JP2002019233A - Image forming apparatus, method of forming image, printer controller and printer engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of executing continuous duplication with a short waiting time period when a manuscript reading device is connected thereto. SOLUTION: When a print request is generated from a host computer 2104, a printer controller 2103 issues a printer mode command before issuing a printer start command. An engine control section 2002 that receives the command judges whether or not the printing is to be continuously performed upon the completion of the transferring of an image to a recording paper or whether or not the printing is to be finished and a post-processing is to be performed. When a print request is generated by pressing of a copy start key, the printer controller 2103 issues a copy mode command before issuing a print start command. The engine control section 2002 that receives the command judges whether or not the printing is to be continuously performed when a predetermined time period has passed after the transferring of an image to a recording paper is completed or whether or not the printing is to be finished and a post- processing is to be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image forming apparatus, an image forming method, a printer controller, and a printer engine.

[0002]

2. Description of the Related Art Conventionally, an image forming apparatus connected to a host computer or a network and used as a printing apparatus is known. Recently, it has been known that a document reading apparatus can be connected to be used as a copying apparatus without going through a host computer.

In this case, a host computer, a network, and a document reading device are connected to a printer controller. When image data is sent from the host computer, the printer controller confirms that the printer engine is in a ready state, and then sends a print request to the printer engine.

[0004] When the printer engine receives the print request, it starts a print preparation operation. When the print preparation is completed, the printer engine outputs a vertical synchronization signal to the printer controller. The printer controller transmits the image data sent from the host computer to the printer engine in synchronization with the vertical synchronization signal.

The printer engine can accept the next print request during the image formation (ready state). If the next print request is received before the image formation is completed, the printer engine stops driving. Without printing, the next image is printed continuously.

On the other hand, if the next print request is not received before the image formation is completed, the printer engine stops driving. When printing multiple pages of images continuously when the image forming apparatus is used as a printing apparatus, the next image data is already stored in the memory of the host computer or the printer controller even when the printer engine is forming an image. Since the printer engine is held, a print request can be issued immediately when the printer engine becomes ready.

For this reason, when the printer engine receives the next print request before the end of image formation, it does not stop driving, but continues to perform the next print, thereby completing printing of a predetermined number of sheets. The printing can be continuously performed without stopping the drive until the printing is completed. In this case, printing can be performed with the highest throughput that can be output by the printer engine.

[0008]

However, in a configuration in which the original reading device is directly connected to the printer controller and the copying operation is performed without the intervention of the host computer, the time required for the printer engine to perform image formation is reduced.
In many cases, the time required for the document reading device to read the document becomes long.

In general, after the reading of a document is completed, a predetermined time is required until the next document can be read. By this, even when continuous copying is required, the printer engine must wait until the image formation is completed.
The printer controller cannot prepare the next image data. That is, since the printer controller cannot transmit the next print request to the printer engine before the image formation is completed, the printer engine determines that there is no next image data and stops driving the engine.

Further, the printer controller sends a print request to the printer engine when the preparation for starting the next image transmission is completed. The printer engine starts driving after receiving the print request and starts printing. After the preparation operation is completed, a vertical synchronization signal is output to the printer controller. This does not pose a problem if the printer engine requires a short time to perform the printing preparation operation. However, a printer engine that requires cleaning inside the printer and warming up of the fixing device requires several seconds to several tens of seconds.

Therefore, when it is desired to copy a plurality of copies, or to copy a plurality of documents continuously using the automatic document feeder, the user must stop and start the printer engine every time a portion is copied. You will have to wait for the time to do it.

Accordingly, the present invention provides an image forming apparatus, an image forming method, and a printer controller which can perform continuous copying with a short waiting time without largely changing a control unit of a printer engine when a document reading apparatus is connected. And a printer engine.

[0013]

According to one aspect of the present invention, there is provided an image forming apparatus comprising: a printer engine; and a printer controller for controlling a driving state of the printer engine. In an image forming apparatus that forms an image input from an input device on a sheet, the printer controller continues forming the next image without stopping the driving of the printer engine based on the input performance of the image input device. Control instruction issuing means for issuing, to the printer engine, a control instruction that has determined a determination timing for determining whether to perform the determination. The printer engine varies the determination timing in accordance with a control instruction from the printer controller. Timing variable means for performing the above-mentioned printer control by the variable judgment timing. If the print start command over La was issued, characterized by continuing the formation of the image.

The printer engine forms an image by transferring an image formed on a photoreceptor to a recording sheet by electrophotography, and the image input device is a document reading device, and operates as a copying machine. In this case, when a predetermined time has elapsed from the end of the transfer, the determination timing is used. When the printer operates as a printer that prints image data transmitted from the host computer as the image input device, the transfer end time is used as the determination timing. Is preferred.

Further, when operating as a facsimile apparatus that prints image data input through a line connected to a communication device as the image input device, a predetermined time after the end of transfer may be set as the determination timing. preferable.

Preferably, the predetermined time is a time sufficient for the printer controller to issue a next print start command.

Further, the printer controller has one control command issued to the printer engine, and additional information in which the predetermined time is set is added to the control command. It is preferable that a predetermined time set in the information is read, and the determination timing is varied by the timing varying means.

According to a sixth aspect of the present invention, there is provided an image forming method, wherein an image input from an image input device is formed on a sheet using an image forming apparatus having a printer engine and a printer controller for controlling a driving state of the printer engine. In the image forming method, based on the input performance of the image input device, a control command that determines a determination timing for determining whether or not to continue formation of a next image without stopping driving of the printer engine. Issuing from the printer controller to the printer engine, varying the determination timing in accordance with a control command from the printer controller, and printing from the printer controller by the variable determination timing. If a start command has been issued, the Characterized by a step of continuing growth.

According to a seventh aspect of the present invention, there is provided a printer controller for issuing a print start command to a printer engine in order to form an image input from an image input device on a sheet, based on the input performance of the image input device. A control instruction issuing means for issuing to the printer engine a control instruction that determines a determination timing for determining whether to continue forming the next image without stopping the driving of the printer engine, The print start command is issued by the determination timing determined by the control command to cause the printer engine to continue forming the image.

According to another aspect of the present invention, there is provided a printer engine for forming an image input from an image input device on a sheet in accordance with a print start command issued from a printer controller, based on the input performance of the image input device. Receiving means for receiving, from the printer controller, a control command that determines a determination timing for determining whether to continue formation of the next image without stopping driving of the printer engine, and A timing varying means for varying the determination timing according to a command, wherein if the print start command has been issued from the printer controller before the variable determination timing, the image formation is continued. I do.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of an image forming apparatus, an image forming method, a printer controller and a printer engine according to the present invention will be described with reference to the drawings.

[First Embodiment] [Overall Configuration] FIG. 1 is a diagram showing a configuration of an image forming apparatus according to a first embodiment. In the figure, reference numeral 101 denotes a document reading device. Reference numeral 102 denotes a document table. 103 is a light source. Reference numeral 104 denotes a photoelectric conversion unit. 105 is an analog-to-digital converter.

Reference numeral 2001 denotes a printer main body. 2002
Reference numeral denotes a DC controller (engine control unit) that controls paper transport and image formation of the printer. Reference numeral 2003 denotes an image forming unit. Reference numeral 2103 denotes a PDL controller (printer controller), which is built in the printer body.

2104 is a one-to-one or network 2
The host computer is connected to the printer controller 2103 via the printer 105. Reference numeral 2004 denotes a paper cassette deck that can be added as an option. 2005
Is a sorter that can be added as an option. An optional controller 2006 controls the sheet cassette deck 2004 and the sorter 2005.

A printer controller 2103 is a digital image processing section for processing image data output from the analog-to-digital conversion section 105, a motor control section for controlling a motor for reading a document, and a communication control section with the engine control section 2002. And a communication control unit for performing

[Configuration of Printer Controller and Printer] First, the configurations of the printer controller 2103 and the printer 2102 will be described. FIG. 2 is a block diagram showing a configuration of an image forming apparatus connected to a host computer or a network. In the figure, reference numeral 2101 denotes a video I / F, which performs communication between the printer 2102 and the printer controller 2103. Details of each signal of the video I / F will be described later.

The printer 2102 has a video I / F 2101.
An image is formed on the basis of image data input through the printer, and various loads are controlled in order to perform an image forming sequence in which the image is transferred and fixed on a recording sheet and then output. In addition, the status of the printer is detected and the printer controller 2103
Notify.

The printer controller 2103 includes an analog-to-digital converter 105 and a host computer 2104.
Alternatively, it receives data transmitted via the network 2105. This data is bitmap data, P
DL (Page Description Langu)
age) It is sent in various formats such as description data.

The printer controller 2103 develops the transmitted data in a memory and transfers the data to the printer 2102 as raster data. Data read from the manuscript or host computer 2104
Can be output by the printer 2102.

Next, a video I / F 2101 for connecting the printer controller 2103 and the printer 2102 will be described. FIG. 3 is a diagram showing a configuration of the video I / F 2101. In the figure, as described above, reference numeral 2103 denotes a printer controller, and reference numeral 2002 denotes an engine control unit (DC controller) that performs engine control of the printer 2102. Various signal lines are connected between the printer controller 2103 and the engine control unit 2002 to exchange signals.

FIG. 4 is a table showing a list of video I / F signals. Here, only the representative signals shown in FIG. 3 are shown. The printer power ready (/ PPRDY) signal is supplied from the power supply to the printer 2102, and after the processing such as the initial setting is completed, the printer controller 210
3 is a signal indicating that communication with the C.3 is enabled.

Controller power ready (/ CPRD)
Y) The signal 204 is a signal indicating that power has been supplied from the power supply to the printer controller 2103 and communication with the engine control unit 2002 has been enabled after processing such as initialization has been completed.

Top of page (/ TOP) signal 207
Is a synchronization signal passed from the engine control unit 2002 to the printer controller 2103 and serving as a reference for vertical scanning of an image. This / TOP signal 207 is a signal / PR
After the INT signal 206 is output from the printer controller 2103, it is output after a predetermined time has elapsed. Specifically, engine control unit 2002 outputs / PRNT signal 206
After receiving the command, pre-processing such as the start of driving of each control load, cleaning of the inside of the printer, and warming up of the fixing device is performed.
07 is output.

Line synchronization (/ LSYNC) signal 208
Is a synchronization signal which is used as a reference for horizontal scanning by the printer controller 2103. Like the / TOP signal 207, /
After the PRNT signal 206 is output from the printer controller 2103, it is output to the printer controller 2103 after a predetermined time has elapsed.

Video clock (/ VCLK) signal 209
Is a synchronous clock for the image enable (/ VDOEN) signal and the image (/ VDO) signal, and generates a clock having a frequency corresponding to the image signal from the printer controller 2103.

Image enable (/ VDOEN) signal 21
0 is a signal for controlling the capture of the image signal output from the printer controller 2103 into the engine control unit 2002. The engine control unit 2002 synchronizes with the video clock (/ VCLK) signal, and the / VCLK signal
RUE (true) / FALSE (false)
In the case of RUE, the image signal is captured, and in the case of FALSE, the capture is not performed.

The image (/ VDO) signal 211 is image data. The printer controller 2103 outputs the / TOP signal 207 in the vertical direction and / LSY in the horizontal direction.
The signal is output in synchronization with the / VCLK signal 209 based on the NC signal 208.

A controller clock (/ CCLK) signal 212 is a synchronous clock used when the printer controller 2103 transmits a serial command to the engine controller 2002 and when the engine controller 2002 returns a serial status to the printer controller 2103. Are output from the printer controller 2103.

Command busy (/ CBSY) signal 213
Is the command (/ CM)
D) A signal indicating to the engine control unit 2002 that the serial command is transmitted using the signal.

A command (/ CMD) signal 214 is a signal used when the printer controller 2103 transmits serial information to the engine control unit 2002.
Here, the serial information is called a command.

Status busy (/ SBSY) signal 21
5 is a status (/ ST)
S) This signal indicates to the printer controller 2103 that the serial status is returned using the signal.

The status (/ STS) signal 216 is sent to the printer controller 2103 by the engine control unit 2002.
This signal is used when replying serial information to. Here, the serial information is called a status.

State change notification (/ CCRT) signal 217
Is a signal for reporting to the printer controller 2103 when the status inside the printer has changed. Upon receiving the / CCRT signal, the printer controller 2103 issues a command for inquiring about what has changed in the state of the engine using the command (/ CMD) signal 214, and the engine control unit 2002 responds to the status (/ (STS) signal 216 informs the state.

[Configuration of Printer] Engine control unit 200
2 shows a configuration of a printer engine 2102 controlled by the printer engine 2. FIG. 5 is a diagram showing a configuration of the printer engine. In the figure, reference numeral 113 denotes a scanner, which is an image signal (/ VDD) sent from the printer controller 2103.
O) After receiving the 211 and converting it into a laser beam, it irradiates the photoconductor 108 to form an electrostatic latent image on the photoconductor 108.

The electrostatic latent image formed on the photosensitive member 108 is
It reaches the developing device 123 while rotating clockwise. The developing device 123 places (develops) the toner on the photoconductor 108 according to the electric charge charged on the photoconductor 108.

On the other hand, the pickup rollers 132a, 132
The recording paper fed in b is fed by paper feed rollers 134a, 134
b, and is conveyed to the position before the cash register.

The recording paper is controlled so that the leading end of the image developed on the photosensitive member reaches the nip portion at the timing when the leading end reaches the nip portion with the transfer roller 120. When the recording paper arrives, the photoconductor 108 comes into contact with the recording paper and the toner is transferred to the recording paper. The image transferred to the recording paper is fixed on the recording paper by heat and pressure in the fixing device 121.

The recording paper on which the image has been fixed is conveyed to the face-down discharge port 122 and discharged. This allows
The image information sent from the printer controller 2103 can be output.

[Timing Chart of Image Signal] FIG. 6 is a timing chart showing changes in signals exchanged in the video I / F 2101. First, when the preparation of image information by the printer controller 2103 is completed, a print start command is transmitted using the command (/ CMD) signal 214 and transmitted to the engine control unit 2002. At the same time, an image synchronizing signal (/ V
CLK signal) 209 is generated.

In response, the engine control unit 2002
Performs various settings inside the printer, and when the image can be received, the / TOP signal 207 and the LSYNC signal 208 are transmitted to the printer controller 210.
Output to 3.

In accordance with the vertical synchronizing signal (/ TOP signal) and the horizontal synchronizing signal (/ LSYNC signal), the printer controller 2103 converts the image signal (/ VDO signal) and the / VDOEN signal which is an image valid signal into an engine controller. 2
002.

Next, commands and statuses exchanged by serial communication during the printing operation are shown. FIG. 7 is a timing chart showing serial communication between the printer controller 2103 and the engine control unit 2002.

The case where the state change notification signal (/ CCRT signal) is not used is shown. When the printer controller 2103 issues a command to the engine control unit 2002, the command busy (/ CBSY) signal is set to L level (true),
In synchronization with the clock (/ CCLK) signal, the command (/
CMD) signal to send command data.

The engine control unit 2002 receiving this message
After confirming that the command busy (/ CBSY) signal is at the H level (false), the status busy (/
SBSY) signal to L level (true), and the controller clock (//
The status (/ STS) is sent to the printer controller 2103 in synchronization with the (CCLK) signal. The print controller 2103 receives this status data, and print control is continued or interrupted depending on the state.

Subsequently, the state change notification signal (/ CCRT)
Signal). This signal is an L level (true) signal when the state of the printer engine specified by the printer controller 2103 changes in advance. For example, when the absence of paper occurs, the state change notification signal (/ CC
It is assumed that the printer controller 2103 has previously set a command (/ CMD) signal so as to enable the (RT signal).

When there is only one remaining recording sheet and the printer controller 2103 issues a printout request for two sheets, the print sequence operation for the first sheet is normally processed without any problem. However, since the second recording sheet does not exist, at the stage when the second image formation is started, the printer engine detects the state change and changes the / CCRT signal from H level to L level. .

This / CCRT signal is transmitted to the printer controller 2103. Printer controller 210
3 detects this and immediately starts the engine control unit 2002
In order to know which paper cassette is out of paper, a command requesting a paper feed unit presence / absence status is issued. In response to this request command, the engine control unit 2002 returns the status of the paperless cassette to the printer controller. The / CCRT signal is cleared to the H level at the timing when the status busy (/ SBSY) signal for returning the status goes to the L level.

Specifically, the printer controller 2103
7 shows a print operation according to the exchange of a command / status of the engine control unit 2002. FIG. 8 is a diagram showing serial communication during a printing operation. This serial communication is for color output. When a print start request is generated, the printer controller 2103 checks the ready state of the printer with the engine control unit 2002 while performing conversion processing of image data and the like. Issue a command to specify the paper feed tray for recording paper. Further, a command for requesting the size of the recording paper in the designated paper feed tray (cassette) is issued. In response to these series of commands, the engine control unit 2002 returns a corresponding status.

Thereafter, the printer controller 2103
Issues a print start command to the engine control unit 2002. In response to this, the engine control unit 2002 returns a / TOP signal after a predetermined time has elapsed.
The vertical scanning direction is synchronized with this / TOP signal.
While synchronizing the horizontal scanning direction with the / LSYNC signal, the image (/ VDO) signal is transferred to the engine control unit 2002 in synchronization with the video clock (/ VCLK).

Then, if a print request for the next page has occurred after the generation of the TOP signal, a print start command is issued again. Normally, when the next print start command has not been issued when the transfer of the image formed on the photoconductor 108 onto the recording paper is completed, the engine control unit 2
002 detects that the print request has been completed, and shifts to post-processing such as a cleaning operation of the transfer roller 120. Further, the transferred recording paper passes through the fixing device 121 and is then discharged to a designated paper discharge port. Finally, the printer controller 2103 confirms to the engine control unit 2002 that the recording sheet is not in the transporting state (end of paper discharge),
Printing is completed, and the printer waits for a ready state until the next print request is issued.

When an illegal (irregular) state such as a jam of the recording paper, no recording paper, or opening of the door by the user occurs during such an operation, the engine control unit 2002 immediately uses the / CCRT signal to detect a printer abnormality. To the printer controller 2103. The printer controller 2103 performs this processing.

The processing described above is performed by the printer controller 2
This is a process performed between the control unit 103 and the engine control unit 2002.

FIG. 9 is a diagram showing the configuration of an image forming apparatus as a printer. In the figure, as described above, 200
Reference numeral 1 denotes a printer main body. Reference numeral 2002 denotes a DC controller (engine control unit) that controls paper transport and image formation of the printer. Reference numeral 2003 denotes an image forming unit. 210
Reference numeral 3 denotes a printer controller.
1 is built in.

Reference numeral 2104 denotes a host computer connected to the printer controller 2103 via one-to-one or a network 2105. Reference numeral 2004 denotes a paper cassette deck that can be added as an option. 2
005 is a sorter that can be added as an option. 200
6 is a paper cassette deck 2004 and a sorter 2005
Is an optional controller that controls

[Operation as Printer] One-to-one or printer controller 2 via network 2105
When a print request is issued from the host computer 2104 connected to the image forming apparatus 103, the image forming apparatus operates as a printer.

In this case, the next image data to be printed during the image forming operation by the printer is stored in the host computer 210.
4 or already stored in the memory of the printer controller 2103, and / TO
After the output of the P signal, as shown in FIG. 10, it is sufficiently possible to issue a print start command until the transfer of the image to the recording paper is completed. That is, it is appropriate to determine whether or not the printing is completed at the time when the transfer of the image to the recording paper is completed. FIG. 10 is a timing chart showing changes in various signals when a print start command is issued before the end of transfer.

[Operation as Copying Machine] FIG. 11 is a diagram showing a configuration of an image forming apparatus as a copying machine to which a document reading device and a document feeding device are connected. When the copy start key of the operation unit (not shown) on the document reading apparatus is pressed and a print request is issued, the image forming apparatus operates as a copying machine.

In this case, the printer controller 2103
After the original is fed onto the platen by the original feeder 801,
The image data read from the document by operating the optical reading device 802 is developed on the memory. As soon as the image data is ready, a print start command is issued, and the image is formed by operating in the same manner as when operating as a printer.

When the copying operation is performed continuously, after the reading operation, the next document is fed onto the document table by the document feeding device 801 and at the same time, the optical reading device 802 is returned to the reading start position, and then the next document is read. After the original is read and the image data is ready, the next print start command is issued.

If the time required for these operations is long, the engine control unit 2002 does not end these operations until it determines that printing has been completed.
In step 002, it is determined that printing is completed. FIG. 12 is a timing chart showing changes in various signals when a print start command is issued after transfer is completed. In this case, after the post-processing is performed and the driving is stopped, the printer is started again, the pre-processing is performed, and then the image is formed, and the throughput is reduced.

In order to solve such a problem, in this embodiment, two types of timings for judging the end of printing are prepared. That is, when operating as a printer, the end of the transfer of the recording paper is used as the determination timing. After that time) is the timing of the determination.

In order to use two types of judgment timings, two types of commands for instructing the engine control unit 2002 are prepared. That is, a printer mode command requesting that the end of the transfer be the timing of the determination,
This is a copy mode command requesting that a certain time after the end of the transfer be determined.

When a print request is issued from the host computer 2104, the printer controller 2103 issues a printer mode command before issuing a printer start command. After receiving the printer mode command, the engine control unit 2002 determines whether to continue printing when the transfer of the image from the intermediate transfer body to the recording paper is completed or to end printing and shift to post-processing. to decide.

On the other hand, if the print request is generated by pressing the copy start key of the operation unit, a copy mode command is issued before issuing the print start command.
Engine control unit 200 that has received the copy mode command
Step 2 is for determining whether to continue printing after a lapse of a predetermined time after the transfer of the image from the intermediate transfer body to the recording paper is completed, or to terminate printing and shift to post-processing. I will be.

[Second Embodiment] The image forming apparatus according to the second embodiment is obtained by adding a facsimile function to the function of the image forming apparatus according to the first embodiment. The basic configuration is the same as that of the first embodiment, and a description thereof will be omitted.

In the second embodiment, a modem for facsimile (FAX) data transmission / reception is connected to the printer controller. When FAX data is received from the modem, a print request is issued, as in the case of transmitting image data from the host computer 2104 or pressing the copy start key of the operation unit.

Although it depends on the performance of the modem, the state of avoidance, and the performance of the other party's facsimile machine, it generally takes several seconds to several tens of seconds to receive one page of FAX data. That is, when FAX data including a plurality of pages is received, the next image data may not be ready before the image of the first page is completely transferred to the recording paper.

Therefore, similarly to the operation of the copying machine of the first embodiment, it is necessary to change the timing for determining whether to continue printing or to end printing and shift to post-processing. . For this reason, in the second embodiment, in addition to the printer mode and the copy mode,
The judgment timing in the mode is prepared.

That is, when operating as a facsimile machine, the timing of the determination after the elapse of a fixed time (time sufficient for the printer controller 2103 to receive the next FAX data and issue a print start command) from the end of the transfer is determined. I do. Further, a FAX mode command for switching to the timing of the FAX mode determination is prepared.

As in the first embodiment, when a print request is generated due to the reception of FAX data, the FAX is issued prior to issuing a print start command.
Issue a mode command.

After receiving the FAX mode command, the engine control unit 2002 continues printing or terminates printing at a certain time after the transfer of the image from the intermediate transfer body to the recording paper has been completed. Then, it is determined whether to shift to post-processing.

[Third Embodiment] The basic configuration of an image forming apparatus according to the third embodiment is the same as that of the first and second embodiments, and a description thereof will be omitted. In the first and second embodiments, timings for making a determination to shift to post-processing are prepared in accordance with factors (such as image input performance) that caused a print request, and commands corresponding to the respective timings are prepared. I was

On the other hand, in the third embodiment, only one command for changing the timing for making a decision to shift to post-processing is prepared, and the time from the end of the image transfer to the recording paper is set as additional information. Included. Upon receiving this command, the engine control unit 2002 reads the supplementary information, and performs continuous printing when the time set in the supplementary information has elapsed since the end of the image transfer to the recording paper, or
Alternatively, it is determined whether to end printing and shift to post-processing.

As described above, the printer controller 210
No. 3 issues a command by calculating a time for delaying the timing of the determination depending on the factor that generated the print request.

Although the embodiments of the present invention have been described above, the present invention is not limited to the configurations of these embodiments, and the functions described in the claims or the functions of the embodiments are described. Any configuration that can achieve the function of the configuration is applicable.

For example, a communication device connected to a network line for inputting image data may be provided inside the image forming apparatus or may be provided outside.

In the above embodiment, the case where an image is formed by an electrophotographic method has been described. However, a printing method such as an ink jet method, a dot impact method, a thermal transfer method, and a bubble jet (registered trademark) method is not particularly limited.

[0088]

According to the present invention, the throughput of the image forming apparatus can be optimized according to the capability (performance) of the connected image input apparatus. Thus, when a document reading apparatus is connected, continuous copying with a short waiting time can be performed without largely changing the control unit of the printer engine.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of an image forming apparatus according to a first embodiment.

FIG. 2 is a block diagram illustrating a configuration of an image forming apparatus connected to a host computer or a network.

FIG. 3 is a diagram illustrating a configuration of a video I / F 2101.

FIG. 4 is a table showing a list of video I / F signals.

FIG. 5 is a diagram illustrating a configuration of a printer engine.

FIG. 6 is a timing chart showing changes in signals exchanged in the video I / F 2101.

FIG. 7 is a timing chart showing serial communication between the printer controller 2103 and the engine control unit 2002.

FIG. 8 is a diagram illustrating serial communication during a printing operation.

FIG. 9 is a diagram illustrating a configuration of an image forming apparatus as a printer.

FIG. 10 is a timing chart showing changes in various signals when a print start command is issued before the end of transfer.

FIG. 11 is a diagram illustrating a configuration of an image forming apparatus as a copying machine to which a document reading device and a document feeding device are connected.

FIG. 12 is a timing chart showing changes in various signals when a print start command is issued after transfer is completed.

[Explanation of symbols]

 101 Document Scanner 2002 Engine Control Unit 2102 Printer Engine 2103 Printer Controller 2104 Host Computer

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 2C061 AP01 AP03 AP04 AQ01 AQ04 AQ05 AQ06 HJ10 HK19 HT03 HV09 HV10 HV13 2H027 DA33 DA39 EE02 EE04 EF11 EF13 EH08 FA08 FA25 ZA07 5C062 AA35 AB17 AB AC02 AC04 AC13 AC68 AC69 AE15 BA02 BA04

Claims (8)

[Claims] 1. An image forming apparatus comprising: a printer engine; and a printer controller for controlling a driving state of the printer engine, wherein the image controller forms an image input from an image input device on a sheet. Based on the input performance, a control instruction that issues a control instruction to the printer engine that determines a determination timing for determining whether to continue formation of the next image without stopping driving of the printer engine is issued. The printer engine includes a timing varying unit that varies the determination timing in accordance with a control command from the printer controller, and a print start command has been issued from the printer controller before the variable determination timing. In this case, the formation of the image may be continued. An image forming apparatus comprising. 2. The printer engine forms an image by transferring an image formed on a photoreceptor to recording paper by an electrophotographic method, wherein the image input device is a document reading device, and operates as a copying machine. In this case, when the predetermined time has elapsed since the end of the transfer, the determination timing is used. When the printer operates as a printer that prints image data transmitted from the host computer as the image input device, the transfer end time is used as the determination timing. The image forming apparatus according to claim 1, wherein: 3. When operating as a facsimile apparatus that prints image data input through a line connected to a communication device as the image input device, it is preferable that the determination timing be a predetermined time after the end of transfer. The image forming apparatus according to claim 2, wherein: 4. The image forming apparatus according to claim 1, wherein the predetermined time is a time sufficient for the printer controller to issue a next print start command. 5. A control command issued from the printer controller to the printer engine, and additional information in which the predetermined time is set is added to the control command. 2. The image forming apparatus according to claim 1, wherein a predetermined time set in the information is read out, and the determination timing is changed by the timing changing unit. 6. An image forming method for forming an image input from an image input device on a sheet using an image forming device including a printer engine and a printer controller for controlling a driving state of the printer engine, the image input device comprising: Based on the input performance of the printer engine, the printer controller issues a control command that determines a determination timing for determining whether to continue forming the next image without stopping the driving of the printer engine from the printer controller to the printer engine. Issuing, in the printer engine, varying the determination timing in accordance with a control command from the printer controller; and if a print start command has been issued from the printer controller by the variable determination timing,
Continuing the formation of the image. 7. A printer controller for issuing a print start command to a printer engine in order to form an image input from an image input device on a sheet, wherein the printer engine is driven based on input performance of the image input device. A control command issuing unit that issues a control command to the printer engine to determine a determination timing for determining whether or not to continue forming the next image without stopping, the control command being issued to the printer engine; A printer controller which issues the print start command by a determination timing to cause the printer engine to continue forming the image. 8. A printer engine for forming an image input from an image input device on a sheet according to a print start command issued from a printer controller, wherein the driving of the printer engine is performed based on input performance of the image input device. Receiving means for receiving, from the printer controller, a control command for determining a determination timing for determining whether or not to continue formation of the next image without stopping; and determining the determination timing in accordance with the received control command. A printer engine, comprising: a variable timing variable unit, wherein the printer engine continues to form the image if the print start command has been issued from the printer controller before the variable determination timing.