JPH04157475A - Image formation device - Google Patents

Abstract

PURPOSE:To facilitate the exchange of expendable articles, the maintenance and exchange of materials and the processing of jam, by making a frame movable to the 1st position where the frame is furnished to a device main body and image formation is conducted, and the 2nd position where replenishment and exchange to developer replenishment portions can be conducted. CONSTITUTION:When an opening/closing door 200 is opened manually as a display lamp L is lighted, a motor M1 starts normal rotation, and a frame 100 is moved to a device front side through a pinion P and a rack R. The normal rotation of the motor M1 is kept up by means of a photo sensor 103A, and in addition, stopped. Accordingly, the frame 100 is protruded to a position shown by a chain line, by opening the door 200 manually, and stops, and is set at the 2nd position where toner replenishment to respective developer replenishment portions is possible. After the completion of toner replenishment to respective developer replenishment portions, the reverse rotation of the motor M1 is started by pushing a reset button R.B, and the frame 100 is moved toward a device main body inside. As a result, the frame 100 is again restored to the 1st position where image formation is possible. As a result, the work of maintenance is facilitated, and also developer replenishment can be executed easily and rapidly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electrophotographic image forming apparatus that forms an image on a transfer material such as a copying machine or a printer.

[Background of the invention]

There are many ways to obtain color images using electrophotography.
A device has been proposed. For example, JP-A-61-10077
As disclosed in Publication No. 0, a latent image is formed and developed in accordance with the number of separated colors of an original image on a photoreceptor drum serving as an image forming member, and is transferred onto a transfer drum each time the development is performed. There is a method in which a multicolor image is formed on a paper and then transferred onto a transfer material to obtain a color copy. In addition to the photoreceptor drum, the device using this method requires a transfer drum large enough to transfer one image onto the shoulder surface of the photoreceptor, and the device does not have a large and complicated structure. Inevitable.

Furthermore, as disclosed in, for example, Japanese Patent Application Laid-Open No. 61-149972, a latent image is formed and developed on a photoreceptor drum according to the number of separated colors of the original image, and is transferred onto a transfer material each time it is developed. There is a way to obtain a multicolor copy. With this method, it is difficult to overlay multicolored images with high precision,
It is not possible to obtain a good quality color copy.

Another method is to repeatedly form a latent image on a photoconductor drum according to the number of separated colors of the original image and develop it with color toner, and then overlap the color toner images on the photoconductor drum and transfer the images to obtain a color image. . The basic process of forming a multicolor image is disclosed in Japanese Patent Application Laid-open No. 60-75850 and No. 60-75850 by the present applicant.
-76766, 60-95456, 60-95
No. 458, No. 60-158475, and the like.

In a multicolor image forming apparatus that obtains a color image through such superimposition, a plurality of developing devices containing different color toners are arranged around the periphery of the photoreceptor drum. The photosensitive drum is rotated multiple times to develop the latent image on the photosensitive drum to obtain a color image.

On the other hand, in image forming apparatuses such as monochrome analog copying machines using an electrophotographic method and copying machines and printers using semiconductor laser/LED scanning systems, various photoreceptors, developer carriers, cleaning members, and developing devices with long service lives are used. A part of the image forming means is made into a cartridge in order to replenish and replace the toner when it is exhausted, and the member that integrates the main parts of the image forming means is taken out of the apparatus for maintenance or replacement. The configured one will be suggested. Furthermore, various configurations have been proposed in which the conveyance path of the transfer material on which an image is formed by the image forming means is opened to make it easier to take out the transfer material when clearing a jam.

A typical configuration of these is as disclosed in Japanese Patent Publication No. 58-54392, in which the photoreceptor drum, developer, cleaner, etc. are integrally attached to a support member and can be pulled out from the main body of the apparatus, and each unit Proposals have been made to facilitate the replacement and repair of the gutter, and the next one was published in Japanese Patent Application Laid-Open No. 1983-1982, which integrated the main parts of these image forming means and made them disposable.
Japanese Patent Laid-Open No. 154255 discloses a printer configuration that uses a similar disposable cartridge and forms a latent image on a photoreceptor drum by dot exposure and scanning writing using a semiconductor laser. There is.

Further, these publications disclose a structure in which the upper housing of the split structure is opened to open the transfer material conveyance path and take out the transfer material in the event of a jam. A structure is adopted in which a disposable process cartridge is replaceably disposed in an upper housing having a two-part structure, and attempts are made to improve the workability of cartridge replacement and ease of jam removal. In addition, with emphasis on ease of replacement of process cartridges, mainly replenishment toner cartridges and cleaning cartridges for recovered toner, the structure is divided into two parts. Japanese Patent Laid-Open Publication No. 1161/1983 discloses a device which aims to improve this.

In addition, the above-mentioned structure is made into a vertical type, and
No. 44058, No. 63-244059, No. 63-24
No. 4064, Japanese Unexamined Patent Publication No. 1-179168, etc., are proposed in order to improve same-direction operation and jam handling.

[Problem that the invention seeks to solve]

However, if the developing device, image carrier, etc. are made into a process cartridge and are replaceable with respect to the apparatus main body, the process cartridge can be easily loaded into and removed from the apparatus main body.
In addition, there is no need to worry about toner or developer leaking or collapsing from the developing device when it is inserted into or removed from the main body of the device, and it also has a process cartridge that does not cause these problems when dealing with transfer material jams. No compact printer has been proposed.

In addition, Japanese Patent Laid-Open No. 58-190961 proposes that in a printer with a two-part structure, the process cartridge installed in the upper part is kept horizontal at all times to prevent waste toner from collapsing when the upper housing is opened. It is disclosed in the official gazette. Although efforts have been made to make loading and jam removal easier, the structure does not solve problems such as toner drop-off and leakage during cartridge loading, jam removal, and other maintenance replacement operations.

In particular, Japanese Patent Laid-Open No. 58-2003 has a structure in which a disposable cartridge is provided in the upper casing with a two-part structure that facilitates jam handling.
72159, and Japanese Patent Laid-Open No. 72159 proposes that a process cartridge is installed in the lower housing to facilitate replenishment and replacement of collected toner, and the process cartridge for developing, cleaning, photosensitive drums, etc. is lifted upward when handling jams. All of the proposals in Japanese Patent No. 58-1161 are at odds with the workability of process cartridge replacement and the ease of jam removal. Furthermore, in these process cartridges, the developing section
The cleaning part is on the bottom and faces the transfer pole across the paper feed and conveyance path, so even if the cartridge is tightly sealed, the developer This causes toner to spill from the cleaner section, causing stains inside the machine and staining the transfer paper.

The link disclosed in Japanese Utility Model Application Publication No. 63-195357 incorporates a process cartridge inside and forms a flat feeding and conveying path at the top. There are restrictions on the conveyance path from the to the fixing section, and the problem with the conveyance section remains unresolved. Furthermore, it is not easy to clear jams when divided into two parts, it is not compact as a whole due to the stacked paper feeding configuration of the upstand, and the opening angle of the upper housing is restricted when divided into two parts, making it difficult for users to operate. However, it has not yet been possible to provide a device with excellent performance.

As a result of solving and improving this point, the present invention facilitates the replacement of consumables, maintenance and replacement of materials, and jam handling.
A further object of the present invention is to provide an image forming apparatus configured such that all of the above operations can be performed from the same side of the apparatus.

[Means to solve the problem]

The above object is to provide an image forming apparatus in which an image forming process means is mounted on a frame that can be inserted into the main body of the apparatus, wherein the image forming process means includes at least an image forming member and a charging, developing and cleaning unit that can be attached to and removed from the frame. units and a developer replenishment section, and the pedestal has a first position where it is attached to the main body of the apparatus and performs image formation, and a position where the mount is connected to the developer replenishment section in response to a signal from the developer consumption detection means. Supply/
This is achieved by an image forming apparatus characterized in that it is movable to the vg2 position where exchange can be performed.

[Embodiment] FIG. 1 is a sectional view showing a configuration of an embodiment of an image forming apparatus of the present invention.

In the figure, a photosensitive drum 10 is a drum-shaped image forming member, and the drum is coated with an OPC photosensitive material, and is grounded and rotated clockwise.

20 is a scorotron charger that applies an electric charge to the photoreceptor on the circumferential surface of the photoreceptor drum 10; 13 is an image exposure light or a laser beam that is focused on the circumferential surface of the photoreceptor drum 10 by an exposure optical system (not shown); This is the image exposure section where the image is projected.

For example, a laser writing system unit is used as the exposure optical system. When a color signal output from an image reading device separate from the image forming device is input to the laser writing system unit 7, this laser writing system unit converts a laser beam ( wavelength 78
0 nm) is rotated and scanned by a polygon mirror, passes through an fθ lens, has its optical path bent by a reflection mirror, and is uniformly charged in advance by the charger 20;
Projected onto the 0 circumferential surface.

On the other hand, when scanning is started, the laser beam is detected by the index sensor, modulation of the laser beam by the first color signal is started, and the modulated laser beam scans the circumferential surface of the photoreceptor drum 10. Therefore, a latent image of the first color is formed in the image area on the photoreceptor drum 10 by the main scanning by the laser beam and the sub-scanning by the rotation of the photoreceptor drum 10. This latent image is reversely developed by a developing means containing toner of, for example, yellow (Y) as a first color, and a yellow toner image is formed on the circumferential surface of the photoreceptor drum 10. The obtained toner image in the image area is transferred to the photoreceptor drum 1 while being held on the surface of the photoreceptor drum 10.
It passes under the transfer means and cleaning means which are separated from the zero point, and enters the next copy cycle.

That is, the photoreceptor drum 10 is charged again by the band charger 20, and then the second photoreceptor drum 10 is charged with electricity outputted from the signal processing section.
The color signal ' is input to the writing system unit, and the color signal 't;
Writing is performed on the peripheral surface using a color signal of 1g2 to form a latent image. This latent image is created using a second color such as magenta (
Reversal development is performed by the developing means containing the toner M), and a magenta toner image is formed. This magenta toner image is formed over the previously formed yellow toner image.

The toner image of the image area obtained in this way is held on the circumferential surface of the photoreceptor drum 10 and passes under the transfer means and the cleaning means which are separated from the circumferential surface of the photoreceptor drum 10, and is used for the next copy cycle. to go into.

Similarly, writing is performed on the photosensitive drum 10 using the third color signal to form a latent image. This latent image is reversely developed by a developing means containing toner of a third color, for example, cyan (C).

A color image is obtained by forming this cyan toner image on top of the yellow and magenta toner images described above. Furthermore, a developing means containing black toner may be provided, and a high-quality color image may be obtained by further superimposing black toner images in the same manner as described above.

41 to 43 are yellow for the above development, respectively;
The developing device is a developing means that accommodates magenta and cyan toner, and both have similar structures.

Charging by the charger 20 provided on the photosensitive drum 10 and its periphery, exposure by the laser writing system unit for each color, and development by the developing devices 41 to 43 are performed three times for each color, and the photosensitive drum 10 is A color toner image is formed on the image area on the circumferential surface of the body drum 10 by overlapping.

Reference numerals 51 and 52 refer to a path for recording paper, which is a transfer material according to size, which is fed one by one from a transfer material supply device, and 53 a transfer section 160 in synchronization with the movement of the color toner image on the photoreceptor drum 10. This is a registration roller for conveying the recording paper to.

70 is a transfer belt device, 71 is a transfer belt which is a belt portion, 72 and 73 are rollers made of conductive metal material,
The upstream roller 72 is a roller that has a rotatable shaft that is at a predetermined potential that is grounded or close to the grounded state, and the downstream roller 73 is a roller that drives the transfer belt 71 and has a fixed shaft. Reference numeral 74 denotes a belt support member, one end of which has the axis of the roller 73 as a fixed shaft, and the other end connected to the movable shaft of the roller 72, and is connected to the roller 72 by an elastic member (not shown).
is biased so that it is positioned downward. Therefore, the transfer belt 71 is normally retracted from the surface of the photoreceptor drum 10, and during transfer, the eccentric cam 77, which is operated under the control of the device control section, is attached to the belt support member 74 via the leaf spring 78.
is pressed upward in the figure, rotates counterclockwise around the roller 73, and the rollers 76 provided at both ends of the belt support member 74 move the side edges of the circumferential surface of the photoreceptor drum 10 outside the image area. The transfer belt 71 is in contact with the photoreceptor drum 10
The transfer unit 160 is brought into contact with the transfer unit 160 of

Reference numeral 79 denotes a cleaning blade of a belt cleaning device that scrapes off the toner adhering to the transfer belt 71, and 95 denotes a toner collection box (not shown) in which the toner scraped off by the cleaning blade 79 is collected by a toner transport pipe having a flexible transport screw inside. Transport to.

Reference numeral 16 denotes a transfer device which is a charger for transfer provided at a position facing the transfer unit 160, and reference numeral 60 denotes an opening thereof at a position opposite to the roller 72 in the wedge-shaped cross-sectional space between the transfer belt 71 and the photosensitive drum 10. This is a paper charger disposed such that its portion faces the transfer belt 71.

After the development by the developer 43 containing the third color toner on the photoreceptor drum IO is started as described above, the registration roller 53 is operated, the transfer belt device 70 is pressed, and the discharge wire of the paper charger 60 is activated. High voltage is applied almost simultaneously to both.

As a result, the paper charger 60 performs corona discharge toward the recording paper fed one by one from the transfer material supply device, and charges the recording paper to the same polarity as the toner on the photoreceptor drum 10.

The paper charger 60 efficiently and reliably charges the roller 72, which is close to the ground, as a counter electrode, and also charges the transfer portion 1
Since it is provided very close to the transfer belt 60, there is little loss of charge during conveyance, and the recording paper can be firmly attracted and held on the transfer bell 71 and conveyed to the transfer section 160.

When the front end of the recording paper reaches the transfer fE160, the recording paper is pressed against the photosensitive drum 10 by the transfer belt 71. Then, the transfer device 16 charges the toner on the photosensitive drum IO with a polarity opposite to that of the toner, and transfers the toner image onto the recording paper. The recording paper onto which the toner image has been transferred is transferred to a conveyor belt 21
The sheet is further conveyed to the fixing section 22, where it is fixed by heat welding, and then discharged onto an external sheet discharge tray 23. Reference numeral 55 denotes a separation claw for preventing the recording paper from accidentally entering upwards.

The photosensitive drum 10, which has been transferred by the rotation and pressure of the transfer belt 71 and the charging action of the transfer device 16, is cleaned by a cleaning device 90. The photosensitive drum 1 includes a toner collecting roller 92 for collecting residual toner.
The cleaning blade 91 is in a retracted state while a toner image is being formed on the zero circumferential surface, and is brought into pressure contact with the photoreceptor drum 10 to perform cleaning after the transfer is completed. Further, a static eliminating lamp 93 is located upstream of the cleaning device 90, and a static eliminating lamp 94 is located downstream. The lamp 94 uniformly eliminates static electricity from the cleaned circumferential surface of the photosensitive drum 10 so that uniform charging is performed. Further, a toner conveying pipe 95A having a toner conveying screw made of a flexible material is provided at the bottom of the cleaning device 90, and conveys waste toner collected by cleaning to a toner collecting box (not shown). The photosensitive drum IO that has been cleaned begins the next image forming process.

The aforementioned photosensitive drum 10. The image forming process means such as the charger 20, the developing devices, and the cleaning device 90 are assembled into the pedestal 100, and are inserted horizontally from the front side of the device as one body into the main body.

The pedestal 100 is a highly rigid frame whose ridges are made of angle materials, and each of the image forming process means is supported by bearings or sandwiched between substrates fixed to the front and rear sides of the pedestal 100. .

When attaching or detaching the pedestal 100, a pair of left and right opening/closing doors 200 (indicated by two-dot chain lines) provided on the front surface of the apparatus main body are opened symmetrically, and the convex rail members 101A provided on both sides of the pedestal 100 are opened. It is inserted and removed by sliding into and engagement with a concave guide member 101B provided on the device main body side, or by releasing the engagement.

Further, the pedestal 100 has developer replenishing parts 41A, 42A, and 43A protruding from the front surface thereof, which are connected to the respective developing devices, and as shown in FIG. By moving to the position shown with , toner can be replenished to each developer replenishing section.

The movement of the pedestal 100 is automatically started by the operation of a control section that receives a signal from a detection means that detects the consumption of developer in each developing device.

That is, each of the developer replenishing sections described above is equipped with a sensor S as a means for detecting the remaining amount of toner contained therein, and when the remaining amount of toner in each section decreases to a predetermined amount or less, a toner replenishment signal is output.

I; A motor M1 capable of forward and reverse rotation is installed inside the main body of the apparatus, and its pinion P is meshed with a rack R formed on the pedestal lOO.

Furthermore, when the pedestal 100 slides along the guide member 101B, the light shielding plate 1 on the upper surface is
02 turns the photosensor 103A fixed on the main body side and Iha 103B from ON to OFF, or from OFF to O.
Switch to N.

When the amount of each developer is equal to or more than the specified amount, the mount 100 is moved to the light shielding plate 1 as shown by the solid line in FIG.
The 02/7 sensor 103A is in the OFF and OFF position, and each of the image forming process means accommodated is set in the first position where image formation is possible.

When any one of the above-mentioned sensors S detects a value below the specified amount of toner, the signal is sent to the control section, and the display lamp L of the corresponding color provided in the operation section 80 on the front of the device as a display means lights up. At the same time, the normal rotation drive of the motor M1 is put on standby.

First, a first example will be explained. When the operator manually opens the opening/closing door 200 due to the lighting of the indicator lamp L, the rotation thereof turns on a start switch (not shown), and the motor M1 starts to rotate normally, and the motor M1 starts to rotate through the pinion P and the rack R. Move the pedestal 100 to the front side of the device.

For normal rotation of the motor Ml, the mount 100, that is, the light shielding plate 102
This is sustained by the switching of the 7 photosensor 103A from OFF to ON due to the movement of the photosensor 103A.
It is stopped by switching B from ON to OFF.

Therefore, by manually opening the opening/closing door 200, the pedestal 100 is projected to the position shown by the dotted line in FIG. is set to the second position.

After toner has been replenished to each developer replenishment section, by pressing a reset button R-B provided on the operation section, the motor M1 starts to reverse rotation, and the pedestal 100 is moved into the main body of the apparatus.

The reverse rotation of the motor Ml is continued by switching the photosensor 103B from OFF to ON, and is further stopped by switching the photosensor 103A from ON to OFF.

As a result, the pedestal 100 is returned to the first position where the image formation is possible again.

Next, when the opening/closing door 200 is closed and the above-mentioned starting switch is turned off, the developer replenishment sequence of the control section is canceled and the above-mentioned indicator lamp L is turned off. The indicator lamp L can also be configured to be turned off by replenishing toner or replacing the replenishing unit itself. FIG. 3 is a flowchart showing the above operation.

In the first embodiment described above, the opening/closing door 200 is opened and closed manually. However, a motor is further installed on the rotation bearing part, and the display lamp L It is also possible to automatically open and close the opening/closing door 200 at the same time as the lighting and extinguishing of the light.

FIG. 4 is a plan view showing the second embodiment. FIG. ) is an opening/closing door 20O
A and B show a state in which the doors are automatically opened and the pedestal 100 has moved to the second position.

The opening/closing doors 20OA and 200B have rotating shafts 201A and 201B.
A door that opens and closes using a hinge, each with a fixed arm 202A.
, 202B are provided. Fixed arm 202A, 20
At the tip of the link lever 2B, the pins 204A and 204B are connected to one end of the link levers 21OA and 210B, and the link lever 2
The other ends of 1OA and 210B are connected to each other by a pivot 211.

On the other hand, M2 is a motor capable of forward and reverse rotation with a built-in reduction gear, and one end of a lever 220 is fixed to the shaft of the motor M2, and the other end of the lever 220 has a long hole 221, and the pivot 211 is loosely fitted.

With the structure described above, when the motor M2 rotates clockwise, the doors 200A and 200B open simultaneously, and when the motor M2 rotates counterclockwise, the doors 200A and 200B open simultaneously.
, 200B close their doors at the same time. Photo sensor 222A
A sensor 222B detects the closed position of the doors 20OA and 200B, and a sensor 222B detects the open position of the doors 200A and 200B.

The operation of the second embodiment will be explained with reference to the flowchart shown in FIG. First, when the remaining amount of toner in the developer replenishment section decreases to a specified amount or less, the sensor S detects this,
As a result, the control unit turns on the indicator lamp L, simultaneously rotates the motor M2 clockwise, and stops the motor M2 when the photosensor 222B detects that the door is completely opened. Subsequently, the motor Ml starts normal rotation, the pedestal 100 moves, the photosensor 103B is detected, and it stops at the second position.

The operator presses the reset button R-B after replenishing toner or replacing the toner replenishing section.

When the reset button R-B is pressed, the motor M1 is reversely rotated to return the gantry lOO from the second position to the first position, and is stopped by detection by the photosensor 103A. Subsequently, the control unit rotates the motor M2 counterclockwise, and the 7-point sensor 222
A detects and stops. This stopping position is the opening/closing door 20OA
, 200B is the closed state position.

〔Effect of the invention〕

The present invention not only makes it extremely easy to maintain process materials in the image forming section, but also makes it possible to easily and quickly replenish developer to each developing means without missing an opportunity. As a result, it has become possible to provide an image forming apparatus that can be inspected and maintained well and that can always produce high-quality images with appropriate image density or color balance.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional configuration diagram of an image forming apparatus of the present invention, FIG. 2 is a side view of the main parts thereof, and FIGS. 4(a) and (b) are front views of the main parts.
3 and 5 show the process of replenishing developer.
Flowchart of the second embodiment.

Claims (3)

[Claims] (1) In an image forming apparatus in which an image forming process means is mounted on a frame that can be inserted into the apparatus main body, the image forming process means includes at least an image forming member and a charging, developing, and cleaning device that can be attached to and removed from the frame. Each unit and a developer replenishment section are provided, and the pedestal is attached to the apparatus main body at a first position where image formation is performed, and the developer replenishment section is refilled based on a signal from a detector that detects developer consumption. - An image forming apparatus characterized in that it is movable to a second position where it can be replaced. (2) The movement of the pedestal from the first position to the second position is indicated by a signal from the detection means on a display means provided on the apparatus main body, and is performed when the opening/closing door of the apparatus main body is manually opened. 2. The image forming apparatus according to claim 1, wherein: (3) Image forming according to claim (1), characterized in that an opening/closing door of the apparatus body is automatically opened in response to a signal from the detection means, and the pedestal is moved from the first position to the second position. Device.