JPH09265221A - Image recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve reliability, to simplify the constitution of a circuit and to decrease the cost by transferring image data from a controller with a single main-scan synchronizing signal, to reduce the number of signals transferred from the controller. SOLUTION: A host computer 20 transmits data of printer page prescribing language, etc., (in general, a postscript, etc., are known) to the printer controller 21. This printer controller 21 receives the image data by a command received from the host computer 20, expands the received image data into bit map data and simultaneously, transmits the bit map data to a printer engine 22, in synchronization with a synchronizing signal from the printer engine 22. In other words, the image data from the controller can be transferred with the single main-scan synchronizing signal. Thus, the number of the signals transferred from the controller can be reduced and the reliability can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording apparatus having a plurality of photoconductors and a plurality of optical writing units and having a controller externally or internally.

[0002]

2. Description of the Related Art As described in Japanese Patent Application Laid-Open No. 5-284314, by receiving a synchronization signal transmitted from an image transmitting device and transmitting an image signal and a clock in parallel, the image signal is transmitted to the image receiving device. It is known to refine the synchronization of the. An image recording device having a plurality of photoconductors and a plurality of optical writing units is generally used as a color image output device (hereinafter referred to as a color printer) that operates at high speed. This type of color printer has been in increasing demand in recent years as a printer for obtaining high-speed color copies in response to the need for color images in the office, and has also attracted attention in the field of light printing.

In a monochrome printer, an image is transferred from an image transmitting device (hereinafter referred to as printer controller) to an image receiving device (hereinafter referred to as printer engine) by a single synchronization signal, a single image transfer clock and an image signal. However, in a color printer having a plurality of photoconductors and a plurality of optical writing units, since toners of a plurality of colors are overlapped to output an image, a position control technique with higher accuracy than that of a monochrome printer is required. Therefore, in the color printer, it is necessary that each optical system has independent position accuracy by using a horizontal synchronizing signal (main scanning synchronizing signal) corresponding to each optical system of the plurality of optical writing units and an image writing clock.

The printer controller mentioned here has an image memory having a storage capacity of one page or more for communicating commands and image data with an external device such as a host computer, and the image memory has an image memory. A device that expands data and outputs commands and image data to the printer engine during image recording. The printer controller is inside the printer body and is integrated with the printer body (as is often the case with image recording devices that have only the printer function), and is located outside the printer body (copying with the printer function added). There are many machines and printing machines).

The printer engine referred to here is
An image forming system including a photoconductor and an optical system for recording an image,
An image data processing system that processes image data sent from the printer controller (the image data is finally converted into an optical signal by a light source such as a semiconductor laser) and a control system that controls these.

Color printers are generally yellow (hereinafter Y
), Magenta (hereinafter M), cyan (hereinafter C)
4), black (hereinafter referred to as K), is used as a base color, and a full-color image is output. For this reason, in a color printer, photoconductors and optical systems are required for the number of colors (generally four). Further, the color printer uses the horizontal synchronizing signal corresponding to each optical system as described above, and uses the image writing clock synchronized with each of these.

When this type of color printer records an image, the printer engine receives the image data from the printer controller. Generally, a printer controller has an image memory having a storage capacity of one page or more, but a printer engine does not have a memory having such a large storage capacity because of cost problems. Therefore, in the color printer, as in the example disclosed in Japanese Patent Laid-Open No. 5-284314, the printer engine uses a printer controller to generate a plurality of image data for a plurality of colors by using horizontal synchronization signals for a plurality of colors and image transfer clocks for a plurality of colors. Generally, the reception is performed in synchronization with the writing of the color image.

[0008]

In a color printer, a printer engine synchronizes image data of a plurality of colors with writing of an image of a plurality of colors by a horizontal synchronizing signal of the plurality of colors and an image transfer clock of the plurality of colors from a printer controller. Then, the horizontal synchronizing signals for the number of colors and the image transfer clocks for the number of colors are required. For this reason, the number of signals used for communication between both the printer controller and the printer engine increases, the interface between the printer controller and the printer engine becomes complicated, reliability decreases, and cost increases.

The present invention solves the above problems, reduces the number of signals transferred from the controller, improves reliability, and simplifies the circuit configuration and reduces the cost. It is an object to provide a recording device.

[0010]

In order to achieve the above object, the invention according to claim 1 is directed to a plurality of photoconductors and a light beam is generated on each of the plurality of photoconductors. It has a plurality of optical writing units for scanning and main scanning synchronization signal generating means for receiving the light beam of the optical writing units and generating a main scanning synchronization signal for determining an image writing timing in the main scanning direction. In an image recording apparatus provided with a controller externally or internally having a communication function of communicating with the outside and a function of expanding image data into a storage means and holding it in a storage means, an image is transmitted from the controller by a single main scanning synchronization signal. Data is transferred, the number of signals transferred from the controller can be reduced, reliability can be improved, and the circuit configuration can be simplified and It is possible to achieve a capital reduction.

According to a second aspect of the invention, a plurality of photoconductors are provided,
A plurality of optical writing units that generate a light beam on each of the plurality of photoconductors and scan the light beam, and determine the image writing timing in the main scanning direction by receiving the light beams of the optical writing unit. A main-scanning synchronization signal generating means for generating a main-scanning synchronization signal, and a controller having a communication function of communicating with the outside and a function of expanding and holding image data in a storage means in a bit map externally or internally. In the image recording apparatus provided for, the image data is transferred from the controller by a single image transfer clock, and the number of signals transferred from the controller can be reduced to improve reliability and a circuit. It is possible to simplify the configuration and reduce the cost.

According to a third aspect of the invention, a plurality of photoconductors are provided,
A plurality of optical writing units that generate a light beam on each of the plurality of photoconductors and scan the light beam, and determine the image writing timing in the main scanning direction by receiving the light beams of the optical writing unit. A main-scanning synchronization signal generating means for generating a main-scanning synchronization signal, and a controller having a communication function of communicating with the outside and a function of expanding and holding image data in a storage means in a bit map externally or internally. In the image recording apparatus provided for, the image data is transferred from the controller by a single main scanning synchronization signal and a single image transfer clock, and the number of signals transferred from the controller can be reduced and reliability is improved. And the simplification of the circuit configuration and the cost reduction can be achieved.

[0013]

2 is a schematic view of a printer engine according to an embodiment of the present invention. This embodiment is an embodiment of an image recording apparatus including a color laser printer, in which a printer engine includes an image station 1 (1K, 1Y, 1) including a photoconductor and an optical writing unit.
M, 1C). Note that K, Y, M, and C that follow the numbers and signal names of the components of this embodiment are black,
It represents yellow, magenta, and cyan, and what color the number or signal name before it is.

The constituent elements in each image station 1 are common to each color, and each image station 1 has an optical writing section 2 composed of a light source composed of a laser diode, a polygon mirror, etc., a photosensitive drum 3 serving as a photosensitive member, It has a developing device 4, a transfer roller 5 as a transfer means, a cleaning device 6, and a charger 7. A transfer bias is applied to the transfer roller 5 from a power source (not shown). Further, in this embodiment, the registration roller 8, the conveyor belt 9 and the fixing device 1 are used.
0, the conveyor belt 9 is spanned by the driving roller 11 and the driven roller 12 and is rotationally driven.

The developing device 4 (4 of each image station 1
(K, 4Y, 4M, 4C) contains a one-component developer of each color or a two-component developer of each color. Further, the recording paper is fed to the registration roller 8 from a paper feeding device (not shown) or the like, sent out to the conveyance belt 9 by the registration roller 8 at a predetermined timing, and conveyed by the conveyance belt 9.

In the image station 1K, the photosensitive drum 3K is rotationally driven in the sub-scanning direction by a motor, uniformly charged by the charger 7K, and then exposed by the optical writing unit 2K to write an image. An electrostatic latent image is formed 9. In the optical writing unit 2K, a light source including a laser diode is driven by K image data from the printer controller, the laser beam from the laser diode is scanned in the main scanning direction by the polygon mirror, and the laser beam from the polygon mirror is scanned. Is radiated onto the photoconductor drum 3K to form an electrostatic latent image on the photoconductor drum 3K.

The electrostatic latent image on the photosensitive drum 3K is developed into a K toner image by the developing device 4K, and this K toner image is transferred onto the recording paper on the conveyor belt 9 by the transfer roller 5K. Further, the photoconductor drum 3K is cleaned by the cleaning device 6K after the transfer of the K toner image to remove the untransferred toner.

In the image station 1Y, the photosensitive drum 3Y is rotationally driven in the sub-scanning direction by the motor, uniformly charged by the charger 7Y, and then exposed by the optical writing section 2Y to write an image. An electrostatic latent image is formed. In the optical writing section 2Y,
A light source including a laser diode is driven by Y image data from the printer controller, a laser beam from the laser diode is scanned in a main scanning direction by a polygon mirror, and the laser beam from the polygon mirror is applied to the photosensitive drum 3Y. Photoconductor drum 3Y
An electrostatic latent image is formed thereon.

The electrostatic latent image on the photosensitive drum 3Y is developed by the developing device 4Y into a Y toner image, and this Y toner image is superposed on the recording paper on the conveyor belt 9 by the transfer roller 5Y with the K toner image. Transcribed. Further, the photosensitive drum 3Y is cleaned by the cleaning device 6Y after the transfer of the K toner image to remove the untransferred toner.

In the image station 1M, the photosensitive drum 3M is rotationally driven in the sub-scanning direction by the motor, uniformly charged by the charger 7M, and then exposed by the optical writing section 2M to write an image. An electrostatic latent image is formed. In the optical writing section 2M,
A light source composed of a laser diode is driven by M image data from the printer controller, the laser beam from this laser diode is scanned in the main scanning direction by the polygon mirror, and the laser beam from this polygon mirror is applied to the photosensitive drum 3M. The photoconductor drum 3M
An electrostatic latent image is formed thereon.

The electrostatic latent image on the photosensitive drum 3M is developed by the developing device 4M to become an M toner image, and this M toner image is transferred onto the recording paper on the conveyor belt 9 by the transfer roller 5M. Transferred over the image. Further, the photosensitive drum 3M is cleaned by the cleaning device 6M after the transfer of the K toner image to remove the untransferred toner.

In the image station 1C, the photosensitive drum 3C is rotationally driven in the sub-scanning direction by a motor, uniformly charged by the charger CM, and then exposed by the optical writing section 2C to write an image. An electrostatic latent image is formed. In the optical writing section 2C,
A light source composed of a laser diode is driven by the image data of C from the printer controller, the laser beam from this laser diode is scanned in the main scanning direction by the polygon mirror, and the laser beam from this polygon mirror is applied to the photosensitive drum 3C. Photoconductor drum 3C
An electrostatic latent image is formed thereon.

The electrostatic latent image on the photosensitive drum 3C is developed by the developing device 4C to form a C toner image, and the C toner image is transferred onto the recording paper on the conveyor belt 9 by the transfer roller 5C. A full color image is formed by transferring the image and the M toner image in an overlapping manner. Also,
After the transfer of the K toner image, the photoconductor drum 3C is cleaned by the cleaning device 6C to remove the untransferred toner.

The recording paper on the conveyor belt 9 is the drive roller 1.
It is separated from the conveyor belt 9 at position 1, and the full-color image is fixed by the fixing device 10 and discharged to the outside. Each optical writing unit 2 is equipped with a synchronization detection unit that receives a laser beam from a polygon mirror at a predetermined position and generates a synchronization detection signal for determining the image writing timing in the main scanning direction.

FIG. 17 shows the structure of the optical writing section 2. In each optical writing unit 2, the laser light emitted from the light source 48 including a laser diode is condensed by the condenser lens 62, reflected by the polygon mirror 60, and scanned. The laser light from this polygon mirror 60 is fθ.
The photosensitive drum 3 is irradiated with light through the lens 63, and an electrostatic latent image is formed on the photosensitive drum 3. Further, the laser light from the polygon mirror 60 is reflected by the mirror 64 and guided to the synchronization detecting means 65 composed of a light receiving element, and the light receiving element 65 photoelectrically converts the laser light to perform a main scanning synchronization signal inside the printer engine which will be described later. Output (PLSYNC).

FIG. 1 shows the configuration of a system using this embodiment. The host computer 20 sends data such as a page description language for the printer (generally known as Postscript) to the printer controller 21. The printer controller 21 receives the image data by the command received from the host computer 20,
The received image data is expanded into bitmap data, and the bitmap data is sent to the printer engine 22 in synchronization with the synchronization signal from the printer engine 22. The printer engine 22 records the image data received from the printer controller 21 on the recording paper as described above.

FIG. 3 shows the image writing timing of each image station 1 of this embodiment. The overall recording operation will be described below with reference to FIG. In addition, in FIG.
~ T6 indicates a predetermined time. When a start signal is output from the printer controller 21 to the printer engine 22, the printer engine 22 feeds recording paper from a paper feeding device or the like. The recording paper is temporarily stopped at the registration roller 8, and the registration roller 8 is driven after a prescribed time T1 has elapsed from the rising of the start signal, whereby the recording paper is sent out by the registration roller 8 and conveyed by the conveyance belt 9. To be done.

A black image gate signal FGAT after a lapse of a predetermined time T2 from the start of driving the registration roller 8
When the EK is turned on, the image data is input from the printer controller 21 to the optical writing unit 2K of the printer engine 22 and the image data is recorded on the recording paper as described above (K toner image is recorded on the conveyor belt 9) Be transcribed to). A predetermined time T3 from when FGATEK is turned on
After the passage of time, the yellow image gate signal FGATEY is turned on, the image data is input from the printer controller 21 to the optical writing unit 2Y of the printer engine 22, and the image data is recorded on the recording paper as described above.

Similarly, the magenta image gate signal FGATEM is turned on after a predetermined time T4 has passed since FGATEY was turned on, and the printer controller 2
The image data is input to the optical writing unit 2M of the printer engine 22 from 1 and the image data is recorded on the recording sheet as described above, and the cyan image gate signal is generated after a predetermined time T5 has elapsed since the FGATEM was turned on. FGA
The TEC is turned on, image data is input from the printer controller 21 to the optical writing unit 2C of the printer engine 22, and the image data is recorded on the recording paper as described above.

As a result, on the recording paper, a toner image is recorded in the order of K, Y, M, and C to form a full-color image, and the fixing device 10 fixes the full-color image.
The image gate signals FGATEK, FGATEY,
FGATEM and FGATEC are turned on for T6 hours (about the same time), and T6 is the recording time for one page of a single color.

FIG. 4 shows the circuit configuration of the printer controller 21. The printer controller 21 is an MPU (Mic
a processing unit (ro processing unit) 30, an interface circuit unit 31 with the host computer 20, a frame memory 32, a memory control circuit unit 33, and an interface circuit unit 34 with the printer engine 22.
The MPU 30 communicates with the host computer 20 via the interface circuit section 31, and also expands the page description language data for the printer received from the host computer 20 via the interface circuit section 31 into bitmap data to generate the frame memory 32. Remember.

The MPU 30 develops the page description language data for the printer into bitmap data and expands it into the frame memory 3.
2 is completed, the printer engine 22 is communicated with via the interface circuit unit 34 to perform the recording operation of the bitmap data.
To be performed. The frame memory 32 includes K, Y, M,
Each color of C can be accessed independently. The memory control circuit unit 33 receives the synchronization signal FGA received from the printer engine 22 via the interface circuit unit 34.
The read address and timing of the frame memory 32 are controlled by TE, and the image data is written in and read from the frame memory 32 according to the instruction of the MPU 30.

FIG. 5 shows a circuit configuration of the interface circuit section 34. The interface circuit unit 34 is a FIFO
(First In First Out) Memory 35
With the number of colors (4). This FIFO memory 35 is
It has a storage capacity for storing image data for one line of a single color, writes and reads image data independently of each other asynchronously, and resets the write address by a write reset signal and resets the read address by a read reset signal. , A line memory having a function of writing write data by input of a write clock and reading read data by input of a read clock, and reading data in the order of writing. In FIG. 5, WRES is a synchronization signal C from the memory control circuit 33.
LSYNC is a terminal to which a write reset signal is input, and WCLK is a clock CVC from the memory control circuit 33.
Terminal where LK is input as write clock, RRES
Is a terminal to which the synchronizing signal LSYNC is input as a read reset signal from the printer engine 22, and RCLK is a terminal to which the clock VCLK is input as a write clock from the printer engine 22.

In the FIFO memory 35, a single LSYNC is input from the printer engine 22 as a read reset signal, and the image data is transferred to a single main scanning synchronization signal LSYNC.
Transfer to the printer engine 22 by C. Further, the interface circuit unit 34 transfers the FGATE from the printer engine 22 to the memory control circuit 33 as it is,
The communication signal between the MPU 30 and the printer engine 22 is passed as it is.

FIG. 6 shows a circuit configuration of the printer engine 22. In the printer engine 22, the MPU 40
Communicates with the MPU 30 of the printer controller 21 via the controller interface circuit unit 45,
It controls the operation of the printer engine 22. Operation panel 4
1 is used to perform various settings of the printer engine 22 such as online / offline and paper feed position,
The MPU 40 performs key input from the operation panel 41 and display control of the operation panel 41.

The driver circuit section 42 is controlled by the MPU 40 and drives a motor, a solenoid and the like related to the drive section of the printer engine 22. The printer engine driving motor 43 is driven by the driver circuit unit 42. Although only one motor 43 is shown in FIG. 6, in practice, a plurality of motors and solenoids are used in most cases, and motors and solenoids other than the motor 43 are not shown.

The synchronizing signal generator 44 generates a synchronizing signal used for processing and transferring image data, outputs it to the controller interface circuit 45 and the image data processor 46, and outputs synchronizing signals FGATE, LSYNC and PLSYNC.
The C, clocks VCLK, PVCLK are sent to the interface circuit section 34 of the printer controller 21 via the controller interface circuit section 45. In addition,
The synchronization signal generation unit 44 generates a main scanning synchronization signal for determining the image writing timing in the main scanning direction as a horizontal synchronization signal LSYNC in synchronization with the synchronization detection signal from the synchronization detection unit of the optical writing unit 2. The synchronization detection means of the writing section 2 and a part of the synchronization signal generation section 44 constitute main scanning synchronization signal generation means.

The image data processing unit 46 performs, for example, γ correction and image position adjustment on the image data received from the interface circuit unit 34 of the printer controller 21 via the controller interface circuit unit 45. The LD driver 47 drives each of the laser diodes (LDK, LDY, LDM, LDC) 48 of each optical writing section 2 by the image data of each color from the image data processing section 46. In each optical writing unit 2, the laser light from the laser diode 48 is received by the light receiving element 65 via the polygon mirror 60 and the mirror 64 as described above, and the synchronization detection is performed.

FIG. 7 shows a circuit configuration of the controller interface circuit section 45. The controller interface circuit unit 45 is a FIFO of the interface circuit unit 34.
A FIFO memory 49 having the same function as the memory 35 is provided, and four FIFO memories 49 (for the number of colors) are used.

The FIFO memory 49 includes a sync signal generator 4
4 receives the synchronization signal LSYNC as a write reset signal to reset the write address, and receives the synchronization signal PLSYNC from the synchronization signal generator 44 as a read reset signal to reset the read address. The clock VCLK from the generation unit 44 is input as a write clock to write the write data from the interface circuit unit 34 of the printer controller 21, and the clock PVCLK from the synchronization signal generation unit 44 is input as a read clock to read. Read the data.

Further, the controller interface circuit section 45 has the FGATE, LS from the synchronization signal generating section 44.
The YNC and the clock VCLK are transferred to the interface circuit unit 34 of the printer controller 21 as they are, and the communication signals between the MPU 30 and the MPU 40 of the printer controller 21 are passed as they are.

FIG. 8 shows a basic printer controller 21.
The transfer timing of one page of image data between the printer engine 22 and the printer engine 22 is shown. It should be noted that this timing is common to all colors, and colors are not particularly identified in FGATE and image data in the figure. Below, based on FIG. 8, a basic printer controller 21 and a printer engine 22
The transfer operation of image data for pages will be described.

When the MPU 40 of the printer engine 22 receives the print command from the MPU 30 of the printer controller 21, the recording paper is fed from the paper feeding device or the like, and the FGATE of each color is turned on at the designated timing.
One line cycle (one cycle of LSYNC) after the FGATE is turned on, the valid image data is transferred to the printer controller 2
1 to the printer engine 22. In other words, the number of main scanning lines of the actually recorded effective image is FGA.
If the time during which the TE is on is T6 and the line cycle is T8, the number of main scanning lines = T6 / T8-1.

FIG. 9 shows a basic transfer timing of image data for one main scanning line between the printer controller 21 and the printer engine 22. It should be noted that this timing is common to all colors, and colors are not particularly identified in VCLK and image data in the figure. The basic transfer operation of image data for one line of main scanning between the printer controller 21 and the printer engine 22 will be described below with reference to FIG.

After a predetermined time T9 has passed since LSYNC was turned on, the image transfer clock VCLK becomes active and the reading of image data from the frame memory 32 is started. Image data of 1 dot is transferred in one cycle V10 of VCLK. The image data is continuously transferred by the number (m) of pieces of image data on one line.
The FIFO memories 35 and 49 use the image transfer clock VCLK.
Since the image data read and write operations are performed only when the image transfer clocks CVCLK and PVCLK are input, only valid image data is transferred. Further, the image data is sent to the printer controller 21 by the single main scanning synchronization signal LSYNC.
From the printer engine 22 to the printer engine 22.

The timing of the image data transfer for this one line is represented by LSYNC and VCLK in FIG. 9, but LSYNC and VCLK are CLSYNC respectively.
The same applies when C and CVCLK are set and when LSYNC and VCLK are set to PLSYNC and PVCLK, respectively. However, the time T9 in which the generation of VCLK is delayed after inputting LSYNC has a unique value in each case.

FIG. 10 shows the transfer timing of the input / output image data of the interface circuit section 34 of the printer controller 21 and the input / output image data of the controller interface circuit section 45 of the printer engine 22.
Note that this timing is common to all colors.
Colors are not identified in LK and image data. In addition, T11 and T12 in the drawing indicate predetermined timings, and each image station 1 has a unique value (by color). The image data transfer operation of the interface circuit units 34 and 45 at the time of recording will be described below with reference to FIG.

After FGATE turns on and CLSYNC turns on, the frame memory 32 outputs the image data of the first line (image data 1), and the FIFO memory 3
5 is input. The image data input to the FIFO memory 35 is stored in the FIFO memory when CLSYNC is turned on thereafter.
The data is read from the memory 35 (image data 2) and input to the FIFO memory 49 at substantially the same timing. FI
The image data input to the FO memory 49 is the next PLS.
After YNC is turned on, it is read out (image data 3) and processed by the image data processing unit 46, and the LD driver 47
Is converted into a drive signal for the LD 48 and drives the LD 48.

As described above, according to the first embodiment of the present invention, a plurality of photoconductors 1 and a light beam are generated on each of the plurality of photoconductors 1 to generate the light beam. A plurality of optical writing units 2 for scanning the optical writing unit, and a main scanning synchronization signal generating unit that receives the light beam of the optical writing units 2 and generates a main scanning synchronization signal for determining an image writing timing in the main scanning direction. And a printer controller 21 as a controller having a communication function of communicating with an external host computer 20 and a function of expanding image data into a frame memory 32 as a storage unit and holding it in a frame memory 32. In the apparatus, since the image data is transferred from the controller 21 by a single main scanning synchronization signal LSYNC, the signal transferred from the controller is transmitted. It can be simplified and cost reduction of the circuit configuration it is possible to improve the reliability can reduce the number of.

FIG. 11 shows the circuit configuration of the interface circuit section of the printer controller according to the third embodiment of the invention. In this embodiment, in the embodiment of the invention according to claim 1, the interface circuit section 34 of the printer controller 21 and the controller interface circuit section 45 of the printer engine 22 have circuit configurations as shown in FIGS. 11 and 12. It is a thing. The interface circuit unit 34 shown in FIG.
The number of O memories 35 is equal to the number of colors (four), and the FIFO memory 35 has the same function as the FIFO memory 35 of the interface circuit unit 34 in the embodiment of the invention according to claim 1.

The FIFO memory 35 includes a single image transfer clock VC from the sync signal generator 44 of the printer engine 22 via the controller interface circuit 45.
LK is input as a read clock, and the input / output of other synchronizing signals, clocks and communication signals is the interface circuit unit 3 in the embodiment of the invention according to claim 1.
4 FIFO memory 35. Thus, F
In the IFO memory 35, the image transfer clock VCLK is common for each color, and the image data is sent as a single main scanning synchronization signal LSY.
Transfer to the printer engine 22 by the NC and the single image transfer clock VCLK.

FIG. 12 shows a circuit configuration of the controller interface circuit section 45 in this embodiment. FIG.
The controller interface circuit unit 45 shown in FIG.
The FO memory 49 has the same number (four) as the number of colors, and the FIFO memory 49 is the FIFO of the controller interface circuit unit 45 in the embodiment of the invention according to claim 1.
It has the same function as the memory 49.

The FIFO memory 49 receives a single image transfer clock VCLK as a write clock from the sync signal generator 44 of the printer engine 22, and inputs and outputs other sync signals, clocks and communication signals.
This is the same as the FIFO memory 49 of the controller interface circuit unit 45 in the embodiment of the invention according to.

In this embodiment, the transfer timing of the image data for one page between the basic printer controller 21 and the printer engine 22 (corresponding to FIG. 8) and the basic timing between the printer controller 21 and the printer engine 22. Transfer timing of image data for one main scan line (corresponding to FIG. 9), input / output image data of the interface circuit unit 34 of the printer controller 21, and input / output image data of the controller interface circuit unit 45 of the printer engine 22. Transfer timing (Fig. 10
(Corresponding to the above) and each image data transfer operation are the same as those of the embodiment of the invention according to claim 1.

As described above, according to the third embodiment of the invention, a plurality of photoconductors 1 and a light beam are generated on each of the plurality of photoconductors 1 to generate the light beam. A plurality of optical writing units 2 for scanning the optical writing unit, and a main scanning synchronization signal generating unit that receives the light beam of the optical writing units 2 and generates a main scanning synchronization signal for determining an image writing timing in the main scanning direction. And a printer controller 21 as a controller having a communication function of communicating with an external host computer 20 and a function of expanding image data into a frame memory 32 as a storage unit and holding it in a frame memory 32. In the apparatus, the image data is transferred from the controller 21 by the single main scanning synchronization signal LSYNC and the single image transfer clock VCLK. , It can be simplified and cost reduction of the circuit configuration it is possible that enhance can be by reliable to reduce the number of signals to be transferred from the controller.

FIG. 13 shows the circuit configuration of the interface circuit section of the printer controller in one embodiment of the invention according to claim 2. In this embodiment, the interface circuit unit 34 of the printer controller 21 in the embodiment of the invention according to claim 3 has a circuit configuration as shown in FIG. The interface circuit unit 34 shown in FIG. 13 has flip-flops (hereinafter referred to as F / F) 50 for the number of colors (four).

The F / F 50 is the printer engine 22.
The image data read out and input from the frame memory 32 at the rising edge of the single image transfer clock VCLK input from the synchronization signal generating unit 44 via the controller interface circuit unit 45 is latched, and the latched image data is latched. Is output to the controller interface circuit section 45 of the printer engine 22. Therefore,
The F / F 50 sends the image data to a single image transfer clock V
It is transferred to the printer engine 22 by CLK. Also,
The interface circuit unit 34 includes the printer engine 22.
To the memory control circuit 33 as it is, and the communication signal between the MPU 30 and the printer engine 22 is passed as it is.

FIG. 14 shows the transfer timing of one page of image data between the basic printer controller 21 and printer engine 22 in this embodiment. In addition, this timing is common to all colors.
Colors are not identified in TE and image data. Figure 1 below
A basic transfer operation of image data for one page between the printer controller 21 and the printer engine 22 will be described with reference to FIG.

When the MPU 40 of the printer engine 22 receives the print command from the MPU 30 of the printer controller 21, the recording paper is fed from the paper feeding device or the like, and the frame gate signal FGA of each color is fed at the designated timing.
Turn on TE. FGATE is the main scanning synchronization signal LSY
It is turned on in synchronization with NC, and immediately after FGATE is turned on, valid image data is input from the printer controller 21 to the printer engine 22. That is, in the present embodiment, the number of main scanning lines of the actually recorded effective image is as follows: number of main scanning lines = T6 / T8, where T6 is the time during which FGATE is on and one line cycle is T8. Become.

FIG. 15 shows the transfer timing of image data for one line of main scanning between the printer controller 21 and the printer engine 22. Note that this timing is common to all colors, and colors are not particularly identified in the image data in the figure. A basic transfer operation of image data for one line of main scanning between the printer controller 21 and the printer engine 22 will be described below with reference to FIG.

After a predetermined time T9 has passed since LSYNC was turned on, the image transfer clock VCLK becomes active and the reading of the image data 1 from the frame memory 32 is started. This image data 1 is F / F
The image data 2 latched by the F / F 50 and output from the F / F 50 has one cycle V1 of VCLK with respect to the image data 1.
The image data has been sent.

As each image data, one dot of image data is transferred in one cycle V10 of VCLK as in the embodiment of the invention according to claim 1 and the embodiment of the invention according to claim 3 above. It This image data transfer is 1
The number of image data of lines (m) is continuously performed. The timing of the image data 3 output from the PLSYNC, PVSYNC, and controller interface circuit unit 45 is the same as that of the first embodiment of the invention according to claim 1.

FIG. 16 shows the transfer timing of the input / output image data of the interface circuit section 34 of the printer controller 21 and the input / output image data of the controller interface circuit section 45 of the printer engine 22.
Note that this timing is common to all colors, and colors are not particularly identified in the image data in the figure. In addition, T12 in the figure is
It indicates a predetermined timing and has a unique value (by color) for each image station 1. The image data transfer operation during recording will be described below with reference to FIG.

Immediately after the FGATE is turned on, the image data of the first line (image data 1) is output from the frame memory 32 and input to the F / F 50. The image data input to the F / F 50 is latched in the F / F 50 at the subsequent rise of VCLK (image data 2) and input to the FIFO memory 49 at substantially the same timing. The image data input to the FIFO memory 49 is the next PLSYNC.
Is turned on and is read (image data 3), processed by the image data processing unit 46, converted into a drive signal for the LD 48 by the LD driver 47, and drives the LD 48.

As described above, according to one embodiment of the invention of claim 2, a plurality of photoconductors 1 and a light beam are generated on each of the plurality of photoconductors 1 to generate the light beam. A plurality of optical writing units 2 for scanning the optical writing unit, and a main scanning synchronization signal generating unit that receives the light beam of the optical writing units 2 and generates a main scanning synchronization signal for determining an image writing timing in the main scanning direction. And a printer controller 21 as a controller having a communication function of communicating with an external host computer 20 and a function of expanding image data into a frame memory 32 as a storage unit and holding it in a frame memory 32. In the apparatus, since the image data is transferred from the controller 21 by a single image transfer clock, the number of signals transferred from the controller can be reduced. It can be simplified and cost reduction of the circuit configuration it is possible to be improved can be with reliability. Further, as compared with the embodiment of the invention according to claim 1 and the embodiment of the invention according to claim 3, the F /
Since the image data is transferred using F, the cost can be further reduced.

The invention according to each claim is not limited to the above-described embodiment, and for example, the printer controller 21 may be provided outside in the above-described embodiment.

[0067]

As described above, according to the first aspect of the present invention, a plurality of photoconductors and a plurality of light beams for generating light beams on the respective photoconductors and scanning the light beams are provided. It has a writing section and a main scanning synchronization signal generating means for receiving the light beam of the optical writing section and generating a main scanning synchronization signal for determining the image writing timing in the main scanning direction, and communicates with the outside. In an image recording apparatus having an external or internal controller having a communication function and a function for expanding and holding the image data in a storage means in a bitmap, the image data is transferred from the controller by a single main scanning synchronization signal. , The number of signals transferred from the controller can be reduced, the reliability can be improved, and the circuit configuration can be simplified and the cost can be reduced.

According to the second aspect of the present invention, a plurality of photoconductors, a plurality of optical writing units for generating a light beam on each of the plurality of photoconductors and scanning the light beam, and a plurality of the optical writing units. A main scanning synchronization signal generating means for receiving the light beam of the writing unit and generating a main scanning synchronization signal for determining an image writing timing in the main scanning direction; and a communication function and image data for communicating with the outside. In an image recording apparatus having an external or internal controller having a function for expanding and holding a bit map in the storage means, since image data is transferred from the controller by a single image transfer clock, a signal transferred from the controller The number can be reduced, the reliability can be improved, and the circuit configuration can be simplified and the cost can be reduced.

According to the third aspect of the present invention, a plurality of photoconductors, a plurality of optical writing units for generating a light beam on each of the plurality of photoconductors and scanning the light beam, and a plurality of the optical writing units. A main scanning synchronization signal generating means for receiving the light beam of the writing unit and generating a main scanning synchronization signal for determining an image writing timing in the main scanning direction; and a communication function and image data for communicating with the outside. In an image recording apparatus provided with a controller having a function of expanding and holding a bit map in a storage means, the image data is transferred from the controller by a single main scanning synchronization signal and a single image transfer clock. Therefore, it is possible to reduce the number of signals transferred from the controller, improve the reliability, simplify the circuit configuration, and reduce the cost. Door can be.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration example of a system using an embodiment of the invention according to claim 1;

FIG. 2 is a schematic diagram showing a printer engine in the same embodiment.

FIG. 3 is a timing chart showing an image writing timing of each image station of the embodiment.

FIG. 4 is a block diagram showing a circuit configuration of a printer controller in the embodiment.

FIG. 5 is a block diagram showing a circuit configuration of an interface circuit unit in the same embodiment.

FIG. 6 is a block diagram showing a circuit configuration of a printer engine in the embodiment.

FIG. 7 is a block diagram showing a circuit configuration of a controller interface circuit unit in the same embodiment.

FIG. 8 is a timing chart showing a transfer timing of one page of image data between the basic printer controller and the printer engine in the embodiment.

FIG. 9 is a timing chart showing a basic transfer timing of image data for one main scanning line between the printer controller and the printer engine in the embodiment.

FIG. 10 is a timing chart showing a transfer timing of input / output image data of the interface circuit unit of the printer controller and input / output image data of the controller interface circuit unit of the printer engine in the embodiment.

FIG. 11 is a block diagram showing a circuit configuration of an interface circuit unit of a printer controller according to an embodiment of the invention as claimed in claim 3;

FIG. 12 is a block diagram showing a circuit configuration of a controller interface circuit unit in the same embodiment.

FIG. 13 is a block diagram showing a circuit configuration of an interface circuit unit of a printer controller according to an embodiment of the invention as claimed in claim 2;

FIG. 14 is a timing chart showing the transfer timing of image data for one page between the basic printer controller and the printer engine in the embodiment.

FIG. 15 is a timing chart showing a transfer timing of image data for one main scanning line between the printer controller and the printer engine in the embodiment.

FIG. 16 is a timing chart showing transfer timings of input / output image data of the interface circuit unit of the printer controller and input / output image data of the controller interface circuit unit of the printer engine in the embodiment.

FIG. 17 is a block diagram showing a configuration of an optical writing unit in the above embodiment.

[Explanation of symbols]

 1 Image Station 2 Optical Writing Unit 3 Photosensitive Drum 4 Developing Device 5 Transfer Roller 7 Charger 9 Conveyor Belt 20 Host Computer 21 Printer Controller 22 Printer Engine 30 MPU 32 Frame Memory 33 Memory Control Circuit Unit 34 Interface Circuit Unit 35, 49 FIFO Memory 45 Controller interface circuit 50 F / F

Claims (3)

[Claims] 1. A plurality of photoconductors, a plurality of optical writing units that generate a light beam on each of the plurality of photoconductors, and scan the light beams, and receive the light beams of the optical writing unit. And a main scanning synchronization signal generating means for generating a main scanning synchronization signal for determining an image writing timing in the main scanning direction, and a communication function for communicating with the outside and image data are expanded into a bit map in the storage means. An image recording apparatus having a controller externally or internally having a function of holding the image data, wherein image data is transferred from the controller by a single main scanning synchronization signal. 2. A plurality of photoconductors, a plurality of optical writing units that generate a light beam on each of the plurality of photoconductors, and scan the light beams, and receive the light beams of the optical writing unit. And a main scanning synchronization signal generating means for generating a main scanning synchronization signal for determining an image writing timing in the main scanning direction, and a communication function for communicating with the outside and image data are expanded into a bit map in the storage means. An image recording apparatus having an external or internal controller having a function of holding the image, wherein image data is transferred from the controller by a single image transfer clock. 3. A plurality of photoconductors, a plurality of optical writing units that generate a light beam on each of the plurality of photoconductors, and scan the light beams, and receive the light beams of the optical writing unit. And a main-scanning synchronization signal generating means for generating a main-scanning synchronization signal for determining the image writing timing in the main-scanning direction, and a communication function for communicating with the outside and image data are expanded into a bit map in the storage means. In an image recording apparatus having a controller having a function of holding the same, the image recording apparatus transferring image data from the controller by a single main-scanning synchronization signal and a single image transfer clock. ..