JPH0876538A - Image forming device - Google Patents

Abstract

PURPOSE: To provide a long-lived and energy conservation image forming device capable of eliminating the need of using a bit map memory by color and special high-speed hardware for high-speed bit map development processing, obtaining such the image quality that is not inferior to the image quality obtained when the high-speed hardware is used, besides, capable of reducing a noise. CONSTITUTION: The device is provided with a photoreceptor 414 for carrying an electrostatic latent image, a means for forming the electrostatic latent image on the photoreceptor 414, developing means for plural different colors for visualizing the electrostatic latent image on the photoreceptor 414 as a toner image, a toner image carrier 415 rotated adjacent to the photoreceptor 414 and for holding the taner image on the photoreceptor 414, a 1st transfer means 416 for transferring the toner image lying on the photoreceptor 414 to the toner image carrier 415, a 2nd transfer means 427 for transferring the toner image lying on the toner image carrier 415 to a recording paper, a fixing means for fixing the toner on the recording paper to the recording paper and a control means 430 for controlling an image forming operation by each color in accordance with the command from an external control means 230.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus capable of superposing a plurality of images, for example, an image forming apparatus such as a color printer, a color facsimile, a color copying machine or the like.

[0002]

2. Description of the Related Art Conventionally, in order to form a color image using an image forming apparatus using an electrophotographic process, a color image is formed by a surface sequential image forming method, and color plate images such as cyan, magenta, yellow and black are formed. They are formed at equal time intervals. Although this technique is efficient for general color image copying, it is not always perfect as a color print output function when viewed from an external device such as a computer. That is, when viewed from an external device, in order to supply the color bit map print data to the image forming apparatus at equal time intervals, a huge print data memory for each color is required, and the bit map expansion process is performed at a special high speed. There is a problem in that it is difficult unless the hardware is provided and the manufacturing cost of the device increases. For example, in Japanese Unexamined Patent Publication No. 4-326372, a bitmap memory for a color being printed and a data for the next color to be printed are developed in parallel into a bitmap, so that two pages of memory are required. With this configuration, it is necessary to finish the development of the image data of the next color into the bitmap memory in sequence by the time the printing of the previous color is completed, so a hardware for high-speed bitmap development processing is required. There is.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above drawbacks of the prior art. The first purpose is not to use a color-by-color bitmap memory or special high-speed hardware for high-speed bitmap expansion processing, and the image quality is not inferior to the case of using these high-speed hardware. Is to provide an image forming apparatus with reduced noise, a long life, and energy saving. A second object of the present invention is, in addition to the first object, to further reduce the noise of the device, extend the life of the device, and save energy. A third object of the present invention is to prevent the image forming time from becoming long even though no special high speed hardware is used. A fourth object of the present invention is to improve the human interface of the image forming apparatus when the above-mentioned first to third objects are achieved. A fifth object of the present invention is to prevent the image forming time from becoming long and to save energy when the above-mentioned first to fourth objects are achieved. A sixth object of the present invention is to prevent the image forming time from becoming long in spite of the simple structure when the fifth object is achieved.

[0004]

In order to achieve the above object, the first means is a photosensitive member carrying an electrostatic latent image, a means for forming an electrostatic latent image on the photosensitive member, and a static image on the photosensitive member. A plurality of different color developing means for visualizing an electric latent image into a toner image, a toner image bearing member which circulates adjacent to the photoreceptor and holds a toner image on the photoreceptor, and a toner image bearing member on the photoreceptor A first transfer means for transferring the toner image, a second transfer means for transferring the toner image on the toner image carrier onto the recording paper, a fixing means for fixing the toner on the recording paper onto the recording paper, a command from an external control means The control means controls the image forming operation of each color in accordance with the above. In order to achieve the second object, the first means is provided with a laser exposure means including a polygon motor as an electrostatic latent image forming means. In order to achieve the third object, the second means is provided with a means for detecting the time from the start of the transfer of the first image data to the start of image formation.

In order to achieve the above-mentioned fourth object, in the above-mentioned first to third means, a means for detecting the time from the start of the transfer of the first image data to the start of image formation, and the first means by the external control means. It comprises a means for receiving the number of times of image data transfer before the start of image data transfer, estimating the end time of the entire image forming process from the time detected by the detecting means, and means for displaying the end time. In order to achieve the fifth object, in the first to fourth means, a means for variably controlling the fixing temperature is provided. In order to achieve the sixth object, in the fifth means, means for detecting a time from the start of transfer of the first image data to start of image formation, and means for receiving the number of times of image data transfer from an external control means. Equipped with.

[0006]

In the above first means, the image data receiving means is
It receives a plurality of image data, which are sequentially and sequentially input from the external control means at regular time intervals via the communication means, one by one.
The printer control means forms an electrostatic latent image on the photoconductor on the basis of the image data received by the image data receiving means, and each image data is designated by the external control means via the communication means. The electrostatic latent image is developed using a color developing device to form a toner image on the photoconductor. This toner image is transferred to the toner image carrier by the first transfer means once for preparing for the reception of the next image data. When the second image data is received by the image data receiving means, the printer control means uses the developing device of the color designated by the second image data as in the case of the first image to form toner on the photoconductor. Create an image. This toner image is transferred to the toner image carrier by the first transfer means, and a superposed image of two image data is formed on the toner image carrier. This image forming process is repeated the number of times instructed by the external control means, and the superposed toner images of a plurality of desired image data formed on the toner image carrier are collectively transferred onto the recording medium by the second transfer means and fixed. The toner is fixed to the recording medium by the means. Here, in the step of forming the superimposed image on the toner image carrier, the circumferential movement of the toner image carrier is stopped after the transfer to the toner image carrier is completed and before the image formation based on the next image data is started. Control the operation so that

In the second means, the printer control means, in the step of forming the superposed image on the toner image carrier, from the end of transfer to the toner image carrier to the start of image formation based on the next image data. During this period, the operation is controlled so that the driving of the polygon motor is stopped. In the third means,
The printer control means detects the time from the start of the transfer of the first image data to the start of the image formation, and the printer control means normally rotates the polygon motor before the start of the image formation by the second and subsequent image data based on the detected time. Control to start up by rotation.

In the fourth means, the printer control section obtains the number of times of image data transfer from the external control means via the communication means before starting the transfer of the first image data, and based on the data transfer number, the first The time from the start of image data transfer to the start of image formation is detected, the end time of the entire image formation process is estimated from the detected time and the number of times of image data transfer, and the end time is displayed. In the fifth means, the printer control section obtains the number of times of image data transfer from the external control means via the communication means before starting the transfer of the first image data, and then sets the temperature of the fixing means to a temperature lower than that during the fixing operation. Control is performed so that the temperature of the fixing unit returns to a predetermined temperature for fixing operation before the recording medium reaches the fixing unit after the transfer of at least the second image data is completed. In the sixth means,
The printer control unit obtains the number of times of image data transfer from the external control unit via the communication unit before starting the transfer of the first image data, and then controls the temperature of the fixing unit to a temperature lower than that during the fixing operation to obtain the first image data. The time from the start of image transfer to the start of image formation is detected, the fixing operation time is estimated based on the detected time and the number of image data transfers, and the recording medium is set so that the fixing operation can be executed promptly when necessary. Before reaching the fixing means, the temperature of the fixing means is controlled to return to a predetermined temperature for fixing operation.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The image forming apparatus according to the present invention will be described in detail below with reference to the embodiments shown in the drawings. In the embodiment of the present invention, the scanner module 200, the printer module 400, and the system control module 600 are used as three basic modules. FIG. 1 is a diagram showing a device configuration example in which the above-mentioned three types of modules are combined. In the figure, a quadrangle is a functional block, HOST is an external computer device, and each line 200S, 400S is a control signal for connecting the modules. It represents a transmission line of an image signal, specifically a SCSI cable.

FIG. 1A shows a so-called scanner device, and FIG. 1B shows an example of system configuration as a printer device. FIG. 1C shows a configuration example of a general copying machine, which can be achieved by connecting one scanner module 200, one printer module 400, and one system control module 600. Here, the system control module 600 integrally controls the above-mentioned two modules to perform a copy function 65 for achieving a copy function.
0CP is incorporated. FIG. 3D shows a triple-reading copying machine, which includes a first scanner module 200-
1, second scanner module 200-2, third scanner module 200-3, printer module 400
And the system control module 600. Here, for example, the scanner module 200-1 is a general A3
If a scanner module having a size of about 200, a scanner module 200-2 having a large size such as A1 size, and a color scanner module 200-3 are provided, various advantages are produced as compared with the case where a dedicated copying machine is installed. Further, the combination and the number of these can be arbitrarily changed according to the usage frequency. In this case, the system control module 600 incorporates a multiple read / copy processing means 650CP2 for integrally controlling the above four modules to achieve a copying function.

Although not shown, a plurality of printer modules can be configured. At this time, the system control module 600 controls the other modules in an integrated manner to achieve a copying function. A continuous recording copy processing means 650CP3 is incorporated. In addition, in this system, the scanner module and the printer module are combined to
It is possible to connect up to a stand.

FIG. 1E shows a scanner module 200,
Printer module 400, system control module 6
00 is a copying machine with copying, facsimile and printer functions. The system control module 600 includes a fourth communication unit 680P for connecting to a host computer 680PC, a printer processing unit 650PR for converting print data received from the fourth communication unit, such as a page description language format, into raster data, and a public unit. Line 680F
Fifth communication means 680F for connecting to C, and color facsimile processing means for decompressing data of a predetermined compression format received from the fifth communication means and compressing original image data read by the scanner module 200 into the predetermined format. 65
0FX is incorporated. Including the internal configuration of these three modules, including the module connection when the system is configured as a copying machine with facsimile and printer functions,
2 and 3 show specific examples in which an automatic manuscript device 280, a film projector 290, a multi-stage paper feeding device 480, and a sorter 490 which are additional modules are added.

Next, the schematic configurations of the scanner module, the printer module, and the system control module will be described. The scanner module 200 includes at least an image reading unit 200rd for reading an original image by dividing it into pixels.
And scanner control means 230, first communication control means 230S
The CSI, the first power demand or supply means 201, and the basic image processing means 300 and the extended image processing means 350.
Is added as needed. Image reading unit 200rd
Is a name given to an aggregate of a plurality of means such as a color image pickup device 207 and an analog / digital converter (hereinafter referred to as an A / D converter) 252.

The printer module 400 includes a storage medium 19
Image forming unit 400img and a second communication control unit 430S that form and output image data as a permanent visible image on the display unit 0.
CSI and first power supply means 401. Here, the image forming portion 400img is a name given to an assembly of a plurality of means, and includes an electrophotographic photosensitive member 414, a charging means 419,
The so-called image forming elements such as the laser exposure unit 427 are included. The system control module 600 includes a third communication control means 630 SCSI and a scanner module 20.
0 for image reading and energizing control, or printer module 400 for image forming and energizing, and system control means 630 which performs at least one function.

As shown in FIG. 3, these three modules have a structure capable of satisfying the function of the system even if they are functionally separated from each other. For example, in a copying machine configuration, the scanner module is packed in a single unit in order to reduce the transport unit weight and simplify the system assembly, while the printer module side has a system control module fixedly mounted on top of it. Make up 1
It uses a method of packing in one box and shipping from the factory. Furthermore, when the module is assembled at the installation location, consideration should be given to the user such as operability and space efficiency, or technical issues such as prevention of electromagnetic radiation, noise immunity, heat dissipation, and mechanical resonance should be addressed. For example, in the case of constructing a copying machine, at least the above three modules are combined with a table or a multi-stage sheet feeding device, but it is preferable to stack these vertically because of space efficiency, and it is preferable that the platen height is 900 mm to 1100 mm. The original manipulating operability can be obtained. Also, by positioning the buttons on the platen surface or slightly below it, an accurate human interface can be realized. Taking these into consideration, the projection shapes of the stacking surfaces of the three modules are made approximately the same so that the upper module is prevented from falling off, and the platen and the operation device surface at the time of stacking are arranged at the above-mentioned positions. From the viewpoint of appearance and compatibility with the electromagnetic environment, the number of cables connecting them has been reduced as much as possible, and the terminal positions have been designed to be close to each other so as to shorten the length.

Next, the structure of the scanner module 200 will be described. Scanner Module 200 of FIGS. 2 and 3
In the figure, 230 is a circuit board on which scanner control means is mounted, 201 is a first power receiving or supplying means, 201P
Is a power plug for connecting a commercial power source or a DC power source, 201
SW is a power switch, 202 is a platen glass, 202
S is the image front end reference position, 202SH is a white plate for shading correction, 202B is a bar code plate for individual identification, 208
Is a first carriage, 209 is a second carriage, 203 is a document illumination lamp, and 204A, B, and C are first and second, respectively.
Third mirror, 205X lens optical axis, 207 color imaging device, 211 carriage sensor, 230S
1, 230S2 are SCSI connectors having the same shape and the same interface on the scanner control means 230, 230F1 and 230F2 are optical fiber connectors for communication with a selective additional device connected to the scanner, and 250 is an original image reading circuit. A mounted circuit board, 300 is a circuit board on which basic image processing means is mounted, and 350 is a circuit board on which extended image processing means is mounted. These are all housed in a scanner module housing indicated by 200 in FIG.

Next, the components of the scanner control means 230 will be described. The configuration of the scanner control means 230 is shown in FIG.
Will be explained. In the figure, 230 CPU is a microprocessor, 230 INT is an interrupt controller, and 23.
0 DV is an input / output circuit for sensors and actuators, 23
0PF is the serial communication unit, 230SYNC is the first
Sync signal generator, 230XTL is the first crystal oscillator, 23
0 DMA is a DMA controller, 230 FIFO is a first-in first-out memory, 230 SCSI is a first communication means including a SCSI controller, 230 BU
S is a bus and 230DC is an image data channel.

Next, the scan control function of the scanner control means 230 will be described. The scanner control means 230 updates the system control module 600 or the printer module 400 with a predetermined protocol, controls the original image reading force based on the command, and outputs the original image data. In addition, all the means in the scanner module 200 and the selective addition devices such as the document feeding device 280 are integrally controlled.

By the way, in a general image system in which the image reading section and the image forming means are separate modules, for example, a light file system, it is usual to have some page buffer memory means between them. However, in such a structure, a time difference is inevitably generated between the image reading and the image formation, and in the copying machine, this time difference has an unfavorable result that the so-called first copy time increases. Therefore, in this embodiment, a method is adopted in which the cost is reduced except for the page buffer, and the image reading and the image forming are performed synchronously, that is, with almost no time difference. 2 is required for synchronization between image reading and image formation.
It includes the meanings of the streets, one is the meaning of the period and the other is the coincidence of the leading phases.

If this synchronization cannot be maintained, it is easy for the former to have a problem that the copy image expands or shrinks, and for the latter, the copy image position on the recording paper cannot be correctly reproduced. I can imagine.
Further, in the color copying system using the CMYK frame sequential image forming printer as in this embodiment, the printer module 400 sequentially superimposes the CMYK images, but it is a page to make it a commercially inexpensive device. It is a good idea to omit the buffer memory. At this time, the scanner module 200 performs the operation four times for one document, for convenience.
It is convenient to send out one of CMYK for each original image operation. Thus, securing the scanning position accuracy of the original image scanning, that is, synchronization, is an important issue in the four color sequential operations. If the synchronization goes wrong, the color plate will be misaligned and the correct color image cannot be obtained.

A method for achieving this problem will be described with reference to FIG. This drawing describes one scan of the original image, and details of two scanning lines are shown in the upper part. First, when the SCAN command is received from the system control means 600, the first carriage 208 always receives the optical axis 205X after t5 hours from the reception.
Reaches the leading edge 202S of the original image, and the sub-scanning speed is set to Vsub.
The control of the first communication control means so as to be as described above is as described above. As a result, the image data is always output after the fixed time t5 from the command reception timing, so that at least the phase synchronization can be maintained. As a device for this purpose, a sensor 211 for detecting a carriage reference position is provided to perform a scan reference position adjustment each time, and the sub-scanning movement amount (movement of the first carriage 208) at one step angle of the stepping motor 210 is performed. Amount) is set to be equal to or less than the sub-scanning line interval. A microstep drive system or the like is used as a motor drive system.

Next, for synchronization of the cycle, the pulse train cycle t generated by the first sync signal generating means 230SYNC.
One main scanning line is read in synchronization with s1, and this is put in the sending buffer 230 FIFO. Further, the receiving side of this data, that is, the system control module 600 in this figure, sequentially takes out the data at substantially the same period as the period ts1. In the copy mode, the data receiving side is the printer module 400, and the above synchronization mechanism is maintained. Therefore, no matter how many times the original image is operated, the original image data will always be sent after a certain time from the command reception,
The positional relationship between the paper and the image (registration) is always maintained correctly, an extra buffer memory is not required at the time of color copying, color plate registration is maintained, and a copy is output quickly. The scanner module 200 basically receives the command from the other two modules, the system control module 600 or the printer module 400.

Another operation of the scanner control means 230 will be described. FIG. 5 is a flow chart showing the operation of the scanner control means 230, and these functions are shown at 230 in FIG.
This is accomplished by the program execution of the CPU microprocessor. Execution program is read-only memory 230ROM
Built into. Reference numeral p201 indicates an operation of turning on the power supply 201SW, and reference numeral p202 indicates a function such as initialization processing, for example, setting initial parameters of various circuit elements, starting a watchdog timer, and moving the carriage 208 to an initial position (above 211). p203 determines whether or not the command input from the terminals 202S1 and S2 has not come within a predetermined time (timeout time).

At p204, the power of the image reading section 200rd is turned off, and the image processing means 300 and the extended image processing means 3 are turned on.
This is a function of reducing the power supply voltage of 50 to the limit at which the data in the register in the circuit element can be held, and contributes to reduction of power consumption during standby and noise of the cooling fan. p205 occurs when the watchdog timer leaves normal execution of the program, and at this time the failure occurrence notification function p205 notifies the system control module 600 of this. p201 is an interrupt vector when a failure occurs in the image reading unit 200rd, the image processing unit 300, and the extended image processing unit 350.
p211 identifies the faulty part and analyzes the factors,
2 notifies the system control module 600 of this.
For example, p213 performs a fail-safe process for avoiding a danger such as a fire when the motor 210 is overheated.

P220 is the SCSI terminals 202S1 and S2
It is an interrupt vector when there is information input to p22.
1 stops the sleep timer. p222 examines the received content and branches it to one of the following five types. First
Is p230 TEST (TEST Unit Rea)
In dy), this is a path for inquiring whether or not the scanner module is manuscript operable, and in p231, the scanner module preparation status including the selective addition devices 280 and 290 is answered.

P290 is a self-diagnosis DI for the scanner
A route when an AG (DIAGnostic) is requested, and is typically a failure occurrence notification function p205, p212
Is requested after the notification of failure, p291 to p293
Performs self-diagnosis and its response process. p240 is an inquiry about various setting modes of the scanner module SENS (MO
In DE SENSe), the currently set operation mode of the scanner module including the selective addition devices 280 and 290 is answered in the processes of p241 to p245.

P250 is various setting mode setting SEL (M
The path at the time of requesting ODE SELECT).
Pair with. Various parameters are set in each routine of p251 to p256. p260 is SCAN or COP
It is a pass at the time of requesting Y, normally once for one original in monochrome processing, three times in the case of RGB processing in color processing, and C
In the case of MYK processing, there are four consecutive requests. At the time of this request, first, the motor 210 is started at p261 and the position counter provided in the memory 230RAM is counted.
In this counter, the first synchronization signal generating means 230SYNC is set to 1
It is incremented by 1 by the sync pulse generated once for the scanning line. In p263, the previously received SC
After 5 hours from the AN or COPY request, the image tip 202S is correctly reached and the mode setting SEL is set in advance.
A drive plan of the motor 210 for aiming at the steady state of the operation speed Vsub set by the (MODE SELECT) request is calculated.

Next, in p264, the reference white plate 202SH is read, shading correction parameter calculation and setting are performed, and it contributes to the shading correction of the subsequent image reading data. Subsequently, the bar code 202B is read at p265, the motor acceleration control is performed at p267, and when the desired speed is reached, the low speed control is switched at p268. p270
Monitors whether or not the count value of the counter reaches the document leading edge position, and when it reaches the position, moves to p267. In p267, the entrance gate of 230 FIFO which is a buffer memory of image data is opened, and preparations are made to receive the image signal from the basic image processing means 300 through the image signal line 300D.

Thereafter, p271 to p274 are a group of tasks for sending the original image data to the 230 FIFO.
At 1, the sync pulse generated every scanning line of the first sync signal generating unit 230 SYNC image is detected. In p272, image data of 4752 pixels for one scanning line is stored in 230 FIFO via the image signal line 300D. At this time, the carriage position counter is incremented in p273. p27
In 4, the loop corresponds to the original image size, for example, in A3 size, 6720 scanning lines, that is, 6720 times are repeated. When the operation for one surface is completed, p275 is 230FI
The entrance gate of the FO is closed, and the color detection result is received from the color document automatic detection circuit 320 in p277. The exchange of such information is performed through the bus 430BUS. Then p27
8 reverses the motor and detects the home on p279,
A configuration operation for resetting the position counter provided in the memory 230RAM is performed, and the motor 210 is stopped at p280. In p223, the sleep timer is activated.

Next, the structure and operation of the image reading unit 200rd will be described. In FIG. 2, 207 is a color imaging device, 252 is an analog / digital converter, and 2
Reference numeral 53 is a shading correction circuit, and 253 is a sampling position deviation compensation circuit. Original 180 is platen 202
The copy surface is on the bottom and the reading start position is on the left edge 20 of the platen.
It is placed so that it becomes 2S. The imaging lens 205 reduces and projects the original image onto the light receiving surface of the image pickup device 207.
The image pickup device 207 is a charge coupled device (CCD) and has a color image pickup function, and is covered with a red filter of 4752 pixels.
Dimensionally arranged R imaging unit, 475 covered with green filter
As a structure in which a G image pickup section having a two-pixel one-dimensional arrangement and a B image pickup section having a 4752 pixel one-dimensional arrangement covered with a blue filter are arranged in parallel in three columns in the main scanning direction (vertical direction to the paper surface of FIG. 3). There is. It is equivalent that the three scanning lines are almost close to each other, specifically, they are at intervals of 4/16 mm in terms of 180 planes of the original image. The scanning direction by this one-dimensional imaging device is called main scanning, and the direction orthogonal to this is called sub-scanning.

The illumination lamp 203 and the first mirror 204A are mounted on the first carriage 208, and the second mirror 204 is mounted.
B and the third mirror 204C are fixed to the second carriage 209. When reading an original image, the first carriage scans from the left end to the right end while maintaining the optical conjugate relationship at the sub-scanning speed Vsub and the second carriage at the speed Vsub / 2 by the original image scanning motor 210 and the drive wire 210W. It is driven (sub-scanning). A stepping motor is used as the motor 210. The sub-scanning speed Vsub is variable from 1/4 to 4 times the reference speed in steps of 1%. An arbitrary speed is selected by a command from another module.

Next, the operation of the image reading section 200rd will be described. FIG. 4 shows a velocity diagram of the image reading mechanism section. The original image scanning will be described with reference to this. The first carriage 208 is stationary and standing by just above the normal carriage home sensor 211. The sensor output at this time is ON. When receiving the scan command SCAN or REQ, the lamp 203 is turned on at t1 and the motor 210 is driven to start scanning in the right direction. Carriage 2 after t2 hours
08 is out of the detection range of the home sensor 211, and the output is OFF. This deviated position is stored as a scanning reference position and used as a calibration reference point for the position. Further, the scanner control means 230 determines the arrival time t to the image leading edge 202S.
5, an optimized speed plan is calculated to achieve the required accuracy of 5 and the speed Vsub, and the step pulse train of the motor 210 is calculated. Thereafter, the carriage speed is driven by this pulse train, and the time to reach the image leading edge 202S and the desired constant speed scanning are achieved as expected. After passing through the calibration reference point, the imaging device 207 moves the lens 2 regardless of the sub-scanning speed.
The image of each color projected by 05 is read in units of main scanning lines,
This is convenient for keeping the charge storage time of the imaging device 207 constant. The main scanning cycle is a pulse train cycle ts1 generated by the first synchronization signal generating means 230SYNC,
The same pulse train is read by the reading means 25 via the bus 230BUS.
Connected to 0.

The first synchronizing signal generating means 230SYNC
Divides the original oscillation frequency of the crystal oscillator 230XTL connected here and outputs it to the bus 230BUS. The total number of pixels of the image pickup device 207 is 4752, and one main scanning line is decomposed into 400 dpi (pixels / inch) in terms of original image, sampled and read, and an analog voltage corresponding to RGB reflected light in pixel units from the original image 180 is output. To do. After that, A / D
It is converted into an 8-bit digital signal by the converter 252, that is, quantized into 256 gradations and passed to the subsequent circuits. After passing the reference point, the white reference plate 202SH is first read at t3, and the 8-bit digital conversion value is stored in the shading correction circuit 253. After that, the read image data is effectively subjected to the jading correction, and the image data is transmitted to the system control module 600.

Next, when the leading edge 202S of the original image is reached at time t5, the image reading section 200rd reads the original image 180 in scanning line units, and color-separated digital data 250 for each pixel.
It is sequentially output as D to the basic image processing means 300 in the next stage. When the carriage 208 reaches the right end and reaches the time t6 at the time when the carriage 208 reaches the right end of the A3 original image 180, that is, the 6720 scanning line segment, the motor 210 is rotated in the opposite direction to return to and stop at the home position 211 for the next scanning. Prepare

Next, the structure of the basic image processing means 300 and the function and operation of each element will be described. In FIG. 2, 3
Reference numeral 01 is a spatial filter circuit, 302 is a variable magnification circuit, 303 is a color processing circuit, 304 is a gradation processing circuit, 310 is an image area automatic separation circuit, and 320 is a color original automatic detection circuit. The spatial filter 301 performs smoothing processing or sharpening processing. Generally, when the original 180 is a halftone dot printed matter, the former process is performed, and when the original 180 includes only characters, the latter process is performed.
The selection is input on the original designation screen of the console 800 or depends on the separation result from the image area automatic separation circuit 310 described later. The scaling circuit 302 shifts the image by 25 in the main scanning direction.
% To 400%. The copy scaling in the sub-scanning direction is achieved by changing the image reading speed (sub-scanning speed).

The color processing circuit 303 subjects the original RGB signal to masking processing to obtain recording color signals C (cyan) and M.
(Magenta), Y (yellow), and K (black) image forming signals. Further, color processing suitable for each of the character image and the grayscale image, for example, so-called adaptive color processing such as pure blackening processing of a black character portion is performed. If necessary, the RGB signals are output as they are to the system control module 600 via the scanner control means 230. The gradation processing circuit 304 performs dither processing from any of the 8-bit CMYK image signals to create a 4-bit recorded image signal. Further, so-called adaptive gradation processing, which is gradation conversion suitable for the character image and the grayscale image, is performed.

The image area automatic separation circuit 310 discriminates a character image portion and a grayscale image portion on one original image on a pixel-by-pixel basis, and the result is identified by a spatial filter circuit 301, a color processing circuit 303,
It is output to the gradation processing circuit 304. The color document automatic detection circuit 320 performs color / monochrome document identification processing. The read original image RGB image data 251D is the spatial filter 30.
1, the image area automatic separation circuit 310 and the color original automatic detection circuit 320 are input and processed in parallel. Basic image processing means 3
The 00 functions are divided into two categories. The first category is a function for supporting image scanning instead of directly manipulating an image signal. For example, an image area separation process for distinguishing and separating a character region and a gradation image region and a document size detection process,
There is color / monochrome document identification processing. In this category of processing, there is processing such as color original / black and white original identification processing in which all original image information on the platen 202 must be checked.

The second category is a process for manipulating an image signal, which is, for example, a spatial filter process, variable-magnification image trimming, image movement, color correction, gradation conversion. These processings are further classified into common processing contents depending on the image area, for example, variable magnification and different processing in the two image areas of the character image and the grayscale image, for example, gradation processing. Most of the processing results of the first category are transmitted to the system control module 600. Based on this, the system control module which has received this issues a control command to other means to proceed with the image forming process.
For example, when the basic image processing means 300 detects that the document is a black and white original, the same means notifies the scanner control means 230, and the first communication control means makes the system control module 600.
To the printer module 400.
To K command and stop CMY development.
Then, the printer control means 430 in the printer module
Effectively energizes only the K developing device 420K to stop development of other colors and efficiently form an image.

The image processing contents of the second category may be automatically activated by the processing result of the first category, may be designated and input from the console 800 by the operator, or may be a combination thereof. A specific color image erasing process will be described as an example of these processes. This process is a process of erasing a specific color contained in the original image, storing and transferring the other colors to form an image on 190A, and is achieved by the color processing unit included in the basic image processing unit 300. It The specific color is input from the console 800 by the operator. In any case, in the copy mode, the RGB image signals input to the circuit 300 are finally recorded as signals C (cyan), M (magenta), and Y for recording.
(Yellow) and K (black) are converted, and this data is passed to the printer module 400. When the original is identified as a black-and-white original or when a black monochromatic processing command is received, monochrome processing is performed and only the K signal is output.

Next, the structure and operation of the extended image processing means 350 will be described. The extended image processing means 350 comprises two circuits shown in FIG. 2, 351 is an image area designation image processing circuit, and 352 is an image editing circuit. The processing means is arranged in the vicinity of the outer periphery of the scanner module 200 so that it can be selectively incorporated according to the user's request. The area designation image processing circuit 351 has a function of performing image processing on the original image identification area designated by the operator, which is different from other general areas. The image editing circuit 352 has various image processing functions, for example, a function of forming a special effect image such as left-right reversal of an image, mosaicization, solarization, posterization, high contrast, and line image formation.

An image trimming process, which is one of the region designation image processes, will be described as an example of the processes included here. Image trimming is a process of duplicating a specific area of an original image and blanking the others. The processing method is JP-A-62.
A well-known technique as disclosed in 159570 is used. However, according to this technology, the felt pen mark attached to the original image is attached to the original, which causes a problem of the original being damaged. In the present embodiment, in view of this drawback, a document image is read by pre-scanning, and this is read by the display means 8 of the console 800.
A trimming range is input and designated by using the cursor movement key 813 and the enter key 814 while displaying the image of the operator pixel on the screen 20 and the area designation image processing circuit 351 blanks the outside of the input area. There is.

Next, the structure and operation of the printer module 400 will be described. FIG. 2 shows the printer module 40.
0 is a schematic configuration, and this module is composed of an image forming unit 400img, a second communication control unit 430 SCSI, a power supply unit 401, and a selective auxiliary device.
The image forming unit 400 img is an electrophotographic photosensitive member 414, a charging unit 419, a laser exposure unit 441, a developing unit 42.
As described above, the name is given to the aggregate of various image forming elements such as 0, the first transfer unit 414, the intermediate transfer member 415, and the second transfer unit 427.

Referring to FIG. 3, 401P is a commercial power plug, 401SW is a power switch, 401 is a power supply means, 430 is a circuit board on which printer control means including a second communication control means is mounted, 430S1 and S2 are printer controls. SCSI connectors on the means 430 having the same shape and the same interface, 430F1 and 430F2 are optical fiber connectors for communication of a selective additional device to be connected to a printer, 411 is a laser diode, 442 is an fθ lens, and 433 is a rotating polyhedral surface. Mirror 444 is a mirror 412A
Is a paper feed tray for automatic paper feed, 412B is a manual paper feed tray, 413A and B are paper feed rollers, 418R is a registration roller pair, 413F, G, H, and J are conveyance roller pairs, 41
4 is a photoconductor drum, 415 is an intermediate transfer belt, 416 is a primary transfer corotron, 417 is a secondary transfer corotron, 4
Reference numeral 19 is a charged scoroton, 420C, M, Y, and K are cyan, magenta, yellow, and black developing devices, respectively.
Reference numeral 0 is a developing device assembly, 421 is a cleaner, 422 is a conveyor belt, 423A is a fixing roll, 423B is a fixing backup roll, 424 is a discharge roll, 425 is a discharge switching roll, and 426 is an image leading edge position detecting means.

Reference numeral 430 in FIG. 2 denotes printer control means.
430 CPU is a microprocessor, 430 RAM is a read / write memory, 430 ROM is a read-only memory, 430 INT is an interrupt controller, 430 PF is a serial communication unit, 430 SYNC is a second synchronization signal generator, 430 XTL is a second crystal oscillator, 430 DMA is DMA. Controller, 430 FIFO is a first-in first-out memory, 430 SCSI is a SCSI controller that functions as a second communication control means, 430S
1, S2 is a connector, 430DV is an input / output circuit for various actuators such as sensors and motors, 430BUS is a bus,
430DC is a data channel. The printer control unit 430 communicates with the system control module 600 or the scanner module 200 according to a predetermined protocol, basically acquires image data in units of main scanning lines, and based on the print mode of the command, controls all units in the module. An image is formed by controlling the emphasis bias, and the final image 190A is output. Also, a sorter 49 selectively added to the printer module.
0 and the like are controlled in an integrated manner.

In the color printing mode, the CMYK colors are formed on a surface-by-surface basis, and the CMYK colors are superposed on the intermediate transfer belt 415 and transferred onto the recording paper 190 to form a final image. Therefore, in the color copy mode, the system control module 600 or the scanner module 2
For 00, the scanning request is output four times for one print. Further, in each RGB single color copy mode, the scanning request for each of MY, YC, and CM is output twice. In forming a color image, it is important to secure the positional accuracy (registration) for each color plate on the intermediate transfer belt 415, and a method of achieving this will be described with reference to FIG.

FIG. 6 shows the synchronization of one image signal. First, the data request command R is sent to the system control means 600 or the scanner module 200.
This shows that the EQ is sent before a fixed time t5 before the image data is received. In color image formation, in the second and subsequent color plate formation, the front end of the color plate image before that is the exposure point 4
It suffices to issue the data request signal REQ before the time t5 which will reach 41X. In the present image forming means for accurately measuring the time at which the head of the previous color plate will reach 441X, the image reference position detecting means 426 is provided facing the intermediate transfer belt 415. Basically, the detection means 42
If the image reference position mark on the transfer belt 6 is detected and the data request signal REQ is issued at the same time as the detection, the image front end of each color plate is formed at the same point on the intermediate transfer belt.

In the so-called constant time before data request method, the other party has a certain mass of the scanning device such as the scanner module 200, and it is necessary for the data source to output a certain amount of preparation time before outputting the image data. Is particularly effective. If the data request command is sent in this way, the data generation side will be the first one after t5 time according to the inter-module protocol as described in the section of the scanner module.
Scan line data is available. As a result, at least phase synchronization is maintained. Next, in order to synchronize the cycle, first, the second synchronization signal generating means 430SYN
The recording data for one scanning line is received from the other party in synchronism with the pulse train period ts2 generated by C, and this is put into the reception buffer 430 FIFO. Further, the rotary polygon mirror 442 is driven in synchronization with the pulse train period ts2, specifically, the phase lock servo drive is performed, and the mirror surface has a period ts.
I changed it to 2. As a result, the bright spot 441X of the laser 441 exposes and scans the photoconductor 414 at ts2 cycles.

Further, as a matter of course, the laser drive circuit 441DV completes the bright spot scanning by the image data D1 to D4.
Based on 752, the laser 441 is controlled to be turned on 4752 times for each pixel. In the copy mode, the scanner module 600 is used as the data transmission side to maintain the above synchronization mechanism. Therefore, no matter how many times the original image is manipulated, the original image data is always obtained after a predetermined time from the command initial transmission, the positional relationship between the paper and the image (registration) is correctly maintained, and the color plate registration is maintained. The color plate registration method has a feature that the image forming interval for each color plate can be set arbitrarily, and in the image formation in the A4 size color copying mode of the embodiment, one is set for each cycle of the transfer belt 415.
In the image formation in the A3 size color copy mode, the color formation is performed, and one color is formed every two cycles of the transfer belt 415 to ensure sufficient time for the color plate exchange such as rotation of the developing device assembly 420.

Further, in the image formation in the color print mode, an arbitrary sheet feeding time can be inserted every time one color is formed regardless of the image size. Thereby, the system control means 630
Even if the amount of birdware such as the memory 630 RAM included in is relatively small, and the 630 CPU has a normal capability, the print processing unit 650PR expands the output image into bitmap data without being limited in time for each color. , The 1
When the color data is completed, the data is transferred from the system control module 600 to the printer module 400, and the printer module 400 forms an image of one color.

Next, the operation of the printer control means 430 as a whole will be described. FIG. 7 is a flow chart showing the operation of the printer control means 430. These functions are shown in FIG.
It is executed by a program of a 30 CPU microprocessor. The execution program is a read-only memory 4
Built in 30 ROM. Reference numeral p401 denotes a power-on operation of the power supply 401, and p402 is a function of initialization processing, for example, setting initial parameters of various circuit elements, starting a watchdog timer, and initial alignment of the four-color developing device assembly 420. In p403, it is determined whether or not the command input from the terminals 402S1 and S2 has not come within the predetermined time. p404 is a function of turning off the heater power of the fixing unit 423, and contributes to reduction of power consumption during standby. p405
Occurs when the watchdog timer leaves normal execution of the program, at which time the failure occurrence notification function p405 notifies the system control module 600 of this. p201
Is an interrupt vector when a failure occurs in the image forming unit 400img and other modules. P411 identifies the failure part and analyzes the cause, and p412 notifies the system control module 600 of this. For example, p413 performs a fail-safe process for avoiding a danger such as a fire when the motor 414M is overheated. p420 is an interrupt vector when information is input to the terminals 402S1 and S2. At this time, the sleep timer is stopped in p421. p422 checks the received content and branches it to one of the following five types.

First, TEST of p430 (TEST
(Unit Ready) is a route for inquiring whether the printer module is capable of forming an image, p4
At 31, the printer module status including the selective addition devices 480 and 490 is returned. p490 is a route when a self-diagnosis DIAG (DIAGnostic) is requested from the printer, and typically a failure occurrence notification function p40
5, p412 is requested after notifying the failure, p491
Through p493, self-diagnosis and its response processing are performed.

P440 is an inquiry about various setting modes of the printer module SENS (MODE SENSe)
Then, in the processing from p441 to p445, the selective addition device 48
The mode setting status of the printer module including 0 and 490 is returned. p450 is various setting mode setting SEL
It is the path at the time of requesting (MODE SELECT).
Pair with NS. Various parameters are p451 to p45
Set in each routine of 6. In p456, in the case of the copy mode, the print image data request destination is the scanner module 2
00, in the case of the print mode, the system control module 600 is registered in advance.

Reference numeral p460 is a pass at the time of a PRINT request, and normally in a single-color image forming process, once for one print,
4 times for full color processing and 2 for secondary color mono color processing
There are consecutive requests. As described above, even if a plurality of PRINT requests for one print arrive at irregular intervals, it is possible to control to correctly overlap each color plate. When this request is made, first the motor 414M is started by p461, and then p4
The image forming sequence control is started at 62, and the detection operation of the reference position sensor 426 is monitored at p426. Immediately after the sensor detects the image reference position mark on the transfer belt, p467 is activated and the data transfer request signal REQ is output to the scanner module 200 or the system control module 600. In p465, the line counter (scan line counter) provided in the memory 430RAM is reset. This counter is the second synchronization signal generating means 430 SYN.
C is set to 1 by the synchronization pulse generated once for one scan line
Is incremented by one.

In p466, the time from when the data transfer request signal REQ is issued until the data transfer destination prepares the data of the first line, in other words, when an image of another color already exists, it is exposed. It is a task of monitoring the time corresponding to the return to the corresponding position 441X. When this time elapses, p467 resets the line counter for the second time, further opens the output gate of 430 FIFO which is a buffer memory for image data, and prepares to deliver the recorded image signal to the laser driver 441D through the image signal line 430D. To do.

Thereafter, p468 to p472 are terminals 402.
A task group for storing the recording image data fetched from S1 and S2 in the 430 FIFO for each scanning line.
Then, the second synchronizing signal generating means 430SYNC detects the synchronizing pulse generated every scanning line. p469 is terminal 40
The recorded image data for 4752 pixels of one scanning line acquired from 2S1 and S2 is stored in the 430 FIFO. At this time p
At 470, the line counter is incremented. p4
In 72, this loop is equivalent to the recording size, for example, in A3 size paper, there are 6720 scanning lines, that is, 6720 times. When laser scanning for one surface is completed, p473
Closes the exit gate of the 430 FIFO and cuts off the laser driver drive signal. At this time, of course, the terminal 402S1,
The recording image data is received from S2 and completed. p473
Checks whether the current image formation was the last color image formation of the last recorded color image, and if it is not the last color image, the remaining image forming sequence control is completed, and the motor is stopped at p480. If the final color image formation has been completed, the paper feeding described in p474 to p478, 2
The next transfer, fixing, and paper discharge processes are executed, and the recorded image 190
B is discharged out of the printer module.

Next, the operation of the image forming section 400img will be described. A data request signal REQ is sent to the scanner module 200 in the copy mode, and to the system control module 600 in the print mode or the facsimile mode, "send recorded image data after a predetermined time". The printer module is the printer control means 4
For each of the C, M, Y, and K colors input to 30, the pixel density is 1/16 mm or 1/24 mm for both main scanning and sub-scanning.
Based on the bit recording data, the recording dot density is 1/16 m for both CMYK colors in both main scanning and sub scanning on the transfer paper.
A full-color visible image having a dot pattern of m or 1/24 mm is formed and output. Recording dot density 1 /
The selection of 16 mm or 1/24 mm dots is designated in advance by a mode selection command. Default is dot density 1
/ 16 mm. When the image forming cycle is started, first, the photosensitive drum 414 is rotated counterclockwise and the intermediate transfer belt 415 is rotated clockwise by the drive motor 414M. With the rotation of the intermediate transfer belt 415, K toner image formation, C image formation, M image formation, and Y image formation are performed, and finally a toner image is formed on the intermediate transfer belt 415 in the order of KCMY. The image recording signal for image formation is supplied from the scanner module 20 in the general transfer mode, and from the system control module 600 in the special copy mode including intelligent image processing, the facsimile mode or the print mode.

First, in the operation in the copy mode, various copy conditions are designated by the operation unit connected to the system control module 600 (magnification, density, number of copies, etc.), and when the copy start key is pressed, the system control module is pressed. Reference numeral 600 sends a copy mode start signal to the scanner module 200 and the printer module. Scanner module 20
0 and the printer module start the copy preparation operation in response to the copy start signal. Here, it is assumed that a color original / black and white original identification copy mode (hereinafter referred to as ACS mode) is designated. When the image forming cycle is started, the printer module first drives the polygon motor for laser scanning, and when the motor rotational speed stabilizes at the specified rotational speed, a polygon ready signal is generated and laser scanning is started. The photoconductor drum 414 is rotated counterclockwise and the intermediate transfer belt 415 is rotated clockwise by the photoconductor drive motor 414M. The photoconductor discharge lamp is turned on, the residual charge of the photoconductor is erased and the photoconductor potential is set to 50V.
Below. Next, the charging scorotron 419 uniformly charges the photoconductor drum 414 with negative charge to −700 V by corona discharge. Before the start of image writing, the laser output is set to white level data, and the photoconductor potential drops to the non-developing potential. When the transfer belt rotates and the image reference position detection unit 426 detects the image reference position mark on the transfer belt, the printer sends a scan start signal to the scanner.

The scanner starts sending image data to the printer after time t5, and the received image data is converted into laser output data by the writing control circuit and exposed on the photosensitive member to form an electrostatic latent image. Photoconductor drive motor 414M
At the same time, the developing motor is driven, the developing sleeve of the K developing device facing the photoconductor rotates, and the developing bias of AC + DC is applied to the developing sleeve by the high-voltage power source to visualize the electrostatic latent image by reversal development. Convert to toner increase. The toner image is transferred onto the transfer belt by the primary transfer corotron. When the writing of the image data is completed, the system control module is notified of the completion of the writing and waits for the subsequent determination of the copy mode control.

The system control module receives the detection result of the color document automatic detection circuit 320 from the scanner. If the detection result is color, it instructs the printer to start the next cyan image formation, and if the detection result is black and white. The printer is instructed to complete the image formation and shift to the paper transfer process. In the case of color, the printer exposes and develops the density pattern for image density sensor detection used for developer density control after K image exposure, drives the revolver motor, rotates the developing unit 90 degrees counterclockwise, and The developing device is moved to the position facing the photoconductor.

When the next image reference position mark is detected, a scan start signal for a cyan image is sent to the scanner. As described above, 5 hours after the scan start signal is sent, the cyan image transferred to the transfer belt by the primary transfer corotron is controlled to be the same as the K image on the transfer belt by controlling the image data to be sent from the scanner. It will be transferred and superimposed on the position. Hereinafter, an image forming operation similar to K image formation is performed for cyan, and the system control module is notified of the end of cyan image exposure. The system control module commands the printer to start the image formation of the third color (magenta). After the completion of the third color, the system control module drives the paper conveyance system by the main motor together with the image formation start command for the fourth color (yellow), and drives the paper feed clutch of the paper feed tray designated by the system control module to load the paper. Send from the tray.
The paper passes through the intermediate roller driven via the intermediate clutch, further passes through the registration sensor to reach the registration roller, and is applied to the stationary registration roller,
The leading edge of the paper stops. After a predetermined time counted by a counter that starts when the leading edge of the registration sensor image paper is detected, the intermediate clutch is stopped to form an appropriate slack for the paper and stop the paper. The registration clutch is driven and the paper is sent to the secondary (paper) transfer unit at a timing controlled so that the front end of the paper and the front end of the visible toner image on the transfer belt in which the four colors are superimposed coincide with each other. .

The recording signal is the printer control means 430SCS.
The laser drive circuit 441DV which is input from the I terminal 430S1 or 430S2 and is a recording control circuit controls the light emission of the laser diode 441 in input pixel units based on the recording signal. The recording signal is 4 bits per pixel. More specifically, the maximum C density pixel emits laser light corresponding to the entire main scanning width, the white pixel does not emit light at all, and the intermediate density signal emits light for a time proportional to the density data. Is done. When the raster image is exposed in this way, the photosensitive drum 414 initially charged uniformly.
In the exposed part of, the charge proportional to the amount of exposure light disappears,
An electrostatic latent image is formed. The toner in the developing device 420C is negatively charged by stirring with the ferrite carrier, and the cyan developing roller 420C of the developing device is negatively charged with a negative DC potential by a power source means (not shown) with respect to the metal base layer of the photosensitive drum 414. And are biased to the superimposed potential.

As a result, the toner does not adhere to the portion of the photoconductor 414 where the electric charge remains, and the C toner is adsorbed to the portion having no electric charge, that is, the exposed portion, and the C toner similar to the latent image is obtained.
A visible image will be formed. In addition to the light emission control based on the recording signal of the laser diode 441, the laser drive circuit 441DV also generates special image pattern data at the time of Y image formation, and unconditionally adds this to the input image data. That is, it has a function of driving the laser diode 441 with the logical sum of the input image data and the special image pattern data.
This pattern is a fine image in which the system identification number is patterned, and is attached to assist this tracking when an illegal image such as securities is formed by some method.

In this way, when the toner image on the photoconductor rotates counterclockwise and reaches the position opposite to the primary transfer corotron 416, it comes into contact with the photoconductor and coronas on the intermediate transfer belt 415 driven at a synchronous speed. Transcribed. Photoconductor 414
The small amount of untransferred residual toner above is cleaned by the cleaning device 421 in preparation for reuse of the photoconductor 414. The toner collected here is stored in a waste toner tank (not shown) via a collection pipe. The intermediate transfer belt 415 is made of a material having a relatively large specific resistance value in order to favorably maintain a long-term image carrying characteristic which is particularly required in the print mode. As a result, the toner image can be carried without disturbing the toner image even if the time until the next M toner image is formed is long, for example, 20 minutes.

Next, prior to performing the M image forming raster exposure based on the M signal, the developing device assembly 420 is rotated counterclockwise so that the M developing roll 420M faces the photoconductor 414. Next, the leading end position of the previously formed C visible image is detected by the leading edge detecting means 426, and the request signal REQ to the scanner module 200 or the system control module 600 "Send recording M image data after a predetermined time".
Emit again. This request signal is sent to the image position detecting means 426.
Is issued at the time when it is detected as a registration C toner mark image which is slightly added before the effective C image in the previous step. Also, instead of the C toner mark image, a permanent mark may be previously attached to the intermediate transfer belt in advance. If the M signal is sent exactly in synchronization with this request signal, M image exposure and development 1
The next transfer is performed, and accurate color plate alignment is performed on the original existing C image, that is, the M image is correctly superimposed on the C image on the intermediate transfer belt 415. When the M raster image is exposed in this manner, the charge which is initially uniformly charged on the exposed portion of the photoconductor drum 414 loses the charge proportional to the amount of exposure light, and an electrostatic latent image is formed.

The M toner in the developing device 420M is negatively charged, and the developer on the developing roller 420M of the developing device contacts the photosensitive drum 414 and is biased to the same potential as in the C developing. Therefore, the toner does not adhere to the portion of the photoconductor 414 where the electric charge remains, and the M toner is adsorbed to the portion exposed by the M signal, which is the same as the electrostatic latent image.
A visible image will be formed. Similarly, Y image is C
The K image is formed on the M toner image and the K image is formed on the CMY image in an overlapping manner. In the copy mode, since the basic image processing circuit 300 performs UCR (undercolor removal) processing,
There is little chance that one pixel will be developed with all four color toners. The full-color image formed on the intermediate transfer belt 415 thus rotated at least four times is rotatably transferred to the secondary transfer 417 portion.

On the other hand, when the image formation is started, the transfer paper 1
Reference numeral 90 designates three feeding units, that is, the cassette 412A, the manual feeding tray 412B, or the external feeding port 412C from any of the feeding rolls 413A and 413B or the conveyance roll pair 41.
The sheet is fed by the feeding or conveying action of 3F and stands by at the nip of the pair of register rolls 418R. Then, when the front end of the toner image on the intermediate transfer belt 421 reaches the secondary transfer corotron 427, the register roll pair 418 is set so that the front end of the transfer paper 190 exactly coincides with the front end of the image.
R is driven, and the registration of the paper and the image is performed.

In this way, the transfer paper is superposed on the intermediate transfer belt image and passes under the secondary transfer corotron 417 connected to the positive potential power source. At this time, the transfer paper is positively charged by the corona discharge current, and most of the toner image is transferred onto the transfer paper. Then, when passing through a neutralization core (not shown) connected to a grounding source arranged on the slightly left side of the secondary transfer corotron 417, the transfer paper discharges electric charges, and the attraction force between the intermediate transfer belt and the transfer paper almost disappears. .. Eventually, the weight of the transfer paper exceeds the suction force, and the transfer paper 190 is separated from the intermediate transfer belt and transferred to the transport belt 422.

The transfer belt on which the toner image is placed is the conveyor belt 42.
2 to the fixing device 423. At this time, heat and pressure are applied in the nip portion between the overheated fixing roll 423A and backup roll 423B, the toner is melted and transferred, and the toner is absorbed into the fibers of 190 to fix the image, and the copy image is completed. The completed copy is then sent out of the main body by the discharge roll pair 424. The ejected copy papers are stacked face up on a tray (not shown), and during double-sided copying, the switching roll 425 is moved to the right along with the paper deflection, and is pressed against the opposite conveyance rolls to reversely scan the transfer papers and then conveyed. The pair of rolls 412H guides the sheet to the automatic paper feed cassette 412A for double-sided copying. At this time, the copied transfer sheets 190A are stacked with the copy side facing up.

Next, the structure of the system control module 600 will be described. The configuration of system control module 600 is shown in FIGS. The system control module includes system control means 630, console means 800 including key input means 810 and bitmap display means 820, floppy disk device 740, magneto-optical storage device or C.
D-ROM drive device 730, IC card drive device 7
45, third communication control means 630 SCSI, and acceleration processing device 750. All of these means are housed in the system control module housing 600 of FIG. Further, the printer module 4 is connected by the coupling means 600AL1.
It is configured to fit into the coupling means 400AL2 on the upper part of 00 to enable fastening.

In FIG. 3, reference numeral 600 is a vertical cross-sectional view of the system control module, and the console 800 is arranged on the front side so that the scanning surface is exposed and can be operated even when the scanner module 200 is stacked. Further, the floppy disk device 740, the magneto-optical storage device or the CD-ROM drive device 730, and the IC card drive device 745 have the recording medium insertion surface on the front side in consideration of usability, and the third communication control means 630 SCSI 2 is on the rear surface. The configuration of the system control means 630 is shown in FIG. In the figure, 630 CPU is a microprocessor, 630 RAM is a read / write memory, 630 ROM is a read-only memory, and 630 IN.
T is an interrupt controller, 630 SYNC is a synchronizing signal generator, 630 XTL is a crystal oscillator, and 630 DMA is a DMA.
A controller, 630 FIFO is a first-in first-out memory, 630 SCSI is a SCSI controller that functions as a third communication control means, 630 S1 and S2 are SCSI terminals, 630 BUS is a bus, 650 DC is a data channel, and 650 is a physical magnetic disk. Although it is a drive, it is also called an application processing unit because it functionally stores a system control program. Further, there is no problem in substituting, for example, a ROM as the storage medium. First of system control means 630
Function is system control of various module configurations as shown in FIG. The second is control of the console 800 such as screen display and key input, and the third is a function of controlling communication with a facsimile or an external host computer and a function of expanding recorded image data.

Referring to FIG. 2, the application processing unit 650 includes a copy processing unit 650CP and a facsimile processing unit 650F.
X, print processing means 650PR, intelligent image processing means 650
It is composed of AI. All of these processing means share the hardware resources of the system control means 630 and share the HDD.
It is realized by executing the program stored in. The copy processing means 650CP is the scanner module 20.
In the system in which 0 or the printer module 400 and the system control module 600 are connected, this is a process for integrally controlling the entire system and realizing an image copying function. The facsimile processing means 650FX is a processing means for realizing a facsimile function in a system in which the scanner module 200, the printer module 400, the system control module 600, and the public line 650FC are connected. The print processing unit 650PR includes the printer module 400 and the system control module 60.
This is a process for realizing a print function for performing permanent visible image formation output in a system in which 0 is connected and print data is received from the external computer 650PC.

The intelligent image processing means 650AI is a process for realizing an intelligent image processing function in the system in which the scanner module 200 or the printer module 400 and the system control module 600 are connected. Here, the intelligent image processing is, for example, the scanner module 200.
The original image 180 and the output image 190 are recognized by recognizing characters from the image read by the user and creating a graph based on the characters.
The purpose is to perform image processing that is significantly different from.
In the intelligent image processing, unlike the general copy mode, the image data is once taken into the system control means, is subjected to the action of the intelligent image processing 650CP, and is then delivered to the processed image data printer module 400 to form an image. .

FIG. 8 is a diagram for explaining the operation of the copy processing means 650CP and the print processing means 650PR, FIG. 9 (a) is a copy operation timing chart, FIG. 9 (b) is a print processing operation timing chart, and FIG. 9 (c). FIG. 7 is a timing chart when a failure occurs during the copy processing operation. In FIG. 8, a thin line frame represents a process common to the copy process 650CP and the print process 650PR, a thin broken line frame represents a process unique to the copy process 650CP, and a thick line frame represents a process unique to the print process 650PR.

P601 is a start address when the printer module 400 is powered on. The power of the printer module 400 is turned on because the system control module 600 is assembled together with the printer module 400 so that power is supplied from the printer module. In p604, parameters on various software, for example, internal registers of the interrupt controller 630INT are initialized. The step p602 indicates that the watchdog timer has timed out, and the data to be backed up is protected, that is, data is saved to 650 NON, and the process branches to the initialization process. p605 monitors the presence or absence of various events, and p606 examines their contents 4
Jump to the seed path.

The processing of p610 branches when a notification of the occurrence of a failure is received from the scanner module 200 or the printer module 600, and the contents are confirmed from p611 to p614. In p615, the operator displays the details of the failure on the screen 820, and in p612, the information is notified to the service center connected to the public line. At p617, an instruction such as a failure recovery procedure is received from the service center, which is displayed at p618. The p620 branches when a notification of an abnormality occurrence is received from the scanner module 200 or the printer module 600. Abnormality here refers to a state where the supply of toner, recording paper, etc. is insufficient, the housing door is opened, etc., and the supply can be replenished and the door can be easily closed.
The contents are confirmed from 621 to p624. p615 displays a message on the screen 820 so that the details of the abnormality can be seen, and p625 displays a message on the console screen 820 regarding a procedure for returning to the normal state such as urging supply of supply.

In p660, the operator uses the console 800
Various copy modes input from, for example, when mode setting such as image processing mode designation, sort mode designation, or when a mode setting command is received from the host computer in the print mode, a response screen is displayed on the display unit 820 at p661. , Sends a mode selection command to the scanner and printer module. p630 branches when the start button 811 is pressed or when a start command is received from the host computer in the print mode, and from p631 to p632 the printer module 4
00 to inquire about the preparation status. Furthermore, in copy mode, p
The scanner module 200 is inquired about the preparation status from 633 to p634. If these are ready, only in the copy mode, a COPY command is sent to the scanner module 200 at p635 and a PRINT command is sent to the printer module 400 at p636.

In the copy mode, commands are exchanged between the scanner module and the printer module.
According to the procedure described in the section of the module, image data is transferred and a copy is generated. Only in print mode
In p636, the system control module 60 obtains image data for one page of one color according to the procedure described in the section of the printer module.
0 to the printer module 400. p637
From p to 640, an inquiry is made as to whether or not a series of image reading process and image forming process have been completed, and if it has returned to the initial state, this is displayed on the screen 8202. p64
In step 2, it is checked whether or not a predetermined color plate and a predetermined number of copies have been completed, and if the remaining image formation is still required, the process returns to the beginning. During color copying, this loop will be repeated four times.

FIG. 9 shows the signal flow and timing of the three modules. (A) is the operation timing of the copy mode, (b) is the operation timing of the print mode,
(C) shows the operation timing when a failure such as a transfer paper jam occurs. In the same figure (a), the system control module 600 uses the copy control means 650CP to print four colors for four times.
Issue T commands at equal intervals. In the same figure (b), the system control module 600, by the action of the print control means 650PR, issues PRINT commands four times for four colors randomly, not at equal intervals. When there is a large amount of print data, the issuing interval is generally much longer than the copying mode interval. Again 65
As a result of the unevenness of the data size for each color handled by 0PR and the nonuniformity of the software expansion work of the bitmap data, the variations in the completion time appear, and the PRINT commands are issued at irregular intervals according to this variation. In the print mode, since the scanner module 200 is not involved at all, even if it is physically separated, it operates without any trouble. In FIG. 7C, the printer module 4 is set in the copy mode.
An example of processing timing when a transfer paper jam occurs at 00 is shown.

Next, the operation of the image forming apparatus according to the present invention will be described. FIG. 10 shows a timing chart.
The system control module first receives the color mode from the host computer, then waits for a print command, receives the print command, receives the image data of the first color (BK image in the full color mode), and develops the image on the bitmap memory. Start the time measurement counter at the start. This counter is, for example, 1se after activation.
It is a counter that counts up every c and measures time.

After the completion of the development, the received color mode and the image development time measured by the time measurement value timer are sent to the printer module, and then the system module issues a print command to the printer control module. Subsequent BK image forming operations are similar to those of the conventional art.

After receiving the print command, the printer module activates the polygon motor, and after a few seconds, the polygon motor stabilizes its rotation and becomes ready. At this point, the main motor, the photoconductor motor, and the developing motor are turned on, the transfer belt starts to rotate by the activation of the photoconductor motor, and after the lapse of t5 time from the detection of the mark on the transfer belt mark, the BK image data is transferred to the system control module. Read from. The read data is sent to the laser driver via FIFO, and after the image data for the transfer size is read, the transfer belt mark is a predetermined distance LBOFF from the mark detection sensor position.
After moving before, turn off the polygon motor, motors, charging, developing bias, etc., and after the next transfer belt starts to rotate,
Belt mark detection can be generated after (LBOFF / circulation speed) time. Even when the power is turned on, the transfer belt mark is moved by a predetermined distance LB from the position of the mark detection sensor due to the circumferential movement of the transfer belt. In this way, by stopping the peripheral motion of the polygon motor and other motors, noise reduction and labor saving can be achieved. A timing chart of the conventional technique is shown in FIG.

As an example, there is a method of determining the value of LBOFF so that the time when the REQ command can be generated after receiving the print command <LBOFF / circulating speed. Another method is to set the motor start-up time <LBOFF. When LBOFF is set short as described above, the print command is received before the polygon motor becomes ready, and the transfer belt is rotated once to overlap the four colors.
You must wait until the next belt mark detection. Also, stop the transfer belt at a position where the image on the transfer belt does not contact the photoconductor, and
There is also a method of preventing image deterioration such as rubbing due to speed fluctuation of the transfer belt. The calculation method of LBOFF in this case will be described with reference to FIG.

Assuming that FIG. 6 is a diagram showing the moment of marker detection, the image front end is formed at the 441X position after t5, and the marker has a peripheral velocity of V, and the marker is at V × t5 minutes from the marker detection sensor position. Are moving. afterwards,
It may be stopped after the toner image on the photoconductor is completely transferred onto the transfer belt, so that one color image forming time × V + L1
Only the transfer belt mark is moving. Therefore, L
BOFF <(Belt circumference- (Image formation time for one color x V +
11) −V × t5). Further, for forming an image of the next color, the revolver is rotated by 90 degrees and rotated to the C color developing position. After the transmission of the BK image is completed, the system module develops the C image which is the next color.

On the other hand, in the printer module, all B
After receiving the K image data, (the first notified image development time tMEM-polygon motor stabilization time tRDY = tR
Start timer 1 with ISE1) set.
When tRISE1 is a negative value, that is, when tRDY is longer, 0 is set in tRISE1. Then, after this timer 1 finishes counting for tRISE1, the polygon motor is turned on in advance for C image formation. Also, the motors are started at the time of polygon ready. In the system module, the print command is issued after the C image development is completed. At this point, the polygon motor has already been started and the rotation is stable, so that the C image can be immediately formed. is there. Therefore, the printer module does not need to skip the transfer belt mark after receiving the print command until the polygon ready state is reached. When the transfer belt mark is detected, the reading of the C image data is started after t5 hours, and thereafter, M, Y The image formation is performed in the same manner.

It is also possible to display the time until the end of printing on the console display section, and the writing time for one line is set to t1LINE, and the printing size in the sub-scanning direction is set to LSI.
Assuming ZE and writing at 400 dpi, the time tTRANS required to form one image is (LSIZE * 400)
/(2.54*t1LINE). On the other hand, in the case of full-color printing, it is necessary to develop the image three times after measuring the image development time. In addition, after the REQ command is issued from the printer, t5 time when the image data is sent from the system module is four times, A time such as the first color polygon motor rising time tRDY is required.

Therefore, the value displayed on the console at the end of the first image development is 3 * tMEM + 4 * tTRAN.
S + 4 * t5 + tRDY, and thereafter, the display value may be counted every 1 sec. However, in this case, an error occurs in the time required for command communication. As another method for calculating the time until the end of printing, the time required for printing other than the image development time is determined beforehand by the machine conveyance length, transfer belt length, photoconductor length, laser irradiation position, peripheral speed, print size, etc. Since it can be calculated, for example, in the case of an image forming apparatus designed such that the printing speed of the first sheet of A4 horizontal size is 30 seconds when the image development time is 0, it is 30 + 3 tMEM. The time unit for displaying the time required for printing on the console is, for example, 1 sec.
It is also effective to count down the display value in units of 1 minute so that the user does not feel the difference between the calculated and displayed value and the actual required time due to motor speed fluctuations, communication time fluctuations, and the like.

Next, the temperature control of the fixing means will be described. In FIG. 12, the vertical axis is the fixing roller temperature, and the horizontal axis is the heater ON.
It is the time from. In this embodiment, the target value of the fixing temperature at which the toner and the transfer paper are melted and fixed is set to Temp.
When it is set to H and in a state where fixing is not particularly required such as during image development for power saving, control is performed to reduce TempL to the target temperature. As is clear from FIG. 12, Temp
It takes tFH-tFL time to raise the temperature from L to TempH. Therefore, the fixing heater is turned on for tFH-tFL time before the transfer sheet enters the fixing unit.
If N is set, it means that the fixing temperature has reached the fixing target temperature TempH when the transfer sheet enters the fixing unit.

This timing chart is shown in FIG.
The image forming operation is performed as described above until the time of forming the BK, C, and M images. On the other hand, due to the mechanical configuration of the machine, the image front end is transferred to the transfer paper from the time when the image front end is formed.
Since the time until the paper is fed into the fixing unit is tFUS which is predetermined, after the reception of all the M image data, the timer 2 displays (tMEM-((tFH-tFL)-
If tFUS) = tRISE2) is set and set as a star, if the target fixing temperature is set to TempH at the end of the timer 2 time-up, the fixing heater is turned on continuously, and when the transfer paper enters the fixing unit, it is fixed. The temperature can reach the fixing target temperature TempH.

Note that (tFH-tFL) -tFUS is tB.
If it is F, when tBF> tMEM, the timer 2 is started at the end of the C image formation, not at the end of the M image formation, and the set value of the timer 2 is 2tMEM.
-TBF-Sets the one-color image formation time.
In this equation, the time from the print command to the REQ command and t5 time are not taken into consideration, but if these are included, the continuous ON of the fixing heater will be delayed, so there is a margin time for the fixing temperature to reach the target value TempH. If you think about it, you don't have to include it. However, if the power saving is further promoted, it is possible to use the included formula.

Next, a flow for realizing the operation of the image forming apparatus according to the present invention as described above and the operation for power saving will be described. The flowchart of the program of the system control module is as shown in FIG. In s1, it waits for the reception of the color mode from the host computer, and after receiving it, it proceeds to s2 and waits for the reception of the print command from the host computer. After receiving the print command, the development time measuring counter is started in s3 and waits for image data in s4. After receiving the data, the image data is set in the bitmap memory in s5, and this is called image development. Then s
In step 6, it is checked whether the image reception is completed. If it is not completed, the process returns to s4. If it is finished, it is checked in s7 whether the first image development is finished. If it is the first time, the color mode is issued to the printer in s8, the development time measurement counter is stopped in s9, and the measured value is measured. Is issued to the printer.

At this point, the time required to complete printing may be displayed on the console and the countdown of printing time may be started. If it is not the first time, jump to s10, s
At 10, waiting for the REQ command, which is an image data request from the printer, and after receiving the REQ command, the process proceeds to s11,
The image data is transmitted, and it is checked in step S12 whether the image data has ended. If it has not ended, the process returns to s10, and if it has ended, it is checked in s13 whether or not the transfer for the color mode has ended. 4 in full color mode
The image transfer is performed twice, for example, in the R, G, and B modes, the image transfer is performed twice. If the image transfer is not completed here, the process returns to s2, while if it is completed, the process returns to s1.
Wait for the next print instruction from the host computer.

The flowchart of the printer module program is as shown in FIG. In s1, the reception of the color mode is waited, and in s2, the development time is waited. In s3, the print command is waited, and in s4, it is checked whether the polygon is OFF or not. If it is not OFF, the process jumps to s6. If it is OFF, the polygon is turned ON in s5 and the polygon ready is waited in s6. When the polygon becomes ready, the motors, charging and developing bias are turned on in s7, and then s
Proceed to 8 and wait for the detection of the belt mark. When the belt mark is detected, it waits for t5 time to elapse at s9, and after t5 time elapses, image reading is started at s10. Specifically, the REQ command is issued to the system module, and in s11, the completion of reading the image data is checked.

After the completion of the check, it is checked in s12 whether or not the final image is over. If not, the timer 1 is set to TRISE1 in s13, and the timer 1 is started in s14. At s15, it is checked whether the next image formation is the final image formation.
After setting TRISE2 to the timer 2 at 16, the timer 2 is started at s17, and if not the final image formation, the process returns to s3. If the final image has been checked in s12, after printing on paper in s18, the process returns to s1 and waits for the next printing. On the other hand, a timer interrupt is generated in the microprocessor of the printer module, for example, at intervals of 1 sec. In this case, the values set in the timers 1 and 2 are values in units of 1 sec.

The flowchart of the interrupt program is shown in FIG.
As shown in. First, in s1, it is checked whether or not the timer 1 is starting. If it is not starting, the process jumps to s6. If the timer 1 is starting, the contents of the timer 1 are subtracted in s2, and it is checked in s3 whether the timer 1 has become 0. If not 0, s6
If it is 0, the polygon is turned on at s4 and the timer 1 is stopped at s5. Next s6
Then, check whether timer 2 is starting,
If it is not starting, the interrupt program is terminated and the operation returns to the point where the interrupt occurred. If timer 2 is starting, the contents of timer 2 are subtracted in s7, and
At 8, it is checked whether the timer 2 is 0 or not. If timer 2 is not 0, it returns, while if it is 0, s
At 9, the target fixing temperature is set to TemppH, and at s10, the timer 2 is stopped.

[0095]

The present invention is configured as described above, and in the first means, the image data receiving means is a plurality of image data which are sequentially input at non-equal time intervals from the external control means via the communication means. Accept one by one. The printer control means forms an electrostatic latent image on the photoconductor on the basis of the image data received by the image data receiving means, and each image data is designated by the external control means via the communication means. The electrostatic latent image is developed using a color developing device to form a toner image on the photoconductor. This toner image is transferred to the toner image carrier by the first transfer means once, in preparation for receiving the next image data. When the second image data is received by the image data receiving means, the printer control means uses the developing device of the color designated by the second image data as in the case of the first image to form toner on the photoconductor. Create an image. This toner image is transferred to the toner image carrier by the first transfer means, and a superposed image of two image data is formed on the toner image carrier. This image forming process is repeated the number of times instructed by the external control means, and the superposed toner images of a plurality of desired image data formed on the toner image carrier are collectively transferred to the recording medium by the second transfer means and fixed. The toner is fixed on the recording medium by the means. Here, in the process of forming a superposed image on the toner image bearing member, the circumferential movement of the toner image bearing member is stopped from the completion of the transfer to the toner image bearing member until the start of image formation based on the next image data. Therefore, it is possible to provide an inexpensive image forming apparatus without having an enormous bitmap memory for each color, and among the images formed by being superimposed on the toner image carrier, other than the final image. Since the image does not come into contact with the photoconductor excessively due to the movement of the toner carrier, the toner image is not disturbed by the reverse transfer of the toner image to the photoconductor, the discharge phenomenon, etc. It is possible to obtain an image of the same quality as when a superimposed image is formed. Further, since the circumferential movement of the toner image carrier is stopped during the reception of the image data, unnecessary noise is not generated, and deterioration of the components due to wear or the like can be prevented, so that the life of the apparatus can be extended, and It also contributes to the reduction of power consumption.

In the second means according to the present invention, the printer control means is based on the next image data after the completion of the transfer to the toner image carrier in the step of forming the superimposed image on the toner image carrier. Since the driving of the polygon motor is stopped until the start of image formation, in addition to the effect of the first invention, it is possible to further reduce noise, extend the life of the apparatus, and reduce power consumption. In the third means according to the present invention, the time from the start of transfer of the first image data to the start of image formation is detected, and the printer control means is based on the detected time until the start of image formation by the second and subsequent image data. Since the rotation of the polygon motor is controlled to rise to normal rotation, the latent image forming process can be promptly entered when necessary even if the polygon motor is controlled to be stopped in the second invention. It is possible to provide an image forming apparatus that does not impair the effects of the invention of item 2 and does not extend the image forming time.

In the fourth means according to the present invention, the printer control section obtains the number of times of image data transfer from the external control means via the communication means before the transfer of the first image data is started,
The time from the start of the transfer of the first image data to the start of image formation is detected, the end time of the entire image formation process is estimated from the detected time and the number of times of image data transfer, and the end time is displayed. It is possible to provide an image forming apparatus having a good human interface without getting irritated without knowing the time. In the fifth means according to the present invention, the printer control section obtains the number of times of image data transfer from the external control means via the communication means before starting the transfer of the first image data, and then the temperature of the fixing means is set during the fixing operation. The temperature is controlled to a lower temperature, and the temperature of the fixing unit is controlled to return to the temperature at the time of the predetermined fixing operation until the recording medium reaches the fixing unit after at least the second transfer is completed. Power consumption can be reduced without extension.

In the sixth means according to the present invention, the printer control means obtains the number of times of image data transfer by the external control means via the communication means before starting the transfer of the first image data, and then the temperature of the fixing means is changed. The temperature is controlled to be lower than that during the fixing operation, the time from the start of the transfer of the first image data to the start of image formation is detected, and the fixing operation time is predicted based on the detected time and the number of times of image data transfer. The temperature of the fixing unit is controlled so as to return to the temperature during a predetermined fixing operation before the recording medium arrives at the fixing unit so that the image forming time can be extended with a simple configuration so that the recording medium can be promptly executed when necessary. It is possible to efficiently reduce the power consumption when the fixing operation is unnecessary.

[Brief description of drawings]

1A to 1E are views showing various system configurations by assembling modules.

FIG. 2 is a diagram illustrating functional blocks of an image forming system and signal flows.

FIG. 3 is a diagram showing a mechanical portion of the image forming system in FIG.

FIG. 4 is a timing diagram of the scanner module 200.

FIG. 5 is a control flowchart of the scanner module 200.

FIG. 6 is a timing diagram of the printer module 400.

7 is a control flowchart of the printer module 400. FIG.

8 is a control flowchart of the system control module 600. FIG.

9A to 9C are timing charts of the image forming system.

FIG. 10 is a diagram showing an operation timing chart of the image forming apparatus of the present invention.

FIG. 11 is a diagram showing an operation timing chart of the conventional image forming apparatus.

FIG. 12 is a diagram illustrating temperature control of a fixing unit in the image forming apparatus of the present invention.

FIG. 13 is a diagram showing a temperature control flowchart of the fixing unit in the image forming apparatus of the present invention.

FIG. 14 is a diagram showing a flowchart of a program of a system control module in the image forming apparatus of the present invention.

FIG. 15 is a diagram showing a flowchart of a program of a printer module in the image forming apparatus of the present invention.

FIG. 16 is a diagram showing a flowchart of an interrupt program in the image forming apparatus of the present invention.

[Explanation of symbols]

180 ... manuscript, 190 ... recording paper, 200 ...
Scanner module, 200rd ... Image reading unit, 207 ... Imaging device, 201 ... First power supply means, 230 ... Scanner control means, 230SC
SI ... First communication control means, 230 SYNC ... First synchronization signal generating means, 211 ... Carriage home sensor, 300 ... Basic image processing means, 400 ... Printer module, 400 img ... Image Forming part, 40
DESCRIPTION OF SYMBOLS 1 ... 2nd electric power supply means, 414 ... Photosensitive drum, 415 ... Intermediate transfer belt, 426 ... Image front end detection means, 430 ... Printer control means, 430S
CSI ... Second communication control means, 430SYNC ...
Second synchronization signal generating means, 600 ... System control module, 630 ... System control means, 650 ...
Application processing unit, 800 ... Console.

Continuation of front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical indication location G03G 21/14 (72) Inventor Yoshiki Yoshida 1-3-6 Nakamagome, Ota-ku, Tokyo Within Ricoh Co., Ltd. ( 72) Inventor Kuniyuki Sato 1-3-6 Nakamagome, Ota-ku, Tokyo Within Ricoh Co., Ltd.

Claims (6)

[Claims] 1. A means for communicating with an external control means, an image data receiving means for receiving image data input via the communication means, a photoconductor carrying an electrostatic latent image, and a light exposure based on the received image data. Means for forming an electrostatic latent image on the body,
Developing means for a plurality of different colors for visualizing the electrostatic latent image on the photoconductor into a toner image, a toner image carrier for rotating adjacent to the photoconductor and holding the toner image on the photoconductor, a toner image carrier First transfer means for transferring the toner image on the photoconductor to the recording medium, second transfer means for transferring the toner image on the toner image carrier to the recording medium, and fixing means for fixing the toner on the recording medium to the recording medium A printer control unit for controlling the image forming operation of each color, the toner image is transferred to the toner image carrier by the first transfer unit once, and a plurality of image data are superimposed on the toner image carrier. In the step of forming an image and forming a desired superimposed toner image on the recording medium by the second transfer means, after the transfer to the toner image carrier is completed, an image is formed based on the next image data. Until the start
An image forming apparatus, wherein operation is controlled so as to stop the circumferential movement of a toner image carrier. 2. In the step of forming a superposed image on the toner image carrier with laser exposure means including a polygon motor as the electrostatic latent image forming means, after the transfer to the toner image carrier is completed, 2. The image forming apparatus according to claim 1, wherein the operation is controlled so that the driving of the polygon motor is stopped until the start of image formation based on the image data. 3. A means for detecting the time from the start of the transfer of the first image data to the start of the image formation, and based on the time detected by the detection means, until the start of the image formation by the second and subsequent image data. 3. The image forming apparatus according to claim 2, wherein the rotation of the polygon motor is controlled so as to be started up to a normal rotation. 4. A means for detecting the time from the start of the transfer of the first image data to the start of image formation, and the number of times of transfer of the image data received from the external control means before the start of the transfer of the first image data and detected by said detecting means. The image forming apparatus according to claim 1, 2 or 3, further comprising: a unit for estimating an end time of the entire image forming process from time, and a unit for displaying the end time. 5. A means for variably controlling the fixing temperature is provided,
Before the start of the first transfer of the image data, the number of image data transfers is received from the external control means to control the temperature of the fixing means to a temperature lower than that for the fixing operation. The image forming apparatus according to claim 1, 2, 3 or 4, wherein the temperature of the fixing unit is controlled so as to return to the temperature during a predetermined fixing operation before it reaches the fixing unit. 6. A fixing means for detecting the time from the start of transfer of the first image data to the start of image formation, and receiving the number of times of transfer of image data from an external control means before the start of transfer of the first image data and fixing the image data. 6. The image forming apparatus according to claim 5, wherein the temperature of the fixing unit is controlled to be lower than that during the fixing operation, and the temperature of the fixing unit is controlled based on the time detected by the detecting unit and the number of times of image data transfer. .