JP2011022231A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suitably determine whether to stop a calibration when a printing request occurs during the calibration. <P>SOLUTION: On accepting image data during performance of the calibration, when the number of sheets which is the number of sheets regarding the printing of the image data added to an accumulated printed number of sheets when the calibration is performed is less than the calibration limit number of sheets, a calibration control part stops the calibration and an image forming part performs the printing based on the image data. In this case, when the added number of sheets is a calibration limit number of sheets or more, the calibration control part continues the calibration as it is and the image forming part performs the printing based on the image data after termination of the calibration. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image forming apparatus which forms a toner image by attaching toner to an image carrier on which an electrostatic latent image is formed, and forms the image by transferring the toner image onto a sheet.

  Conventionally, in an image forming apparatus such as a copier, a printer, a facsimile, etc., an electrical or mechanical state applied to an image forming output is changed due to a change in an environment in which the apparatus is placed, deterioration or wear of parts, etc. End up. When such a change occurs, the image quality such as the color and density of the image differs before and after the change, making it impossible to supply a stable image quality.

  Therefore, in order to maintain the image quality of the output image constant, bias calibration for adjusting the output density by correcting the development bias voltage applied to the developing device and correction of the gamma table describing the output density data for the input density data are performed. The I / O calibration to be performed is performed in the apparatus. Hereinafter, these are collectively referred to as “calibration”. Patent Documents 1 and 2 describe techniques related to calibration execution timing.

JP 2005-258959 A JP 2006-189725 A

  In the conventional method, when a print request is generated during calibration, the current calibration is stopped and printing is executed in order to prioritize printing. However, during this printing, if the cumulative number of prints from the previous calibration reaches the limit that cannot guarantee image quality maintenance unless calibration is performed, the current print is interrupted, and the calibration that was canceled is canceled. It was resuming. In this case, even if a print request is generated, the calibration can be continued without stopping, and the printing can be completed earlier by executing the printing after the calibration is completed.

  SUMMARY An advantage of some aspects of the invention is that it provides an image forming apparatus that appropriately determines whether or not to cancel calibration when a print request is generated during calibration. It is what.

  According to a first aspect of the present invention, there is provided an image forming apparatus that receives an input of image data, an image forming unit that prints an image based on the image data received by the receiving unit, and a previous calibration. A counting unit that counts the cumulative number of printed sheets printed by the image forming unit later, and when the cumulative number of printed sheets reaches a predetermined number of calibration executions during the non-execution period of the calibration, Control means for instructing execution of calibration for correcting the output density of the image, and when the receiving means receives image data during execution of the calibration, the control means performs the calibration. The number of prints obtained by adding the number of prints related to printing of the image data to the cumulative number of prints at the time of execution is If the number of calibration is greater than or equal to a predetermined number of calibration limits, the calibration is continued. If the number is less than the calibration limit, the calibration is stopped and When the calibration is stopped, the image forming unit is caused to form an image based on the image data received by the receiving unit.

  According to this configuration, whether to execute calibration or cancel when the receiving unit receives image data (when a print request is made) during calibration is performed according to the number of prints related to printing of image data. Can be determined. In other words, if the number of calibration limits is not reached even after printing based on the image data received during calibration, the calibration is stopped and printing based on the image data is prioritized, and the number of calibration limits is exceeded. In such a case, a problem such as image quality degradation occurs, so calibration is continued without stopping. That is, it is possible to optimize the determination of execution or cancellation of calibration, and it is possible to improve user convenience.

  According to a second aspect of the present invention, in the image forming apparatus according to the first aspect, the image forming apparatus further includes a first setting input receiving unit that receives a setting input of the calibration execution number and the calibration limit number.

  According to this configuration, since the user can arbitrarily set the number of calibration executions and the limit number of calibrations, user convenience can be improved.

  According to a third aspect of the present invention, in the image forming apparatus according to the first or second aspect, the calibration control unit is configured such that the transmission source of the image data received by the receiving unit during the execution of the calibration is in advance. In the case of a sender having a low printing urgency, the calibration limit number is changed to the cumulative number of printed sheets when the calibration is executed.

  According to this configuration, it is possible to determine whether to execute or cancel the calibration when the receiving unit receives the image data during the execution of the calibration according to the printing urgency of the transmission source of the image data. Therefore, it is possible to optimize the determination of execution or cancellation of calibration, and improve user convenience.

  According to a fourth aspect of the present invention, in the image forming apparatus according to the third aspect, among the transmission sources from which the reception unit can receive the image data, the predetermined transmission source with low printing urgency. Second setting input receiving means for receiving the setting input is further provided.

  According to this configuration, since the user can arbitrarily set the transmission source with low printing urgency, the convenience of the user can be improved.

  A fifth aspect of the present invention is the image forming apparatus according to any one of the first to fourth aspects, wherein the calibration control unit receives the image data received by the receiving unit during the execution of the calibration. When the print priority is lower than a predetermined print priority, the calibration limit number of sheets is changed to the cumulative number of printed sheets when the calibration is executed.

  According to this configuration, it is possible to determine whether to execute or cancel the calibration when the receiving unit receives the image data during the execution of the calibration according to the print priority of the image data. Calibration execution or cancellation determination can be optimized, and user convenience can be improved.

  A sixth aspect of the present invention is the image forming apparatus according to the fifth aspect, further comprising third setting input receiving means for receiving a setting input of the predetermined printing priority.

  According to this configuration, since the user can arbitrarily set a predetermined printing priority, the convenience for the user can be improved.

  According to the present invention, it is possible to optimize the determination of execution or cancellation of calibration, and it is possible to improve user convenience.

FIG. 2 is a side view schematically showing an internal configuration of the image forming apparatus. 1 is a block diagram illustrating an electrical configuration of an image forming apparatus. FIG. 6 is a diagram for explaining a case where a determination condition (1) is used for the number of printed sheets. Judgment condition (2) is a diagram for explaining a case where printing urgency of a transmission source of image data is used. The figure which showed an example of the data structure of the low printing urgency transmission origin memory | storage part. Judgment condition (3) is a diagram for explaining a case where the print priority of image data is used. The figure which showed an example of the data structure of the low printing priority memory | storage part. The flowchart which showed the flow of printing and a calibration process.

  Hereinafter, an embodiment of an image forming apparatus according to the present invention will be described with reference to the drawings. FIG. 1 is a side view schematically showing an internal configuration of an image forming apparatus 1 according to an embodiment of the present disclosure. The image forming apparatus 1 has functions such as a copy function, a printer function, a scanner function, and a facsimile function. The image forming apparatus 1 includes a main body 2, a stack tray 3 disposed on the left side of the main body 2, and a main body. 2 has a document reading unit 4 disposed above the document reading unit 4 and a document feeding unit 33 disposed above the document reading unit 4.

  An input operation unit 6 is provided on the front part of the image forming apparatus 1. The input operation unit 6 displays a start key 7 for a user to input a print execution instruction, a numeric keypad 8 for inputting the number of copies to be printed, operation guide information for various copying operations, and the like. A display unit 9 composed of a liquid crystal display or the like having a touch panel function for input, a reset key 10 for resetting setting contents set on the display unit 9, and a stop for stopping a printing (image forming) operation being executed A key 11 and a function switching key 12 for switching between a copy function, a printer function, a scanner function, and a facsimile function are provided.

The document reading unit 4 includes a scanner unit 13 including a CCD (Charge Coupled Device) sensor and an exposure lamp, and a document table 14 and a document reading slit 15 made of a transparent member such as glass. The scanner unit 13 is configured to be movable by a drive unit (not shown). When reading a document placed on the document table 14, the scanner unit 13 is moved along the document surface at a position facing the document table 14, and the document image is displayed. Image data acquired while scanning is output to a control unit described later. Further, when reading the document fed by the document feeding unit 33, the document is moved to a position facing the document reading slit 15 and synchronized with the document feeding operation by the document feeding unit 33 via the document reading slit 15. The original image is acquired, and the image data is output to the control unit.

  The document feeding unit 33 includes a document placement unit 16 for placing a document, a document discharge unit 17 for discharging a document whose image has been read, and a document placed on the document placement unit 16. A document transport mechanism 18 including a paper feed roller, a transport roller (not shown), and the like for feeding the paper one by one to a position facing the document reading slit 15 and discharging it to the document discharge section 17 is provided.

  Further, the document feeding unit 33 is provided so as to be rotatable with respect to the main body unit 2 so that the front side thereof can move upward. By moving the front side of the document feeder 33 upward to open the upper surface of the document table 14, the operator can place a read document, for example, a book in a spread state, on the upper surface of the document table 14. It has become.

  The main body 2 includes a plurality of paper feed cassettes 19, a paper feed roller 20 that feeds the paper from the paper feed cassette 19 one by one and transports it to the image forming unit 21, and an image on the paper transported from the paper feed cassette 19. And an image forming unit 21 for forming the image.

  The image forming unit 21 outputs a laser beam or the like based on the image data acquired by the scanner unit 13 to expose the photosensitive drum 22, and forms an electrostatic latent image on the surface of the photosensitive drum 22. A developing unit 24 that forms a toner image by attaching toner to the surface of the photosensitive drum 22 on which the electrostatic latent image is formed, and a transfer unit 25 that transfers the toner image on the photosensitive drum 22 to a sheet. A fixing device 28 provided with a fixing roller 26 and a pressure roller 27 for heating the paper on which the toner image is transferred to fix the toner image on the paper, and a paper conveying path in the image forming unit 21; Are provided with a pair of conveying rollers 30 and 31 and the like.

  The density sensor 55 measures the density of the toner image formed on the photosensitive drum 22, and is composed of, for example, a reflective photosensor. In this case, the density sensor 55 emits light to the toner image on the photosensitive drum 22 from a light emitting unit such as a light emitting diode, and the light receiving unit such as a photodiode detects the amount of reflected light. The optical density of the image (hereinafter simply referred to as “density”) is measured. The measured concentration is output to the control unit described later.

  When images are formed on both sides of a sheet, the image forming unit 21 forms an image on one side of the sheet, and then the sheet is nipped between the pair of conveying rollers 30 on the discharge tray 29 side. In this state, the conveyance roller pair 30 is reversed to switch back the sheet, and the sheet is sent to the sheet conveyance path 32 to be conveyed again to the upstream area of the image forming unit 21. The image forming unit 21 forms an image on the other surface. After that, the paper is discharged to the stack tray 3 or the discharge tray 29.

  FIG. 2 is a block diagram illustrating an electrical configuration of the image forming apparatus 1. The image forming apparatus 1 includes a control unit 51, a storage unit 52, an image memory 53, an image processing unit 54, an image forming unit 21, a density sensor 55, a document reading unit 4, an input operation unit 6, a network I / F unit 56, a memory. An I / F unit 57 and a FAX communication unit 58 are provided. In addition, the same code | symbol is attached | subjected to the same component as demonstrated using FIG. 1, and description is abbreviate | omitted.

  The storage unit 52 stores programs, data, and the like for realizing various functions of the image forming apparatus 1. The image memory 53 temporarily stores image data acquired by the document reading unit 4 and image data transmitted from an external device via the network I / F unit 56, the memory I / F unit 57, and the FAX communication unit 58. . The image processing unit 54 performs image processing such as image correction and enlargement / reduction on the image data stored in the image memory 53.

  The network I / F unit 56 includes a communication module such as a LAN board, and transmits / receives data to / from an external device such as the personal computer 71 via the network line 61. The memory I / F unit 57 is an interface that can be connected to an external storage device. The FAX communication unit 58 can be connected to the public line 63, performs outgoing / incoming control for the facsimile 73 connected to the public line, and transmits / receives data to / from the facsimile 73.

  In the present embodiment, as a medium capable of transmitting / receiving data to / from the image forming apparatus 1, a personal computer 71 connected to the network line 61, a USB memory 72 connected to the USB cable 62, and a public line 63 are connected. The facsimile 73 will be described as an example, but other network (line) or data transmission path may be used as long as image data can be transmitted to the image forming apparatus 1.

  The control unit 51 is configured by a CPU (Central Processing Unit) or the like, reads a program stored in the storage unit 52 and executes processing, and outputs an instruction signal to each functional unit, data transfer, and the like. And controlling the image forming apparatus 1 in an integrated manner, and includes a cumulative print number counting unit 511, a calibration control unit 512, a calibration number storage unit 513, a low printing urgency transmission source storage unit 514, and a low printing priority. A storage unit 515 is included.

  The accumulated print number counting unit 511 counts the accumulated number of prints after the previous calibration is executed. Note that, after the calibration is completed, the cumulative print number counting unit 511 resets the cumulative print number.

  The calibration control unit 512 corrects the developing bias voltage applied to the developing unit 24 and executes calibration for adjusting the output density of the toner image. Specifically, first, the calibration control unit 512 causes the image forming unit 21 to form toner patches having different densities. Next, the density sensor 55 is made to measure the density of the formed toner patch, and the toner patch closest to the preset density is detected. Then, the development bias voltage when the toner patch detected as being closest to the preset density is formed is set to the development bias voltage during normal printing.

  The calibration control unit 512 determines the calibration execution timing based on the number of calibration execution sheets stored in the calibration sheet number storage unit 513 and the count value of the accumulated printing sheet number counting unit 511. The calibration number storage unit 513 stores two values, a calibration execution number and a calibration limit number. The calibration execution number stores the cumulative number of prints for which it is difficult to guarantee image quality maintenance unless calibration is executed. For example, when the number of calibration executions stored in the calibration number storage unit 513 is 900, the calibration control unit 512 executes the calibration when the count value by the cumulative printing number counting unit 511 becomes 900 or more.

  The limit number of calibrations means that when the document reading unit 4 acquires image data from a document during calibration, the network I / F unit 56, the memory I / F unit 57, and the FAX communication unit 58 This is the number of sheets used when the calibration control unit 512 determines whether or not to cancel calibration when image data is received, and is set to a number larger than the number of calibration execution sheets.

  The calibration control unit 512 is configured such that when the document reading unit 4 acquires image data from a document during calibration, the network I / F unit 56, the memory I / F unit 57, and the FAX communication unit 58 perform image processing. When the data is received, it is determined whether to cancel the calibration in progress and print an image based on the image data or to continue the calibration. The judgment conditions at this time include (1) the number of printed sheets, (2) the printing urgency of the image data transmission source, and (3) the printing priority of the image data.

  First, a case where (1) the number of printed sheets is used as a determination condition will be described with reference to FIG. In FIG. 3A, at time t11 when printing 1 is completed, the calibration control unit 512 compares the cumulative number of prints from the previous calibration with the number of calibration executions, and the cumulative number of prints is equal to or greater than the number of calibration executions. If yes, perform calibration. In the case of FIG. 3A, since the cumulative number of printed sheets is 910, which is 900 or more after the completion of printing 1, the calibration control unit 512 executes calibration.

  At time t12, the document reading unit 4 acquires image data from the document, or any of the network I / F unit 56, the memory I / F unit 57, and the FAX communication unit 58 receives the image data. It is assumed that the number of printed sheets for image data printing is 50 sheets. The number of printed sheets may be stored in advance as image data properties, or the control unit 51 may calculate the number of printed sheets from the size of the image data and the size of the printing paper.

  The calibration control unit 512 compares the number of prints of image data added to the cumulative number of prints at the time of calibration execution with the limit number of calibrations. When the number of prints of image data added to the cumulative number of prints at the time of calibration execution is less than the limit number of calibrations, the calibration control unit 512 stops the calibration being executed. Then, the control unit 51 causes the image forming unit 21 to execute printing based on the image data.

  FIG. 3A shows a case in which image data with 50 printed sheets is received during calibration. In this case, the total number of prints 910 at the time of calibration execution plus the number of prints 50 is 910 + 50 = 960, and the calibration limit unit 512 is less than 1000, so the calibration control unit 512 The calibration is stopped, and the control unit 51 causes the image forming unit 21 to execute printing 2 based on the image data. After the end of printing 2 (time t13), the calibration control unit 512 resumes calibration.

  On the other hand, FIG. 3B shows a case in which image data with 100 printed sheets is received during calibration. In this case, the total number of prints 910 at the time of calibration execution plus the number of prints 100 is 910 + 100 = 1100, which is the limit number of calibration 1000 or more. Therefore, if the calibration is stopped and printing based on the image data is prioritized and executed, the image quality cannot be maintained, and the calibration control unit 512 continues the calibration as it is. Then, after the calibration is completed (time t14), the control unit 51 causes the image forming unit 21 to execute printing 2 based on the image data.

  In summary, when image data is received during calibration execution, (1) when determining whether or not to cancel calibration based on the number of prints, the image data is printed on the cumulative number of prints at the time of calibration execution. If the added number is less than the calibration limit number, the calibration control unit 512 stops the calibration, the image forming unit 21 executes printing based on the image data, and the calibration limit number If so, the calibration control unit 512 continues the calibration as it is, and after the calibration is completed, the image forming unit 21 executes printing based on the image data.

  Next, a case where (2) the printing urgency of the image data transmission source is used as the determination condition will be described. Here, the printing urgency of the transmission source of the image data is preset with respect to the origin of the image data (the document reading unit 4, the personal computer 71, the USB memory 72, the facsimile 73, etc.). It is set according to whether or not printing should be executed immediately after reception. The urgency of printing for each transmission source is preferably set according to the convenience of the user.

  For example, image data transmitted from a personal computer 71 or a facsimile machine 73 connected to the network 61 is often not inconvenient even if it is not immediately printed. Accordingly, the personal computer 71 and the facsimile machine 73 connected to the network 61 as the transmission source set the printing urgency low. On the other hand, the image data acquired by the document reading unit 4 and the image data transmitted from the USB memory 72 are set by the user directly on the document feeding unit 33 or the user directly stores the USB memory 72 in the memory I / O. Since it is mounted on the F section 57, it is often convenient that the user exists near the image forming apparatus 1 and printing is started immediately. Therefore, the document reading unit 4 and the USB memory 72 as the transmission source set a high printing urgency.

  The printing urgency of each transmission source may be preset when the image forming apparatus 1 is designed, or may be arbitrarily set by the user via the input operation unit 6. FIG. 5 is a diagram illustrating an example of a data configuration of the low printing urgency transmission source storage unit 514. The low printing urgency transmission source storage unit 514 stores an interface name that receives image data from a transmission source that is set to have a low printing urgency. That is, when the printing urgency of image data transmitted from the personal computer 71 connected to the network 61 or the facsimile 73 connected to the public line 63 is set low, the low printing urgency transmission source storage unit 514 stores the personal computer 71. A “network I / F unit” that receives image data transmitted from the FOMA terminal and a “FAX communication unit” that receives image data transmitted from the facsimile machine 73 are stored.

  The stored contents of the low printing urgency transmission source storage unit 514 can be arbitrarily set by the user via the input operation unit 6. In this case, the control unit 51 changes the content of the low printing urgency transmission source storage unit 514 in accordance with a user operation.

  Then, when the interface stored in the low printing urgency transmission source storage unit 514 receives image data during calibration execution, the calibration control unit 512 sets the number of calibration executions to the cumulative number of prints at the time of calibration execution. change. Then, the number of prints of image data added to the cumulative number of prints at the time of calibration is compared with the changed calibration limit number. If the cumulative number of prints at the time of calibration is 910, the limit number of calibrations is changed to 910, and the number of prints of image data added to the cumulative number of prints at the time of calibration is naturally the calibration. Over the limit number Therefore, the calibration control unit 512 continues the calibration without interruption, and executes printing based on the received image data after the calibration is completed.

  On the other hand, when an interface that is not stored in the low printing urgency transmission source storage unit 514 receives image data, the calibration control unit 512 stops the calibration that is being performed, and the control unit 51 adds the received image data to the received image data. Based on this, the image forming unit 21 is caused to execute printing. Then, after the end of printing, the calibration control unit 512 resumes calibration.

  With reference to FIG. 4, the flow when (2) the printing urgency of the image data transmission source is used as the determination condition will be described. At time t21 when printing 1 is completed, the calibration control unit 512 compares the cumulative number of prints from the previous calibration with the number of calibration executions, and executes calibration if the cumulative number of prints is equal to or greater than the number of calibration executions. To do. In the case of FIG. 4A, since the cumulative number of printed sheets is 910, which is 900 or more after the completion of printing 1, the calibration control unit 512 executes calibration.

  Here, FIG. 4A shows a case where the memory I / F unit 57 receives image data at time t22. In this case, the calibration control unit 512 determines whether or not the interface that has received the image data is an interface stored in the low printing urgency transmission source storage unit 514. When the data configuration of the low printing urgency transmission source storage unit 514 is as shown in FIG. 5, the memory I / F unit 57 is not stored in the low printing urgency transmission source storage unit 514, and thus the calibration control unit 512. Stops the calibration being executed, and the control unit 51 causes the image forming unit 21 to execute printing 2 based on the received image data. After the end of printing 2 (time t23), the calibration control unit 512 resumes calibration.

  On the other hand, FIG. 4B shows a case where the FAX communication unit 58 receives image data at time t22. In this case, the calibration control unit 512 determines whether or not the interface that has received the image data is an interface stored in the low printing urgency transmission source storage unit 514. Since the FAX communication unit 58 is stored in the low printing urgency transmission source storage unit 514, the calibration control unit 512 changes the number of calibration executions to the cumulative number of printings (910) at the time of calibration execution. Then, the number of prints of image data added to the cumulative number of prints at the time of calibration is compared with the changed calibration limit number. Since the limit number of calibrations is changed to 910, the number of prints of image data added to the cumulative number of prints at the time of calibration is naturally greater than or equal to the limit number of calibrations. Therefore, the calibration control unit 512 continues the calibration being executed. Then, after the calibration is completed (time t24), the control unit 51 causes the image forming unit 21 to execute printing 2 based on the received image data.

  In summary, when image data is received during calibration execution, whether or not to cancel the calibration is determined by (2) the printing urgency of the image data transmission source, the interface that received the image data Is not stored in the low printing urgency transmission source storage unit 514, the calibration control unit 512 stops the calibration, and the image forming unit 21 executes printing based on the image data. When the interface that has received the image data is stored in the low printing urgency transmission source storage unit 514, the calibration control unit 512 changes the number of calibration executions to the cumulative number of printings at the time of calibration execution. Then, the calibration control unit 512 compares the number of prints of image data added to the cumulative number of printed sheets at the time of calibration execution with the changed number of calibration limit sheets. Since the number of prints has been changed, the number of prints of image data added to the number of prints at the time of calibration is naturally equal to or greater than the limit number of calibrations. That is, the calibration control unit 512 continues the calibration as it is, and after the calibration is completed, the image forming unit 21 executes printing based on the image data.

  Next, a case where (3) the print priority of image data is used as the determination condition will be described. Here, the “print priority” is set by the user so that when image data (print job) is transmitted from a plurality of external devices, the user prints his / her own image data before other image data. Information. The print priority has, for example, three levels of “low”, “normal”, and “high”. If the print priority of the image data is not particularly set, the “normal” level is automatically added. However, if the user wants to prioritize printing of the image data, the user operates the external apparatus to set the print priority of the image data to “high” and transmits the image data to the image forming apparatus 1. As a result, the control unit 51 causes the image forming unit 21 to print the image data with the print priority “high” before the image data with the print priority “low” or “normal”.

  Note that the print priority of the image data acquired by the document reading unit 4 may be set in advance, for example, “print priority = normal”, or the user may use the input operation unit 6 when reading the document. It may be set arbitrarily via

  With reference to FIG. 6, (3) the flow when the print priority of image data is used will be described. At time t31 when printing 1 is completed, the calibration control unit 512 compares the cumulative number of prints from the previous calibration with the number of calibration executions, and executes calibration if the cumulative number of prints is equal to or greater than the number of calibration executions. To do. In the case of FIG. 6A, since the cumulative number of printed sheets is 910, which is 900 or more after the completion of printing 1, the calibration control unit 512 executes calibration.

  Here, FIG. 6A shows a case where image data with a high print priority = high is received at time t32. The calibration control unit 512 determines whether the print priority of the image data is the same as the print priority stored in the low print priority storage unit 515. FIG. 7 is a diagram illustrating an example of a data configuration of the low printing priority storage unit 515. For example, it is assumed that the print priority set in the low print priority storage unit 515 is “low, normal”. In this case, since the print priority of the received image data is different from the print priority stored in the low print priority storage unit 515, the print based on the received image data is prioritized and executed from the calibration being executed. It shows that it should be made. Accordingly, the calibration control unit 512 stops the calibration being executed, and the control unit 51 causes the image forming unit 21 to execute printing 2 based on the received image data. After the end of printing 2 (time t33), the calibration control unit 512 resumes calibration.

  On the other hand, FIG. 6B shows a case where print priority = normal image data is received at time t32. In this case, the calibration control unit 512 executes the printing based on the received image data because the printing priority of the received image data is the same as the printing priority stored in the low printing priority storage unit 515. It shows that the calibration inside is given priority. Therefore, the calibration control unit 512 changes the number of calibration execution sheets to the cumulative number of printed sheets (910 sheets) at the time of calibration execution. Then, the number of prints of image data added to the cumulative number of prints at the time of calibration is compared with the changed calibration limit number. Since the limit number of calibrations is changed to 910, the number of prints of image data added to the cumulative number of prints at the time of calibration is naturally greater than or equal to the limit number of calibrations. Therefore, the calibration control unit 512 continues the calibration being executed. After the calibration is completed (time t34), the control unit 51 causes the image forming unit 21 to execute printing 2 based on the received image data.

  Note that the content stored in the low print priority storage unit 515 can be arbitrarily set by the user via the input operation unit 6. In this case, the control unit 51 changes the contents of the low printing priority storage unit 515 in accordance with a user operation.

  In summary, when image data is received during calibration execution, it is determined whether the calibration is to be stopped using (3) the print priority of the image data. If the print priority is different from the print priority stored in the low print priority storage unit 515, the calibration control unit 512 stops the calibration, and the image forming unit 21 executes printing based on the image data. If the print priority of the image data is the same as the print priority stored in the low print priority storage unit 515, the calibration control unit 512 changes the calibration execution number to the cumulative number of prints at the time of calibration execution. To do. Then, the number of prints of image data added to the cumulative number of prints at the time of calibration is compared with the changed calibration limit number. Since the limit number of calibration sheets is changed to the cumulative number of printed sheets at the time of calibration execution, the number of prints of image data added to the cumulative number of printed sheets at the time of calibration is naturally greater than or equal to the limit number of calibration sheets. That is, the calibration control unit 512 continues the calibration as it is, and after the calibration is finished, the image forming unit 21 executes printing based on the image data.

  FIG. 8 is a flowchart showing the flow of printing and calibration processing in the present embodiment. In FIG. 8, the case where the above-mentioned determination condition (1) the number of printed sheets is used will be described. When the document reading unit 4 acquires image data, or when any of the network I / F unit 56, the memory I / F unit 57, or the FAX communication unit 58 receives the image data (step S11), the image forming unit 21 Performs printing based on the image data (step S12). Then, the cumulative print number counting unit 511 adds the print number to the cumulative print number (step S13).

  The calibration control unit 512 compares the cumulative number of printed sheets with the number of calibration executed sheets (900 sheets in the above example). If the cumulative number of printed sheets is smaller (step S14; NO), the control unit 51 proceeds to step S11. Transition. On the other hand, when the cumulative number of printed sheets is equal to or greater than the number of calibration execution sheets (step S14; YES), the calibration control unit 512 executes calibration (step S15).

  When the document reading unit 4 acquires image data during calibration or any of the network I / F unit 56, the memory I / F unit 57, or the FAX communication unit 58 receives the image data. (Step S16; YES), the calibration control unit 512 compares the number of prints of the received image data and the cumulative number of prints with the limit number of calibrations (Step S17). When the number of prints of the image data and the cumulative number of prints is less than the limit number of calibrations (step S17; YES), the calibration control unit 512 stops the calibration that is being performed and the image forming unit 21 Printing based on the data is executed (step S18). Then, after the printing is finished (step S19; YES), the calibration control unit 512 resumes the calibration (step S20), and after the calibration is finished, the cumulative printed number counting unit 511 resets the cumulative printed number (step S21). . If the power is not turned off (step S26; NO), the control unit 51 proceeds to step S11.

  On the other hand, when the sum of the number of printed image data and the cumulative number of prints is equal to or greater than the calibration limit number (step S17; NO), the calibration control unit 512 continues the calibration being executed (step S22). Then, after the calibration is completed (step S23; YES), the cumulative printed number counting unit 511 resets the cumulative printed number (step S24). Then, the image forming unit 21 executes printing based on the image data (step S25), and the control unit 51 shifts the processing to step S13.

  Also, the original reading unit 4 did not acquire image data during calibration, or any of the network I / F unit 56, the memory I / F unit 57, or the FAX communication unit 58 did not receive image data. When the calibration is completed (step S16; NO), after the calibration is completed (step S27; YES), the control unit 51 shifts the process to step S21.

  Note that the flowchart of FIG. 8 has described the case where (1) the number of printed sheets is used as a determination condition for determining whether or not the calibration control unit 512 stops the calibration being executed. When (2) the printing urgency of the transmission source of the image data described above is used, the interface where the calibration control unit 512 receives the image data is the low printing urgency transmission source storage unit 514 in step S17 of FIG. And whether or not to cancel or continue calibration is determined and processed. If the determination condition is (3) print priority of image data, the calibration control unit 512 stores the print priority of image data and the priority stored in the low print priority storage unit 515 in step S17 of FIG. Are compared to determine whether to stop or continue calibration.

  As described above, the document reading unit 4 acquires image data during calibration, or the network I / F unit 56, the memory I / F unit 57, or the FAX communication unit 58 receives the image data. (1) Number of prints, (2) Printing urgency of image data transmission source, (3) Printing of image data By making the determination based on the priority, it is possible to optimize the determination of execution or cancellation of the calibration, and the convenience of the user can be improved.

  In the present embodiment, (1) the number of printed sheets, (2) the printing urgency of the transmission source of image data, 3) Although the print priority of the image data has been described separately, a plurality of determination conditions may be combined.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Main-body part 3 Stack tray 4 Original reading part (accepting means)
6 Input operation unit (first setting input receiving means, second setting input receiving means, third setting input receiving means)
21 Image forming unit (image forming means)
51 Control unit (control means)
511 Cumulative print count section (counting means)
512 Calibration control unit (control means)
513 Calibration number storage unit 514 Low printing urgency transmission source storage unit 515 Low printing priority storage unit 56 Network I / F unit (accepting means)
57 Memory I / F section (reception means)
58 FAX communication section (accepting means)

Claims (6)

Receiving means for receiving input of image data;
Image forming means for printing an image on paper based on the image data received by the receiving means;
A counting means for counting the cumulative number of printed sheets printed by the image forming means after the previous calibration;
Control means for instructing the image forming means to execute calibration for correcting the output density of the image when the cumulative number of printed sheets reaches a predetermined number of calibration executions during the calibration non-execution period When,
And when the receiving unit receives image data during execution of the calibration, the control unit adds the number of prints related to the printing of the image data to the cumulative number of prints when the calibration is executed. If the number is equal to or greater than a predetermined calibration limit number that is greater than the number of calibration executions, the calibration is continued, and if the number is less than the calibration limit number, the calibration is stopped and the execution is performed. An image forming apparatus for causing the image forming unit to form an image based on the image data received by the receiving unit when the calibration is stopped.   The image forming apparatus according to claim 1, further comprising a first setting input receiving unit that receives setting inputs of the calibration execution number and the calibration limit number.   The calibration control means, when the transmission source of the image data received by the reception means during execution of the calibration is a predetermined transmission source with a low printing urgency, the calibration limit number The image forming apparatus according to claim 1, wherein the image forming apparatus is changed to a cumulative number of printed sheets at the time of execution.   The image according to claim 3, further comprising: a second setting input receiving unit that receives a setting input of the predetermined transmission source with low printing urgency among the transmission sources from which the receiving unit can receive the image data. Forming equipment.   When the calibration control unit executes the calibration for the number of calibration limit sheets when the print priority of the image data received by the reception unit during the calibration is lower than a predetermined print priority. The image forming apparatus according to claim 1, wherein the image forming apparatus is changed to the cumulative number of printed sheets.   The image forming apparatus according to claim 5, further comprising a third setting input receiving unit that receives a setting input of the predetermined printing priority.

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