JP2840305B2 - Recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a recording apparatus for recording an image or the like based on input data.

[Conventional technology]

Since electrophotographic printers can perform high-resolution and high-quality printing, many printers such as laser printers, LED printers, and liquid crystal printers have recently been developed and widely used. Taking advantage of its high-quality features, complex figures and images are output.

A controller (for example, a PostScript controller) that outputs a complicated figure over one page of a printing surface requires at least one page of image memory (hereinafter referred to as a page memory). For example, printing A4 size paper at a resolution of 300 dpi requires a page memory of 1 Mbyte.

The amount of image information output from such a high-quality printer is considerably large. For this reason, image data handled on a memory device of a computer or another information processing device system is
It is often coded or programmed data rather than raw raster image data.

How quickly the coded image information for one page is converted to raster image information for one page for printing represents the performance of the page printer.

A conventional example of the control mode of this page printer is shown below.

FIG. 2 is a cross-sectional view of a typical laser beam printer among page printers. FIG. 3 is a simplified block diagram of the control circuit of the laser printer. In FIG. 3, reference numeral 25 denotes an information processing device (for example, a personal computer or a workstation) outside the laser printer. Reference numeral 27 denotes an external interface (for example, Centronics or RS232C), which sends coded image information (for example, ASCII code; hereinafter, these are referred to as code information) to the laser printer. The code information is received by the interface circuit section 18 in the laser printer. The microprocessor 17 receives the code information received by the interface circuit 18 via the internal bus 28. This internal bus 28 is a combination of a data bus address bus and a control bus. Further, the microprocessor 17 operates according to a control program in the memory 21. Note that the memory 21 is a nonvolatile ROM.

The microprocessor 17 processes the code information obtained from the interface circuit 18 to some extent and stores it in the memory 19. The memory 19 is a RAM for storing code information. Microprocessor 17 sequentially converts code information received from the outside into RA
At the same time, the code information is converted into dot image information and stored in the RAM 20. The RAM 20 is a memory for storing image data (bit map memory).
A DMA controller 22 reads data stored in the RAM 20 and sends the data to a raster conversion circuit 24. DMA controller 22 can occupy internal bus 28 independently of microprocessor 17. Microprocessor 17
When it is detected that the image data stored in the RAM 20 has reached one page (that is, when it is detected that all the code data of one page has been converted into image data), the DMA controller 22 is activated. The DMA controller 22 occupies the internal bus alternately with the microprocessor 17. Then, in response to a request from the raster conversion circuit 24, the DMA controller 22 sequentially reads out image data from the RAM 20 and sends the image data to the raster conversion circuit 24. The raster conversion circuit 24 converts the parallel image data received from the DMA controller 22 into serial image data. Then, serial image data is output to a laser driver (not shown) in synchronization with the horizontal synchronization signal, and modulates the laser beam.

The microprocessor 17 not only develops the code data into image data, but also issues commands for various printing processes to a mechanical control unit 26 of the laser printer. I / O
The driver 23 is a microprocessor 17 and a mechanical control unit.
Interfacing with 26.

Next, regarding the mechanical control of the laser printer, the second
The description will be made with reference to the drawings. In FIG. 2, reference numeral 1 denotes a main body of the laser printer. The microprocessor 17 develops the code data for one page, and when the processing for storing the image data in the memory 20 is completed, the microprocessor 17 rotates a transport motor (not shown) via the I / O driver 23. At this time, the photosensitive drum 2, the primary charging roller 5, the developing roller 7, the transfer roller 10,
The fixing roller 15 and the discharge roller 16 start rotating. The rotation control of the transport motor is performed by a mechanical control unit 26.

Reference numeral 3 denotes a laser scanning device, in which a laser scanning mirror, a laser scanning motor, a laser light emitting element, and a laser driving circuit are provided. The I / O driver 23 rotates the transport motor and also rotates the laser scanning motor inside the laser scanning device 3. Then, the I / O driver 23 sequentially applies a high voltage to the primary charging roller 5, the developing roller 7, and the transfer roller 10. Also, the I / O driver 23 turns on the clutch attached to the paper feed roller 12 to feed the paper 13 loaded on the paper cassette 14. The fed paper is stopped by the registration rollers 11. And the mechanical control unit 26 is I / O
The paper 13 fed to the driver 23 is
The microprocessor 17 sets the DMA controller 22 in an active state at the time when the paper 13 notifying the arrival of the data has stopped at the registration roller 11. Then, serial image data is transmitted from the raster conversion circuit 24. The transmitted serial image data is input to the laser scanning device 3, and the photosensitive drum 2 is irradiated with a laser beam modulated by the image data. Then, a latent image is formed on the surface of the photoreceptor, and is visualized as a toner image by the developing unit 6.

The paper stopped by the registration rollers 11
The toner image is conveyed by the transfer roller 11 and transferred to the paper by the transfer roller 10. Then, the paper to which the toner has adhered is thermally fixed by the fixing roller 15 and then discharged outside the apparatus by the discharge roller 16. The toner not transferred to the paper by the transfer roller 10 is collected in the cleaner 9.

As described above, the code information given from the external information processing device is printed on the sheet as image information.

When printing many pages of data, printing is performed at the timing shown in FIG. In FIG.
At the timing (a), the microprocessor 17 starts receiving the code data. At the same time, the microprocessor 17 starts turning the image, and stores the image data in the RAM 201. When the reception of the code data of the first page is completed at the timing (b), the reception of the code data of the second page is started at the timing (C). And (d)
If the image development of the first page is completed at the timing of
At this time, the conveyance motor is rotated to perform the sheet feeding operation at the timing of (f). Then, the registration roller 11 is driven at the timing (g), reading of image data by the DMA controller 22 is started at the timing (h), and serial image data is formed by the raster conversion circuit 24 at the timing (h). Then, laser exposure is started. Then, the laser exposure for the first page ends at the timing of (i). Similarly, the image development of the second page starts at the timing (i). After that, 2 in the same sequence as the first page
The printing operation of the page is performed.

In FIG. 4, a period during which image development is performed and a period during which image data is read (this is also a period during laser exposure).
Are completely independent and have no overlap period. This is because the image memory has only one page. If there are two pages of image memory, an overlap period can be provided.

[Problems to be solved by the invention]

In this method, no access to the image memory 20 is performed during the period from (f) to (h) (or during the period from (k) to (m)). Therefore, in a printer in which the distance between the paper feed roller and the registration roller is very long, the throughput (the number of prints per unit time) is reduced. If there are two pages of image memory,
The image development period and the image data readout period overlap,
Throughput can be improved. However, in that case, the memory cost is doubled.

As described above, the method of performing the sheet feeding operation after the image development for one page is completed has a disadvantage that the throughput is not improved by the arrangement of the sheet feeding unit.

In addition, a method of feeding paper before the completion of image development is also conceivable, but it is not possible to realize the maximum throughput of the recording apparatus and achieve a sufficient throughput.

[Means and Actions for Solving the Problems] In order to achieve the above object, a recording apparatus according to the present invention comprises: a conversion unit for converting information from a higher-level device into pixel information; Eye information or 2
Output means for outputting a signal to start feeding of the recording medium after completion of reception of the information of the page and before completion of conversion into pixel information, regardless of the information of the page and thereafter; Paper feed means for feeding paper, and control means for controlling driving of a photoconductor on which an image to be transferred is formed on the fed print medium, wherein the control means starts feeding of the print medium When the signal is output while the photoconductor is being driven for the recording of the previous page, the recording medium is fed to a predetermined standby position while the driving of the photoconductor is continued. If it is output when not driven, the drive of the photoconductor is started and the recording medium is fed to the standby position.

Preferably, when the standby state of the recording medium at the standby position continues for more than a predetermined time, the control unit stops driving the photoconductor.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As described with reference to FIG. 4, when the printing operation is performed by using the image memory for one page, the throughput usually decreases. However, a method for preventing the throughput from decreasing by using the image memory for one page will be described. It is shown in FIG. Note that the configuration of the device (hardware) itself can be the same as that of the conventional example, and thus the description is omitted here.

In FIG. 5, it is assumed that the microprocessor 17 starts the reception of the code data at (a) and ends the reception of the first page at the timing of (b). At this time, the microprocessor 17 rotates the transport motor and the laser scanning motor, and after a while, causes the sheet feeding operation to be performed at the timing (c).

Then, assume that the code data of the second page is received at the timing (d), and the reception is completed at the timing (m). Assuming that the microprocessor 17 has finished developing the image of the first page at the timing (e), the registration roller 11 is driven at the timing (f). Then, the image data is read (laser exposure) at the timing (g), and the reading is completed at the timing (i).
Similarly, image development of the second page is started at the timing (i). In FIG. 5, before the reading of the image of the first page (laser exposure) is completed, the feeding operation of the second page is performed ((h)).
Timing). Then, the image development of the second page is completed at the timing of (j), and 2
Print the page. The feature of this method is that, unlike FIG. 4, image development and laser exposure are performed from the sheet feeding operation to the driving of the registration roller. Thus, it can be seen that the dead time can be reduced and the throughput can be improved. Even if the distance from the paper feed roller to the registration roller becomes long, the throughput can be prevented from lowering by increasing the timing of feeding the second and subsequent pages (ie, by increasing the timing of (h)).

In the method of FIG. 5, after the code information has been expanded (1
The paper feed operation is performed (after receiving pages), and the registration roller is driven after the image development is completed.

If the time for image development is short, the registration roller can be driven immediately after the paper feed operation is performed and the paper reaches the registration roller. Conversely, if the image development time is long, the fed paper must be stopped for a long time by the registration roller.

During this time, a high pressure is applied to the photosensitive drum, and the photosensitive drum keeps rotating. Therefore, when developing complicated graphic information and the like, the photoconductor drum continues to rotate for a long time, and there has been a problem that the photoconductor drum is greatly worn.

Second Embodiment Next, a description will be given of a second embodiment in which the throughput is improved and wear and the like of the photosensitive drum are minimized.

Also in the second embodiment, the hardware configuration is the same as the conventional one, and the control method is different from the conventional one. Therefore, the control method will be described here. Fig. 1-1, 1st
2, FIG. 1-3, and FIG. 1-4 are control flowcharts of the electrophotographic printer of the present embodiment. FIG. 1-1 shows a routine for performing the main control. FIG. 1-2 shows a "code data receiving task" started by the main control routine (FIG. 1-1). In FIG. 1-2, a process of receiving code data from an external information processing device and storing the data in the code storage memory 19 is performed. FIG. 1-3 shows an "image developing task" started by the main control routine (FIG. 1-1). 1-3
In the figure, the code data stored in the code storage memory 19 is read, the code data is converted (developed) into image data, and the image data is stored in the image data storage memory 20.

FIG. 1-4 shows an "image forming task", which is a routine that can be started by the main control routine (FIG. 1-1) every time one page is printed. These control flows will be described in detail below. Referring to FIG. 1-1, first, the microprocessor 17 sets a paper feed permission flag (step S1-1-a). This flag is used in the main control routine and the image forming task, and is a flag for determining the timing for feeding the paper stacked on the paper cassette.
Then, the code data receiving task is started (step S1-
1-b) Then, the image development task is started (step S1).
-1-c). When the "code data reception task" is activated, first, the reception of the code data from the external information processing device is prohibited (step S1-2-a). Then, it is checked whether the page clear designation has been output from the "image forming task" (step S1-2-b). This page clear designation means that the “image forming task” ends the printing operation,
This means that the data of the completed page is erased from the code memory 19. If the page clear designation has been output, the code data corresponding to the designated member is cleared (step S1-2-s). Next, it is checked whether the data stored in the code memory 19 is full and an empty area of the code memory exists (step S1-2).
-D). If the code memory is full, the process returns to the beginning of the task without doing anything. If there is an empty area in the code memory, the reception of the code data from the external information processing device is permitted (step S1-2-e). Then, it is checked whether a predetermined byte of code data has been received (step S1-2-f), and if received, the received data is stored in an empty code memory area (step S1-2-y). . Then, it is checked whether or not the received code data has reached one page (step S1-2-).
h), permit printing to the main control routine (step S1-2-i).

As described above, in the “code data reception task”, if there is an empty area in the code memory 19, the code data is received, and if the code data memory 19 is full, the reception is stopped.
When the code memory for one page is saved, a print command is output to the main control routine. When the image formation for one page is completed, the code data corresponding to the completed image is deleted from the code memory 19.

In the "image development task", the code data stored in the code memory is developed into image data. In FIG. 1-3, the microprocessor 17 searches the data stored in the code memory area for the oldest page on which the image has not been developed yet (step S1-3-a). Then, code data which has not been developed in the image is searched in the page (step S1-3-b). Then, the code data is image-developed and stored in the image memory 20 (step S1-3).
-C). Next, it is checked whether or not the image development of the page has been completed (step S1-3-d), and if completed, the information that the image has been developed is notified to the main program (step S1-3-e). . Otherwise, the image development of the page is continued. This image development is performed in parallel with the reception of the code data.

Once image development is completed, the next image data (dot data) is read by the DMA controller 22. Then, laser exposure is performed. The control is performed by an “image forming task”. The image development process and the laser exposure process are not performed simultaneously. This is because the image memory has only one page. Now, in step S1-3-f, the "image forming task"
Wait for the end of the laser exposure in. When the laser exposure of the page is completed, the "image developing task" returns to the beginning of the routine and starts developing the image of the next page.

In step S1-1-d, in the main control routine,
Check whether or not print permission has been received from the "code data reception task". If code data for one page is received from the external information processing device and printing of the page can be started, the transport motor and the laser scanning motor are rotated next (step S1-1-g). Otherwise, step S1
The control enters the determination routine of -1-e. In step S1-1-e, if the printed paper has already been conveyed in the printer,
It returns to step S1-1-d. Otherwise, the transport motor and the laser scanning motor are stopped, and (Step S1-1)
Return to d). In this way, if there is no print permission, the transport motor and the laser scanning motor are stopped. Step
After rotating the transport motor and the laser scanning motor in S1-1-g, the process waits until the motor stably rotates at the specified number of revolutions (step S1-1-h). Next, it is checked whether or not the paper feed permission flag has been set (step S1-1-i). This flag is reset at the beginning of the "image forming task", and is reset again during the image forming (step S1-4-1). This flag determines the paper feed interval for continuous printing. Step S1
If the paper supply permission flag is set at -1-i, the paper supply roller 12 is driven next to perform the cassette setting.
The paper loaded on 14 is fed (step S1-1-j).
Then, it waits until the fed paper reaches the registration roller 11 (step S1-1-k). At this point, it is checked whether or not the image development of the page to be printed has already been completed (step S1-1-1). This determination is based on the image development end information (step
Performed based on S1-3-e). If it has been completed, the "image forming task" is started (step S1).
-1-r).

If the image development has not been completed, the routine proceeds to a judgment routine (step S1-1-m). Then, it is checked whether the already printed paper is being conveyed in the printer (step S1-1-m). If the sheet is not conveyed into the apparatus, the conveying motor and the laser scanning motor are stopped (step S1-1-n). Then, it is checked again whether or not the image development has been completed in the "image development task" (step S1-1-o), and if not, the step is performed again.
Move to S1-1-m. This step S1-1-m, step
In the routine of S1-1-n and step S1-1-o,
If the printed paper is discharged to the outside of the apparatus before the image development is completed, the transport motor and the laser scanning motor stop when the paper is discharged. If the image development is completed before the paper is discharged out of the machine, the transport motor and the laser scanning motor are stopped. If there is no already printed paper, the operation immediately stops. Then, when the image development is completed, the transport motor and the laser scanning motor are rotated again (step S1-1-p). Then, wait until the transport motor and the laser scanning motor rotate at the specified number of revolutions (step S1-1).
q) and start the image forming task (step S1-
1-r).

Steps S1-1-l, S1-1-m, S1-1-o, S1-1-p, and S1-1
According to the routine of -q and step S1-1-r, if the timing at which the image development ends is earlier than the timing at which the paper reaches the registration rollers, the transport motor does not stop. In the opposite case, if the already printed paper is not in the printer, the transport motor stops once.
In this way, the transport motor and the laser scanning motor rotate or stop at the timing of the end of the image development.

When the "image forming task" is activated, a printing process of the page on which the image has been developed is performed. In FIG. 1-4, first, the paper feed permission flag is reset (step S1-4-).
a). This prevents the next page of paper from being fed during printing of a certain page. Then, the registration roller is driven. After a predetermined time, the primary charging high voltage is turned on (step S1-
4-d). Further, after a predetermined time, the DMA controller 22 is operated (step S1-4-f). Thereby, reading from the image memory is performed, and laser exposure is started. After a predetermined time from the start of the laser exposure, the developing high pressure is reduced.
It is turned on (step S1-4-h), and after a predetermined time, the transfer high voltage is turned on.

The time from when the registration roller is driven to the time when the primary charging high voltage is turned ON, the time from when the primary charging high voltage is turned ON until the laser exposure starts, and between the time when the laser exposure starts and the development high voltage is turned ON And the time from when the developing high voltage is turned on to when the transfer high voltage is turned on. These times are determined based on the position of each high voltage output and the position of the registration roller.

After the transfer high voltage is turned on, a sheet supply permission flag is set after a predetermined time (step S1-4-l). At this time, if the reception of the code data of the next page has been completed, the feeding operation of the next page is performed. This determination is made in (Step S1-1-d) and (Step S1-1-i) of the main control routine.

Now, in FIG. 1-4, after the paper feed flag is set,
After a predetermined time, the registration roller is stopped (step S1).
-4-m, Step S1-4-n, Step S1-4-n
o) Then, the primary charging high voltage, the laser exposure, and the developing high voltage transfer high voltage are sequentially turned off (Step S1-4-p to Step S)
1-4-v).

Finally, it is determined that the image formation has been completed, and the clear of the currently printed page is designated in the "code data receiving task" (step S1-4-w). Thus, the code memory area occupied by the data of the page is released, and the data can be received from the external information processing device.

This “image forming task” is a task started every time a certain page is printed. Next, the sequence of this embodiment (first
FIG. 6 shows an example of the operation timing chart of FIG.
It is shown in FIG. This example shows a case where the time required for image development is short. The reception of the code data starts at the timing of FIG. 6-1 (a), and when the reception of the first page ends at the timing of FIG. 6-1 (b), the transport motor (and the laser scanning motor) is rotated. . When it is detected that the motor is rotating stably, the supply operation is performed at the timing shown in FIG. Then, before the fed paper reaches the registration rollers, the image development is completed (No. 6-1).
Figure (c). Thus, the registration roller is driven at the timing shown in FIG. Thereafter, each high voltage and laser light are sequentially output. Then, before the laser exposure of the page is completed, the next page is fed.

Next, the case where the time required for image development is long is described in No. 6-2.
Shown in the figure. In FIG. 6-2, when the reception of the code data of the first page is completed at the timing of FIG. 6-2 (b), the transport motor (and the laser scanning motor) is driven. When it is detected that the motor is rotating stably, the paper feeding operation is started at the timing shown in FIG. 6D. If the image development is not completed at the timing when the fed paper reaches the registration roller, the transport motor is stopped once (FIG. 6E). When the image development is completed (FIG. 6-2 (f)), the transport motor is driven again. Then, the registration roller is driven when the transport motor rotates again stably (FIG. 6-2 (g)).

In FIG. 6-2, since the time required for image development is long,
The transport motor is stopped at the timing from (FIG. 6-2 (e)) to (FIG. 6-2 (g)).

On the first page, no high voltage is applied between the time when the sheet feeding operation is performed and the time when the registration roller is driven. For this reason, when the photosensitive drum stops at the timing shown in FIG. 6E, no charged charge remains on the surface of the photosensitive drum. When printing is performed continuously, a certain page is always printed, and after the paper is completely discharged, the photosensitive drum is stopped. Therefore, there is a state where each high-voltage output becomes zero and the photosensitive drum is rotated (from FIG. 6-2 (j) to FIG. 6-2 (k)). As a result, the photosensitive drum is stopped with the charge on the surface of the photosensitive member completely removed.

Therefore, in the sequence of the present embodiment, the photoconductor is not stopped while electric charges remain on the surface of the photoconductor, so that the photoconductor is not deteriorated. In the sequence of this embodiment, the throughput is not reduced when the time required for image development is short. If the time required for image development is very long, the shared motor is stopped. Thereby, wear of the photosensitive drum can be prevented as much as possible.

In the above example, if the image development is not completed at the timing when the fed paper reaches the registration roller, the transport motor is immediately stopped.However, the timing for stopping the transport roller may be somewhat delayed. I don't care.
If the stop timing of the transport roller is delayed, printing is often performed without stopping the transport motor, and the time during which the photosensitive drum is rotating becomes longer. Therefore, if the durability of the photoreceptor is good, the extension time can be extended.

[Third Embodiment] In a second embodiment, the paper fed once is transferred to a registration roller.
11 and stopped (see Fig. 7). FIG. 7 shows the paper transport system of FIG. This is because the position of the leading end of the image is adjusted by the registration roller 11. Then, the paper pressed against the registration roller 11 forms a loop as indicated by 31. If the conveyance motor or the registration roller is stopped for a long time in this state, the paper curls, causing printing failure. The third embodiment is an example in which the defect of the paper is removed. The structure of the device is shown in FIG. 8 differs from FIG. 7 in that a photo sensor (hereinafter referred to as a paper feed sensor 30) for detecting the leading edge of the paper is provided between the registration roller 11 and the transfer roller 10. The leading edge of the paper is detected by the paper feed sensor 30, and laser exposure is performed based on the detection timing.

The embodiment of FIG. 3 differs from the second embodiment in that the fed paper first forms a loop with the registration rollers 11 and does not stop. Instead, the fed paper is sandwiched by the registration rollers 11 as shown in FIG. 32, and does not form a loop.

Next, the control operation in the configuration of FIG. 8 will be described based on the time chart of FIG. In FIG.
After the sheet is fed at the timing of FIG. 9D, the registration roller 11 is turned on at the timing of FIG. 9E. Then, the registration roller is turned off at the timing shown in FIG. 9 (f).
I do. By newly providing the period from FIG. 9 (e) to FIG. 9 (f), paper can be inserted between the registration rollers.

After the image development is completed, the registration roller 11 is driven again (FIG. 9 (i)).
(FIG. 9 (j)). And (Fig. 9 (j))
The output of each high voltage and laser exposure are performed with reference to the timing of (1).

In the third embodiment, since the paper is stopped by being sandwiched between the registration rollers 11, the stop position of the paper varies, and a paper feed sensor 30 is provided to correct the variation.

In the above description, the laser scanning motor is stopped when the transport motor is stopped.
If the durability of the laser scanning motor is high, only the transport motor may be stopped.

Although the above embodiments have been described by taking a laser beam printer as an example, the present invention can also be applied to LED printers and liquid crystal printers. In the case of an LED printer, an LED array head is used instead of the laser scanning device, and in the case of a liquid crystal printer, a liquid crystal array head is used.

Fourth Embodiment In the first and second embodiments, the microprocessor 17
Has performed the mechanical control of the laser printer in addition to receiving the code data and developing the image into the code data. Therefore, the load on the microprocessor 17 is very large. In order to reduce the load on the microprocessor 17, there is a method in which mechanical control of the laser printer is assigned to another independent microcomputer.

FIG. 10 shows an example of the control circuit. The control circuit shown in FIG. 10 includes the I / O driver 23 shown in FIG.
6. The one corresponding to the raster conversion circuit unit 24 is mounted.
In FIG. 10, the mechanical control of the laser printer is performed by a single-chip microcomputer 40. The loads on the micro computer 40 include a motor driver 41, a laser scanning motor driver 43, a paper feed clutch 45, a transport clutch (not shown), a sensor 47, a high voltage output circuit 48, a laser modulation circuit 49, a beam detection circuit 51, and the like. The micro computer 40 controls each of the above loads according to a command from the I / O driver 23. There are a READY signal, a PRINT signal, a VSREQ signal, and a VSYNG signal between the micro computer 40 and the driver 23. In addition, a serial communication line for informing the I / O driver 23 of the load status of the printer and informing the micro computer 40 of a special command of the I / O driver 23 is also provided.

The image signal (VIDEO) output from the raster conversion circuit 24
O signal) is input to the laser modulation circuit 49, and the semiconductor laser 5
The laser light output from 0 is modulated according to the VIDEO signal. The laser beam is scanned by a laser scanning mirror, and the scanned laser beam is scanned by a photodiode.
It is incident on 52. Then, the laser beam is converted into a pulse signal by the beam detection circuit 51. The pulse signal output from the beam detection circuit 51 is a horizontal synchronization signal (HSYNC
) Is input to the raster conversion circuit 24.

Next, the state of these interface signals and the control method of the microcomputer 40 will be described with reference to FIG. When the READY signal is true and the microprocessor 17 has received one page of code data, the I / O driver 23 sets the VINT signal to t with the PRINT signal set to false.
Set to rue (Fig. 11 (a)). At this time, the micro computer 40 rotates the transport motor and the laser scanning motor (FIG. 11 (b)). Then, after a predetermined time,
Turn ON (Fig. 11 (c)).

When the microprocessor 17 completes image development for one page, the VSYNC signal is set to false and the PRINT signal is set to true.
Set to e (Fig. 11 (d)). Then, after the fed paper reaches the registration roller, the micro computer 40
The REQ signal is set to true (FIG. 11 (e)). This gives I
The / O driver 23 knows that the paper has reached the registration roller, and sets the VSYNC signal to true with the PRINT signal set to true (FIG. 11 (f)). Microcomputer 40 is the VS
Upon receiving the YNC signal true, the VSREQ signal is set to false at the timing shown in FIG. 11 (g).

Then, the micro computer 40 is connected to VSYN in FIG. 11 (f).
The registration roller is driven a predetermined time after receiving the true of the C signal (FIG. 11 (h)). And a microcomputer
40 turns on the primary charging high voltage (Fig. 11 (i)), turns on the developing high voltage
(FIG. 11 (k)), the transfer high voltage is turned ON (FIG. 11 (l)). The microprocessor 17 activates the DMA controller 22 at the timing shown in FIG. 11 (j) and outputs a VIDEO signal.

FIG. 11 shows the end of code data reception (FIG. 11 (a))
This is an example in the case where the time from the start to the end of the image development (FIG. 11D) is short, and corresponds to FIG. 6-1 of the second embodiment.

Next, FIG. 12 shows an example in which the time from the end of the reception of the code data to the end of the image development is long.

In FIG. 12, after the sheet feeding operation is performed at the timing of FIG. 12 (c), if the true of the PRINT signal cannot be detected after a predetermined time, the micro computer 40 turns off the motor once.
Set to F (Fig. 12 (d)). After that, when the image development is completed, the I / O driver 23 sets the VSYNC signal to false and sets the PRI
Set NT signal to true. Then, the microcomputer 40 turns on the motor again at the timing shown in FIG. 12 (f), and changes the VSREQ signal to O when the paper reaches the registration roller stably.
Set to N (Fig. 12 (g)). And I / O driver 23 is 12th
In FIG. 7H, the registration roller is driven, and then each high voltage is output.

FIG. 12 corresponds to FIG. 6-2 of the second embodiment. The above sequence PRINT signal, VSREO signal, VS
When the YNC signal is driven, the mechanical control is assigned to the single-chip microcomputer, and the same printing operation as in the second embodiment can be performed.

The above is the control method when the fed paper is pressed against the registration roller to form a loop on the paper. In the third embodiment, an example in which a loop is not formed in the fed paper has been described. Even in this case, the PRINT signal, VSREQ signal, VSYN
A command can be given to the single chip computer using the C signal. FIG. 13 shows a timing chart at that time. In FIG. 13, when the microprocessor 17 receives the code data for one page, the PRINT
Set the VSYNC signal to true while the signal is false.

Microcomputer 40 VSYNC when PRINT signal is false
When the signal receives true (FIG. 13 (a)), the motor is driven (FIG. 13 (b)) and the sheet feeding operation is performed (FIG. 13 (c)). After a predetermined time, the resist roller is driven (FIG. 13 (d)), and the registration roller is turned off once (FIG. 13 (e)). In this state, the fed paper is stopped between the registration rollers. If the PRINT signal does not become true after a certain period of time after the registration roller stops, the motor is turned off once (FIG. 13 (f)). Then, when the microprocessor 17 completes the image development, the VSYNC signal is set to false and the PRINT signal is set to true. Then, the microcomputer 40 turns on the motor again (FIG. 13 (h)) and drives the registration roller again (FIG. 13 (i)). Then, the paper sandwiched between the registration rollers is transported toward the paper feed unit sensor 30. When the leading end of the conveyed paper passes through the paper feed unit sensor 30, the microcomputer 40 sets the VSREQ signal to true (FIG. 13 (j)). I
The / O driver 23 and the microprocessor 17 output the VSREQ signal t
When rue is detected, a VIDEO signal is output in synchronization with the rise. The microcomputer 40 applies a high voltage sequentially in synchronization with the rise of the VSREQ signal.

If the PRINT signal and the VSYNC signal are driven in such a control procedure, the same control as in the third embodiment can be performed comprehensively.

In the fourth embodiment, the microprocessor 17 performs processing of receiving code data and developing an image, and the single-chip computer 40 performs paper conveyance and high-pressure control. And I / O driver 23 and microcomputer 40
Are connected by an interface signal. The feed operation and control of the paper transport roller are controlled by the PRINT signal, VSREQ
Signal and VSYNC signal are performed. These signals may be replaced with other serialized signals. That is, only serial communication is performed between the I / O driver 23 and the micro computer 40, and the microprocessor 17 and the I / O driver 23 use the coded information in the serial communication to execute the micro computer.
You can also control 40. It is also possible to make an external information processing device take charge of the process of receiving code data and developing an image.

In the electrophotographic printer of the embodiment described above, the ON / OFF control of the transport motor is performed based on the timing at which the image development of the code data to be printed is completed. This makes it possible to secure a high throughput when the image data is easily developed and the code data that can finish the development quickly is received. Conversely, when image data is complicated and the code data that requires a long developing time is received, the transport motor is stopped once, so that the photosensitive drum can be prevented from being worn.

Further, according to the sequence of the present embodiment, since the unnecessary charge does not remain on the surface of the photosensitive drum after the photosensitive drum is stopped, deterioration due to the unnecessary charge can be prevented.

〔The invention's effect〕

As described above, according to the present invention, regardless of whether or not the photoconductor is driven for recording the previous page, after the reception of the information of one page is completed and before the conversion to the pixel information is completed, A signal for starting the feeding of the recording medium is output, and when the signal is output while the photoconductor is being driven for the recording of the previous page, the driving of the photoconductor is continued while recording is performed. When the medium is fed to a predetermined standby position and output when the photoconductor is not driven, the drive of the photoconductor is started, and the recording medium is fed to the standby position. Throughput can be improved.

[Brief description of the drawings]

FIG. 1-1, FIG. 1-2, FIG. 1-3, and FIG. 1-4 show control flowcharts of the recording apparatus of the embodiment, FIG. 2 is a schematic sectional view of a laser printer, and FIG. FIG. 4 is a control circuit diagram of a laser printer, FIG. 4 is a diagram showing a timing chart of a conventional recording operation, FIG. 5 is a diagram showing a timing chart of a recording operation in the first embodiment, FIGS. −
FIG. 2 is a diagram showing a timing chart of a recording operation in the second embodiment, FIGS. 7 and 8 are diagrams for explaining a paper transport mode, and FIG. 9 is a timing chart of a recording operation in the third embodiment. FIG. 10 is a control circuit diagram in the fourth embodiment, and FIGS. 11 to 13 are timing charts of the recording operation in the fourth embodiment. In the figure, 1 is a laser printer main body, 2 is a photosensitive drum, 5 is a primary charging roller, 7 is a developing roller, 17 is a microprocessor, 18 is an interface circuit, 19 is a code storage memory, and 20 is image data storage. Memory.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toshio Yoshimoto 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Yoshimi Kuramochi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Incorporated (72) Inventor Shunichi Masuda 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (56) References JP-A-1-93362 (JP, A) JP-A-62-82768 (JP) JP-A-63-274550 (JP, A) JP-A-60-257262 (JP, A) JP-A-2-2049 (JP, A) JP-A-63-222864 (JP, A) (58) Surveyed field (Int.Cl. ⁶ , DB name) B41J 2/44 B41J 13/00 B41J 29/38 G03G 15/04

Claims (2)

(57) [Claims] A conversion means for converting information from a higher-level device into pixel information; and irrespective of whether or not the photosensitive member has been driven for recording the previous page, after receiving the information of one page, Before the conversion into the pixel information is completed, output means for outputting a signal to start feeding the recording medium, sheet feeding means for feeding the recording medium, and an image to be transferred to the fed recording medium are formed. Control means for controlling the drive of the photoconductor, wherein the control means outputs a signal to start feeding the recording medium when the photoconductor is driven for recording the previous page. In this case, while continuing to drive the photoconductor,
The recording medium is fed to a predetermined standby position, and when output is performed when the photoconductor is not driven, the driving of the photoconductor is started and the recording medium is fed to the standby position. Recording device. 2. The apparatus according to claim 1, wherein the controller stops driving the photoconductor when the standby state of the recording medium at the standby position continues for more than a predetermined time.
The recording device according to any one of the preceding claims.