JPH0652930B2 - Data transmitter - Google Patents

Description

TECHNICAL FIELD The present invention relates to a data transmission device that transmits data to a plurality of terminals.

[Conventional technology]

Conventionally, when obtaining a hard copy of a color image, for example, in a color printer such as a thermal transfer system or an electrophotographic system, usually Y (yellow), M (magenta), C (cyan), BK
A hard copy of a full-color (all colors) image is obtained by a so-called subtractive color mixture method in which (black) color phenomenon materials are sequentially superposed. Then, in this case, it is necessary to accurately superpose the Y image, the M image, and the C image on the recording medium (recording paper).

Therefore, when the color image information read by the color image reading device (color reader) is sequentially printed in real time, or when the image memory is not provided,
A synchronous control method for superimposing color images between a color reader and a color printer was required.

FIG. 8 is a sectional view for explaining the outline of a color copying machine, which has a color reader 51 in the upper part and a color printer 52 in the lower part. The color reader 51 reads color image information of an original for each color by a color separation means described later and a photoelectric conversion element such as a CCD (charge storage element) and converts it into an electric digital signal. In addition, the color printer 52
Is an electrophotographic laser beam printer which reproduces a color image for each color according to the digital image signal and transfers the color image to the recording target a plurality of times in a digital dot form for recording.

First, the outline of the color reader 51 will be described.

Reference numeral 53 is a document, and 54 is a document scanning unit for scanning the document 53. The document scanning unit 54 includes a rod array lens 55, a unity color separation line sensor (color image sensor) 56, and an exposure lamp 57.
Reference numeral 58 is a wiring code of the document scanning unit 54, 59 is a cooling fan, and 60a is a signal processing board, which performs signal processing for sending the output of the color image sensor 56 to the image processing section 60b through the wiring code 58.

When the document scanning unit 54 moves and scans in the direction of arrow A in the drawing to read the image of the document 53 on the document table, at the same time, the exposure lamp 57 in the document scanning unit 54 is turned on,
Reflected light from the original 53 is guided by a rod array lens 55 and is condensed on a color image sensor 56 which is a color information reading sensor.

Reference numeral 61 is an actuator provided under the original scanning unit 54, and 62a and 62b are position sensors.
The scanning position of the document scanning unit 54 is detected via the actuator 61. The position sensors 62a and 62b are composed of micro switches and the like.

Next, the outline of the color printer 52 will be described. Reference numeral 71 denotes a scanner, which is a laser output unit for converting an image signal from the color reader 51 into an optical signal, a polygon mirror 72 having a polyhedron (for example, a dodecahedron), a motor (not shown) for rotating the polygon mirror 72, and an imaging lens 73. And so on. A reflection mirror 74 changes the optical path of the laser light.
Reference numeral 75 is a photosensitive drum, 76 is a primary charger, 77 is a separation static eliminator, 78 is a full-surface exposure lamp, and 79 is a cleaner section for collecting the untransferred residual toner. Reference numeral 80 is a pre-transfer charger, and these members are arranged around the photosensitive drum 75.

A developing device unit 81 develops the electrostatic latent image formed on the surface of the photosensitive drum 75 by laser exposure. Reference numeral 82 denotes a screw, which conveys the developing material. 83 _Y , 83 _M , 8
3 _C and 83 _BK are toner hoppers, which hold preliminary toner. 84 _Y , 84 _M , 84 _C , and 84 _BK are developing sleeves, which are in contact with the photosensitive drum 75 and perform linear development. The developing unit 81 includes the screw 82 and the toner hopper 83.
_Y , 83 _M , 83 _C , 83 _BK and developing sleeve 84
_Y , 84 _M , 84 _C , 84 _BK , and these members are arranged around the rotation axis P of the developing unit 81. For example, when a yellow toner image is formed, yellow toner development is performed at the position shown in this figure, and when a magenta toner image is formed, the developing unit 81 is rotated about the P axis in the figure to expose the toner image. The developing sleeve 84 _M in the magenta developing unit is arranged at a position in contact with the drum 75. cyan,
Block development works similarly.

A transfer drum 85 transfers the toner image formed on the photosensitive drum 75 onto the recording paper. 86 is an actuator plate that detects the moving position of the transfer drum 85. A position sensor 87 detects that the transfer drum 85 has moved to the home position by contacting the actuator plate 86. Reference numeral 88 is a transfer drum cleaner, 89 is a paper pressing roller, and 90 is a transfer charger.

On the other hand, reference numerals 92 and 93 denote paper feed cassettes that store recording paper. Paper feed rollers 92a and 93a feed recording paper. Timing rollers 94a to 94c set timings for feeding and carrying. Reference numeral 95 denotes a paper guide, which causes the fed recording paper to be carried by a gripper and wound around the transfer drum 85, and then shifts to an image forming process.

A peeling claw 96 removes the recording paper from the transfer drum 85 after the image forming process is completed. A conveyance belt 97 conveys the removed recording paper. An image fixing unit 98 fixes the recording paper conveyed by the conveyor belt 97. The image fixing section 98 is composed of a pair of thermal pressure rollers 98a and 98b.

Next, the image forming operation will be described with reference to FIGS. 9 (a) and 9 (b).

9 (a) and 9 (b) are operation explanatory views for explaining the image forming timing.

In these figures, T is the leading edge of the original 53. The light reflected from the document surface of the document 53 is guided to the rod array lens 55 of the document scanning unit 54, and the color image sensor 56 sequentially reads the image.

On the other hand, an actuator 61 is attached to the lower portion of the document scanning unit 54, and a position sensor (DTOT sensor) 62a and DTOP fixedly installed in the main body are installed.
A position signal is obtained at the position of the sensor 62b. Normally, the stop is performed based on the output signal of the DTOP sensor 62a and the output of the document reading DTOP sensor 62b.

In the color printer 52, an image is written at the laser exposure position PH on the photosensitive drum 75. Further, a position sensor (ITOP sensor) 100 fixedly installed on the main body and an actuator plate 86 attached to the transfer drum 85 are arranged on the periphery of the transfer drum 85, and the front end of the recording paper on which the toner image is transferred. Are carried by the gripper at the tip a of the actuator plate 86. Further, the length of the circumference of the actuator plate 86 is fixed at l + α, and the DTOP sensor 62a in the color reader 51,
It is a little longer than 62b.

First, when the tip end a of the actuator plate 86 on the transfer drum 85 rotating at a constant speed in the arrow direction (clockwise direction) is detected by the ITOP sensor 100, the scanning movement of the document scanning unit 54 is started. (See FIG. 9 (a)) When the document scanning unit 54 comes to the DTOP sensor 62b, the document is read, and accordingly the synchronous memory is
The color-separated images that have been read from the leading edge T of the document are stored line by line.

On the other hand, on the color printer 52 side, when the rear end b of the actuator plate 86 on the periphery of the transfer drum 85 is detected, the reading from the beginning of the above-mentioned synchronous memory is performed from the time when the rear end b is detected, and thus the exposure by laser light modulation is performed. The image writing to the drum 75 is started (see FIG. 9 (b)).

Thus, when the ITOP sensor 100 detects the tip a of the actuator plate 86 of the transfer drum 85, the exposure scanning of the document scanning unit 54 is started, and when the DTOP sensor 62b detects the tip T of the document 53, the document is scanned. While the image reading and the writing to the synchronous memory are started, the rear end b of the actuator plate 86 is at the ITOP sensor 1
At the same time as the detection of 00, the image data is read from the synchronous memory.

[Problems to be solved by the invention]

However, when a plurality of color printers 52 are connected to one color reader 51, the following problems occur.

That is, in the color printer 52 and the image forming apparatus that winds the recording paper around the transfer drum 85 to transfer the image, the ITOP for determining the write start position of the transfer drum 85 is used.
A sensor 100 is provided, and after an image formation command is input, an initial setting operation such as pre-rotation is performed in preparation for normal image formation. At this time, if the image writing start signal sent from the ITOP sensor 100 to the color reader 51 varies from printer to printer, there is a problem in that printing cannot be performed in parallel on a plurality of printers.

The present invention has been made to solve the above problems, and determines the deviation amount of the operating states of a plurality of terminals to which the same data should be transmitted, and determines the deviation amount of the operating states of the plurality of determined terminals. By setting the timing of transmitting data to each of the plurality of terminals according to, and by transmitting the data to each of the plurality of terminals at the set timing,
Without exactly matching the operating status of multiple terminals,
An object of the present invention is to obtain a data transmission device capable of transmitting data in parallel to a plurality of terminals whose operation states are deviated, and shortening the time required to transmit the same data to a plurality of terminals. .

[Means for solving problems]

A data transmission device according to the present invention provides a determination unit that determines deviation amounts of operating states of a plurality of terminals, and a plurality of terminals according to the deviation amounts of operating states of the plurality of terminals that are determined by the determining unit. It has a setting means for setting the timing of transmitting data to each, and a transmitting means for transmitting data to each of the plurality of terminals at the timing set by the setting means.

[Action]

According to the present invention, when the timing for transmitting the data to each of the plurality of terminals is set by the setting means in accordance with the deviation amount of the operating state of the plurality of terminals determined by the determining means, the transmitting means is set. It is possible to transmit data to each of the plurality of terminals at the specified timing and transmit the data to the plurality of terminals in a short time.

〔Example〕

FIG. 1 is a block diagram for explaining the configuration of a data transmitting apparatus showing an embodiment of the present invention, and shows a case where it is applied to an image forming apparatus to which a plurality of color printers can be connected, the same as FIG. The same symbols are attached to the items.

In the figure, reference numeral 1 denotes an analog processing unit, which outputs a cyan signal (C signal), a green signal (G signal), a yellow signal (Y signal) from a chip of the color image sensor 56 for each pixel, (C-G) signal, R (Y-
G) Create a signal. Since the output potential of the signal processed by the analog processing unit 1 changes linearly with respect to the concentration, it is converted into a digital signal by an 8-bit A / D converter (not shown) in preparation for high-speed processing. Reference numeral 2 is a jumper memory which synthesizes the digital signals processed by the analog processing unit 1 and connects them to the video signals of 5 channels in the horizontal synchronizing signal section. An image processor unit (IPU) 3 performs a shading correction process for correcting the light distribution of the video signal transmitted from the jumper memory 2 and a masking process for correcting the tint. After each processing is completed, the IPU 3 converts the image signal VIDEO of 8 bits or less and outputs the image signal VIDEO to the cascade unit 7. Reference numeral 4 denotes a synchronization signal processing unit which synchronizes the signal processing of the image processing unit 60b in response to a command from the control unit 5. An operation unit 6 inputs various image processing modes.

The serial unit 7 is composed of a control unit 8, a synchronization control unit 9 and a serial memory 10, and the control unit 8 outputs the image writing permission signals ITOPA and ITO sent from the ITOP sensors 11a and 12a of the color printers 11 and 12, respectively.
For example, the image writing permission signal I
When TOPA precedes the image writing permission signal ITOPB, the image reading start signal RSTART is sent to the color reader 5 in synchronization with the image writing permission signal ITOPA.
1 to the control unit 5. The synchronization control unit 9 counts the time from the reception of the image writing permission signal ITOPA to the reception of the image writing permission signal ITOPB by the horizontal synchronization signal RHSYNC generated by the color reader 51, and synchronizes with the image writing permission signal ITOPA. Image signal VIDEO written in the serial memory 10
Of the color printer 12 to the synchronous memory 12b is controlled. When the image writing permission signal ITOPA is later than the image writing permission signal ITOPB, the above description is reversed, and when the image writing permission signal ITOPA and the image writing permission signal ITOPB are the same, the image writing permission signal ITOPA or The image signal VIDEO is written in the synchronous memories 11b and 12b in synchronization with the image write permission signal ITOPB.

Reference numerals 11c and 12c denote synchronization control units, which are color printers 11,
12 horizontal synchronizing signals PHSYNC and an image carrying clock PCLK are generated, and the synchronizing memories 11b and 12b are generated.
The image signal VIDEO stored in the semiconductor laser 11e of the scanner 71 is read out by the gradation control circuits 11d and 12d and known gradation processing such as dither processing is performed.
The on / off signal is output to 12e. Reference numerals 11f and 12f denote horizontal synchronizing signal (BD) sensors, which are semiconductor lasers 11e and
The laser beam sent from 12e is received before image writing, and the BD signal is output to the synchronization control units 11c and 12c.

FIG. 2 is a block diagram for explaining the configuration of the control unit 8 shown in FIG. 1. Reference numerals 21a and 21b are latches formed of, for example, flip-flop circuits, and the synchronization signal processing unit 4 is provided.
Image write permission signals ITOPA, ITO transmitted from the ITOP sensors 11a, 12a of the color printers 11, 12 according to the horizontal synchronization signal RHSYNC transmitted from
PB is latched and the latch pulses LA and LB are output to the latches 22a and 22b in the subsequent stage. Reference numeral 23 is a counter, which is a horizontal synchronization signal RHSYNC sent from the synchronization signal processing unit 4.
Is counted and a count signal is output to the latches 22a and 22b. 24 is a comparator, which is a latch 22a, 22
The output of b is compared and the image write enable signal ITOPA,
Determine the output order of ITOPB and compare output C
A, CB and CC are output to a CPU (central processing unit) 31 described later when the following conditions are satisfied.

That is, the comparator output CA is output when the image write permission signal ITOPA is output before the image write permission signal ITOPB, and the other comparator outputs CB and CC are "0". Also, separate output CB
Is output when the image write permission signal ITOPB is output before the image write permission signal ITOPA,
The other comparator outputs CA and CC are "0". Further, the comparator output CC, the image writing permission signal IT
This signal is output when OPA and the image writing permission signal ITOPB are output at the same time, and other comparator outputs CA,
CB becomes "0". Reference numerals 25a and 25b denote buffers which hold the outputs of the latches 22a and 22b and their inverted outputs. An adder 26 calculates a relative difference between the buffers 25a and 25b and outputs addition value signals ADDE and ADDD to the control unit 8 and the synchronization control unit 9.

The counter 23 is cleared by the image reading start signal RSTART sent from the control unit 8.

FIG. 3 (a) is a block diagram for explaining the sending control operation of the image data VIDEO stored in the duplicate memory 10 shown in FIG. 1. The same parts as those in FIG. ing.

In the figure, reference numeral 31 is a CPU which is provided in the control unit 8 and receives the comparator outputs CA, CB, CC and the addition value signal ADDE. Reference numerals 41a, 41b and 42 denote gate circuits, which are the image signals VIDEO stored in the serial memory 10 or the direct image signals VID sent from the IPU 3 according to the comparator outputs CA, CB and CC.
EO is gated, and the video signal VIDEO is output to the gate circuits 43 and 44 in the subsequent stage. Control signals inputs a and b are output from the CPU 31 to the gate circuits 43 and 44 based on the comparator outputs CA, CB and CC, and the duplicate memory 10 is provided.
The output of the image signal VIDEO stored in the memory or the direct image signal VIDEO sent from the IPU 3 to the synchronous memories 11b and 12b of the color printers 11 and 12 is controlled according to the color mode signal. 45a and 45b are AND gates, which are the first image writing permission signals IT
When the later of the OPA and the image writing permission signal ITOPB is output from the color printers 11 and 12, the transmission of the image reading start signal RSTART for starting the image reading of the color reader 51 is masked. AND gate 45
An image reading start signal RSTAR is provided at one end of a and 45b.
The control signals c and d for masking the transmission of T are the CPU 3
1 and the outputs of the AND gates 45a and 45b are output to the OR gate 46.

FIG. 3B is a detailed block diagram for explaining the relationship between the synchronization control unit 9 and the multiple memory 10 shown in FIG.
The same reference numerals are given to those having the same functions as those in FIG.

In this figure, ADCOT is an address control unit, which is an L stage of the n-stage line buffer memory which constitutes the multiple memory 10.
BM1 to LBMN are set as the first image writing permission signal I
For the line determined by the difference between TOPA and the image write enable signal ITOPB, that is, the horizontal synchronization signal RHSYN
The LBM of the line buffer memory for a predetermined line is counted according to the difference between the first image writing permission signal ITOPA and the image writing permission signal ITOPB after counting with C.
Select 1 to LBMN. VICOT is an image control unit that counts the horizontal synchronization signal RHSYNC and
LBM1 of the line buffer memory in which the address control unit ADCOT selects the image signal VIDEO transmitted from
~ Write to LBMN. The address control unit ADCO
T secures a memory area for n + 1 (1 <n + 1 <N) lines when the number of differential lines between the first image write enable signal ITOPA and the image write enable signal ITOPB is n.

In the data transmitting apparatus configured as described above, the setting means (in this embodiment, the address control unit A shown in FIG. 3B) is used.
When the timing for transmitting data is set to each of the plurality of terminals in accordance with the deviation of the operating state of each of the plurality of terminals by the DCOT), the transmitting means (in the present embodiment, the duplicate memory 10 and The gate circuits 41a, 41b, 42 shown in FIG. 3 (a) are configured to transmit data to each of a plurality of terminals at a set timing, and transmit the data to the plurality of terminals in a short time. It is possible.

Next, the image forming control operation based on the difference between the first image writing permission signal ITOPA and the image writing permission signal ITOPB will be described.

When a print key (not shown) is pressed from the operation unit 6, an operation command is sent from the control unit unit 5 of the color reader 51 to the color printers 11 and 12 to the control unit units 11g and 12g. As a result, the color printers 11 and 12 start a predetermined pre-rotation process, and the ITO
The first image writing permission signal ITOPA and the image writing permission signal I output from the P sensors 11a and 12a.
The CPU 31 shown in FIG. 3A controls the control signals c and d so as not to output the slower TOPB to the color reader 51.
Is output to AND gates 45a and 45b. On the other hand, IT
The first-time image writing permission signal ITOPA and the image writing permission signal ITOPB output from the OP sensors 11a and 12a are also output to the latches 21a and 21b shown in FIG. The first-time image writing permission signal ITOPA and the image writing permission signal IT are applied to the latches 21a and 21b.
The horizontal synchronization signal RHSYNC generated by the synchronization signal processing unit 4 of the color reader 51 before the OPB is transmitted is input to the clock terminal CK. When the first image write permission signal ITOPA and the image write permission signal ITOPB are input, the latches 21a and 21b output latch pulses LA and LB to the subsequent latches 22a and 22b.
While the horizontal synchronizing signal RHSYNC is being sent to the latches 22a and 22b, the count signal sent from the counter 23 is being sent out, and the count value that has been counted in synchronization with the latch pulses LA and LB is sent to the comparator 24.
Output to. In response to this, the comparator 24 compares the respective count values, and the image writing permission signal ITOP
If it is determined that A and the image writing permission signal ITOPB are before or after, and if the image writing permission signal ITOPA is output before the image writing permission signal ITOPB, the comparator output CA is output to the CPU 31 and the buffer is output. It is output to 25a. On the other hand, the output of the latch 22b is sent to the buffer 25b, and on the basis of this, the adder 26 outputs the addition value signal ADD as a difference.
It outputs E and ADDD to the CPU 31 and the synchronization control unit 9. In response to this, the address control unit AD of the synchronization control unit 9
COT is the line buffer memory LB in the dual memory 10
A predetermined line of M1 to LBMN is supplied with the image signal VIDE.
Reserved for O storage. Next, the control unit 8 causes the first image writing permission signal for starting image reading, that is, the preceding image writing permission signal ITOP.
A is output to the color reader 51 at a predetermined timing. As a result, the color reader 51 causes the exposure lamp 57 to
Is turned on, the scanning of the document scanning unit 54 is started, and the reflected light is color-separated by the color image sensor 56.
The image signal VIDEO, which is processed by the IPU 3 in synchronization with the horizontal synchronizing signal RHSYNC and is processed by the preceding color printer 11, is directly sent to the synchronizing memory 11b line by line via the multiplex unit 7. On the other hand, the added value signal ADDE (line difference) calculated by the adder 26
Is output to the address control unit ADCOT of the synchronization control unit 9 and, for example, it is determined that there is a difference of 3 lines,
Since the address control unit ADCOT secures a memory area for the line buffer memories LBM1 to LBM4 (the number of lines + 1 line) in the multiplex memory 10, the image of each line transmitted in synchronization with the horizontal synchronization signal RHSYNC. The signal VIDEO is transferred to the line buffer memories LBM1 to LBM
BM4, for example, line buffer memories LBM4, LB
Write to M3, LBM2, and next horizontal sync signal RHSY
Line buffer memory LBM when NC is input
The image signal VIDEO1 for one line written in 4 is read, and in parallel with this reading, the image signal VIDEO of the fourth line is written in the line buffer memory LBM1.
4 and then line buffer memory LBM3
The image signal VIDEO2 for one line written in is read, and in parallel with this reading, the image signal VIDEO5 of the fifth line is written in the line buffer memory LBM4.
Is sequentially performed in synchronization with the horizontal synchronization signal RHSYNC. The image signals VIDEO written in the line buffer memories LBM1 to N are sequentially written in the synchronous memory 12b of the delayed color printer 12, image formation is performed in the first color mode, and the image write permission signal ITOPA is sent from the color printer 11. The image is output again, and image formation in the second color mode is executed in the same manner as described above. That is, the color mode designated by the operation unit +1 and the image writing permission signal ITOPA and the image writing permission signal ITOPB for one time are set to the AND gates 45a and 4a.
5b, the preceding image writing permission signal ITO
Image reading is performed in synchronization with the PA, and the image signal VIDEO for each line is transferred to the color printer 11 as described above.
12 is sent.

In addition, the image signal VIDEO is the color printers 11 and 12
Of the horizontal sync signal PHSYNC and the image signal VID generated by the sync control units 11c and 12c in the color printers 11 and 12, respectively.
The processing speed is converted by the clock signal PCLK for carrying EO.

Next, the operation of the control units 5, 8, 11g, 12g shown in FIG. 1 will be described with reference to FIGS.

FIG. 4 is a flow chart for explaining the operation of the control unit 5 in the color reader 51 shown in FIG. In addition,
(1) to (9) show each step.

First, the initial display routine is executed (1), and the start of the color reader 51, the duplex unit 7, and the color printers 11 and 12 is waited until it is OK (2). Waiting for the print key (not shown) to be pressed (3), and when it is pressed, the control unit 5 causes the control unit 8 of the multiple unit 7 and the color readers 11, 1
A prescan operation command is sent via the second control units 11g and 12g (4), and a drive start signal is sent from the control units 11g and 12g to the rotary drive system of the transfer drum to start the pre-rotation. As a result, the ITOP sensor 11a,
12a from the image writing permission signal ITOPA. ITOP
Waiting for B to receive (5), if NO, it is judged whether or not the image write permission signals ITOPA and ITOPB are output within a fixed time (6), and if NO, go to step (5). If YES is returned, the error processing routine is executed (7).

On the other hand, in step (5), the image writing permission signal ITOP
When A and ITOPB are sent, the sequence according to the color mode of the tandem unit 7 is executed (8), it is judged whether the color mode sequence is completed (9), and if NO, the process returns to step (8). , YES, return to step (2).

FIG. 5 is a flow chart for explaining the operation of the control unit 8 of the multiplex unit 7 shown in FIG. Note that (1)
~ (9) shows each step.

First, the initial display routine is executed (1), and it is judged whether the start of the color reader 51, the duplex unit 7, and the color printers 11 and 12 is OK (2), and the error processing routine which is NO (3) is executed. ), If YES, waits for a print key (not shown) of the operation unit 6 to be pressed (4),
When pressed, the first image writing permission signal ITO
Masking is performed by AND gates 45a and 45b so that the later one of PA and ITOPB is not sent to the color reader 51 (5). Next, it is judged whether or not the calculated difference line number exceeds the line buffer memory number of the multiplex memory 10, that is, LBMN (6), and if YES, write permission of the image output from the color printers 11 and 12 is permitted. The control unit 11g of the color printers 11 and 12 sends a command to move the output position of ITOPA and ITOPB.
, 12g (7) and returns to step (2), and if NO, outputs the first image writing permission signal, for example, the preceding image writing permission signal ITOPA to the color reader 51, and also corresponds to the color mode. Image signal VID
Turn on the gate circuits 43 and 44 to output EO to the color printer 11 or the color printer 12 (8)
. Then, it is judged whether or not the designation of the gate circuits 43 and 44 is completed (9), and if NO, the process returns to step (8) and Y
If ES, return to step (4).

FIG. 6 is a flow chart for explaining the operation of the control units 11g, 12g of the color printers 11, 12 shown in FIG. In addition, (1) to (10) indicate each step.

First, execute the initial display routine (1), wait for the multiple unit 7 to be connected to the color printers 11 and 12 (2), and if so, wait for the end of warm-up.
(3) If the toner has been warmed up, the absence of toner is checked, and the development colors that cannot be formed by the color printers 11 and 12 are stored in the internal memories (RA of the control units 11g and 12g).
M) (4). Next, waiting for the print key to be pressed (5), if the print key is pressed, the pre-rotation processing is executed (6), and as described above, the image writing permission signals ITOPA and ITOPB control the serial unit 7. It is sent to the unit 8. Next, the image writing permission signal I
The number of differential lines of TOPA and ITOPB is the duplicate memory 10
Image write enable signal ITOPA, IT that is output when the maximum number of lines of the line buffer memory of
It is judged whether or not a command for moving the OPB output position is output (7). If YES, move the transfer drum to that output position (8), and return to step (5). If NO, specify the color mode. The process is executed (9), and it is judged whether the image formation based on the color mode designation process is completed (10). If NO, the process returns to step (9), and if YES, the process returns to step (2).

FIG. 7 is a timing chart of the signals of the respective parts shown in FIG. 1, and the same parts as those in FIGS. 1 to 3 are designated by the same reference numerals.

In this figure, VSYNCA and VSYNCB represent vertical synchronizing signals, VIDEOOA and VIDEOOB are image signals, and the image signal A is synchronized with the vertical synchronizing signal A and the image signal A is synchronized with the color printer 11 and the image signal B is synchronized with the vertical synchronizing signal B. Is sent to the color printer 12. The image signal A and the image signal B are the same image signal, and the image signal B is sent from the duplicate memory 10.

In the above embodiment, the difference line is measured when the first image write permission signals ITOPA, ITOPB are sent, and the first image write permission signal ITOPA,
Control is performed so that main image formation is not performed at the time of sending to ITOPB, and the difference line is not changed until the image formation of the set color mode is completed, but each time the image formation of a predetermined color is completed. Needless to say, if the difference line measurement control is interrupted and the difference line is corrected again, the accuracy of image shift prevention can be further improved.

Further, although the above embodiment has been described by taking the color printer as an example, the present invention can be easily applied to an image forming apparatus that performs multiple transfer by winding transfer paper.

Further, in the above embodiment, the case where the image signal VIDEO read by the color reader 51 is sent to the color printers 11 and 12 has been described. However, up to N printers can be connected, and when N printers are connected. Is N
It suffices to provide +1 multiple unit 7.

〔The invention's effect〕

As described above, according to the present invention, it is possible to determine the deviation amount of the operating state of a plurality of terminals to which the same data should be transmitted,
Since the timing of transmitting data to each of the plurality of terminals is set according to the determined amount of deviation of the operating state of the plurality of terminals, and the data is transmitted to each of the plurality of terminals at the set timing, It is possible to send data in parallel to multiple terminals with different operating states without exactly matching the operating states of the other terminals, reducing the time required to send the same data to multiple terminals. There is an effect that can be.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of a data transmission device showing an embodiment of the present invention, FIG. 2 is a block diagram illustrating the configuration of the control unit shown in FIG. 1, and FIG. FIG. 3 is a block diagram for explaining the transmission control operation of the image signal stored in the multiplex memory shown in FIG. 1, and FIG. 3B is the relationship between the synchronization control unit and the multiplex memory shown in FIG. 3A. FIG. 4 is a detailed block diagram for explaining the operation of the control unit, and FIGS. 4 to 6 are flowcharts for explaining the operation of each control unit shown in FIG.
FIG. 7 is a timing chart of the signals of the respective parts shown in FIG. 1, FIG. 8 is a sectional view for explaining the outline of the color copying machine, and FIGS. 9 (a) and 9 (b) are operations for explaining the image forming timing. FIG. In the figure, 1 is an analog processing unit, 2 is a jumper memory, and 3 is I.
PU, 4 is a synchronizing signal processing unit, 5 is a control unit, 6 is an operating unit, 7 is a multiple unit, 8 is a control unit, 10 is a multiple memory, 11, 12 are color printers, 11a, 12
a is an ITOP sensor, 11b and 12b are synchronous memories, 1
1c and 12c are synchronous control units, 11f and 12f are BD sensors, 11g and 12g are control units, and 51 is a color reader.

Claims (1)

[Claims] 1. A data transmitting apparatus for simultaneously transmitting the same data to a plurality of terminals, the determining means determining a deviation amount of operating states of the plurality of terminals, and the plurality of determining means determined by the determining means. Setting means for setting the timing of transmitting data to each of the plurality of terminals according to the deviation amount of the operating state of the terminal, and data for each of the plurality of terminals at the timing set by the setting means. A data transmission device comprising: a transmission unit for transmitting.