JPH0736645A - Copy system - Google Patents

Abstract

PURPOSE:To provide a copy system which makes plural copies in a short time and reduces the cost by transferring the same read picture data to plural picture output devices and making plural picture output devices take charge of designated numbers of copies respectively. CONSTITUTION:In a constitution example where one picture input device and plural picture output deices 2 are provided, the same input picture data is transferred to plural picture output devices 2M, and n picture output devices take charge of plural copies respectively. In this system, each subsystem is not provided with a page buffer, and a color copy is realized with a line buffer of several lines. Consequently, the same picture data read by a picture read means provided in the picture input device 1 is transferred to plural picture output devices 2, and picture output devices 2M can take charge of designated numbers of copies respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying system provided with a plurality of image output devices for one image input device, and more particularly, a plurality of copies can be copied in a short time and at a low cost. Copying system that can be implemented

[0002]

2. Description of the Related Art A conventional copying machine has one image input means,
Generally, one image output means is provided, and in order to copy a plurality of copies in such a copying machine in a short time, both the image input means and the image output means are speeded up, or The digital copying machine is provided with an image buffer for at least one page, and is realized by means such as speeding up of the image output means. On the other hand, in a SCSI system that realizes various functions by connecting a plurality of subsystems so that they can communicate with each other via a transmission line, when performing the above processing, the subsystem connected to the transmission line is used. In addition to applying the above method to the image input device and the plurality of image output devices, it is possible to share the output by providing each of the image output devices with an image buffer for at least one page.

[0003]

In a copying system such as a SCSI system in which an image input device and an image output device are connected via a transmission line, as described above, the time required for copying a plurality of copies is reduced. This can be realized by increasing the speed of the output device or by providing a plurality of image output devices. According to the latter method, when there are a plurality of output request sources,
The latter method is efficient because it has advantages other than shortening the time for copying a plurality of copies, such as being able to deal with it by parallel processing. However, in the above-described conventional technique, each image output device needs to include an image buffer for at least one page, and thus the cost and size of the device cannot be avoided. In other words, the capacity of the image buffer for one page that should be provided in the image output device is, for example, 4 colors of YMCK, 16 pixels / mm, 4 gradations, and A4 size in order to cope with the colorization that has become widespread in recent years. Assuming that the memory capacity is 16 MB, the memory capacity will be extremely large, and due to advances in semiconductor technology, large-capacity RAM has come to be offered at a low price. As a result, cost and size are increased.

[0004]

SUMMARY OF THE INVENTION The present invention solves the problems of the prior art as described above, and in a copying system having a plurality of image output devices for one image input device, it is possible to copy a plurality of copies in a short time. It is an object of the present invention to provide a copying system that can be realized and can realize cost reduction.

[0005]

[Means for Solving the Problems] To achieve the above object,
The present invention relates to a copying system including at least one image input device and a plurality of image output devices that are connected to each other via a transmission line so that each device includes only a line buffer as an image data buffer. The same image data read by the image reading unit provided in the image input device is transferred to each of the plurality of image output devices, and the designated number of copies are shared by the plurality of image output devices. What to do, when the designated number of copies is larger than the number of the plurality of image output devices to be shared, the image input device reads the same document a plurality of times, and each time, the read image data is read by one or a plurality of images. It is configured to transfer to the output device, the reading operation of the image input device for copying a plurality of copies, and the images of the plurality of image output devices. Forming operation synchronously to initiate, and the above reading operation, any one in the plural image output devices
It is characterized in that the image forming operation of the table is synchronized every time the image formation of one color or one sheet is completed, and the image reading operation and all the image forming operations are performed in parallel.

[0006]

In the copying system having at least one image input device and a plurality of image output devices connected to each other through the transmission path so as to be able to communicate with each other, each of the above devices serves as an image data buffer. The same image data read only by the image reading means provided in the image input device, which has only a line buffer, is transferred to each of the plurality of image output devices, and a specified number of copies are made. When the designated number of copies is greater than the number of image output devices to be shared, the image input device reads the same original document a plurality of times, and each time the read image data is read by one or A configuration for transferring to a plurality of image output devices, and further, a reading operation of an image input device for copying a plurality of copies and a plurality of image output devices The respective image forming operations are started in synchronization, and the reading operation and the image forming operation of any one of the plurality of image output devices are synchronized every time one color or one image is formed, Image reading operation,
Since all the image forming operations are performed in parallel, it is possible to copy a plurality of copies in a short time by providing an image buffer with an extremely small capacity.

[0007]

Embodiments of the present invention will now be described in detail with reference to the drawings. First, here, as a copying system to which the present invention is applied, as shown in FIG. 7, an image input device 1 and an image output device 2 which are communicably connected to each other via a transmission line 9.
Then, in the copying system including the control processing device 3, a copying system capable of color copying by only providing a line buffer of one line or several lines as an image buffer will be described. As shown in FIG. 1, the image input device 1 includes at least an image reading unit 11 for reading an original image by dividing it into pixels, and a first communication control unit 10, and the image output device 2 includes at least an image forming unit 21. And the second communication control unit 20, and the control processing device 3 includes an operation unit 31 and a communication control unit 30. Furthermore, the above three devices are as shown in FIG.
Although they are mechanically separated from each other, they have a structure in which the functions of the system can be satisfied by exchanging data and instruction information with each other via the transmission path 9. Further, in the figure, the control processing device 3 also has a separate structure, but other two
A structure in which either one of the two devices is housed in the housing is also possible.

The configuration and operation of each device will be described below. As shown in FIG. 1A, the image input device 1 includes an image reading unit 11, a basic image processing unit 12, an extended image processing unit 13,
It comprises a communication control means 10 and further an image reading means 1
1 includes an AD converter 116 and a shading correction circuit 117.
A sampling position deviation compensating circuit 118 is provided.
The structure of the image reading means 11 is as shown in FIG. In FIG. 2A, 111 is a first carriage, 112 is a color imaging device, 113 is a carriage home sensor, and 114 is a motor. Original image scanning is performed as follows. The first carriage 111 is a normal carriage home sensor 11
It stands still immediately above 3 and stands by, and when it receives a reading start command, it drives the motor 114 to start scanning in the right direction. Carriage 111 is home sensor 113 along with this scanning.
When it goes out of the detection range of, this position is stored as a scanning reference position and used as a calibration reference point. Further, the communication control means 10 calculates an optimum acceleration plan to achieve the arrival time to the image front end 119 and the required accuracy of speed, and calculates the cycle of the step pulse train for driving the motor 114 and the generated timing time. Thereafter, the carriage speed is driven by this pulse train, and the time to reach the image front end 119 and the desired constant speed scanning are achieved as expected.

After passing the calibration reference point, the image pickup device 112 separates one line of main scanning of each color into, for example, 16 pixels / mm in terms of the original image, reads it by sampling, regardless of the speed.
After passing the reference point, the white reference plate is first read, converted into an 8-bit digital value by the A / D converter 116, and stored in the shading correction circuit 117. The shading correction is effectively performed on the image data read thereafter. Next, when the carriage 111 reaches the leading edge 119 of the original image, the imaging device 112 outputs an analog voltage corresponding to the RGB reflected light in pixel units from the original image, and the A / D converter 116 outputs an 8-bit digital signal, that is, 256 bits. The tone is quantized and output to the basic pixel processing means 12 as a color separation digital value for each pixel. In this way, all of the original images are read in sequence, and when the carriage 111 reaches the right end, the motor 114 is rotated in the opposite direction, returned to the home position, stopped, and prepared for the next scan.

FIG. 3 is a block diagram showing the configuration of the communication control means 10. In the figure, 101 is a microprocessor, 102 is RAM, 103 is ROM, 104 is a timer counter, 105 is a sync signal generator, 106 is a DMA controller, 107 is a FIFO, and 108 is a SCSI controller. The communication control means 10 includes a control processing device 3 and an image output device 2.
And the image reading operation is controlled based on the command and the image data is transferred to the image output device or the like via the transmission line 9 (see FIG. 7). Organically control the components of.

In the color copying mode, when the image output device 2 adopts the CMYK frame sequential image forming system, one original image needs to be scanned four times, and the image input device 1 makes one scanning. A signal corresponding to each of CMYK is sent out for each color. As shown in FIG. 1B, the image output device 2 includes an image forming unit 21, a recording control circuit 23, and a second communication control unit 20. The second communication control means
Reference numeral 20 is a hardware configuration similar to that of the first communication control means 10 in the image input apparatus 1. The second communication control means 20 communicates with the control processing device 3 and the image input device 1, receives image data transferred from the image input device 1 based on the command, and transfers the data to the recording control circuit 23. At the same time, all the constituent elements in the image output device 2 are organically controlled. Further, in FIG. 2C showing the mechanism of the image output device, 211 is a laser diode, 212 is an fθ lens, and 21
3 is a mirror, 214 is a photoconductor drum, 215 is a paper feed roll, 2
16 is an intermediate transfer belt, 217 is a primary transfer corotron, 218
Is a secondary transfer corotron, 219 is a charged scorotron, 220
C, 220 M, 220 Y, and 220 K are cyan, yellow, magenta, and black developing devices, 221 is a cleaner, and 222 is a cleaner.
Is a conveyor belt, 223 is a fixing roll, 224 is a drive motor,
225 is an image position detecting means. The image output device 2 forms and outputs a full-color visible image for the CMYK color image data input to the second communication control means 20.

In the above arrangement, when the image forming cycle is started, the photosensitive drum 214 is first rotated counterclockwise by the drive motor 224. As the photosensitive drum rotates, C (cyan) latent image formation, C toner image formation, M
A latent image is formed, an M toner image is formed, a Y latent image is formed, a Y toner image is formed, a K latent image is formed, and a K toner image is formed. Finally, a toner image is formed on the intermediate transfer belt in the order of CMYK. To be First, C image formation is performed as follows. The charging scorotron 219 uniformly charges the photosensitive drum 214 with negative charges to -700 V by corona discharge, and then the laser diode 211 performs raster exposure based on the C signal.

The recording signal is image data input to the second communication control means 20, and the recording control circuit 23 controls the light emission of the laser diode 211 for each input pixel based on the recording signal. More specifically, when the signal is the highest density pixel, the laser is emitted for the entire main scanning width, when the signal is a white pixel, the laser is not emitted at all, and when it is an intermediate density, it is emitted for a time proportional to the density data. Let When the raster image is exposed in this way, the exposed portion on the peripheral surface of the photosensitive drum 214, which is initially uniformly charged, loses electric charge in proportion to the amount of exposure light and forms an electrostatic latent image. To be done. Subsequently, the C toner charged to have a negative polarity by stirring in the developing device 220 C is adsorbed to an uncharged portion, that is, an exposed portion on the photosensitive drum 214, and a C visible image similar to a latent image is formed. It is formed. In the toner image formed in this manner, when the photosensitive drum rotates counterclockwise and reaches a position facing the primary transfer corotron 217, the intermediate transfer belt 216 is driven at the synchronous speed while being in contact with the photosensitive drum. Is transcribed on.

In order to make the next magenta (M) image formation coincident with and overlap the cyan (C) image formed on the intermediate transfer belt 216, a synchronization signal is formed prior to the formation of the M latent image. That is, the reading start control information is sent to the image input device 1. This timing is the time when the image position detecting means 225 detects the registration C toner mark image which is slightly preceded by the effective C image (start position of the C image) when forming the C image. Is.
As shown in FIGS. 1 (c) and 2 (b), the control processing device 3 includes a third communication control means 30, an operation unit.
31, a system control means 32, an external storage device 33, and the like. Further, the system control means 32 includes a copy control means 321, a facsimile communication means 322, a print control means 323, an intelligent image processing means 324, an external connection connector 325, and the like. I have it.
The third communication control means 30 has the same hardware configuration as the first communication control means 10 in the image input device 1. The control processing device 3 has a function of integrally controlling the entire copying system, and is connected to another subsystem constituting the present system, for example, the image input device 1 or the image output device 2 via a transmission line 9, Controls the entire system while sending and receiving control information (commands and information necessary for protocols) and image data. The operation unit 31 includes a key input unit and a display unit, and has a function of outputting a message to the operator and inputting various instructions.

In the SCSI system shown in this embodiment, control information is communicated at some times and image data is transferred at some times via a common transmission line. By operating the separated image input device 1 and image output device 2 in parallel while cooperating, a speed equivalent to that of a conventional general copying machine in which a reading unit and an image forming unit are integrated. In order to achieve the above, it becomes important how to realize synchronization between image reading and image formation by using the above-mentioned general-purpose communication means,
The synchronization is especially important when forming a color image as in the present system.

The parallel operation of image input and image output by this system will be described below with reference to FIGS. 1, 2, 3, 4, 5, and 6, focusing on synchronization. 4 is a flowchart showing a communication control procedure, FIG. 5 is a flowchart showing an operation in the image input apparatus 1, and FIG. 6 is a flowchart showing an operation in the image output apparatus 2. In this embodiment, the SCSI system is used as the communication means for transferring the control information and the image data on the same transmission path. In this copying system, in the initial state, the control processor 3 is an initiator defined by SCSI, and the image input device 1 and the image output device 2 are targets ([SCU] shown in FIG. 4 is a control processor). It represents an initiator). And
The operation flow described below is such that when each device is in the above-mentioned state and is in the information transfer phase defined by SCSI, the operator operates the control processing unit (hereinafter abbreviated as SCU) 3 It starts when the copy key in the operation unit 31 is pressed.

The operator designates the number of copies, the paper size, and the density if necessary, while instructing copying by using the copy key. Regarding the paper size, the SCU 3 can automatically determine the paper size based on the document size information detected by the image input device (hereinafter abbreviated as SCN) 1. The SCU 3 issues a Mode Select command to the SCN 1 via the transmission line 9 (indicated by (2) in FIG. 4 is the destination target), whether or not to use the ADF, whether to increase the density or to reduce the lightness. , SCN1 selectable functions / performances such as whether the reading resolution is at the photograph level or not (S401). The operation flow shown in FIG. 4 exemplifies the case where an ADF (automatic document feeder) is used.

Then, the SCU 3 outputs a Define Window command to the SCN 1 if necessary, and sets the scanner reading area (S402). Then, a Mode Select command is issued to the image output device (hereinafter abbreviated as PRN) 2 to specify a paper feed tray (paper size), a paper discharge bin and the like if necessary (S403). The SCU 3 obtains the information regarding the paper feed tray (paper size) from the operator or the SCN 1 as described above. Further, the information regarding the discharge bin is obtained from the operator.

Next, with respect to SCN1, Object Position
A command is issued, a document set in an ADF (not shown) is set on the platen 115 (FIG. 2A) (S404), a Copy command is issued to the PRN2, and the paper feed tray 226 (FIG. The transfer paper set in c)) is conveyed to the position of the register (S405). At this time,
After sending the Copy command, PRN2 is made to be an initiator for SCN1. That is, PRN2 is SCU3
It is a target for SCN1 but an initiator for SCN1.

By the way, in the above control, SCU3
Is an initiator because the operation unit is provided on the control device 3. That is, not only the copying system is configured as described above by using the subsystems such as the image input device 1, the image output device 2, and the control processing device 3 that configure the present system, but also various other subsystems are used. Although a system having a function can be configured, in such a case, it is preferable to provide the operation unit only on the control processing device 3 in terms of operability, cost, expandability, and uniformity. Therefore, the first reason why the SCU3 is the initiator is that the copying instruction needs to be input from the SCU3 because the operation unit is integrated with the SCU3. Another reason is that since the SCU3 has a role of controlling various subsystems, it is more suitable to use only the SCU3 as an initiator when the system is not operating. On the other hand, hereinafter, in the parallel operation of image reading and image formation to be executed, PRN2 for directly communicating with PRN2 and SCN1 will be referred to as an initiator.
PRN2, which became the initiator, is Tes against SCN1
t Unit Ready command is issued to check whether SCN1 is ready to start reading (S40
6). Here, the state in which SCN1 can start reading is
Place the original on the platen 115 at the specified position and
Carriage 111 is at home position (Carriage home sensor 113
It is in the standby position directly above).

Upon receiving a response from the SCN1 stating that "reading can be started", the PRN2 drives the motor 224.
Is started (S601), the image forming sequence control is started (S602), and the process waits until the reference point is detected (S603).
This reference point corresponds to the C toner mark image detected by the image position detecting means 225. When the C toner mark image is used as the reference point as in the above-described embodiment, when the first cyan (C) image is formed, the reading operation of SCN1 is started without synchronizing with the reference point,
When forming the second and subsequent images, the reading operation of the second and subsequent colors of SCN1 is started in synchronization with the detection of the C toner mark image formed on the intermediate copying belt 216 during the cyan image formation. However, it is also possible to provide a permanent mark (reference point) on the intermediate transfer belt 216 as in the operation flow shown in FIG. In this case, the first color and the second and subsequent colors are synchronized with this permanent reference point and the reading operation of the SCN 1 is started, so that the respective colors can be superimposed on the intermediate transfer belt 216 without error.

In this way, when the reference point is detected, P
The RN2 issues a SCAN command (reading start control information) to the SCN1 via the transmission line 9 (S407, S604), and the SCN1 receiving this starts the motor 114 (S501) and starts the movement of the carriage 111. In this way, the synchronized carriage 111 advances to the reading start position, and the similarly synchronized transfer start position on the intermediate transfer belt 216 is conveyed to the transfer position.

After that, the carriage 111 operates as described above (S502 to 506), moves at a constant speed by the constant motor speed control (S507), and eventually reaches the leading edge 119 of the document (S508).
), When the read data can be transferred (S509), wait for the main scanning counter to reach 0 (S509).
510) Start reading the first reading line.
The main scanning clock frequency that determines the reading speed is set to be almost the same as the main scanning clock frequency that determines the writing speed of the PRN2, but the reading speed can be slightly increased. The speed of sub-scanning (line counting) is synchronized with the speed of main scanning. That is, the motor 11 is used for the main scanning count and the sub scanning.
The number of pulses given to 4 corresponds to the motor 11
When a predetermined pulse is given to 4, the sub-scan (carriage
Move 111) advances by one line. The synchronization-related circuits such as the main scanning counter and line counter are synchronization signal generators.
Included in 105. Similarly, the sub-scanning speed of writing in PRN2 is synchronized with the main scanning speed, and the moving speed of the intermediate transfer belt 216 is also synchronized with the writing speed (main scanning clock frequency) of PRN2.

Therefore, as described above, if the start of reading is aligned with the intermediate transfer belt 216, the first line written on the photosensitive drum 214 will be on the intermediate transfer belt 216 when it is just moved to the transfer position. The position defined as the first line of (1) also moves so as to face the first line on the photosensitive drum. For that purpose, the synchronization at the start and S
The main scanning speed adjustment in CN1 and PRN2 and the synchronization of the main scanning and the sub-scanning are appropriate, and the motor acceleration control plan in SCN1 is appropriate.
It is important that the transfer start timing of image data (read data) to RN2 is appropriate. this is,
This can be realized by configuring the motor 114 with a stepping motor and moving the carriage 111 by a distance proportional to the given pulse. That is, by applying a predetermined pulse to the stepping motor by a predetermined time, the line synchronization (S510) is completed and the buffer (FIFO) 10
The timing to start the transfer to 7 (S511) is SCAN
You can set in advance how long it has been since the command transfer.

To the FIFO 107, as described above,
The read analog signal is input through the AD converter 116 and the basic image processing means 12. That is, the read analog signal is sampled at a predetermined frequency, converted into an 8-bit digital value by the AD converter 116, and then image-processed by the basic image processing means 12, for example, only the upper 2 bits are transferred to the PRN 2. FIFO 107 as data to be
Entered in. The digital value corresponding to each pixel is used in PRN2 to control the writing pulse width of laser light to give gradation, but in a general copying machine, 256 gradations that can be represented by 8 bits are Since it cannot be realized, 8 bits are not required for this information representation. Therefore, in this system, the transfer time via the transmission line 9 is shortened by setting the four gradations represented by 2 bits in accordance with the performance of the writing means, and a general-purpose communication means such as a SCSI bus is used. Even when the data is transferred via, the writing speed can be followed and the parallel processing of the read operation in SCN1 and the write operation in PRN2 is realized.

After sending the SCAN command to SCN1, PRN2 resets the line counter (S605) and resets the transfer counter after a lapse of a predetermined line time (S605).
607), line synchronization is performed in the same manner as SCN1 (S608), S
A Read command is output to CN1 (S408). Above S
As described above, the time from the transmission of the CAN command to the output of the Read command is such that the first line written on the photosensitive drum at the transfer position faces the predetermined position on the intermediate transfer belt 216 after the predetermined time. It is the time that was set.

When SCN1 receives the Read command,
Although the FIFO 107 of the SCN 1 already contains image data for one line to several lines, the amount of stored data can be set (planned) within a certain error range as is clear from the above description. When the read speed is designed to be the same as the write speed, the speed extracted from the FIFO to PRN2 is the same as the write speed, so the read speed may slow down due to an error. The number of lines α is required so as not to overflow from 107. On the contrary, since the reading speed may increase due to an error, in order to prevent the data in the FIFO 107 from becoming empty when the Read command comes line by line or every few lines, Since it is necessary to input β line before the first Read, FIF
O 107 needs to have a buffer of α + β lines. This amount is 2 to 3 lines in this embodiment. In addition, if the reading speed does not exceed the writing speed even if the reading speed varies, the reading speed will be slower than the writing speed by β for the number of lines. Therefore, in this case as well, the required buffer amount is α + β lines. Become.

The Read command from PRN2 to SCN1 is performed in units of one line or several lines. SC
Data transfer to the FIFO 107 (S511) in N1 is line synchronization (S51) regardless of the Read command.
0) is performed. That is, when one line is transferred, the line counter is incremented (S512), and if the reading of a predetermined number of lines is not completed (S513),
The main scan counter is set to 0 to read the next line.
Wait for (S510). When the main scanning counter becomes 0, the carriage 111 (sub-scanning) is advanced by one line as described above, and one line is read again, and the FI
Transfer to the FO (buffer) 107. When the reading of the predetermined number of lines is completed (S513), some subsequent processing is performed (S514 to S516), the rotation of the motor 114 is reversed (S517), and when the motor returns to the home position (S518),
The motor is stopped (S519).

The PRN 2 fetches one line of image data into the buffer in synchronization with the line synchronization (S608) determined by the writing speed (S609), increments the transfer counter (S610), and the recording control circuit 23 stores the data in the buffer. Image data is extracted, and a latent image for one line is formed on the photoconductor drum while controlling the laser pulse width in four steps based on 2-bit data per pixel. If the line count does not reach the predetermined line (S612), the next line is synchronized again and the Read command is issued to SCN1. Note that the flow of FIG. 6 shows an example of issuing the Read command for each line, but it is also possible to issue the Read command for every several lines. The transfer of a predetermined number of lines is completed (S409), the latent image formation on the photosensitive drum is completed for one frame (one color) (S612, S613), and after a predetermined time, the development is completed as described above. To do.

On the other hand, before the latent image formation for one frame is completed, the leading end (first line) for one frame is located at the position determined as the position of the first line of the intermediate transfer belt as described above. After facing each other and the primary transfer is performed as described above, the motor 224 is stopped (S619). Next, image reading and image formation for the next color (magenta M) are performed, and the synchronization by the SCAN command of SCN1 and PRN2 for that purpose is as described above. After the SCAN command is output from PRN2 to SCN1, the above operation flow is repeatedly executed, and the respective colors are superimposed on the intermediate transfer belt. Eventually, when the transfer of the final color to the intermediate transfer belt is completed (S410, S614), the transfer paper is fed (S615), and after being transferred to the transfer paper,
The paper is ejected (S411, S412, S616 to 619) and the motor 22
4 stops (S619).

FIG. 7B is a block diagram showing an embodiment of the present invention, which is an example of a configuration in which one image input device 1 and a plurality of image output devices 2 are provided. As described below, in the present invention, the same input image data is output by a plurality of image output devices 2.
Since a plurality of copy numbers are transferred to M and shared by n image output devices, the specified number of copies can be made in about 1 / n. Moreover, in this system, each subsystem does not have a page buffer, and color copying is realized by the line buffer of several lines as described above.

One method for realizing the above function is as follows.
As shown in FIG. 2C, the image output device 2 is provided with the image position detecting means 225 based on the toner mark so as to synchronously start the image forming operations of the plurality of image output devices and to drive the image output device 2 with a drive motor 224 is not stopped until the copy designated by the operator is completed, and the capacity of the line buffer in the image output apparatus 2 is increased slightly. That is, after the plurality of image output devices 2M are synchronously started to operate, the synchronization between the image output devices 2 is not required, but the image forming speed of each image output device 2 is set to be substantially constant. Every time the copying operation of one color is completed, the image data is periodically transferred from the image input device 1 synchronized with one image output device to the line buffer of each image output device, and the image data is read from the line buffer. It is configured to perform image formation.

In the above description, the reference point is detected by the toner mark regardless of the detection of the reference point on the transfer belt during the first image formation (first color of the first sheet). This is so that the image formation can be started even at the timing. If the permanent mark is used instead of the toner mark, it is necessary to start image formation in synchronization with the reference point from the first image formation, and the line buffer between the image output devices 2 must be started. This is because there is a problem that the timings of reading the image data from are not the same. The reason is that the relative positions of the reference points (permanent marks) between the image output devices 2 are different when the image output devices are stopped.

The present invention will be described in detail below with reference to an operation flow example of the image output apparatus shown in FIG. In the following description, as shown in FIG. 7C, a plurality of image output devices 2
The image output device 2A synchronized with the image input device 1 is abbreviated as PRN2A, and all other image output devices 2B (one in this case) are abbreviated as PRN2B. The starting point S721 of the flow of FIG. 8 is the same as that of the flow shown in FIG.
It matches the S405 Copy command transfer. In FIG. 8, the flow starting from S721 is PRN2A, S
The flow starting from 741 shows the operation flow of PRN2B.

That is, PRN2A is a control processor (hereinafter referred to as S
In response to the Copy command from 3 (abbreviated as CU) (S72
1) Start the motor (S722). Also at the same time PRN2
Immediately thereafter, B also receives a Copy command from SCU 3 (S741) and starts the motor (S742). SCU3
At this time, the number of copies is designated by the Copy command. If the number designated by the operator is 2n, both PRN2A and PRN2B are n sheets, and if the number designated by the operator is 2n + 1, PRN2A is n + 1. Sheet, PR
Let N2B be n sheets. The same number as the PRN 2A is instructed to the image input device (hereinafter abbreviated as SCN) 1. Also, in the above, PRN2A is Cop
The y command may be issued.

Immediately after starting the motor, the PRN 2A outputs a SCAN command to the SCN ₁ (S723), and after a lapse of T ₁ time (S724), resets the transfer counter and performs line synchronization (S725), and at the same time, a READ command to the SCN1. Is transferred (S726). This transfer request (READ command) specifies PRN2A and PRN2B as transfer destinations. In the case of a communication processing system having a broadcast communication function, a broadcast address is designated. On the other hand, the PRN 2B sets the timer T ₂ after starting the motor (S743), resets the line counter (S745), and waits for the reception of image data (S746).

SCN1 is broadcast or individually PR
Image data is transmitted to N2A and PRN2B (S727
, S747). After receiving the image data, the PRN 2A forms an image for one scan on the photoconductor (S729), and performs line synchronization for receiving the next line. On the other hand, PRN2B is S
Until the time set in 743 is up (S74
8) When the image data of a plurality of lines is received and the time is up, line synchronization is performed (S749) and an image of the first line is formed on the photoconductor (S750). In the above, T ₂ is a value slightly larger than T ₁ , and is set so that at least one line of image data is stored in the line buffer of PRN2B at the completion of line synchronization (S749) in consideration of various errors. It

When the PRN 2A completes the formation of a predetermined number of lines (S730), the toner mark (reference point) already formed on the transfer belt is prepared for the image formation of the next color without stopping the motor. Detection is performed (S732), and SCAN is sent to the SCN in accordance with the detection. On the other hand, PRN
2B also completes the image formation number of a predetermined line (S752), similarly, for image formation of the next color, performs the toner mark detection (S754), sets the timer T ₂ when detecting it, forth The process of is repeated. PRN2A, PRN2
In B, when the final color image is formed, secondary transfer is performed on the transfer paper (S733, S754), but if the designated number of copies have not been completed, the same process is repeated from the reference point detection, When the copying of the designated number of sheets is completed, the motor is stopped (S735, S756) and the designated copying operation is completed. It should be noted that, in the above, on the SCN1 side, S
Repeated scanning of the same document in synchronization with the CAN command,
The image data read each time is PRN2A, PRN2
Transfer to B.

Under the above conditions, as a method of sharing the same image data transferred from one image input apparatus 1 among a plurality of image output apparatuses, synchronization between a plurality of image output apparatuses is provided in addition to the above-mentioned means. A means for performing the image forming operation not only when starting the image forming operation but also during the operation may be considered. Further, in the case of color copying, there are two methods for the above synchronization. One of them is a method of performing synchronization for each copy of one color, and the other is a method of performing synchronization for each copy of one sheet. In the case of monochrome copying, it is naturally performed every time one copy is made.

Since the basic operation flow of the method of performing the synchronization on the way is the same as the operation flow of FIG. 8, the operation flow is not shown.
A case of synchronizing each color in color copying will be described.
The toner mark method is also used for the reference point in this method, and the first one-color image formation is performed according to the operation flow of FIG. However, in the method of synchronizing in the middle of the process, since the cumulative error regarding the progress of image formation between the image output devices becomes small, the capacity of the line buffer can be small. That is,
It is possible to reduce T ₂ shown in FIG. 8 (however, T ₁
Greater than). The feature of this method is that, in each image output device, the drive motor 224 is stopped when the reference point is detected for synchronization in the image output device.

In the case of PRN2A, the timing of restarting the drive motor once stopped is after a certain time has elapsed after the stop, or after the stop, all the other image output devices 2B which are sharing the image during copying. This is the time when I received a notification from the company stating that the motor has been stopped. Upon restarting, the PRN 2A outputs a "motor restart command" to the other image output device 2B, and also outputs the SCAN command to the SCN 1 as described above to restart the motor of the SCN 1. That is, the motors of all the image input devices and the image output devices related to copying a plurality of sheets are controlled to be restarted all at once. If the synchronization between the image output devices is performed only when one copy is completed (when the image formation of the final color is completed), a means for determining whether or not the current state is the completion of image formation of the final color is provided. Means may be provided in the RAN, and the determination means may be referred to when the reference point is detected, and the motor may be stopped and restarted as described above only when the image formation of the final color is completed.

[0042]

As described above, according to the present invention,
The same image data read by the image reading means 11 provided in the image input device 1 is transferred to each of the plurality of image output devices 2M, and the designated number of copies are shared by the plurality of image output devices 2M. Therefore, it is possible to perform copying of a plurality of copies in a short time. Further, since only a line buffer is provided as an image buffer for realizing the above, it can be realized at low cost.

[Brief description of drawings]

FIG. 1 is a functional block diagram showing an embodiment of a copying system according to the present invention, where (a) is an image input device, (b) is an image output device, and (c) is a control processing device.

FIG. 2 is a mechanism diagram showing an embodiment of a copying system according to the present invention, in which (a) is an image input device, (b) is a control processing device, and (c) is an image output device.

3 is a block diagram showing a configuration of an embodiment of a communication control means 10 shown in FIG.

FIG. 4 is a flowchart showing an embodiment of a communication control flow of the copying system according to the present invention.

FIG. 5 is a flowchart showing an example of an operation flow of the image input device of the copying system according to the present invention.

FIG. 6 is a flowchart showing an example of an operation flow of the image output device of the copying system according to the present invention.

FIG. 7 is an overall configuration diagram showing a configuration example of a copying system to which the present invention is applied, in which (a) has one image output device and (b) and (c) has an image output device. FIG.

FIG. 8 is a flowchart showing an example of an operation flow of the copying system according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Image input device, 2 ... Image output device, 2M ... Plural image output devices, 3 ... Control processing device, 9 ... Transmission path, 10 ... 1st
Communication control means, 11 ... Image reading means, 12 ... Basic image processing means, 13 ... Extended image processing means, 20 ... Second communication control means, 21 ... Image forming means, 23 ... Recording control circuit, 30 ... Third communication control Means, 31 ... Operating part, 32 ... System control means, 33 ...
External storage device, 105 ... Synchronous signal generator, 107 ... FIF
O, 111 ... First carriage, 113 ... Carriage home sensor, 114 ... Motor, 214 ... Photosensitive drum, 216 ... Intermediate transfer belt, 224 ... Drive motor, 225 ... Image position detection means, 321 ... Copy control means, 322 ... Facsimile communication means, 323 ... Print control means.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koji Kuwata 1-3-6 Nakamagome, Ota-ku, Tokyo Within Ricoh Co., Ltd. (72) Inventor Yasutoshi Hiroe 1-3-6 Nakamagome, Ota-ku, Tokyo Stock company Ricoh

Claims (6)

[Claims] 1. A copying system comprising at least one image input device and a plurality of image output devices connected to each other via a transmission path so that they can communicate with each other. Each of the devices is a line buffer as an image data buffer. Equipped with
The same image data read by the image reading means provided in the image input device is transferred to each of the plurality of image output devices, and the designated number of copies are shared by the plurality of image output devices. Characteristic copying system. 2. When the designated number of copies is larger than the number of the plurality of image output devices shared, the image input device reads the same original document a plurality of times, and one or more read image data are read each time. 2. The copying system according to claim 1, wherein the copying system is configured to transfer to one image output device. 3. The reading operation of the image input device for copying the plurality of copies and the image forming operation of each of the plurality of image output devices are started in synchronization with each other, and the reading operation is performed in the plurality of image output devices. The image reading operation and all the image forming operations are performed in parallel by synchronizing any one of the image forming operations with each time the image formation of one color or one sheet is completed. Claim 1 or 2
The described reproduction system. 4. The copying system according to claim 3, wherein all the image outputs of an image input device and a plurality of image output devices for performing copying of a plurality of copies for synchronization of completion of image formation for one color or one sheet. A copying system characterized in that an image reading operation and all image forming operations are performed in parallel between apparatuses. 5. The copying system according to claim 3 or 4, wherein synchronization is performed every time image formation for one color or one sheet is completed, based on detection of a toner mark. Copy system. 6. The copying system according to claim 4, wherein all of the image output devices are synchronized with the image input device by stopping the drive motor when a toner mark is detected every time image formation of one color or one sheet is completed. The first image output device restarts the motor when a fixed time elapses after the stop or when the motor stop notification is received from all the other image output devices after the stop, and the motors of all the other image output devices are ,
A copying system, wherein the first image output apparatus is configured to restart when it receives a motor restart notification sent at restart.