divided into these two image patterns is that the former is more likely to generate scattered images in a low humidity environment, and when the applied voltage is increased until this is improved, the transfer charge penetrates the transfer material in the latter pattern, causing the toner and This is because the so-called “penetration”, in which the photosensitive drum is positively charged, and the so-called “through-through” development, in which the toner and the photosensitive drum are positively charged, occur. Therefore, only when printing a text pattern in an environment where the humidity is 50% or less, the added voltage is the V _P value +100 V set by the paper type or the like.

Further, in the case of performing double-sided printing in the double-sided printing determination in step S59, it is taken into consideration that the dryness of the paper is increased by passing through the fixing device during the printing of the first side and the resistance value is also increased. , And V _{P is} set to (V _P + 100V). FIG. 29 shows a summary of the above series of control results.

As described above, according to the tenth embodiment,
By determining the transfer conditions based on the printer environment information from the host, you can easily adapt to each environment, each paper type, and pattern.
In addition, the transfer bias can be set appropriately. Therefore, "transfer omission" in a high humidity environment and "scattering" at a low humidity can be prevented. Further, since it is not necessary to provide an expensive sensor for detecting the printing environment in the printer body, the cost can be reduced.

Further, since the printer is remotely operated from the place where the host is installed, it is not necessary to go to the setting position of the printer and set it. [Eleventh Embodiment] In the tenth embodiment described above, the transfer condition is controlled by controlling the transfer voltage. However, the present invention is not limited to the above example, and in a printer that performs constant current control during printing for transfer bias control, a value for constant current control according to printer environmental conditions is set. Good. An eleventh embodiment according to the present invention will be described below in which a constant current control value is set in accordance with printer environmental conditions in a printer in which a constant current control is performed for transfer bias control during printing.

The structure of the eleventh embodiment is similar to that of the tenth embodiment described above. In the case of the eleventh embodiment, what is considered to be influenced by the transfer condition from the environmental condition is the humidity, the paper size, the paper type, and the image print pattern. 11th
The setting control of the constant current value in the embodiment will be described below with reference to the flow chart in FIG.

In the control panel shown in FIG. 26, the information set by the user is transferred to the printer at the same time as the print signal IN in step S61. In step S62, the CPU first determines the transfer current corresponding to the humidity setting. Usually, since the indoor environment is 50% to 70%, for example if it is implemented on the control panel thereto, CPU Letter, set to a proper 2.0μA control A4 size (I _T set).

Next, in step S63, a current value correction process based on the image pattern is performed. In this case, only when the setting of Gurafuitsuku on the panel of FIG. 26 (I _T -0.
5) μA is set to prevent the graphic image from being jerky due to the excessive transfer current. For example, when an A4 plain paper is printed with a graphic pattern at a humidity of 50 to 70%, a constant current control of 1.5 μA is performed.

Then, in step S64, the set value set according to the paper type is corrected. In the eleventh embodiment, the recycled paper / label paper has the same setting as the plain paper, and is set to 2.0 μA only in the case of the setting of OHP. This is because OHP is not easily affected by humidity. And step S
At 65, the current value is corrected according to the paper size. Regarding the paper size, A4, Letter, and Legal have almost the same paper width, so the constant current value is not corrected. On the panel shown in FIG. 26, the set current value is changed only when envelopes or other small size sheets are set. In this case, since the transfer roller comes into contact with the photosensitive drum more, the current contributing to the transfer is smaller than that at the time of A4 size printing, and the constant current value is 0.5 μA for the purpose of compensating for that.
I was up.

Then, the transfer current value I _T is determined with reference to the correction values in steps S62 to S65 surrounded by a thick frame in step S66. Then perform printing during the constant current control by the step S67 in the transfer current value I _T determined in this step S66. The constant current value setting in the eleventh embodiment by the above control is as shown in FIG. 31 when shown in the same manner as FIG. 29 shown in the tenth embodiment.

As described above, according to the eleventh embodiment,
Since it becomes possible to easily apply an appropriate transfer bias according to the resistance value of the transfer roller and the resistance value of the transfer material, “transfer missing” and “scattering” are performed as in the tenth embodiment.
It is very effective for In addition, the cost is low and the convenience of remote control from the host is up. [Twelfth Embodiment] In the tenth and eleventh embodiments described above, the transfer condition is controlled by controlling the transfer voltage or the transfer current. However, the present invention is not limited to the above example, and in order to prevent transfer blurring that occurs when thick paper is printed, the pressure of the transfer roller and the pressure of the transfer roller are determined by the paper type and the paper thickness information from the host. The transfer condition may be controlled by changing the applied bias to obtain a good image output result. As described above, a twelfth embodiment according to the present invention in which the pressure applied to the transfer roller and the applied bias are changed according to the paper type and the paper thickness information will be described below.

FIG. 32 is a side view of the configuration of a printer to which the twelfth embodiment is applied. In FIG. 32, the cam 105 and the driving gear 1 are used as means for changing the pressure applied to the transfer roller.
06 and 107, which are driven by a motor (not shown). 104 is a cam 105 and a power supply spring 103
It is an insulator interposed between the two, and can move according to the movement of the cam 105. In the figure, 101 is a transfer roller core metal, and 102 is a core metal bearing.

In the twelfth embodiment, the printer having the configuration shown in FIG. 32 is set as follows in accordance with an instruction from the host, and the printing operation is performed. When the information on the thickness of the paper is received from the host and the paper is set to be thick, the pressing force of the transfer roller is increased to prevent the blur. In addition, when it is set to be normal or thin, the normal pressing force is applied.

In the twelfth embodiment, the normal pressure is set to a total pressure of 400 to 1000 g. The total pressure is set to 1000 to 2000 when the applied pressure is increased. Here, if the pressure applied to the transfer roller is increased, the image is likely to have a hollow area. Therefore, in the twelfth embodiment, the transfer bias is increased so that the hollow area does not easily occur (the peripheral speed of the transfer roller is set). The same effect can be obtained by stopping the drum peripheral speed rather than the drum peripheral speed).

The bias set value in the twelfth embodiment is 200 V up for the one set as in the tenth embodiment and 0.3 μA up for the one set in the eleventh embodiment. To do. As described above, according to the twelfth embodiment, it is possible to reliably prevent the blurring caused by the transfer roller deshocking at the registration roller and the pre-transfer guide, which has occurred at the time of printing on thick paper. Moreover, since the paper thickness information is transmitted from the host, it is not necessary to configure a sensor for detecting the paper thickness. Since the setting does not have to go to the printer installation position, it is very convenient for a networked printer or the like.

As described above, according to the tenth to twelfth embodiments, in the electrophotographic printer having the charging means for receiving the instruction and the image signal from the host device and outputting the image, By receiving at least one of the temperature condition, the humidity condition, the type / size of the transfer material, the pattern information of the output image, etc. when the printer is used, and changing the bias condition applied to the transfer means according to the received condition, the user However, an optimum image can be obtained by sending information such as external conditions and usage status from the host device to the printer according to the usage status.

Although the printer equipped with the contact transfer means has been described in detail, it goes without saying that the printer equipped with the corona transfer means has the same effect. [Thirteenth Embodiment] An optimum image can be formed even when the transfer condition of the transfer material, which is an output medium, is changed in response to an instruction from the host device 22. A thirteenth embodiment of the present invention in which the incident angle on the transfer roller 11 is adjusted by the thickness of the transfer material (recording paper) will be described below.

FIG. 33 is a diagram showing the construction of the electrophotographic printer in the thirteenth embodiment. The same components as those in FIG. 1 described above are designated by the same reference numerals and detailed description thereof will be omitted. 33 is different from the configuration of FIG. 1 in the first embodiment described above in that a transfer entrance guide 50 is arranged between the timing roller 10 and the transfer roller 11. Along with this, the point that a control mechanism for the transfer entrance guide 50 is provided is different from the first embodiment described above. Other basic configurations are the same as the configurations of FIGS. 2 to 5 of the first embodiment described above.

In the thirteenth embodiment, the host device 22
The transfer entrance guide 50 is controlled based on the information 23 from, and the position and angle with respect to the transfer roller 11 and the photosensitive drum 2 are controlled. When the toner image is transferred onto the transfer material by the transfer roller 11 (the same applies in the case of corona transfer), when the paper is thick and strong, the paper is splashed when it leaves the transfer entrance guide 50, and due to the shock, Image blur easily occurs.
On the other hand, when the paper thickness is thin and the stiffness is weak, it is difficult to regulate the entry point of the paper by the transfer entrance guide 50, and the paper enters the transfer roller 11 side before it hits the photosensitive drum 2 and is transferred before contacting the photosensitive drum 2. By receiving the electric field, the toner image is scattered around the characters. Therefore, in general, the thicker the paper thickness, the weaker the regulation of the paper entrance direction by the transfer entrance guide 50, and the thinner the paper thickness, the stronger the regulation of the paper entrance direction by the transfer entrance guide 50 is.

The same thing can be said for the image pattern, and it is desired that the text-based subject has less scattering and the graphic-based subject has less image blur. Further, the stiffness of the paper also changes depending on the temperature and humidity of the environment, and the resistance of the paper becomes higher as the temperature becomes lower and the humidity becomes lower, and the scattering becomes more noticeable. Since the optimum setting position of the transfer entrance guide 50 varies depending on the paper stiffness, resistance, and image pattern, it is very difficult to satisfy all of them with only one setting condition.

Therefore, in the thirteenth embodiment, by changing the setting position of the transfer entrance guide 50 based on the information 23 from the host 22, it is possible to obtain an optimum image for each of the above conditions. FIG. 34 is a diagram showing an example for changing the setting position of the transfer entrance guide 50. The transfer entrance guide 50 is driven and controlled by a control signal from the printer control unit 28 based on the information 23 from the host 22 and a gear train 52, 53, 5
It consists of 4,55,56. Then, the rotation of the drive unit 51 drives the gear trains 52, 53, 54, 55, 56,
As shown in the figure, the angle of the transfer entrance guide 50 attached to the gear 56 and integrally rotating around the shaft 57 is changed, and the incident point of the paper on the photosensitive drum 2 and the transfer roller 11 is controlled.

In the thirteenth embodiment, information from the host 22
23, the angle of the transfer entrance guide 50 is controlled in four steps.
Be done. That is, the leading edge position of the transfer entrance guide 50 is
The transfer line to the tangent line a between both the transfer roller 2 and the transfer roller 11.
The transfer entrance guide 50 from the contact portion between the roller 11 and the photosensitive drum 2.
The angle α formed by the straight line b connecting the tips of the^o , 0^o , 3
^o , 6^o Are fixed at four positions g1 to g4.

Here, the leading end position g4 of the transfer entrance guide 50
It is a setting position where the paper strongly hits the photosensitive drum 2, and there is little scattering of the image, but blurring is a conspicuous position. The position of g1 is the point where the paper enters the transfer roller 11 side, and is a position where image scattering easily occurs but blurring does not easily occur. FIG. 35 shows how the position control of the transfer entrance guide 50 is performed by the information 23 from the host 22. In the control of FIG. 35, the control is performed based on the paper thickness and the image information in the information 23.

[0134] paper thickness, a thin (basis weight 64 g / m ² or less), Normal (basis weight ^{64g / m 2 ~90g / m 2} ), is divided into three stages of a thick (basis weight 90 g / m ² or more) The image information is divided into two stages: text-based and graphic-based. The presence or absence of information from the host is identified, and when there is no information, the default state (paper thickness is normal in this embodiment,
In the image, the text main body is in the default state, and the position of the transfer entrance guide 50 is set to the angle g3).

Next, when the paper thickness information and the image information are input to the printer controller 28, the contents of Table 1 are stored in advance as a lookup table based on the information of the ROM 37 in the printer controller shown in FIG. Transcription entrance guide 5
The angle of 0 is controlled. For example, if the paper is thick and the image is mainly graphic, the image blurring is emphasized and the angle of the transfer entrance guide 50 is set to g1. If the paper is thin and the image is mainly composed of text, the angle of the transfer entrance guide 50 is set to g4 in consideration of the scattering of the image.

Although the above example describes an extremely extreme state, the angle of the transfer entrance guide 50 is set to the optimum position in the intermediate state of the above examples for other states. Further, in this embodiment, when either the paper thickness information or the image information does not exist, the missing information is processed in the default state. As described above, according to the thirteenth embodiment,
By changing the setting position of the transfer entrance guide 50 according to the thickness information of the paper and the image information from the host 22, it is possible to obtain the optimum transfer conveyance conditions according to the thickness of the paper and the image. In the thirteenth embodiment, the transfer entrance guide 50
Although the angle of was changed, it goes without saying that it is also possible to move it in parallel in the vertical and horizontal directions.

[Fourteenth Embodiment] In the above description, the optimum transfer condition is obtained by changing the incident angle of the paper as the transfer material before the transfer. However, the present invention is not limited to the above example, and it is also possible to obtain a good transfer condition by changing the conveyance angle of the transfer material after the transfer. As described above, the fourteenth embodiment of the present invention will be described in which the transfer angle of the transfer material is changed after the transfer to obtain a good transfer condition.

FIG. 36 is a diagram showing a post-transfer conveyance guide portion for explaining the fourteenth embodiment. The configuration of the printer and the relationship with the host 22 are the same as those in the above-described thirteenth embodiment, and a description thereof will be omitted. In the fourteenth embodiment, the height of the post-transfer conveyance guide is changed based on the information 23 from the host 22 to change the transfer material conveyance direction after the transfer. As a specific method, the motor 71 is driven by a signal from the printer control unit 28 based on the information 23 from the host 22, and the rib 74 of the post-transfer conveyance guide has three stages as shown in FIG. The height of the post-transfer conveyance guide rib 74 is controlled by rotating so as to substitute for the height (h1, h2, h3).

Specifically, the transfer roller 11 and the photosensitive drum 2 are connected to the common tangent line a between the transfer roller 11 and the photosensitive drum 2.
The transfer guide rib 74 after the transfer from the point where
The angle α formed by the straight line b connecting the vertices of 4 ^o (h1), 0 ^o
(H2) and -4 ^o (h3) are controlled.
This is for the following reasons. When the toner image is transferred onto the paper by the transfer roller 11, the transfer current is less likely to flow in a paper having a high resistance that is left in a low humidity, so that the image is easily disturbed after the transfer. On the other hand, by shifting the paper separation direction to the photosensitive drum 2 side, the transfer current easily flows and the above phenomenon can be prevented.

On the other hand, the paper left under high humidity has a weak electrostatic attraction force to the post-transfer conveyance guide 73, and when the separation direction of the paper is brought closer to the photosensitive drum 2 side, the trailing edge of the paper flaps as a cleaner. When it rubs against the bottom, it has a drawback. Also,
Even in the case of an image pattern, if the image is mainly composed of text, the image distortion tends to be a problem, and if the image is mainly composed of graphics, the trailing edge rubbing is likely to become a problem. Therefore, host 2
By changing the height of the post-transfer conveyance guide according to the information 23 from 2, the optimum transfer conveyance condition can be set according to the resistance of the paper and the image.

In the fourteenth embodiment, as the information from the host 22, three kinds of information of room temperature, humidity and image are input, and the temperature is low temperature, high temperature, normal three types, and humidity is low humidity and high humidity. , 3 types of ordinary information, and 2 types of information, mainly text and graphics mainly for images, are obtained.
FIG. 37 shows an example of controlling the height of the post-transfer conveyance guide rib 74 with respect to the above information in the fourteenth embodiment. As shown in FIG. 37, in the fourteenth embodiment, the post-transfer conveyance guide rib 74
It shows a state in which the height of is changed to three types of h1 to h3. For example, under low temperature and low humidity, the height of the post-transfer conveyance guide rib 74 is controlled to the lowest position h3 regardless of the image. Under other conditions, when the image is mainly text, it is controlled between h1 and h2, and when it is mainly graphic, it is controlled between h2 and h3.

As described above, according to the 14th embodiment,
Post-transfer conveyance guide 7 based on information 23 from host 22
By changing the height of 3, it is possible to set the optimum transfer and conveyance conditions according to the resistance of the paper and the image. [Fifteenth Embodiment] In the above description, the optimum transfer condition is obtained by changing the incident angle of the sheet which is the transfer material before the transfer or by changing the conveying angle of the transfer material after the transfer. However, the present invention is not limited to the above example, and it is also possible to obtain good transfer conditions by changing the paper transport speed. A fifteenth embodiment according to the present invention in which a good transfer condition is obtained by changing the paper conveyance speed in this way will be described.

FIG. 38 is a schematic view showing the transfer roller 11 driving portion for explaining the fifteenth embodiment. Since the configuration of the printer and the relationship with the host 22 are the same as those in the 13th embodiment described above, the description thereof will be omitted. In the fifteenth embodiment, the peripheral speed of the transfer roller 11 is changed based on the information 23 from the host 22 to change the paper conveyance speed.

As a concrete method, the information 2 from the host 22 is used.
3, the motor 81 is driven by a signal from the printer control unit 28 to drive the transfer roller 11 via the gear trains 82 and 83, and the rotational speed of the motor 81 is controlled (in the case of a pulse motor, the clock rate is changed). By doing so, the peripheral speed of the transfer roller 11 is changed. The peripheral speed of the transfer roller 11 is the highest peripheral speed v1 (2% of the peripheral speed of the photosensitive drum 2).
Fast), normal peripheral speed v2 (1 for 2 peripheral speeds of photosensitive drum)
%), And a low peripheral speed v3 (0.3% faster than the peripheral speed of the photosensitive drum 2).

This is for the following reason. In the transfer by the transfer roller 11, the character dropout phenomenon is generally apt to be a problem, and as a countermeasure against this, there is known a method in which the paper is quickly conveyed to the photosensitive drum 2. However, when the paper is conveyed to the photosensitive drum 2 quickly, the conveyance resistance of the paper is large when the paper thickness is large, so that the conveyance force by the transfer roller 11 becomes insufficient, and the paper required to prevent the hollow portion is not formed. Transport speed cannot be obtained. On the other hand, when the paper thickness is thin, the transfer roller 1
If the peripheral speed of 1 is too high, the image stretches and the image at the trailing edge of the paper runs off the paper.

Even if the image is mainly composed of text and mainly graphic, the paper conveying force of the transfer roller 11 is different, and in the case of mainly graphic, the paper slides against the photosensitive drum 2, so that the brake of the photosensitive drum 2 is applied. Since the force is weakened and the conveyance force of the transfer roller 11 becomes dominant, the image is easily stretched. In the case of mainly text, the opposite makes the image difficult to stretch.

As described above, since the image elongation differs depending on the paper thickness and the image pattern, the transfer roller 11
It is necessary to optimize the peripheral speed of. FIG. 39 shows a state in which the peripheral speed of the transfer roller 11 is controlled by the thickness of the paper and the image in the fifteenth embodiment. As shown in FIG. 39, in the fifteenth embodiment, for example, when the paper thickness is thick and the image is mainly composed of text, the peripheral speed of the transfer roller 11 is controlled to be the fastest v1. If the paper thickness is thin and the image is mainly graphic, the peripheral speed of the transfer roller 11 is controlled to v3, which is the slowest. In addition, in many cases, the peripheral speed of the transfer roller 11 is controlled between v2 and v3 in the case of the graphic main body and is controlled in the range of v1 and v2 in the case of the text main body.

As described above, according to the fifteenth embodiment,
The peripheral speed of the transfer roller 11 can be optimized against the fact that the expansion of the image differs depending on the thickness of the paper and the image pattern, and it is possible to effectively prevent the voids while maintaining the magnification of the image. [Sixteenth Embodiment] Next, a sixteenth embodiment according to the present invention will be described in which an excellent image is obtained by changing developing conditions in an electrophotographic forming process which is changed based on information from a host device. . Also in the 16th embodiment, the basic structure is substantially the same as the structure shown in FIGS. 1 to 5 of the first embodiment described above. However, in the sixteenth embodiment, since the developing conditions are controlled to control a good image, the configuration related to the developing device will be described in more detail. FIG. 39 is a sixteenth embodiment according to the present invention.
It is a block diagram of the electrophotographic printer of an Example. In FIG. 39, the developing device 4 in the configuration shown in FIG. 1 of the above-described first embodiment is shown in more detail.

In the sixteenth embodiment, the case where the developing device 4 adopts the jumping developing system using one-component magnetic negative toner will be described as an example. A one-component magnetic negative toner 4b is contained in the developing device 4. The toner 4b is conveyed as the aluminum developing sleeve 4a rotates in the direction of the arrow in the figure, and is supplied onto the electrostatic latent image formed on the photosensitive drum 2.

A magnet is installed in the developing sleeve 4a and has a role of holding the magnetic toner on the sleeve. A blade 4c made of urethane rubber is in contact with the developing sleeve 4a with a predetermined pressure to make the toner layer on the sleeve uniform and to give an electric charge to the toner. Developing sleeve 4a and photosensitive drum 2
Is installed with a gear tape of about 300 (μm), the photosensitive drum side equipment is grounded, and the AC + DC potential is superimposed on the developing sleeve side. The dark portion potential V _D of the photosensitive drum portion at this time is −7.
00 (V), the write portion potential _VL is about -100 (V), the AC component of the developing bias has V _pp of 1600 (V),
The frequency is 1800 (Hz).

FIG. 40 shows the host device 22 of the sixteenth embodiment.
9 is a flow chart showing control for obtaining an optimum image by changing the development contrast based on the humidity information input to the side.
In general, as the humidity increases, the charge imparting ability to the toner in the developing device decreases, which may reduce the image density. Therefore, in the sixteenth embodiment, when it is judged from the host side that the humidity is high, the development contrast is raised to prevent the density from being lowered. Hereinafter, description will be given along the flow chart of FIG.

First, in step S71, it is determined whether there is information from the host 22. If there is no information from the host 22, the process proceeds to step S72 to set the development contrast control to the default value. On the other hand, host 22
If there is information from, the process proceeds to step S73 to check the information. And low humidity and normal condition (humidity value 7
If it is less than 0%), the process proceeds to step S74 and step S75, respectively, and the correction is not performed, and the development contrast is set according to the initial setting. If the humidity is high in step S73, the flow advances to step S76 to change the setting so that the development contrast is increased by 50V.

FIG. 41 shows a control example of the developing contrast in the sixteenth embodiment including the correction processing by the above control. In FIG. 41, V _D is the dark portion potential on the photosensitive drum 2, and V _{d C} is the developing bias value applied to the developing sleeve. In the sixteenth embodiment, the dark portion potential V on the photosensitive drum 2 is used as means for changing the development contrast.
Changing d _C.

As described above, according to the sixteenth embodiment,
A good image can be obtained by changing the development contrast in the electrophotographic forming process which is changed based on the information from the host device. [Seventeenth Embodiment] In the above description, a good image was obtained by changing the development contrast. However, the present invention is not limited to the above example, and an optimum image can be obtained by changing the peripheral speed of the developing sleeve as the developing condition. A seventeenth embodiment according to the present invention in which an optimum image is obtained by changing the developing sleeve peripheral speed as the developing condition in this manner will be described below.

FIG. 42 is a diagram best representing the characteristics of the seventeenth embodiment according to the present invention, and FIG. 43 is a flow chart showing the control of the developing sleeve peripheral speed in the seventeenth embodiment. 42, the same components as those in FIG. 39 of the 16th embodiment described above are designated by the same reference numerals, and detailed description thereof will be omitted. First
In the seventh embodiment, in order to change the peripheral speed of the developing sleeve 4a with respect to the photosensitive drum 2, a driving means (not shown) dedicated to the developing sleeve 4a is provided, which is connected to the motor control section via the communication means 18a. Connection control is performed.

Next, the control for changing the peripheral speed in the seventeenth embodiment will be described with reference to the flow chart of FIG. First, in step S81, the presence / absence of humidity information from the host is checked. If there is no information from the host, step S8
Proceed to 2 and control by default value is performed. If there is information from the host, the flow advances to step S83 to check the humidity. When the humidity is low (less than 30%) or normal (30 to 70%), the process proceeds to step S84 or step S85, respectively, and the sleeve peripheral speed relative to the drum peripheral speed remains at 100% without correction. To do. On the other hand, when the humidity becomes high (70% or more), the process proceeds to step S86 to increase the sleeve peripheral speed to 150%. As a result, it is possible to prevent the concentration from decreasing in a high humidity environment. This is because when the humidity becomes high, the electric charge of the toner becomes small, the developing performance deteriorates, and the density decreases, so by increasing the sleeve peripheral speed, the toner supply amount to the latent image on the drum is increased. This is to prevent the concentration from decreasing.

As described above, according to the seventeenth embodiment,
By changing the peripheral speed of the developing sleeve as the developing condition,
The optimum image can be obtained. [Eighteenth Embodiment] As a change of developing conditions, an eighteenth embodiment according to the present invention in which the pressing force of the developing blade is changed based on the humidity information inputted from the host will be described below.

FIG. 44 is a view best showing the features of the eighteenth embodiment according to the present invention. In the figure, the same components as those in the sixteenth embodiment shown in FIG. 39 described above are designated by the same reference numerals, and detailed description thereof will be omitted. In the eighteenth embodiment, means 4d for changing the pressing force of the developing blade 4c against the developing sleeve 4d.
Means 4d for changing the pressure applied to the developing sleeve.
Is driven by a motor, for example, and this motor is controlled by the motor controller 18 via the communication means 18b.

FIG. 45 is a diagram showing in detail the blade pressure varying means of the eighteenth embodiment shown in FIG. In the figure, the developing blade 4c is a rubber blade made of urethane rubber, and the developing blade 4c is fixed to the blade mounting plate 4f by adhesion or the like. Blade mounting plate 4
The gear train is arranged at f, and the blade mounting plate 4f
By rotating a motor (not shown) through a gear shaft 4d provided with a small diameter gear screwed to the gear train and a large diameter gear screwed to the gear 4e fixed to the motor drive shaft, It is configured to move up and down. That is, by controlling the rotation of the motor, the gear 4e fixed to the drive shaft also rotates as shown by the arrow in FIG. Then, the gear shaft 4d also rotates as shown by the arrow in the figure. This rotation is due to the blade mounting plate 4
It is also transmitted to the gear train of f and moves up and down corresponding to the rotation of the motor of the blade mounting plate 4f.

FIG. 46 is a flow chart showing the control for changing the pressing force of the developing blade based on the humidity information input from the host in the 18th embodiment. In the figure, first, in step S91, the presence or absence of humidity information from the host side is confirmed. If there is no information from the host side, step S
Proceeding to 92, the pressing of the developing blade is controlled by the default value. On the other hand, if there is humidity information from the host side, the flow proceeds to step S93 to check the humidity information.

Generally, when the humidity is high, the electric charge of the toner is low and the developing performance is deteriorated. On the contrary, when the humidity is low, the toner causes a charge gap, which also causes the deterioration of the developing performance. Therefore, when the humidity is low, it is necessary to lower the blade pressure to lower the charge imparting ability to the toner and prevent the charge gap, and when the humidity is high, it is necessary to increase the blade pressure to enhance the toner imparting ability. . For this reason,
In this embodiment, when the information of low humidity (less than 30%) is given, the process proceeds to step S94, where the blade pressure is reduced to 2
The pressing of the developing blade is controlled to 0 (gf / cm).

On the other hand, when the information on the normal environment (30 to 70%) is given, the process proceeds to step S95, and the pressing of the developing blade is controlled by the normal setting pressure of 30 (gf / cm) without correction. Also, in step S93, high humidity (70% or more)
If the information is given, the flow advances to soot 976 to increase the blade pressure to 40 (gf / cm) to control the pressing of the developing blade.

As described above, according to the eighteenth embodiment,
By changing the pressure applied to the developing sleeve based on the information from the host device as the developing condition, a good image can be obtained without being affected by the surrounding environment. [Nineteenth Embodiment] As a change in developing conditions, the developing contrast is reduced based on the paper type information from the host, the amount of toner adhered to the image portion is suppressed, and electrostatic offset is prevented. The nineteenth embodiment will be described below. Specifically, in the case of thick paper (100 g / m ² or more) and OHP, it is characterized in that the development contrast is lowered, the amount of toner deposited on the image portion is suppressed, and electrostatic offset is prevented. Electrostatic offset means that when an unfixed image passes through the fixing device nip, the electrical holding force on the toner of the paper weakens, or when the toner is attracted to the fixing roller side by the electrostatic force, This is development in which the toner image is transferred to the fixing roller side.

In this development, the larger the amount of toner in the image area, the thicker the paper and the larger the heat capacity,
It tends to occur easily. This correlates with the fixability, and when the amount of toner is large, heat is not transferred uniformly over the entire area of the toner on the image, and incompletely melted freener toner is attached to the fixing roller side. Further, if the paper is thick, the heat capacity becomes large, so that the heat taken by the paper is increased, the heat is not sufficiently transferred to the toner, and the offset is likely to occur.

FIG. 47 shows a nineteenth embodiment according to the present invention.
The development contrast is reduced based on the paper type information from the host.
To reduce the amount of toner adhesion to the image area and reduce electrostatic
Represents a flow chart showing control to prevent
It In FIG. 47, first, in step S101, is it the host?
Check for the presence of such information. If there is no information from the host
To proceed to step S102, use the default
Take control of the trust. On the other hand, there is information from the host
If so, go to step S103, what is the paper type?
To find out. The type of paper is cardboard (100 g / m ² that's all),
Alternatively, in the case of OHP, the process proceeds to step S104 and the current
Develop by lowering image contrast (for example, lowering 100V)
Contrast is controlled and toner amount on the image area
Try to reduce.

On the other hand, if the paper type is other than these, the process proceeds from step S103 to step S105, and control is performed with normal development contrast without correction. First
FIG. 48 shows an example of the developing bias V _DC in the ninth embodiment. In the nineteenth embodiment, in the case of thick paper or OHP, Vd _C is shifted by 100 V in order to reduce the development contrast. This degree of shift has a sufficient effect for preventing offset.

As described above, according to the nineteenth embodiment,
By controlling the development contrast based on the paper type information from the host, a good image can be obtained without being affected by the recording paper type. [Twentieth Embodiment] A twentieth embodiment of the present invention for obtaining a good image by controlling the developing frequency based on the image information from the host will be described below.

In the twentieth embodiment, when the image information is centered on the text, the fog is apt to stand out, and therefore the operation for increasing the developing frequency is performed. On the other hand, when it is centered on the graphic, no correction is made and the initial setting is left. It is characterized by doing. FIG. 49 shows a flow chart showing the processing for controlling the developing frequency based on the image information from the host in the twentieth embodiment. In FIG. 49, first, step S1
At 11, the presence or absence of information from the host side is checked. If there is no information from the host side, the flow advances to step S112 to control the developing frequency with the default value. On the other hand, if there is information from the host side, the flow advances to step S113 to check the image form information. If the image form information is the center of the graphic, the process proceeds to step S114, and the development frequency is controlled without correction.

On the other hand, if the image form information is centered on the text in step S113, the process proceeds to step S115 to increase the developing frequency. This is because the text has more white areas, and fog is more visible. FIG. 50 is a diagram showing the relationship between the developing frequency and the fog density in the twentieth embodiment. The fog density referred to here is obtained by the following equation.

[0170]

[Equation 8] * For measurement, Tokyo Denshoku Co., Ltd. DENSITOMETER TC-6DS
use.

From FIG. 50, it can be seen that fog decreases as the developing frequency is increased. However, if the frequency is increased too much, the developing performance is lowered and the image density is lowered. Therefore, the density of the solid black portion is 1.3 as a practically no problem level.
In order to ensure (measured with a Macbeth densitometer), it is desirable that the upper limit of the developing frequency is about 2000 Hz. Considering the above, in the twentieth embodiment, the developing frequency is set to the initial setting frequency (180
0 Hz) and the center of the text, the development frequency is increased to 2000 Hz. As a result, even in an image centered on a text with many white backgrounds, fog can be reduced without degrading the image quality. [Twenty-first embodiment] Next, in the electrophotographic process, by changing the setting condition of the cleaning means for the photosensitive drum 2 which is an image carrier, the user can change the setting condition from the host device 21 according to the use condition. A twenty-first embodiment according to the present invention will be described in which information such as external conditions and usage conditions can be sent to the printer 20 of this embodiment to obtain an optimum image.
In the twenty-first embodiment, the same structures as those of the first embodiment described above are not shown in the drawings, and the same reference numerals are given in the drawings to omit the detailed description of the same structures.

FIG. 51 is a view showing the arrangement of an electrophotographic printer according to the 21st embodiment of the present invention. 51 is different from the configuration of the first embodiment shown in FIG. 1 described above in that the configuration of the cleaner control unit 201 for controlling the cleaner 5 is clearly shown. Then, in the twenty-first embodiment, the setting operation of the cleaner 5 is performed by the cleaner control unit 2
Controlled by 01.

In the twenty-first embodiment, the connection between the host and the printer may be configured as shown in FIG. 2 of the first embodiment, and the control panel of the printer 20 displayed on the host 21 is also shown in FIG. The same as the first embodiment shown in FIG. FIG. 52 shows the printer 20 according to the twenty-first embodiment.
The block configuration of the operation control unit is shown. In FIG. 52,
The difference from the above-described first embodiment shown in FIG. 4 is that a cleaner control unit 201 is added. The operation of the cleaner control unit 201 is under the control of the printer control unit 27.

Here, the user instructs the printer 20 via the host 21 about the configuration of the cleaner 5 provided in the printer 20 in the twenty-first embodiment having the above-described configuration and the operating environment conditions of the printer 20, A method of correcting the setting conditions for the cleaner 5 will be described. Fig. 53
As shown in FIG. 3, a cleaning blade 24 made of urethane rubber is provided at the opening of the cleaner 5 on the side of the photosensitive drum 2.
1 is provided, and this one edge is the photosensitive drum 2
When the residual toner remaining on the surface of the photosensitive drum 2 that does not contribute to the transfer reaches the contact portion at the transfer portion (not shown), the cleaning blade 241 contacts the surface.
The residual toner that has been scraped off by means of the toner is collected in the collecting chamber 242.

A scooping sheet 243 prevents the residual toner scraped off the surface of the photosensitive drum 2 by the cleaning blade 241 from falling outside the collecting chamber 242. The cleaning blade 241 is swingable about an axis o, and an eccentric cam 44 that is rotated and positioned about an axis o'by a drive motor (not shown) is used to form the photosensitive drum 2 at a predetermined angle.
It is configured to abut the surface.

In the twenty-first embodiment, as shown in FIG. 54, as standard settings, the setting angle = θ25 ^° and the penetration amount δ =
It has a diameter of 0.8 mm and is in contact with the surface of the photosensitive drum 2.
The set angle is the ridgeline PQ of the tip of the cleaning blade.
The angle between the vertical ST of PQ and the tangent line UV of the surface of the photosensitive drum at the virtual intersection R between the surface of the photosensitive drum and the surface of the photosensitive drum, and the amount of penetration means the length of QR. The contact pressure of the cleaning blade 241 against the surface of the photosensitive drum 2 at this time is 30 g / cm.

An elastic material such as urethane rubber used for the cleaning blade 241 generally has a small impact resilience and a large loss coefficient in a low temperature environment. For this reason, it becomes impossible to follow the minute irregularities on the surface of the photosensitive drum 2, and so-called cleaning failure easily occurs. That is, FIG.
Even if the standard setting shown in 4 is an appropriate value for maintaining a sufficient cleaning ability in a normal temperature environment, it is not preferable in a low temperature environment, and the contact pressure is further increased, and the residual force is more forcibly retained. It is necessary to peel off the toner.

However, when the contact pressure is set high in this way, the repulsion elasticity of the cleaning blade 241 becomes large and the loss coefficient becomes small at high temperature, so that so-called chattering occurs and an unpleasant noise or noise is generated. Cleaning failure due to vibration is likely to occur. That is, the contact pressure with respect to the surface of the photosensitive drum 2 for maintaining a sufficient cleaning capability is different between low temperature and high temperature. Therefore, in the twenty-first embodiment, the user sets the environment conditions for using the printer 20 to the host 2
1 to the printer 20 and bring the cleaning blade 241 into contact with the surface of the photosensitive drum 2 with an appropriate contact pressure under the environmental conditions, thereby providing a sufficient cleaning ability even under any use environment. It is possible to maintain.

The contact pressure value control operation of the cleaning blade 241 with respect to the surface of the photosensitive drum 2 in the twenty-first embodiment will be described below with reference to the flow chart of FIG.
In FIG. 55, the user instructs the printer 20 via the host 21 on the usage environment condition of the printer 20, and the set angle θ of the cleaning blade 241 is changed,
Cleaning blade 241 for the surface of the photosensitive drum 2
It is a flow chart for controlling the contact pressure of No. 1 to a value suitable for the environment.

First, in step S121, it is determined whether or not there is information from the host 21. When there is no information from the host 21, the process proceeds to step S122, where the set angle θ of the cleaning blade 241 with respect to the surface of the photosensitive drum 2 is θ.
Is controlled to a default value, 25 ^° in the twenty-first embodiment. On the other hand, if there is information from the host 21, the process proceeds to step S123 to check if the temperature in the information is low temperature, normal temperature or high temperature. When the temperature in the information is low, the process proceeds to step S124, in order to prevent the cleaning failure due to the reduction of the repulsion elasticity of the cleaning blade 241 and the increase of the loss coefficient, the cleaning blade for the surface of the photosensitive drum 2 is prevented. The set angle θ of 241 is corrected to 28 ^° , and the contact pressure of the cleaning blade 241 with respect to the surface of the photosensitive drum 2 is increased.

On the other hand, if the temperature in the information is room temperature in step S123, the process proceeds to step S122 without any correction.
The set angle θ of the cleaning blade 241 is controlled to a default value, 25 ^° in the twenty-first embodiment. On the other hand, if the temperature in the information is high, step S1
25, the set angle θ of the cleaning blade 241 with respect to the surface of the photosensitive drum 2 is set to 22 in order to prevent the cleaning failure due to the increased repulsion elasticity of the cleaning blade 241 and the reduced loss coefficient.
The contact pressure of the cleaning blade 241 with respect to the surface of the photosensitive drum 2 is lowered by setting the value to ^o .

As described above, according to the twenty-first embodiment,
From the host device to the printer when using the temperature and humidity conditions,
By receiving at least one of the above conditions and changing the setting condition of the cleaning means in accordance with the received condition, the user can print information such as external conditions and usage status from the host device according to the usage status. You can get the optimum image.

[Twenty-second Embodiment] In the twenty-first embodiment described above, this is realized by changing the set angle θ as means for changing the contact pressure of the cleaning blade 241 with respect to the surface of the photosensitive drum 2. However, it goes without saying that this may be realized by changing the penetration amount δ.

By changing the penetration amount δ, the user can send information such as external conditions and usage status from the host device to the printer according to the usage status to obtain an optimum image according to the present invention. The twenty-second embodiment will be described below. Also in the twenty-second embodiment, as the standard setting shown in FIG. 54, the photosensitive drum 2 is in contact with the surface of the photosensitive drum 2 with the set angle = θ25 ^o and the penetration amount δ = 0.8 mm. The contact pressure of the cleaning blade 241 is 30 g / cm.

In the twenty-second embodiment, the specific constitution is the same as that of the twenty-first embodiment. The point is that the penetration angle δ of the cleaning blade 241 is changed instead of changing the set angle θ of the cleaning blade 241. Are different. The operation of controlling the contact pressure value of the cleaning blade 241 with respect to the surface of the photosensitive drum 2 by changing the penetration amount δ of the cleaning blade 241 of the twenty-second embodiment will be described below with reference to FIG. 56.

In FIG. 56, the user instructs the printer 20 via the host 21 on the environmental conditions under which the printer 20 is to be used, and by changing the amount δ of penetration of the cleaning blade 241, the cleaning blade 241 with respect to the surface of the photosensitive drum 2 is changed. It is a flow chart for controlling the contact pressure of No. 1 to a value suitable for the environment. First, step S131
Then, it is determined whether or not there is information from the host 21.
When there is no information from the host 21, the process proceeds to step S132, and the invasion amount δ of the cleaning blade 241 with respect to the surface of the photosensitive drum 2 is controlled to a default value, which is “1.8 mm” in the 22nd embodiment.

On the other hand, if there is information from the host 21, the flow advances to step S133 to check if the temperature in the information is low temperature, normal temperature or high temperature. If the temperature in the information is low, the process proceeds to step S134, in order to prevent cleaning failure due to the impact resilience of the cleaning blade 241 becoming smaller and the loss coefficient becoming larger, the photosensitive drum 2 is prevented.
The penetration amount δ of the cleaning blade 241 with respect to the surface is set and corrected to “1.0 mm”, and the contact pressure of the cleaning blade 241 with respect to the surface of the photosensitive drum 2 is increased.

On the other hand, if the temperature in the information is room temperature in step S133, the process proceeds to step S132 without any correction.
The invasion amount δ of the cleaning blade 241 is controlled to be a default value, which is “0.8 mm” in the twenty-second embodiment. On the other hand, if the temperature in the information is high, the process proceeds to step S135, in which the cleaning blade 241 has a large repulsion elasticity and a loss coefficient is small. The penetration amount δ of the cleaning blade 241 is set and corrected to “0.6 mm” to lower the contact pressure of the cleaning blade 241 with respect to the surface of the photosensitive drum 2.

As described above, according to the 22nd embodiment,
From the host device to the printer when using the temperature and humidity conditions,
By receiving at least one of the above, and changing the invasion amount δ of the cleaning means accordingly, the user can obtain information such as external conditions and usage status from the host device according to the usage status. You can send it to the printer and get the optimum image.

[Twenty-third Embodiment] In the above description,
A cleaning blade is provided as a cleaning means,
An example has been described in which the user instructs the printer 20 via the host 21 on the operating environment conditions of the printer 20 by controlling the contact pressure of the cleaning plate to change the setting conditions for the cleaner 5. However, the cleaning means of the present invention is not limited to the above example, and even when a cleaning roller is provided as the cleaning means, at least one of the temperature condition, the humidity condition and the like when the printer is used is similarly received from the host device. By changing the setting conditions of the cleaning means accordingly, the user can send information such as external conditions and usage status from the host device to the printer according to the usage status to obtain the optimum image. Can be done. The twenty-third embodiment according to the present invention configured as described above will be described below.

In the twenty-third embodiment, in the printer 20 equipped with the cleaner 5 having the cleaning roller 45 as the cleaning means, the user instructs the printer 20 via the host 21 on the environmental conditions of use of the printer 20, and the above-mentioned cleaner is used. A method of correcting the setting condition for 5 will be described. As shown in FIG. 57, the cleaning roller 24 is provided in the opening portion of the cleaner 5 on the photosensitive drum 2 side.
5 is provided, and is in contact with and rotated on the surface of the photosensitive drum 2 with a predetermined nip width. The cleaning roller 245 has an elastic body layer 245 made of an elastic material such as silicon sponge, urethane rubber, chloroprene rubber, or epichlorohydrin rubber on the outer periphery of the metal cored bar 245a.
b is formed, and then the outer peripheral surface of the photosensitive drum 2 is covered with a tube-shaped film 245c made of an insulating material such as nylon. It is rotating in the forward direction at a peripheral speed 1.2 times the peripheral speed. A resin blade 246, which is made of polyethylene or the like and serves as a charging member and a scraper, is in contact with the surface of the cleaning roller 245, which frictionally charges the surface of the cleaning roller 245 to a polarity opposite to the polarity of the residual toner. At the same time, it has a function of scraping off the residual toner adhering to the surface of the cleaning roller 245. When the residual toner remaining on the surface of the photosensitive drum 2 without contributing to the transfer arrives at the abutting portion at a transfer portion (not shown), it is electrostatically adsorbed and removed by the cleaning roller 245, and then the resin blade 246 The residual toner is stored in the collection chamber 242.

Now, the cleaner 5 having the above structure
In the printer 20 including the above-mentioned printer, and using the corona charging unit that has been frequently used in the past, instead of the contact charging unit, so-called image deletion easily occurs in a high humidity environment. There is.
That is, even if the standard setting is an appropriate value for maintaining sufficient cleaning ability in a normal humidity environment, it is not preferable in a high humidity environment, and if the peripheral speed of the cleaning roller 245 is set to be high. This time, in a low-humidity environment, drum scratches and cleaning defects associated therewith are likely to occur. It is considered that this is because the elastic material forming the cleaning roller 245 is hardened and the surface of the photosensitive drum 2 is easily roughened.

In other words, the peripheral speed of the cleaning roller 245 for maintaining a sufficient cleaning ability is different between high humidity and low humidity. Therefore, according to the present invention, the user instructs the printer 20 via the host 21 on the environmental conditions under which the printer 20 is to be used, and the cleaning roller 245 is moved to the surface of the photosensitive drum 2 at an appropriate peripheral speed under the environmental conditions. By contacting and rotating with, it is possible to maintain a sufficient cleaning ability even under any usage environment.

FIG. 58 shows a flow chart for controlling the peripheral speed of the cleaning roller 245 to a value suitable for the environment by the user instructing the printer 20 via the host 21 on the environmental conditions of use of the printer 20. Show. First, in step S141, it is determined whether there is information from the host 21. If there is no information from the host 21, the process proceeds to step S142, and the peripheral speed of the cleaning roller 245 is controlled to a default value, which is 1.2 times the peripheral speed of the photosensitive drum 2 in this embodiment.

On the other hand, if there is information from the host 21, the process proceeds to step S143 to check the humidity information from the host 21 to see if it is high humidity, normal humidity or low humidity. When the humidity is high, the process proceeds to step S144, and the peripheral speed of the cleaning roller 245 is set and corrected to be 1.5 times the peripheral speed of the photosensitive drum 2 in order to prevent image deletion. If the humidity is normal in step S143, the process proceeds to step S142, and the peripheral speed of the cleaning roller 245 is controlled by the default value without any correction.

On the other hand, if the humidity is low, the process proceeds to step S145, in which the peripheral speed of the cleaning roller 245 is set to the photosensitive drum 2 in order to prevent the scratches on the drum and the defective cleaning.
The peripheral speed is adjusted to be 1.0 times the peripheral speed, that is, the speed is adjusted to be constant. As described above, according to the twenty-third embodiment, the cleaning roller 2 receives the humidity condition when the printer 20 is used from the host device 22 and responds to the humidity condition.
By controlling the peripheral speed of 45, the user can send information such as external conditions and usage status from the host device to the printer according to the usage status to obtain an optimum image.

[Twenty-fourth Embodiment] In the twenty-fourth embodiment, in the printer 20 provided with the cleaner 5 having the brush roller 247 as the cleaning means, the user uses the host 21 to determine the operating environment condition of the printer 20. And a method of correcting the setting conditions for the cleaner 5 will be described. Also in the twenty-fourth embodiment, the configuration other than the cleaning means is the same as that of the above-described embodiment, and therefore detailed description of the other configurations will be omitted.

As shown in FIG. 59, a brush roller 247 is arranged at the opening of the cleaner 5 on the side of the photosensitive drum 2, and the contact / rotation control is performed on the surface of the photosensitive drum 2 with a predetermined nip width. To be done. When the residual toner remaining on the surface of the photosensitive drum 2 without contributing to the transfer arrives at the nip portion at a transfer portion (not shown), it is electrostatically adsorbed and removed by the brush roller 247.

The residual toner thus attracted is collected by the collecting roller 248 and then scraped off by the blade 2.
It is scraped off from the surface of the collecting roller 248 by 49 and is stored in the collecting chamber 242. In the brush roller 247, a conductive brush 247b is planted on the surface of a conductive cylindrical body 247a made of aluminum or the like, and a DC voltage of 300 V having a polarity opposite to the charging polarity of the residual toner is applied as a standard setting. Due to this DC voltage, the residual toner on the surface of the photosensitive drum 2 is electrostatically adsorbed.

The collecting roller 248 is a conductive cylindrical body made of aluminum or the like, and a DC voltage of 600 V having a polarity opposite to the charging polarity of the residual toner is applied as a standard setting. With respect to the residual toner adsorbed on the conductive brush 247b by this DC voltage, the conductive brush 247 is removed.
The residual toner is collected from the conductive brush 247b by applying an electrostatic attractive force stronger than that of b. Further, the scraping blade 249 is an elastic body such as urethane rubber,
This edge portion is in contact with the surface of the collecting roller 248, and scrapes off the residual toner from the surface of the collecting roller 248.

The fiber material used for the brush roller 247 generally has a low resistance in a high humidity environment, so that the conductive brush 247b moves to the photosensitive drum 2.
Electric discharge occurs on the surface. Therefore, the photosensitive layer is deteriorated or the surface of the photosensitive drum 2 is non-uniformly charged, and the residual toner once collected by the conductive brush 247b adheres to the non-uniform portion again, thus resulting in poor cleaning. Is likely to occur.

That is, even if the standard setting is an appropriate value for maintaining a sufficient cleaning ability in a normal humidity environment, it is not preferable in a high humidity environment, and it is necessary to further lower the applied voltage. . However, if the applied voltage is set low in this way, then in a low humidity environment,
The resistance of the conductive brush 247b increases, and the cleaning failure easily occurs due to the weakening of the electrostatic attraction of the residual toner on the surface of the photosensitive drum 2. That is, the bias applied to the brush roller 247 for maintaining a sufficient cleaning capability is different between high humidity and low humidity.

Therefore, in the twenty-fourth embodiment, the user instructs the printer 20 via the host 21 on the environmental conditions under which the printer 20 is to be used, and while applying an appropriate bias to the brush roller 247 under the environmental conditions, By bringing this into contact with the surface of the photosensitive drum 2, it becomes possible to maintain a sufficient cleaning ability even under any usage environment.

FIG. 60 shows the printer 2 in the twenty-fourth embodiment.
The flow chart for controlling the bias applied to the brush roller 247 to a value suitable for the environment by the user instructing the printer 20 via the host 21 about the humidity information of the environment where 0 is used is shown. First, in step S151, it is determined whether or not there is information (humidity information) from the host 21. When there is no information from the host 21, the process proceeds to step S152, and the bias applied to the brush roller 247 is controlled to the default value, 300v in this embodiment.

On the other hand, if there is information from the host 21, the flow advances to step S153 to check if the humidity is high humidity, normal humidity or low humidity. If the humidity is high, the process proceeds to step S154, and the bias applied to the brush roller 247 is controlled to be set to 100 v and corrected. If the humidity information is normal humidity in step S153, the flow advances to step S152 to control the bias applied to the brush roller 247 to the default value 300v. On the other hand, if the humidity information is low, step S
Proceeding to 155, the bias applied to the brush roller 247 is controlled so as to be set and corrected to 500 v.

As described above, according to the twenty-fourth embodiment,
By receiving the humidity condition when the printer 20 is used from the host device 22 and controlling the bias voltage value of the brush roller 247 in accordance with the humidity condition, the user can adjust the external condition from the host device according to the usage condition. It is possible to send information such as usage and usage status to the printer to obtain an optimum image. The present invention may be applied to a system including a plurality of devices or an apparatus including one device. Further, it goes without saying that the present invention can also be applied to the case where it is achieved by supplying a program to a system or an apparatus.

[0207]

As described above, at least one of the temperature condition of the installation place, the humidity condition, the thickness of the output paper, the type of paper, the pattern information of the image to be formed, etc. is received from the external device, and in response thereto, By changing the electrophotographic image forming process, the user can send information such as external conditions and the use state to the image forming apparatus according to the use state, and an optimum image can be obtained.

Further, various detecting devices are not required in the image forming apparatus, the cost is reduced, and the detecting device need not be built in, so that the device can be downsized. Further, even if it is technically difficult to detect such as the thickness of the paper, it can be easily made by human judgment and the accuracy can be improved.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an electrophotographic printer according to an exemplary embodiment of the present invention.

FIG. 2 is a connection diagram of a host device and a printer device in this embodiment.

FIG. 3 is a diagram showing a controller panel of a printer device displayed on a host device in the present embodiment.

FIG. 4 is a detailed block diagram of an operation control unit of the printer in this embodiment.

FIG. 5 is a detailed block diagram of the printer control unit shown in FIG.

FIG. 6 is a flow chart showing laser emission intensity correction control in this embodiment.

FIG. 7 is a diagram showing a control panel displayed on a host device in a second embodiment according to the present invention.

FIG. 8 is a diagram showing a control panel displayed on a host device in a third embodiment according to the present invention.

FIG. 9 is a flow chart when the host side takes in a state set in the printer in the third embodiment.

FIG. 10 is a diagram showing a controller panel of a printer device displayed on a host device in a fourth embodiment of the present invention.

FIG. 11 is a diagram showing a relationship between temperature and potential of an electrophotographic photosensitive member.

FIG. 12 is a diagram showing a relationship between humidity and electric potential of an electrophotographic photosensitive member.

FIG. 13 is a diagram showing a relationship between an exposure amount E and a bright portion potential V _L.

FIG. 14 is a flow chart showing correction processing of laser emission intensity in a fourth example.

FIG. 15 is a control panel of the printer device displayed on the host device in the fifth embodiment of the present invention.

FIG. 16 is a diagram showing a lighting control of a semiconductor laser according to a fifth embodiment.

FIG. 17 is a diagram showing the relationship between the lighting ratio of image signals and the image density in the fifth embodiment.

FIG. 18 is a diagram showing an example of a control circuit for delaying an image signal in the fifth embodiment.

FIG. 19 is a diagram showing a printer according to a sixth embodiment of the present invention.

FIG. 20 is a diagram showing humidity dependence of an appropriate voltage of an AC component of a bias applied to a charging roller.

FIG. 21 is a diagram showing the temperature dependence of the appropriate voltage of the AC component of the bias applied to the charging roller.

FIG. 22 is a diagram showing a relationship between a line pitch and a spatial frequency.

FIG. 23 is a flow chart for controlling the frequency of the AC component of the bias applied to the charging roller in the eighth embodiment according to the present invention.

FIG. 24 is a diagram showing the relationship between fog, differential voltage, and humidity.

FIG. 25 is a flow chart for controlling the voltage of the DC component of the bias applied to the charging roller in the ninth embodiment of the present invention.

FIG. 26 is a view showing a control panel of the printer displayed on the host in the tenth embodiment according to the present invention.

FIG. 27 is a flow chart showing a transfer voltage setting process in the tenth embodiment.

FIG. 28 is a transfer addition voltage setting graph with respect to humidity in the tenth embodiment.

FIG. 29 is a diagram showing a setting state of a transfer addition voltage in the tenth embodiment.

FIG. 30 is a flow chart showing a transfer current setting process in an eleventh embodiment of the present invention.

FIG. 31 is a diagram showing a setting state of a transfer current value in the eleventh embodiment.

FIG. 32 is a schematic side view of a printer transfer portion according to a twelfth embodiment of the present invention.

FIG. 33 is a view showing the arrangement of an electrophotographic printer according to the 13th embodiment of the present invention.

FIG. 34 is a diagram showing a transfer / transport unit which is a main part of the thirteenth embodiment.

FIG. 35 is a diagram showing conditions for controlling the position of the transfer entrance guide in the thirteenth embodiment.

FIG. 36 is a view showing a transfer / transport unit which is a main part of a fourteenth embodiment according to the present invention.

FIG. 37 is a diagram showing conditions for controlling the height of post-transfer conveyance guide ribs in the fourteenth embodiment.

FIG. 38 is a diagram showing a transfer / transport unit which is a main part of a fifteenth embodiment according to the present invention.

FIG. 39 is a view showing the arrangement of an electrophotographic printer according to the 16th embodiment of the present invention.

FIG. 40 is a flow chart showing the control of the 16th embodiment.

FIG. 41 is a diagram showing an example of developing bias setting in the sixteenth embodiment.

FIG. 42 is a view showing the arrangement of an electrophotographic printer according to the 17th embodiment of the present invention.

FIG. 43 is a flow chart showing the control of the 17th embodiment.

FIG. 44 is a view showing the arrangement of an electrophotographic printer according to the 18th embodiment of the present invention.

FIG. 45 is a diagram showing a detailed structure of a main part of the eighteenth embodiment.

FIG. 46 is a flow chart showing the control of the eighteenth embodiment.

FIG. 47 is a flow chart showing control of a nineteenth embodiment according to the present invention.

FIG. 48 is a diagram showing an example of developing bias setting in a nineteenth embodiment.

FIG. 49 is a flow chart showing control of the twentieth embodiment according to the present invention.

FIG. 50 is a diagram showing the relationship between developing frequency and fog.

FIG. 51 is a view showing the arrangement of an electrophotographic printer according to the 21st embodiment of the present invention.

FIG. 52 is a block diagram showing the detailed structure of the operation control unit of the printer in the twenty-first embodiment.

FIG. 53 is a diagram showing a detailed configuration of a cleaning device forming a main part of the twenty-first embodiment.

54 is a view for explaining the standard setting and action of the cleaning blade shown in FIG. 53. FIG.

FIG. 55 is a flow chart showing contact pressure control of the cleaning blade in the twenty-first embodiment.

FIG. 56 is a flow chart showing the contact pressure control of the cleaning blade in the twenty-second embodiment of the present invention.

FIG. 57 is a diagram showing a detailed configuration of a cleaning device in a twenty third embodiment of the present invention.

FIG. 58 is a flow chart showing peripheral speed control of the cleaning roller in the twenty-third embodiment.

FIG. 59 is a diagram showing a detailed configuration of a cleaning device in a twenty-fourth embodiment according to the present invention.

FIG. 60 is a flow chart showing bias control applied to the cleaning brush in the twenty-fourth embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Electrophotographic cartridge 2 Electrophotographic photoreceptor 3 Charging roller 4 Developing device 4a Developing sleeve 4b One-component magnetic negative toner 4c Blade 4d Means for changing pressure on developing sleeve 4e Motor drive shaft 4f Blade mounting plate 5 Cleaner 6 Laser scanner 9 Paper feeding Roller 10 Timing roller 11 Transfer roller 16 Exposure control unit 17 High voltage control unit 18 Motor control unit 18a, 18b Communication means 19 Fixing control unit 20 Paper feed control unit 21 Printer device 22 Host device 23 Communication cable 26 Interface 27 Image development unit 28 Printer control unit 29 Semiconductor laser 30 Main motor 31 Scanner motor 33 Paper feed clutch 34 Sensors 35 CPU 36, 37 ROM 38 RAM 39 I / O port 40 AND gate 41 Delay IC 41 Delay IC 41 delaying IC 42 switches 43 LED array 50 transfer entrance guide 51 driver 52,53,54,55,56,72,82,83
Gears 71, 81 Motor 73 Post-transfer conveyance guide 74 Post-transfer conveyance guide rib 101 Transfer roller core metal 102 Core metal bearing 103 Power supply spring 104 Insulator 105 Cam 106, 107 Driving gear 201 Cleaner controller 241 Cleaning blade 242 Recovery chamber 243 Rake sheet 244 Eccentric cam 245 Cleaning roller 246 Resin blade 247 Brush roller 248 Collection roller 249 Scraping blade

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Internal reference number FI Technical display location G03G 15/16 21/00 111 (72) Inventor Tatsukazu Tsukita 3-30 Shimomaruko, Ota-ku, Tokyo No. 2 within Canon Inc. (72) Inventor Tatsunori Ishiyama 3-30-2 Shimomaruko, Ota-ku, Tokyo Within Canon Inc. (72) Yuko Tanaka 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Satoru Izawa 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (30)

[Claims] 1. An electrophotographic image forming apparatus that prints an image by receiving an instruction and an image signal from an external device connected thereto, wherein at least the environmental conditions of the installation location and the conditions of the recording medium are supplied from the external device. An image forming apparatus characterized by changing the electrophotographic image forming process in accordance with the above conditions. 2. The image forming apparatus according to claim 1, wherein the condition and the image information received from the external device are retained in the device until the information is updated or the power of the device is turned off. Forming equipment. 3. The image forming apparatus according to claim 1, wherein the apparatus is started up according to default information or a condition received from an external apparatus when the power is turned off. 4. The image forming apparatus according to claim 3, wherein the startup information can be set from an external device. 5. The image forming apparatus according to claim 1, wherein information can be sent to an external device in reverse, if necessary. 6. The electrophotographic image forming process to be changed is the emission intensity of the image exposure light source.
The image forming apparatus described. 7. The image forming apparatus according to claim 6, wherein the light emission intensity of the image exposure light source is changed by changing the light emission duty ratio. 8. An electrophotographic image forming apparatus comprising a charging means for printing an image upon receiving an instruction and an image signal from an external device connected thereto, wherein the external device has environmental conditions and an output image when the device is used. The image forming apparatus is characterized in that it receives at least one of the pattern information, and changes the bias condition applied to the charging unit according to the condition. 9. The image forming apparatus according to claim 8, when the external device receives an environmental condition when the device is used, the voltage of the AC component of the bias applied to the charging unit is changed according to the environmental condition. An image forming apparatus characterized by the above. 10. The image forming apparatus according to claim 8, wherein when the pattern information of the output image is received from the external device,
An image forming apparatus, wherein a frequency of an AC component of a bias applied to the charging unit is changed according to the pattern information. 11. The image forming apparatus according to claim 8, when the external device receives an environmental condition when the device is used, the voltage of the DC component of the bias applied to the charging unit is changed according to the environmental condition. An image forming apparatus characterized by the above. 12. An electrophotographic image forming apparatus having a transfer means for printing an image in response to an instruction and an image signal from a connected external device, wherein the external device has environmental conditions when the device is used and a transfer material. When receiving at least one of the information and the pattern information of the output image, the image forming apparatus changes the transfer condition of the transfer unit according to the condition. 13. The image forming apparatus according to claim 12, wherein the transfer unit is a system that controls a constant voltage during printing,
The image forming apparatus is characterized in that the transfer condition is changed by changing the constant voltage value. 14. The image forming apparatus according to claim 12, wherein the change of the transfer condition is performed by changing the pressure of the transfer roller to the image carrier and the transfer bias. 15. An electrophotographic image forming apparatus for printing an image in response to an instruction and an image signal from a connected external device, the environmental condition, the output medium condition and the output image of the device being used from the external device. An image forming apparatus, which receives at least one of pattern information and changes a conveyance condition of the output medium according to the condition. 16. The image forming apparatus according to claim 15, wherein the change of the transport condition changes the transport speed of the output medium. 17. The change of the transport condition is to change the incident direction of the output medium with respect to the transfer means for transferring the toner image to the output medium.
5. The image forming apparatus according to item 5. 18. The image forming apparatus according to claim 15, wherein the change of the transport condition changes the transport direction of the output medium after the transfer of the toner image by the transfer unit is completed. 19. An electrophotographic image forming apparatus for printing an image in response to an instruction and an image signal from an external device connected thereto, the environmental condition, the output medium condition, and the output image when the device is used from the external device. An image forming apparatus that receives at least one of the pattern information and changes the developing condition according to the condition. 20. The image forming apparatus according to claim 19, wherein the change of the developing condition changes the developing bias. 21. The development bias is changed by the development bias D.
21. The image forming apparatus according to claim 20, wherein the C component is changed. 22. The image forming apparatus according to claim 19, wherein the change of the developing condition changes the peripheral speed of the developing sleeve. 23. The change of the developing condition is to change the contact pressure of the elastic blade.
The image forming apparatus described. 24. The image forming apparatus according to claim 19, wherein the change of the developing condition changes the frequency of the developing AC bias. 25. An electrophotographic image forming apparatus, comprising: a cleaning unit for cleaning an image carrier, which outputs an image in response to an instruction and an image signal from an external device connected thereto. An image forming apparatus, characterized in that, when at least one of environmental conditions is received, the setting condition of the cleaning unit is changed according to the condition. 26. The image forming apparatus according to claim 25, wherein the change of the setting condition of the cleaning unit is a change of the contact pressure of the cleaning unit with respect to the image carrier. 27. The cleaning unit is a blade made of an elastic body, and the contact pressure of the blade with respect to the image carrier is changed by changing the set angle of the blade with respect to the image carrier. Item 26. The image forming apparatus according to Item 26. 28. The cleaning means is a blade made of an elastic body, and the contact pressure of the blade with respect to the image carrier is changed by changing the amount of penetration of the blade with respect to the image carrier. Item 26. The image forming apparatus according to Item 26. 29. An electrophotographic image forming apparatus comprising cleaning means for cleaning an image carrier, which outputs an image in response to an instruction and an image signal from an external device connected thereto, wherein the cleaning means is at least rotatable. An image forming apparatus comprising: a roller, and changing the peripheral speed of the roller according to the condition when at least one environmental condition during use is received from the external device. 30. An electrophotographic image forming apparatus comprising a cleaning unit for cleaning an image carrier, which outputs an image in response to an instruction and an image signal from an external device connected thereto, and a bias applying unit for the cleaning unit. When the bias applying unit receives at least one environmental condition during use from the external device, the bias applying unit changes the bias applied to the cleaning unit according to the condition.