JP2008062580A - Image forming apparatus and its controlling method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide both maintenance of a machine state by adjustment processing and reduction of a downtime a user feels, by performing in parallel development processing and adjustment processing of PDL data or the like. <P>SOLUTION: The image forming apparatus includes, for example: a development section for developing data such as PDL data to form an image; and an adjustment section for performing adjustment processing to properly maintain a machine state for quality or the like of an image to be formed in parallel with development of the data. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an image forming apparatus, and more particularly to a technique for reducing downtime due to adjustment processing.

  Conventionally, an image forming apparatus such as a multifunction printer has been mainly a monochrome machine, but in recent years, an image forming apparatus having a full-color print function has been increasing.

  As the image forming apparatus continues to be used, the state of the fuselage changes. As a result, the image quality and functions are lower than originally intended. In particular, in a full-color image forming apparatus, adjustment processing for maintaining image quality is required.

  However, it is a burden for the user to execute an adjustment operation that requires knowledge about the image forming apparatus based on the user's judgment. Therefore, it is desirable that the image forming apparatus is equipped with a function (automatic adjustment function) that automatically executes adjustment processing.

Examples of the adjustment processing include auto registration for adjusting color misregistration, automatic density adjustment for maintaining gradation characteristics, and automatic toner supply amount adjustment. For these, the execution timing is determined based on the cumulative number of prints, the cumulative number of pixels of the image data (video count), etc., and the adjustment process is automatically executed. Thereby, even if a user does not care about the state of an airframe, there exists an advantage that an airframe is automatically maintained in the suitable state (patent document 1).
JP 2004-125986 A

  Conventionally, however, the adjustment process may be executed while the user is executing printing or when the user is about to execute printing. Since the image formation is interrupted during the period during which the adjustment process is being performed (downtime), the user has to wait until the adjustment process is completed.

  By the way, the image forming apparatus may receive print data from an external PC, develop it into a raster image, and execute image formation. In recent years, image formation target data has become complicated, and it may take several seconds to several minutes from when print data is received until its development is completed. Of course, the deployment time at this time is also downtime.

  As described above, when the adjustment processing execution timing is reached during the development of the print data, the downtime becomes a time obtained by adding the adjustment processing time in addition to the development time, and the user waits longer than usual. . This has been one of the complaints of users.

  In view of the above, an object of the present invention is to achieve both maintenance of the body state (particularly, the body state relating to image quality) by adjustment processing and reduction of downtime experienced by the user.

  The image forming apparatus of the present invention executes, for example, a developing unit that develops data such as PDL data for forming an image, and an adjustment process for suitably maintaining the state of the machine body in parallel with the data development. And an adjusting unit.

  According to the present invention, it is possible to achieve both maintenance of the aircraft state by the adjustment processing and reduction of downtime experienced by the user by executing the expansion processing of PDL data and the adjustment processing in parallel. Become.

  An embodiment of the present invention is shown below. Of course, the individual embodiments described below will be helpful in understanding various concepts such as the superordinate concept, intermediate concept and subordinate concept of the present invention. Further, the technical scope of the present invention is determined by the scope of the claims, and is not limited by the following individual embodiments.

  FIG. 1 is an exemplary schematic cross-sectional view of an image forming apparatus according to an embodiment. The image forming apparatus is realized as a printing apparatus, a copying machine, a printer, a facsimile machine, or a multifunction machine (MFP).

  The printer engine 101 includes various hardware mechanisms for forming an image. The controller 103 is a control unit for controlling the entire image forming apparatus. The engine control unit 104 is a control unit that causes the printer engine 101 to perform image formation in accordance with a control command and image data received from the controller 103. Further, the engine control unit 104 may notify the controller 103 of conditions for executing adjustment processing (sometimes referred to as automatic adjustment), the state of the printer engine 101, and the like.

  As is well known, each of the image forming units 105, 106, 107, and 108 includes a photosensitive drum, a primary charger, a laser exposure device, a developing sleeve, a drum cleaner, and the like. Each image forming unit executes image forming of each color of Y, M, C, and K and primary transfer to the intermediate transfer belt (ITB) 109.

  On the surface of the intermediate transfer belt 109, developer images of respective colors are sequentially superimposed by the image forming units 105 to 108, and finally one color image is formed. The intermediate transfer belt 109 rotates clockwise in FIG. The pattern detection sensor 113 detects a test pattern for adjustment processing (eg, auto registration, density adjustment, etc.). The pattern detection sensor 113 is arranged downstream of the image forming unit as shown in FIG.

  The secondary transfer roller 114 secondarily transfers the color image on the intermediate transfer belt 109 onto the recording medium. The belt cleaner 115 cleans the intermediate transfer belt 109 after the secondary transfer.

  The recording medium fed from the paper feeding units 131 and 132 and the manual feed tray 137 is conveyed by the pre-registration roller 116, and when the leading edge is detected by the registration sensor 117, the recording medium is temporarily stopped so as to abut against the registration roller 118. The Thereafter, the recording medium is conveyed by the registration roller 118 and the pre-registration roller 116 in synchronization with the timing at which the image on the intermediate transfer belt 109 arrives at the secondary transfer position. Then, the color image on the intermediate transfer belt 109 is secondarily transferred to the recording medium by the secondary transfer roller 114. The secondary transfer conveyance belt 119 conveys the recording medium after the secondary transfer to the fixing device 120. The fixing device 120 fixes an unfixed color image on a recording medium.

  The recording medium loaded in the paper feed cassettes 128 and 129 is fed toward the vertical pass rollers 135 and 136 by paper feed units 131 and 132 such as pickup rollers. The fed recording medium is conveyed to the pre-registration roller 116 described above by the vertical pass rollers 135 and 136.

  FIG. 2 is an exemplary block diagram of a control unit according to the embodiment. The CPU 230 is a central control unit in the controller 103. The ROM 231 is a storage unit that stores a control program of the controller 103 and the like. The RAM 232 is a storage unit used as a work area when the CPU 230 executes a control program. The nonvolatile memory 233 is a storage unit for storing various adjustment values.

  The network I / F 236 is a communication unit that receives print data such as PDL data transmitted by the host PC. When the CPU 230 receives a command transmitted from the host PC or another image forming apparatus via the network I / F 236, the CPU 230 stores the command in the RAM 232 as needed.

  The data storage 237 is a storage unit that temporarily stores received PDL data strings. A RIP (raster image processor) unit 238 is a unit that rasterizes the PDL data of each page and creates printable image data. In FIG. 2, the RIP unit 238 and the CPU 230 are illustrated as separate blocks, but these may be realized by a single CPU. In this case, the CPU may execute control of the entire controller 103 and RIP deployment work in parallel by multitask processing.

  The image memory 239 is a storage unit that stores the image data output from the RIP unit 238. The engine I / F unit 240 is a communication unit that executes transmission / reception of commands with the engine control unit 104 and transfer of image data to the engine control unit 104.

  The CPU 210 is a central control unit of the printer engine 101. Reference numeral 211 denotes a ROM, which is a storage unit that stores a control program for the printer engine 101. The RAM 212 is a storage unit used as a work area when controlling the printer engine 101. The nonvolatile memory 213 is a storage unit that stores various adjustment values. The controller I / F 215 is a communication unit that transmits and receives commands with the controller 103 and receives image data from the controller 103. As described above, the image forming units 105 to 108 perform image formation using the image data that has passed through the controller I / F 215.

  The VSYNC generation unit 214 generates an image synchronization signal VSYNC and transmits it to the controller 103 via the controller I / F 215. The controller 103 transfers the image data to the engine control unit 104 in synchronization with VSYNC. As a result, the printer engine 101 and the controller 103 are synchronized.

  The adjustment unit 209 is a control unit for executing various adjustment processes for maintaining the image quality. For example, with regard to auto registration, the adjustment unit 209 reduces the occurrence of color misregistration by adjusting the relationship between VSYNC and image data in accordance with a signal detected by the pattern detection sensor 113 and an instruction from the CPU 210. Test pattern generators 217 to 220 generate and send test pattern image data used for adjustment processing to each image forming unit.

  The ITB control unit 221 executes drive control of the intermediate transfer belt 109. The fixing device controller 222 executes driving of the fixing device 120 and temperature adjustment. The drive system controller 223 controls each motor and solenoid in order to carry the recording medium and perform secondary transfer.

  Here, with reference to FIG. 3 to FIG. 5, a procedure for performing adjustment processing when data is received from the external host PC according to the present embodiment and a print job is executed will be described.

  FIG. 3 is a diagram illustrating an example of a management table of exemplary adjustment process items according to the embodiment. The management table is stored in the ROM 211, for example. Reference numeral 301 denotes a storage area for storing the type of adjustment process (adjustment process item). Reference numeral 302 denotes a storage area for storing execution conditions (number of sheets, etc.) of adjustment processing. Reference numeral 303 denotes a storage area for storing an execution time necessary for executing the corresponding adjustment process. Reference numeral 304 stores forcing conditions for forcibly executing the adjustment processing. The compulsory condition is, for example, the number of times the adjustment process is interrupted (interruption count).

  FIG. 4 is a flowchart of processing executed by the controller 103 in the control method according to the embodiment.

  In step S <b> 401, the CPU 230 transmits a print preparation request command to the engine control unit 104 via the engine I / F 240. In step S <b> 402, the CPU 230 receives print data such as PDL data through the network I / F 236 and stores it in the data storage 237.

  In step S <b> 403, the CPU 230 transmits a paper feed start request command to the engine control unit 104. In step S404, the CPU 230 starts the expansion process by transferring the stored print data to the RIP unit 238.

  In step S405, the CPU 230 determines whether or not the data expansion has been completed. When completed, the process proceeds to step S406, and the CPU 230 transmits a print start request command to the engine control unit 104. As can be seen from this flowchart, the print start request command implies the completion of data expansion. That is, when the CPU 210 of the engine control unit 104 receives the print start request command, it can recognize that the data expansion has been completed. In the present embodiment, the adjustment unit 209 of the engine control unit 104 executes the adjustment process in parallel with the RIP unit 238 executing the expansion process.

  In step S407, the CPU 230 determines whether print data for the next page remains. If the print data for the next page remains, the process returns to step S402 to receive and develop this print data. On the other hand, when there is no print data to be developed, the process proceeds to step S408, and the CPU 230 transmits an operation end request command to the engine control unit 104.

  FIG. 5 is a flowchart of processing executed in the engine control unit 104 in the control method according to the embodiment.

  In step S <b> 501, the CPU 210 determines whether a print preparation request has been received from the controller 103. When the print preparation request is received, the process proceeds to step S502, and the CPU 210 starts print preparation processing. Examples of the print preparation process include the start of rotation of a polygon mirror drive motor and a photosensitive drum included in the image forming unit. More specifically, the CPU 210 instructs the image forming unit 105, the ITB control unit 221, the fixing device control unit 222, and the drive system control unit 223 to prepare for printing.

  In step S <b> 503, the CPU 210 determines whether a paper feed start request is received from the controller 103. When the paper feed start request is received, the process proceeds to step S504, and the CPU 210 sends an instruction to the drive system controller 223 to drive the paper feed unit 131. When the registration sensor 117 detects the leading edge of the recording medium that has been conveyed, the CPU 210 instructs the drive system control unit 223 to stop the recording medium so that the recording medium comes into contact with the registration roller 118 and stops.

  Thereafter, the RIP unit 238 of the controller 103 waits for completion of data expansion, but the engine control unit 104 executes adjustment processing in parallel with data expansion by the RIP unit 238 as necessary. .

  In step S505, the CPU 210 reads out the number of interruptions managed for each adjustment processing item from the nonvolatile memory 213 and reads the compulsory condition (threshold number of interruptions) stored in the ROM 211. The number of interruptions exceeds the threshold value. It is determined whether or not. The number of interruptions is incremented by one when the adjustment process is started because the adjustment process is started in parallel with the data expansion but the data expansion is completed before the adjustment process is completed.

  If the number of interruptions exceeds the threshold, the process proceeds to step S506. In step S506, the CPU 210 immediately starts the adjustment process. In this case, image formation is temporarily interrupted as in the prior art. As described above, the CPU 210 functions as a unit that manages the number of times the adjustment process is interrupted and forcibly executes the adjustment process during or after image formation when the number of interruptions exceeds the threshold.

  When the adjustment process is completed, the process advances to step S512, and the CPU 210 determines whether a print start request has been received. When the print start request is received, the process proceeds to step S513, and the CPU 210 controls each unit to form an image based on the developed data. Thereafter, in step S514, the CPU 210 determines whether or not an operation end request has been received from the controller 103. When the CPU 210 receives the operation end request, the CPU 210 ends the series of processes. On the other hand, if not received, the process returns to step S503.

  If it is determined in step S505 that there is no adjustment processing item whose number of interruptions exceeds the threshold, the process proceeds to step S507. In step S507, the CPU 210 determines whether there is an adjustment process that satisfies the execution condition. For example, the CPU 210 reads the execution condition (threshold value) for each adjustment process from the management table (FIG. 3), and reads the count value of the number of interruptions corresponding to the adjustment process from the nonvolatile memory 213. Then, the CPU 210 determines whether or not the count value exceeds the threshold value. If there is no adjustment process that satisfies the execution condition, the process proceeds to step S512 described above.

  If there is an adjustment process that satisfies the execution condition, the process advances to step S508, and the CPU 210 instructs the adjustment unit 209 to start the adjustment process. For example, if the execution condition for auto registration is satisfied, the adjustment unit 209 instructs the test pattern generation units 217 to 220 to generate a test pattern. The test pattern is formed as a developer image on the intermediate transfer belt 109 by the corresponding image forming unit, and is detected by the pattern detection sensor 113. The adjustment unit 209 adjusts the image formation position based on the detection result.

  In step S <b> 509, the CPU 210 determines whether a print start request is received from the controller 103. If not received, the process proceeds to step S511, and the CPU 210 determines whether or not a report indicating that the adjustment process has been completed is received from the adjustment unit 209. If the adjustment process has been completed, the process proceeds to step S512. On the other hand, if the adjustment process has not ended, the process returns to step S509, and the adjustment unit 209 continues to execute the adjustment process.

  The fact that the print start request has been received before the adjustment process is completed means that the data development process has been completed before the adjustment process is completed. Accordingly, the process proceeds to step S510, and the CPU 210 sends an instruction to the adjustment unit 209 to interrupt the adjustment process that is currently being executed. The adjustment unit 209 interrupts the adjustment process according to this instruction. In addition, as part of the interrupt count management process, the CPU 210 increments the interrupt count corresponding to the interrupted adjustment process by one, and stores this in the nonvolatile memory 213. Thereafter, the process proceeds to step S513.

  According to the present embodiment, the development process of PDL data and the adjustment process are executed in parallel, thereby maintaining the machine state (particularly image quality) by the adjustment process and reducing the downtime experienced by the user. It is possible to achieve both.

  However, if the data development is completed before the adjustment process is completed, or if a request (for example, a print start request command) regarding the start of image formation on the recording medium is received during the adjustment process, The adjustment process is interrupted. As described above, when the execution time of the expansion process is shorter than the execution time of the adjustment process, the downtime felt by the user can be reduced by interrupting the adjustment process.

  On the other hand, if the number of interruptions exceeds the threshold value, an inadvertent decrease in the aircraft state (particularly image quality) is suppressed by forcibly executing the adjustment process.

[Other Embodiments]
Although FIG. 3 shows the execution time 303 necessary for executing each adjustment process, it is not always essential in the above-described embodiment. Of course, from the relationship between the execution time and the development time, it may be determined whether or not the adjustment process and the development process are executed in parallel.

  The CPU 230 or the RIP unit 238 of the controller 103 estimates the development time necessary for data development based on the amount of data and transmits the estimated development time to the engine control unit 104. Further, the ROM 211 of the engine control unit 104 stores an execution time (303 in FIG. 3) necessary for executing each of a plurality of adjustment processes.

  The CPU 210 of the controller 103 reads the execution time for the adjustment process that needs to be executed, and compares the read execution time with the estimated development time. When the development time is longer than the execution time, the CPU 210 instructs the adjustment unit 209 to execute an adjustment process for suitably maintaining the machine state in parallel with the development of the print data.

  As described above, according to the present embodiment, the development process of PDL data and the adjustment process are executed in parallel, thereby maintaining the machine state (particularly the image quality) by the adjustment process and reducing the downtime experienced by the user. It is possible to achieve both mitigation.

1 is an exemplary schematic cross-sectional view of an image forming apparatus according to an embodiment. It is an exemplary block diagram of the control part which concerns on embodiment. It is a figure which shows an example of the management table of the example adjustment process item which concerns on embodiment. It is a flowchart about the process performed in the controller 103 among the control methods which concern on embodiment. It is a flowchart about the process performed in the engine control part 104 among the control methods which concern on embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 103 ... Controller 104 ... Engine control part 105 ... First color image forming unit 106 ... Second color image forming unit 107 ... Third color image forming unit 108 ... Fourth color image forming unit 109 ... Intermediate transfer belt 113 ... Pattern detection sensor 114 ... Secondary transfer roller 115 ... Belt cleaner 116 ... Pre-registration roller 117 ... Registration sensor 118 ... Registration roller 119 ... Conveyor belt 120 ... Fixing device

Claims (6)

An image forming apparatus,
A developing unit for developing data for forming an image;
An image forming apparatus comprising: an adjustment unit that executes an adjustment process for maintaining the machine state of the image forming apparatus in parallel with the development of the data. A determination unit that determines whether or not the development of the data is completed before the adjustment process is completed;
When the development of the data is completed before the adjustment process is completed, an interruption control unit that interrupts the adjustment process;
The image forming apparatus according to claim 1, further comprising: A determination unit that determines whether or not a request related to the start of image formation on a recording medium is received during the adjustment process;
When it is determined that the request has been received during execution of the adjustment process, an interruption control unit that interrupts the adjustment process;
The image forming apparatus according to claim 1, further comprising: A management unit that manages the number of times that the adjustment process is interrupted;
4. The image forming apparatus according to claim 2, further comprising a forcible control unit that forcibly executes the adjustment process during or after execution of the image formation when the number of times exceeds a threshold value. 5. An estimation unit for estimating a development time required for the development of the data;
A storage unit that stores an execution time required for each of the plurality of adjustment processes;
A comparison unit that reads out the execution time of the adjustment process that needs to be executed from the storage unit, and compares the execution time with the estimated expansion time;
Including
The adjustment unit is
The image forming apparatus according to claim 1, wherein the adjustment processing is executed in parallel with the development of the image data when the development time is longer than the execution time. An image forming apparatus control method comprising:
Developing data for forming an image;
And a step of executing an adjustment process for maintaining the body state of the image forming apparatus in parallel with the development of the data.

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