JPS63241573A - Image forming device - Google Patents

Abstract

PURPOSE:To shorten time for recording at the time of recording the same monochromatic image continuously by selecting taps in such a manner that a circulation operation is carried out in a memory array of the small capacity corresponding to the size of an original in the auxiliary scanning direction thereof when said size is smaller than the size corresponding to the total memory capacity in the direction where a shift register with taps is shifted. CONSTITUTION:Selection of a recording mode is executed by an external operation of a switching means S3 for switching the circuit connection of the shift register 7 with taps and a tap switching means S4 for selecting the taps of the register 7. Selection of the taps is executed to meet the size of the original image in the auxiliary scanning direction (rotating direction of the image carrier). The tap which decreases the shift quantity is, therefore, selected and the repetitive period at the time of circulating the recording data is shortened when the size of the original image in the auxiliary scanning direction is small. The time for continuous recording of the same monochromatic image in multiple sheets is thereby shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an improvement in an image forming means of an image forming apparatus that forms a visible image on an image carrier based on an image signal by electrophotography.

(Prior Art) FIG. 3 shows an example of the arrangement of an image carrier and various components surrounding the image carrier of a conventionally known multicolor image forming apparatus having two image exposure sections. It is a figure showing an outline.

FIG. 2 is a diagram showing a typical example of a multicolor image forming process of a conventional multicolor image forming apparatus. The basic process of multicolor image formation is disclosed in Japanese Patent Application Laid-Open No. 60-75850.60-7676.
6.6 (1-95456, 60-95458, 60-1
58475 etc. are publicly known. FIG. 2 will be explained.

FIG. 2 is a diagram showing how the potential on the surface of the image carrier changes when the surface of the image carrier is uniformly charged by a charger and then subjected to image exposure by the image exposure section. The charger and the image exposure section constitute a latent image forming means. In FIG. 2, PH is the exposed area on the image carrier, DA is the unexposed area on the image carrier, T1 is the toner attached to the image carrier during the first development, and DUP is the exposed area PH. For the purpose of explanation, the polarity of the latent image is assumed to be positive.

During the process, the image carrier is uniformly charged by a charger and has a positive potential E.

In process (2), a first image exposure is applied by a laser or the like, and the potential of the exposed portion PH decreases in accordance with the amount of light.

In process ■, the electrostatic latent image formed in this way is
A developing means to which a positive bias approximately equal to the surface potential E of the unexposed portion is applied performs development.

As a result, the toner T1 having a positive charge adheres to the exposed portion PH, which has a relatively low potential, and a first toner image is formed. The area where this toner image is formed is the positively charged toner T.
Does the potential increase by DUP due to the attachment of 1?
Normally, it does not have the same potential as the unexposed area.

In process (2), the surface of the image carrier on which the first toner image has been formed is charged again by the charger.

As a result, a uniform surface potential E is obtained regardless of the presence or absence of toner T1.

In process (2), a second image exposure is performed on the surface of this image carrier to form an electrostatic latent image.

In process (2), toner T1 is
A toner T2 different from the first toner T2 is developed to obtain a second toner image. Note that the toner T2 also has a positive charge.

Thereafter, the same process is repeated a necessary number of times to obtain a multicolor toner image on the image carrier. A multicolor image can be obtained by transferring this to a transfer material and fixing it by heating or applying pressure.

FIG. 3 is a layout diagram of the components of a conventional apparatus for forming a multicolor image using the above process.

In FIG. 3, a document 5 is kept in close contact with an image information input section 2 by a document presser plate 4. The image information input section 2 converts the image information of the document 5 into an electrical signal including a color signal. The image information converted into a 1-ki signal is digitized by the record data forming section 3 and becomes record data separated into signals of predetermined color components.

The image exposure sections 21 and 22 form a latent image on the image carrier 1 according to recording data using laser beam scanners. In an example of eight developing devices 31, 32, 33, and 34 each containing one type of toner among yellow, magenta, cyan, and black, it is assumed that the developing device 31 contains toner of cyan toner. The following description will be made assuming that the developing device 32 stores magenta, the developing device 33 stores yellow, and the developing device 34 stores black. The pre-transfer exposure lamp 41 and the pre-transfer charger 13 perform pre-exposure and pre-charging to create a state that facilitates transfer. The charge removal lamp 42 and the charge removal electrode 15 remove residual charges from the image carrier 1 after the transfer to the transfer material P. The cleaning device 51 removes residual toner from the image carrier 1 and makes the image carrier 1 ready to form a latent image of the next image information.

The chargers 11 and 12 are used to uniformly apply charges to the surface of the image carrier 1. The above action is performed on the image carrier l.
This is done in synchronization with a predetermined rotational speed.

The transfer pole 14 is an electrode that transfers the image formed with toner on the image carrier to the transfer material P, and the separation fi 16 is an electrode that transfers the image formed with toner on the image carrier 1.
This is a device that separates the transfer material P from the surface of the transfer material P. Fixing device 61
is transferred onto the transfer material P and fixes the toner. A conventional multicolor image forming apparatus having the above-mentioned functional configuration will be described in more detail based on the configuration diagram of the conventional apparatus shown in FIG.

In the above configuration, the charger 11 and the image exposure section 21 constitute a latent image forming means 21', and the charger 12 and the image exposure section 22 constitute a latent image forming means 22'.

Also, image carrier 1, developing devices 31 to 34, pre-transfer charger 13, pre-transfer exposure lamp 41, transfer pole 14, separation pole 1
6, the fixing device 61, and the like constitute a visible image forming section 28.

The optical information of the original 5 is transmitted to the filter B by the image information input unit 2.
, three photosensors 23, 2 through G and R
4 and 25. As a result, the color signal I8.
Same I. and the same IN are divided into three color signals and input to the recording data forming section 3. The recording data forming section 3 performs shading correction, gamma correction, enlargement, reduction, etc., and then performs masking and UCR processing to form data of four color (yellow, magenta, cyan, black) components. Masking and UCR processing are performed to ensure consistency between the reading characteristics of the image information input section 2 and the recording characteristics of the printer section 26.
Value or multi-value recording data DY, DM, Da, and DK are formed and output. Recorded data DY, same DM
, same. Both of the DK and DK are outputted in parallel as time-series signals. That is, the yellow component, magenta component, cyan component, and black component of a certain pixel on the image are output at the same time. Switches Sl and S2 are for recording data DY and D.
Which of M, Da and DK is the latent image forming means 21?
This is a selector for selecting whether to transfer the data to ' and 22'. These switches Sl and S2 are selected by a switch S1 which is switched in response to a switching signal from the CPU 9, and the recorded data (DH or Dc) is transferred to a latent image forming means (for example, a laser beam scanner) 21', where a latent image is immediately formed. will be held.

On the other hand, the data (
DY or D) is temporarily stored in the shift register 6. In the shift register 6, the image carrier 1 is connected to the latent image forming means 21.
When a time period equal to the time required to rotate the distance between ' and 22' has elapsed, the stored recording data is transferred to the latent image forming means 22'. As a result, the recorded data is delayed and outputted to the latent image forming means 22' by a time corresponding to the distance. Therefore, the latent image forming means 21'
The latent image formed by the latent image forming means 22' can accurately align the positions of the color-separated images. In the visible image forming section 28, the formed latent image is developed, transferred to a transfer material P shown in FIG. 3, and fixed, thereby completing one copy.

(Problems to be Solved by the Invention) However, when attempting to continuously form multiple copies of images from the same original using the above image forming apparatus,
The image information input section 2, recorded data formation section 3, and other sections must be operated for each copy, which may shorten the lifespan of the elements and parts that make up these sections, or reduce the amount of power needed to operate them. There was a period when consumption increased. Further, since copying time is proportional to the number of copies, there is a problem in that copying takes a long time when a large number of copies are made. In particular, in the above apparatus, even in the case of monochrome image copying using one color toner, the image information input section 2 and the recorded data forming section 3 must all be operated for each copy, which means that the above-mentioned components must be operated. and parts life,
There is a problem in that it is wasteful in terms of both power consumption and time required.

Therefore, in order to solve the above-mentioned problems in the case of monochrome image copying using one color toner, the inventors of the present invention have invented the structure shown in FIG. 5, and the applicant of the present invention is currently applying for the invention.

The configuration in FIG. 5 differs from the configuration in FIG. 4 in that a feedback circuit is provided from the output point of the shift register 6 to the input side, and
The difference is that a switch S5 is provided to change over whether the input to the shift register 6 is the recording data from the recording data forming section 3 or the feedback signal.

When trying to continuously copy multiple monochrome images, use the CP
The switch S5 is connected to the contact a by U9, and the image information input section 2 and the record data forming section 3 operate, and the record data from the record data forming section 3, for example DY
is input to the shift register 6 via switch S2 and switch S5. After the data for one copy is input to the shift register 6, the switch S5 is connected to the contact point to form a feedback circuit in the shift register 6. The storage capacity of the shift register 6 is set to be able to store recording data for one copy.

When a feedback port/path is formed in the shift register 6 with such a capacity, the recorded data Dy for one copy that is once input is circulated, and the same recorded data DY is repeatedly and continuously output from the output of the shift register 6. It will be output. This repeatedly output recording data DY is transferred to the latent image forming means 22'.
By adding the latent image to the image carrier 1, a latent image can be continuously formed on the image carrier 1 at a repetition period determined by the storage capacity of the shift register 6. On the other hand, the recorded data forming section 3
Since it is no longer necessary to operate after outputting the recording data DY for one copy, the operation can be stopped together with the image information input section 2.

In this way, it is possible to avoid shortening the lifespan of these parts and wasteful power consumption due to operating the image information input section 2 and record data forming section 3 for each copy, and it is also possible to shorten the time required to copy a large number of copies.

However, even in the device of the pending invention, when recording a large number of single-color identical images in succession, it is possible to repeatedly output recording data from the shift register 6 to form an image, but the size of the gvit image Regardless of the timing, the readout time for one copy of recorded data in the shift register 6 (one cycle time of data) is determined by the number of storage cells from the signal input terminal to the signal output terminal of the shift register 6 (clock pulse as constant).

However, since the number of memory cells of the shift register 6 is set to the maximum document image size that can be processed by this image forming apparatus, even when recording data of a small document image, the number of storage cells is set to the maximum document image size that can be processed by the present image forming apparatus. Since the repetition period is the same as the time, the recording time has the disadvantage that it requires the same length of time regardless of the size of the document.

An object of the present invention is to solve the above-mentioned problems of the inventive device by using a tapped shift register in which an intermediate tap is provided from the middle of a memory cell column as a shift register,
When the dimension of the document in the sub-scanning direction is smaller than the dimension corresponding to the total storage capacity of the shift register in the shifted direction,
Taps can be selected to operate cyclically in a memory column with a small capacity relative to its size, thereby shortening the recording data circulation time and reducing wasted time during continuous recording of monochromatic images. The purpose of the present invention is to provide an image forming apparatus that can extend the life of the image forming apparatus and reduce power consumption.

(Means for Solving the Problems) The present invention has the following means configuration to achieve the above object. That is, the image forming apparatus of the present invention includes an image information input unit that reads image information, a recorded data forming unit that performs signal processing on the read image information to form recorded data of one or more predetermined image information components, and a rotatable an image carrier, one or more latent image forming means for forming a latent image on the image carrier based on recorded data of the recorded data forming section;
In the image forming apparatus, the image forming apparatus includes one or more developing means for developing the latent image with toner to form a toner image, and a transfer means for transferring the toner image on the image carrier onto a transfer material. Upon receiving the recorded data from the forming means,
a tapped shift register that delays the data and outputs it to the latent image forming means, or stores the recorded data and repeatedly outputs the recorded data to the latent image forming means; The data may be directly guided to the latent image forming means, the data from the recorded data forming means may be delayed by the tapped shift register and then sent to the latent image forming means, or the recorded data for one copy may be transferred to the tapped shift register. After the signal is input to the register, the signal input from the record data forming section is cut off, and the output signal of the tapped shift register is returned to the input side, circulated, and repeatedly outputted to the latent image forming means. a switching means; in the case of said circulation, an input side tap and/or a switching means;
or a tap switching means for selecting an output side tap;

The above-mentioned tapped shift registers include not only those in which taps are provided in one component, but also those in which small-capacity shift registers are connected in series and taps are provided from the connection point.

(Function) Hereinafter, the function of the image forming apparatus of the present invention having the above means configuration will be described. For convenience of explanation, the latent image forming means is the first one.
A case will be described in which two latent image forming means, a latent image forming means and a second latent image forming means, are provided.

In either recording mode, the image information obtained by the image information input section is converted into an electrical signal and becomes recording data separated into predetermined image information components by the recording data forming means. When recording a multicolor image, recording data having a predetermined image information component from the recording data forming section is directly sent to the first latent image forming means in the latent image forming means, and other predetermined image information components are sent directly to the first latent image forming means of the latent image forming means. The recording data having the image data is delayed by a tapped shift register by a time corresponding to the time required for the image carrier to reach the second latent image forming means from the first latent image forming means to form the second latent image. A multicolor image is formed on the image carrier. In the case of monochromatic high-quality recording, recording data is directly sent from the recording data forming means to the latent image forming means to form a high-quality image on the image carrier. In the case of continuous recording of the same monochromatic image, after the recording data for one copy is input to a predetermined input terminal of the tapped shift register, the signal input from the recording data forming means is cut off, and the output signal of the tapped shift register is is returned to a predetermined input end of the tapped shift register, circulated and outputted repeatedly, and this output signal is repeatedly inputted to the latent image forming means to form a latent image on the image carrier, and the developing means develops the toner. Form an image.

The above recording mode selection is performed by an external operation using a switching means for switching the circuit connection of the tapped shift register and a tap switching means for selecting the tap of the tapped shift register. This is done according to the dimensions in the scanning direction (rotation direction of the image carrier).
A tapped shift register has an intermediate tap extending from the middle of the column in the direction in which the signal of the memory cell column is shifted.
The shift amount can be selected by selecting the intermediate tap. Therefore, if the dimension of the original image in the sub-scanning direction is small, a tap with a small shift amount is selected, and the repetition period when circulating the recording data can be shortened, so that many continuous copies of the same monochrome image can be recorded. The recording time can be shortened.

(Example) Hereinafter, an example of the present invention will be described based on the drawings. 1st
The figure is a configuration diagram of an embodiment of the present invention.

This will be explained based on FIG. The optical information of the original 5 is transmitted to the image information input unit 2 through filters B, G, and R.
It is input to the three photosensors 23, 24, and 25, and becomes three color signals of color signals In, Io, and IR.
The three color signals are input to the recording data forming section 3. The recorded data forming section 3 performs shading correction, gamma correction,
Masking and UC after signal processing such as enlargement and reduction
R processing is performed to form data for four color (yellow, magenta, cyan, black) components. Masking and UCR processing are performed to ensure consistency between the reading characteristics of the image information input section 2 and the recording characteristics of the printer section 26. Multivalue recording data Dy, same DM, same. and forms the same DK and becomes output data. Recorded data DY,
Same Dm, same. Both of the signals and the DK are time-series signals and are output in parallel with each other.

That is, the yellow component, magenta component, cyan component, and black component of a certain pixel on the screen are output at the same time. Switches S1 and S2 are for recording data DY, DM, and DC.
and a switch for selecting which of the DKs to be transferred to the latent image forming means 21' and 22'. Recording data (DM or Dc) selected by switch S
is a latent image forming means (for example, a laser beam scanner) 21'
A latent image is formed immediately after the image is transferred to the computer.

On the other hand, the recording data (DY or DK) selected by the switch S2 receives the recording mode signal and is sent to the CPU 9.
The latent image forming means 22' is transmitted to the latent image forming means 22' through different routes depending on the recording mode according to the switching signal outputted from the latent image forming means 22'.

In the multicolor image recording mode, the switch S3 is connected to the e side by switching from the CPU 9, and the recording data (Dy or DK) is temporarily stored in the tapped shift register 7. The tapped shift register 7 transfers the stored recording data to form a latent image when a time period equal to the time required for the image carrier 1 to rotationally move the distance between the latent image forming means 21' and 22' has elapsed. The information is transferred to the means 22'. As a result, the recording data is delayed and outputted to the latent image forming means 22' by a time corresponding to the above-mentioned interval. Therefore, the positions of the images formed by the latent image forming means 21' and 22' can be precisely aligned. In the monochrome single recording mode, when the switch S3 is connected to contacts a and d, the recording data from the recording data forming section 3 is directly transferred to the latent image forming means 22'.
The time from image input to output is shortened.

In the monochrome same image continuous recording mode, the input tap of the tapped shift register 7 is switched by the switch S4 according to the size of the original image, and the switch S3 is contacted and connected to the same e by the switching signal from the CPU 9. , the image information input section 2 and the record data forming section 3 operate to transfer record data, for example DY, from the record data forming section 3 to the switch S2.
and tapped shift register 7 via switch S3.
input to. After the recorded data for one copy is input to the tapped shift register 7, switch S3
is connected to contacts C and F to cut off the signal input from the recording data forming section 3, and the output signal of the tapped shift register 7 is fed back to the input end of the tapped shift register 7, circulated, and repeatedly output. The output signal is transferred to the latent image forming means 2.
By repeatedly inputting data to 2', it is possible to continuously record a large number of monochromatic images in a shorter time than with conventional devices.

Note that the recording mode switching means is not limited to the circuit consisting of the switches S3 and S4 described above, and various circuit configurations can be considered to achieve the same purpose. Furthermore, although the above embodiment has exemplified the case where a tapped shift register whose input taps are switched is used, the same objective can be achieved even when a tapped shift register whose output taps are switched is used.

(Effects of the Invention) As explained above, in the image forming apparatus of the present invention,
A tapped shift register and tap switching means are provided between the output end of the recording data forming means and the input end of the latent image forming means,
A switching means for switching the circuit connection operates a tapped shift register as a delay means when recording a multicolor image to form a multicolor image, and when recording a monochrome high quality image, converts the recording data from the recording data forming means into a latent image. In addition to being able to directly send it to a forming means to form a high-gradation image,
Furthermore, when recording the same monochromatic image continuously, if the dimension of the document in the sub-scanning direction is smaller than the maximum copyable dimension, the tap of the tapped shift register is selected by the tap switching means, and the time required for the recording data to circulate is set. Since it can be made shorter, there is an advantage that when recording a large number of monochromatic images in succession, the time can be further shortened compared to the case where a shift register without taps is used. As a result, it is possible to provide an image forming apparatus that has the advantages of increasing operating efficiency, extending the lifespan of its components, and reducing power consumption.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, and FIG.
The figure is an explanatory diagram of potential changes on the image carrier, Figure 3 is a layout diagram of the components of a conventional apparatus, Figure 4 is a block diagram showing the configuration of a conventional apparatus, and Figure 5 is a diagram of an apparatus with high-speed continuous copying function. FIG. 2 is a block diagram showing the configuration. 1... Image carrier, 2... Image information input section, 3... Record data forming section, 4...
・・Document holding plate, 5・・・Document, 6・・・・
...Shift register, 7...Tapped shift register, 9...CPU, 11.12...
...Charger, 13...Pre-transfer charger, 1
4...Transfer pole, 15...Removal electrode, 1
6...Separation pole, 21.22...Image exposure section, 21', 22'...Latent image forming means, 2
3,24゜25...Photo sensor, 26...
... Printer section, 28... Visible image forming section,
31...C developing device, 32...M developing device, 33...Y developing device, 34...
... BK developing device, 41 ... Pre-transfer exposure lamp, 42 ... Static elimination lamp, 51 ...
...Cleaning device, 61...Fuser,
Sl, S2. S3゜S4. S...Switch,
I B, I a, I R...color signal,
P...Transfer material, D c, D w, D
Y, D *・・・Recorded data, B, G, R・
·····filter. An explanation of how Yoshihiro Hachiman, the agent and patent attorney, was requested to become a historical figure

Claims (1)

[Claims] an image information input unit that reads image information; a record data forming unit that performs signal processing on the read image information to form record data of one or more predetermined image information components; a rotatable image carrier; and the record data. one or more latent image forming means that forms a latent image on the image carrier based on recorded data of a forming section; and one or more developing means that develops the latent image with toner to form a toner image. and a transfer means for transferring the toner image on the image carrier onto a transfer material, wherein the image forming apparatus receives record data from the record data forming means and delays the recording data to the latent image forming means. a tapped shift register for outputting or storing the recorded data and repeatedly outputting the recorded data to the latent image forming means; The data from the recording data forming means is delayed by the tapped shift register and sent to the latent image forming means, or the recording data is formed after the recording data for one copy is input to the tapped shift register. a switching means for selecting either to cut off the signal input from the tapped shift register, return the output signal of the tapped shift register to the input side, circulate it, and repeatedly output it to the latent image forming means; An image forming apparatus comprising: tap switching means for selecting a side tap and/or an output side tap;