JP2015004890A - Image forming apparatus, image forming method, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus which performs an efficient sequence control for a print job and a calibration job while minimizing a cooling stand-by period when performing scanning with a spectral colorimetric sensor in executing calibration.SOLUTION: Provided is an image forming apparatus which performs printing based on a plurality of print jobs. The image forming apparatus comprises: means for acquiring information of a sheet to be fed, for each print job; means for determining whether or not calibration processing is needed for each print job according to the number of sheets output; means for determining the fixation temperature in executing the calibration on the basis of the information of the sheet to be fed; means for determining the fixation temperature in normal printing on the basis of the information of the sheet to be fed; and means for shuffling the jobs by comparing the fixation temperatures of the jobs to allow the print order of a print job having a lower fixation temperature to precede a print job accompanied by the calibration processing.

Description

  The present invention relates to an image forming apparatus, an image forming method, and a program. Specifically, the present invention relates to an image forming apparatus, an image forming method, and a program for correcting the color of an image output from a printer.

  In recent years, with the improvement in performance of image forming apparatuses, the image forming apparatus can realize image quality equivalent to that of a printing press. However, it is known that the image forming apparatus changes its printing characteristics due to the influence of the environment in which the image forming apparatus is installed. Therefore, the image forming apparatus has a problem that the density or color at the time of printing changes due to temperature or humidity of the installation environment, aging of the apparatus, or parts replacement, and a stable printed matter cannot be obtained. There is.

  In order to solve this problem, the image forming apparatus is generally equipped with a calibration technique. The calibration technique is a technique for correcting gradation characteristics of toner used for printing. Several patches with different gradations are printed with a known toner amount, and their density is measured using a scanner or sensor connected to the image forming apparatus. A gradation correction LUT (look-up table) is generated so that the measurement result is in accordance with a known target density target. By applying the generated tone correction LUT when printing is performed, it is possible to obtain a stable output that matches the target characteristics.

  By the way, as a cause of the change in the printing characteristics, in addition to the above-described factors of the image forming apparatus, the characteristics of the paper used for printing are greatly affected. There are various types of paper used for printing, and the sizes, basis weights, surface properties, and chromaticity of the paper itself are different. Even if the characteristics of the image forming apparatus are the same, if the printing paper is different, the density characteristics of the printing result are also different. For this reason, the image forming apparatus has a plurality of target densities for each paper type, performs calibration, and holds the generated correction LUT. By selecting and applying an appropriate correction LUT according to the paper used at the time of printing, the influence of the paper is reduced. In this specification, a combination of a specific sheet and a correction LUT is called a calibration set.

  In general, an image forming apparatus has a plurality of paper feed stages for storing a plurality of sheets at the same time. Each image forming apparatus can store different types of paper, and an appropriate paper is selected according to the setting required in the print job and printing is executed. As described above, the paper and the density characteristic of the printing result are closely related. In an image forming apparatus that can calibrate for each paper, the paper selected at the time of calibration and the target value to be targeted Are associated with each other.

  In view of this, a technique has been proposed in which when a calibration is executed, a paper feed stage in which a sheet to be used at the time of calibration is stored is specified (see Patent Document 1).

  Further, the image forming apparatus can be provided with various sensors, and for example, it is possible to measure the density during calibration using a density sensor. In recent years, there are image forming apparatuses equipped with chromaticity sensors capable of automatically measuring chromaticity and density with high accuracy. Equipped with a sensor with sufficient reading range and accuracy to execute calibration, realizing a means to automatically execute calibration continuously by setting multiple calibration sets when executing calibration can do. By using such means, it is possible to realize an image forming apparatus that reduces the calibration work load of the operator. In particular, in a calibration system using a spectrocolorimetric sensor, not only a single color such as CMYK but also a mixed color (multi-order color) expressed by a combination of each color can be measured. Creation is also possible.

  There is also known a phenomenon (thermochromism) in which the color of the object to be measured changes depending on the temperature of the object to be measured at the time of measurement. This phenomenon occurs due to a change in color due to the influence of a fluorescent substance (fluorescent whitening agent contained in the object to be measured) or a change in color due to the influence of a non-fluorescent substance (coloring material component). The color value measurement by the spectrocolorimetric sensor is more influenced by thermochromism than the density measurement by the densitometer.

JP 2011-43815 A JP 2008-238459 A

  When creating a calibration chart in an image forming apparatus with a spectrophotometric sensor installed inside (specifically, before the paper exit), immediately after fixing to the spectrophotometric sensor to avoid measurement errors It is necessary to devise a method that does not scan a chart with excessive heat. For this reason, it is necessary to make the chart stand by on the transport path so that it is sufficiently cooled before colorimetry and is not affected by thermochromism. Since the fixing temperature and the degree of heat storage differ from paper to paper, an appropriate fixing temperature for each type of printing paper and cooling time management are required (if the fixing temperature at the time of chart image printing is high, the paper cooling time will be longer). Become). From such a background, it is desirable to control the fixing temperature of the device so as not to increase more than necessary before the calibration of the spectrocolorimetric sensor.

  On the other hand, when a print job that requires calibration and a normal print job that does not require calibration are waiting in the job list, there is a means to improve productivity by giving priority to normal print jobs. It has been proposed (see Patent Document 2).

  The present invention realizes the order control of a print job with such calibration and a normal print job with an image forming apparatus equipped with a spectral colorimetric sensor. In such an image forming apparatus, due to an increase in fixing temperature due to a priority job, the processing time (cooling time) of calibration processing using a spectrocolorimetric sensor is increased, and the productivity of the image forming apparatus is reduced. was there.

  In order to solve the above problems, an image forming apparatus of the present invention is an image forming apparatus that performs printing based on a plurality of print jobs, and obtains information on paper to be fed for each print job; Means for determining whether or not calibration processing is required for each print job, means for determining a fixing temperature at the time of calibration from the information on the paper to be fed, and paper feeding By comparing the fixing temperature for each job with the means for determining the fixing temperature during normal printing from the information on the paper, the job is switched, and the print order of the print job with the low fixing temperature is changed to a print job with calibration processing. And a means for preceding.

  In the present invention, the overtaking control of the print job is performed based on the fixing temperature, and when the fixing temperature of the subsequent print job is higher than the fixing temperature of the print job accompanied by the leading calibration process, the switching of the printing order is suppressed. As a result, it is possible to prevent the temperature of the fixing device from rising above the temperature required for the calibration process and the waiting time for cooling before reading by the spectrocolorimetric sensor. According to the present invention, it is possible to realize an image forming apparatus that can efficiently control the order of a print job and a calibration job while minimizing a cooling standby time when scanning with a spectral colorimetric sensor during calibration.

1 is a configuration diagram of a printing system according to Embodiments 1 and 2. FIG. 1 is a hardware configuration diagram of an image forming apparatus according to Embodiments 1 and 2. FIG. FIG. 3 is a software configuration diagram of the image forming apparatus according to the first and second embodiments. FIG. 3 is a fixing temperature determination / printing order determination sequence diagram according to the first exemplary embodiment. FIG. 10 is a fixing temperature determination / printing order determination sequence diagram according to the second exemplary embodiment. 6 is a flowchart of fixing temperature determination processing according to the first and second embodiments. 6 is a flowchart of printing order determination processing according to the first and second embodiments. FIG. 6 is a detailed view of a calibration threshold number table according to the first and second embodiments. FIG. 3 is a detailed view of a fixing temperature table and a cooling time table of Examples 1 and 2. It is a detailed view of a measurement chart for calibration in Examples 1 and 2.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the first embodiment, the information processing apparatus outside the image forming apparatus performs PDL analysis processing / RIP processing, and transfers the RIP-completed data via the network. On the other hand, in the second embodiment, PDL analysis processing / RIP processing is performed inside the main body of the image forming apparatus.

  In the present invention, the configurations described in FIGS. 3, 4A, 4B, 5A, and 5B are partially different for each embodiment, but the configurations described in the other drawings are common. Hereinafter, Example 1 and Example 2 will be described for each drawing.

[Configuration of printing system]
FIG. 1A is a configuration diagram of a printing system according to the first embodiment and the second embodiment, and includes a block diagram illustrating an image forming apparatus. The image forming apparatus 100 includes a developing station 101, a fixing station 102, and a paper feed deck 109. The controller 130 controls each element constituting the image forming apparatus 100. The operation unit 150 has both an LCD and a touch panel, and an operator of the image forming apparatus can check the printing status via the operation unit 150 and perform various settings. The scanner 160 reads a document. By transferring the read document as image information to the controller 130, the copy function can be executed. In each of the CMYK developing devices 104 to 107, an input image from the controller 130 is developed on a photosensitive drum built in each developing device, and the toner adheres to the developing unit to form a toner image on the photosensitive drum. . The developed CMYK toner images are transferred to the intermediate transfer belt 108, and then transferred to a recording medium (specifically, a sheet) fed from the paper feed deck 109. The sheet having the toner image transferred thereon is sent to the fixing station 102, and heat and pressure are applied by the fixing roller 110. As a result, the toner is melted and fixed on the sheet, and the image forming process is completed. If necessary, the sheet is reversed by the reversing unit 140 and discharged. A spectral colorimetric sensor 170 is installed in the reversing unit 140.

  FIG. 1B is an enlarged view for explaining the operation of the reversing unit 140 of the image forming apparatus according to the first and second embodiments of the present invention. A plurality of spectral colorimetric sensors 170 can be installed in the reversing unit 140 in parallel. In this embodiment, it is assumed that two spectral colorimetric sensors 170 are installed (see FIG. 8). The measurement chart 800 conveyed to the reversing unit 140 reaches the butting plate 180 at the lower end of the reversing unit 140. If necessary, the measurement chart 800 is stopped at this position for a certain period of time and waits until the heat of the measurement chart 800 is naturally cooled. After waiting, the measurement chart 800 is switched back, and the measurement patches formed on the measurement chart 800 are continuously read by the spectrocolorimetric sensor 170 while being conveyed upward.

[Hardware configuration of image forming apparatus]
FIG. 2 is a block diagram illustrating a hardware configuration of the controller 130 of the image forming apparatus. The CPU 201, RAM 202, UI I / F 203, Network I / F 204, ROM 205, and HDD 206 are connected via the SystemBus 220, and these communicate with each other. Components on the SystemBus 220 access the RIP 208, the printer image processing unit 209, and the engine I / F 210 connected to the ImageBus 230 via the ImageBus I / F 207. The print job control unit 305, the PDL analysis unit 313-1, the RIP image control unit 314-1, the print page control unit 307, etc., which will be described later, are executed on the CPU 201, and temporary data being processed is stored in the RAM 202. Is done. The UI I / F 203 is connected to the operation unit 211 and notifies a signal from the operation unit 211 to each module. The network I / F 204 receives stream type PDL data from the information processing apparatus via the network and stores it in the HDD 206. The ROM 205 stores various parameters and programs necessary for starting and executing the image forming apparatus, and is accessed from each software module as necessary. The HDD 206 temporarily stores PDL data received via the network. The HDD 206 is accessed from each module as a data swap area for the RIP 208 and the printer image processing unit 209. ImageBus I / F207 handles communication between SystemBus220 and ImageBus230. Specifically, the ImageBus I / F 207 handles communication between a module on the SystemBus220 side on which control system software operates and a module related to page image processing that operates on the ImageBus230. The RIP 208 (RIP is an abbreviation for raster image processor) connected to the ImageBus 230 expands a page description language (PDL) code into an image file. A printer image processing unit 209 performs resolution conversion processing and correction processing suitable for the printer engine 212 on the image file generated by the RIP 208. The engine I / F 210 is a communication I / F for the engine control unit 315 to control the printer engine 212 through the engine I / F 210. The spectral colorimetric sensor 213 is connected to the engine I / F 210 via the printer engine 212 and reads a chart at the time of calibration. The printer engine 212 includes an engine control unit 315 that controls the developing station 101 and the fixing station 102 shown in FIG.

[Software configuration of image forming apparatus]
FIG. 3 is a block diagram illustrating a software configuration of the controller 130 of the image forming apparatus 100. Here, each module will be described based on the second embodiment, and finally, differences between the first embodiment and the second embodiment will be described.

  Each component included in the print job control unit 305, the PDL analysis unit 313-1, and the UI screen control unit 330 is stored in one of the storage means of the ROM 205, RAM 202, and HDD 206 connected to the SystemBus 220 and executed by the CPU 201. The The RIP image control unit 314-1 operates in cooperation with the RIP 208 and the printer image processing unit 209 connected to the ImageBus 230 in addition to the above-described H / W component connected to the SystemBus 220.

  The engine control unit 315 controls the printer engine 212 in cooperation with the engine I / F 210 connected to the ImageBus 230 in addition to the above-described H / W component connected to the SystemBus 220.

  The network I / F 301 provides a TCP / IP socket I / F to the network control unit 302. The information processing apparatus 190 generates PDL data using an application, and transmits PDL data such as PDF, PostScript, PCL, XPS, TIFF, JPEG, etc. using one of RAW / LPR transmission protocols. The network control unit 302 supports the RAW / LPR communication protocol, and the image forming apparatus 100 receives PDL data. The image forming apparatus 100 sequentially writes the received PDL data as stream data to the HDD 206 via the Data reception control unit 303 and the reception buffer 304. When the network control unit 302 receives data, the print job control unit 305 recognizes the start of reception of the print job and starts processing the print job.

  The print job control unit 305 activates the PDL analysis unit 313-1 and instructs the PDL analysis unit 313-1 to read the PDL data stored in the HDD 206. The PDL analysis unit 313-1 expands and analyzes the PDL data read from the HDD 206 to acquire finishing information such as the paper size, paper type, and paper feed specification of the input data, and analyzes the drawing command for each page -Perform drawing processing. The intermediate page data rendered by the PDL analysis unit 313-1 is stored in the intermediate page storage unit 309. The intermediate page data stored in the intermediate page storage unit 309 is subjected to RIP processing in the RIP image control unit 314-1 and stored in the print page storage unit 310 as an image optimized for the engine.

  When the PDL analysis unit 313-1 detects information such as the paper size and paper type of a page, the information is passed to the page attribute storage unit 308 of the print page control unit 307. In particular, in the analysis process of the first page of the print job, not only the page information but also the job attribute information related to the setting of the entire document is determined by the PDL analysis unit 313-1 and the job attribute storage unit 306 of the print job control unit 305 is determined. Stored in

  The print control unit 311 includes a fixing temperature management unit 312. The print control unit 311 acquires the “job attribute” of the job attribute storage unit 306 and the “page attribute” of the page attribute storage unit 308 at the start of printing, and feeds them to the engine control unit 315 according to these pieces of information. Instruct. In response to a paper feed instruction to the engine control unit 315, the print control unit 311 inquires the fixing temperature management unit 312 and determines a necessary fixing temperature from parameters of the paper to be fed.

  The engine control unit 315 performs a paper discharge process at a speed and interval according to the characteristics of each finisher.

  The calibration control unit 317 determines whether or not calibration processing is necessary in response to an inquiry from the print job control unit 305, and performs the calibration processing when it is determined that calibration processing is necessary. The calibration control unit 317 includes a calibration threshold value management unit 318, a calibration chart storage unit 319, and a spectral colorimetric sensor control unit 320 therein. At the time of calibration, the chart image stored in the calibration chart storage unit 319 is transferred to the print control unit 311. The print control unit 311 outputs the chart image through the engine control unit 315. Scan with a colorimetric sensor. The image scanned using the spectrocolorimetric sensor control unit 320 is compared with a reference value, and feedback adjustment for the print parameters of the engine control unit 315 is performed.

  In response to a request from the job attribute storage unit 306, the calibration threshold management unit 318 notifies the number of sheets that can be output continuously without executing the corresponding calibration based on the information on the paper size, paper type, and paper feed stage.

  The calibration chart storage unit 319 stores an image at the time of calibration execution, and passes the stored image to the print control unit 311 when outputting the chart for calibration. The spectral colorimetric sensor control unit 320 controls a processing flow in which the spectral colorimetric sensor scans the chart image. The cooling time management unit 321 holds a table of cooling time until the chart paper immediately after fixing is sufficiently cooled and the spectral colorimetric sensor can be scanned. By referring to this table, the cooling time can be acquired from the output paper information (paper size / paper type).

  Next, a difference between the first embodiment and the second embodiment will be described. In the first embodiment, PDL analysis processing and RIP processing are performed outside the image forming apparatus 100. Therefore, the image forming apparatus 100 according to the first embodiment includes a page attribute transfer control unit 313-2 that receives the PDL analysis result from the external information processing apparatus 190, and a page data transfer control unit 314-2 that receives the RIP image. With. On the other hand, in the second embodiment, PDL analysis processing and RIP processing are performed in the image forming apparatus 100. Therefore, the image forming apparatus 100 according to the second embodiment includes a PDL analysis unit 313-1 and a RIP image control unit 314-1.

[Print order control sequence]
The sequence of printing order control will be described with reference to FIG.

  FIG. 4A is a sequence diagram of printing order control in consideration of fixing temperature and cooling time during calibration in a system that performs PDL analysis processing and RIP processing outside the image forming apparatus 100 (that is, the sequence of the first embodiment). It is a figure).

  In order to determine whether to change the printing order, calibration adjustment occurs during job processing, and information on the fixing temperature at the time of calibration and information on the cooling period required by the spectral colorimetric sensor are required.

  In the first embodiment, since PDL analysis processing is performed outside the image forming apparatus 100, information on the paper size, type, and paper feed stage used in the job is determined at the first stage when the image forming apparatus receives the job. doing. Therefore, job replacement control can be performed in consideration of the processing time during calibration at the initial stage of starting job processing.

  The sequence in FIG. 4A is composed of the following three parts.

  In the first group 41100, print job data is received via the network, and immediately after that, from information such as “paper source, paper size, paper type information” used at the time of printing set as the job attribute from the outside. Check in advance whether calibration will occur. When calibration occurs, the time required for calibration is calculated from the fixing temperature and the subsequent cooling time before being read by the spectral colorimetric sensor.

  In the first group 41100, first, the print job control unit stores the type and number of media used in the job, such as the paper feed stage, paper size, and paper type, in the job attribute storage unit (reference numeral in FIG. 4A). 41001). Next, the job attribute storage unit checks whether there is a medium exceeding the calibration execution interval threshold in the calibration threshold management unit (reference numeral 41002 in FIG. 4A). Based on the result of this confirmation, the fixing temperature of the medium corresponding to the case of executing calibration and the cooling time before reading by the spectral colorimetric sensor after fixing are confirmed (reference numeral 41003 in FIG. 4A). Finally, the print job control unit acquires the fixing temperature for each job from the job attribute storage unit (reference numeral 41004 in FIG. 4A).

  In the second group 41200, page attribute information that has undergone PDL analysis processing / RIP processing on the external information processing apparatus 190 and page data are transferred to the components of the image forming apparatus 100.

  In the second group 41200, first, the print job control unit instructs the page attribute transfer control unit to start receiving RIP-completed data (job unit) (reference numeral 41005 in FIG. 4A). Next, the print job control unit requests the print page control unit to generate a page processor (reference numeral 41006 in FIG. 4A). Next, the print page control unit requests the page attribute transfer control unit to acquire page attributes (reference numeral 41007 in FIG. 4A). Next, the print page control unit acquires the page attribute from the page attribute transfer control unit (reference numeral 41008 in FIG. 4A). Next, the print page control unit stores the acquired page attribute in the page attribute storage unit (reference numeral 41009 in FIG. 4A). Next, the print page control unit requests the page data transfer control unit to start video transfer processing (reference numeral 41010 in FIG. 4A). Next, the print page control unit receives a video transfer process end notification from the page data transfer control unit (reference numeral 41011 in FIG. 4A). Finally, the page attribute transfer control unit notifies the print job control unit of the completion of reception of RIP-completed data (in units of jobs) (reference numeral 41012 in FIG. 4A).

  In the third group 41300, print job order determination and print processing are performed.

  In the third group 41300, the print job control unit first determines the order of the print jobs according to the flowchart of FIG. 5B (reference numeral 41013 in FIG. 4A). Specifically, the print job control unit compares the order of the current job and the subsequent job. If there is no subsequent job, or if the subsequent job has not been processed until operation 41004, the print processing 41014 to 41017 is performed without performing job order determination. On the other hand, if there is a subsequent job, the replacement determination is performed according to the flowchart of FIG. 5B, and after the printing order is determined, operations 41014 to 41017 are repeated for the page of the corresponding job, and all pages are output and the process ends. The printing processes 41014 to 41017 will be described. The print job control unit notifies the print page control unit of the start of print processing (page unit) (reference numeral 41014 in FIG. 4A). Next, the print page control unit notifies the print control unit of the start of print processing (page unit) (reference numeral 41015 in FIG. 4A). Next, the print control unit notifies the print page control unit of the end of print processing (page unit) (reference numeral 41016 in FIG. 4A). Finally, the print page control unit notifies the print job control unit of the end of print processing (page unit) (reference numeral 41017 in FIG. 4A).

  FIG. 4B is a sequence diagram of printing order control in consideration of the fixing temperature and the cooling time during calibration in a system that performs PDL analysis processing and RIP processing on the image forming apparatus 100 (that is, the sequence diagram of the second embodiment). Is).

  As described above, the determination of changing the print order includes the occurrence of calibration adjustment during job processing, the information on the fixing temperature at the time of calibration, and the information on the cooling period required by the spectral colorimetric sensor. is necessary. In order to perform these determinations / calculations, it is necessary to determine the paper size, paper type, and paper feed stage information used in the job.

  For this reason, when PDL analysis processing and RIP processing are performed on the image forming apparatus 100, the print size is determined after the paper size, paper type, and paper feed stage information to be used in the job are determined along with the PDL development processing. Take control.

  The sequence in FIG. 4B is composed of the following three parts.

  In the first group 42100, PDL job data is received via a network, and PDL analysis processing and RIP processing are performed on the image forming apparatus 100.

  In the first group 42100, first, the print job control unit instructs the PDL analysis unit to start PDL development processing (in units of jobs) (reference numeral 42001 in FIG. 4B). Next, the print job control unit instructs the print page control unit to generate a page processor (reference numeral 42002 in FIG. 4B). Next, the print page control unit instructs the PDL analysis unit to start page generation (reference numeral 42003 in FIG. 4B). Next, the end of page generation is notified from the PDL analysis unit to the print page control unit (reference 42004 in FIG. 4B). Next, the print page control unit stores the page attribute in the page attribute storage unit (reference numeral 42005 in FIG. 4B). Next, the print page control unit instructs the RIP control unit to start RIP processing (reference numeral 42006 in FIG. 4B). Next, the end of the RIP process is notified from the RIP control unit to the print page control unit (reference 42007 in FIG. 4B). After the operations 42002 to 42007 are repeated a plurality of times according to the number of pages in the job, the end of the PDL development process is notified from the PDL analysis unit to the print job control unit (reference 42008 in FIG. 4B).

  In the second group 42200, whether or not calibration occurs during the print operation of the job based on the information such as the paper feed stage, paper size, and paper type used in the job obtained from the result of the PDL analysis processing. Determine whether. When calibration occurs, the fixing temperature and the cooling time required before reading with the spectral colorimetric sensor are calculated as the time required for calibration.

  In the second group 42200, first, the print job control unit issues a job attribute acquisition request such as the presence / absence of calibration and the fixing temperature to the job attribute storage unit (reference 42009 in FIG. 4B). Next, the job attribute storage unit confirms whether or not calibration execution information and information regarding the fixing temperature are stored in the attribute information of the job. If there is no necessary information in the attribute information of the job, the job attribute storage unit requests the page attribute storage unit to acquire attribute information such as the paper size, paper type, and designated paper feed level of all pages. Obtain (reference numeral 42010 in FIG. 4B). Next, the job attribute storage unit performs ON / OFF determination of calibration execution by inquiring of the calibration threshold management unit based on the acquired page information, and stores the determination result as a job attribute (reference numeral in FIG. 4B). 42011). Details of this processing will be described later with reference to the flowchart of FIG. 5A. Next, the job attribute storage unit checks the fixing temperature at the time of printing with the fixing temperature management unit based on the acquired page information. When the calibration is executed, either the fixing temperature at the time of calibration or the fixing temperature at the time of normal printing is confirmed (reference numeral 42012 in FIG. 4B). The fixing temperature is determined for each paper type (see FIG. 7A). Next, the fixing temperature during the printing process is notified from the job attribute storage unit to the print job control unit (reference numeral 42013 in FIG. 4B).

  In the third group 42300, the printing order is switched based on the calculation result of the second group 42200, and the printing process is performed in the job order after the switching.

  In the third group 42300, first, the print job control unit compares the order of the current job and the subsequent job (reference numeral 42014 in FIG. 4B). If there is no subsequent job, or if the subsequent job has not been processed until operation 42013, the print processing 42015 to 42018 is performed as it is without determining the job order. On the other hand, if there is a subsequent job, the replacement determination is performed according to the flowchart of FIG. 5B. Next, the print job control unit instructs the print page control unit to start print processing (page unit) (reference numeral 42015 in FIG. 4B). Next, the print page control unit instructs the print control unit to start print processing (page unit) (reference numeral 42016 in FIG. 4B). Next, the print control unit notifies the print page control unit of the end of print processing (page unit) (reference numeral 42017 in FIG. 4B). Finally, the print page control unit notifies the print job control unit of the end of print processing (page unit) (reference numeral 42018 in FIG. 4B). The operation sequence 42015 to 42018 is repeated for the number of pages of the job, and printing is finished.

[Fixing temperature determination processing and printing order determination processing]
FIG. 5A is a flowchart showing a series of processes for determining the basis weight and fixing temperature of each page in a print job.

  First, in step S5101, print job information (specifically, a job ID) is acquired from the job list.

  Next, in step S5102, PDL expansion processing is performed for the corresponding job ID data. Paper information necessary for print job calibration determination is determined at the beginning of the PDL development process. Also, information necessary for print job calibration determination is finalized on the last page of the PDL development processing.

  Next, in step S5103, it is determined whether or not the job is a print job that is affected by the calibration correction effect. If it is determined that the job is a print job that is affected by the calibration correction effect, the process advances to step S5104. If it is determined that the job is not a print job that is affected by the calibration correction effect, the process advances to step S5109.

  In step S5104, the received data is analyzed, and the paper size / paper type / basis weight of all print pages used in the print job and the paper feed stage information are obtained and fed from each paper feed stage. Predict the number of sheets to be printed. Also, determination information for determining whether or not the job is permitted to change the printing order from the information processing apparatus 190 is acquired.

  Next, in step S5105, an inquiry is made to the calibration threshold value management unit 318 based on the predicted number of fed sheets.

  Next, in step S5106, it is determined in advance whether or not calibration processing occurs during processing of the job. If it is determined that the calibration process does not occur, the process proceeds to step S5109. If it is determined that the calibration process occurs, the process is performed after the information of the paper size / paper type / paper feed stage is confirmed. Advances to step S5107.

  In step S5107, the fixing temperature and the cooling time are calculated from the information of the paper size / paper type / paper feed stage to be calibrated.

  In step S5108, the information of “fixing temperature”, “cooling time”, and “calibration ON” acquired in steps S5106 and S5107 is stored as job attributes.

  In step S5109, the fixing temperature management unit 312 is inquired, and the fixing temperature of the normal print job is acquired from the information of the paper size / paper type / paper feed stage to be printed.

  In step S5110, the information “fixing temperature” and “calibration OFF” are stored as job attributes.

  FIG. 5B shows a series of processes for determining whether or not to change the order of the print jobs from the attribute information (specifically, the fixing temperature) for each print job, and changing the order of the print jobs as necessary. It is a flowchart.

  First, in step S5201, information on the first job and information on the next job are acquired from the job list for order comparison determination.

  Next, in step S5202, by referring to the calibration ON / OFF flag of the first job, it is determined whether or not to execute calibration (that is, whether or not a waiting time for cooling occurs). If it is determined that calibration is to be executed, the process proceeds to step S5203. If it is determined that calibration is not to be performed, the process proceeds to step S5207.

  In step S5203, the fixing temperature of each job is acquired from the job attribute of the first job and the job attribute of the subsequent job.

  In step S5204, the fixing temperature of the first job is compared with the fixing temperature of the subsequent job. If the fixing temperature of the first job is higher than the fixing temperature of the subsequent job, the process proceeds to step S5205. If the fixing temperature of the first job is equal to or lower than the fixing temperature of the subsequent job, the process proceeds to step S5207.

  In step S5205, based on the determination information for determining whether or not the change of the print order acquired in step S5104 is permitted, it is determined whether or not the order of the first job and the subsequent job can be switched. If it is determined that the order of the first job and the subsequent job can be switched, the process proceeds to step S5206. If it is determined that the order of the first job and the subsequent job cannot be switched, the process proceeds to step S5206. Proceed to step S5207.

  In step S5206, the order of the leading job and the succeeding job is changed, and the succeeding job having a low fixing temperature is preceded.

  Finally, in step S5207, print processing of the job at the head of the job list is performed.

[Calibration threshold number table]
FIG. 6 is a table for managing the threshold value of the calibration execution interval for each paper feed stage. The table 600 is a table that holds threshold values for managing the number of calibration intervals for each sheet in the sheet feed tray. The table 600 is stored in the calibration threshold value management unit 318 and is updated each time output from the print control unit 311. Each column of the table 600 will be described. Column 601 holds the paper feed stage, column 602 holds the paper size set for the paper feed stage, column 603 holds the paper type set for the paper feed stage, and column 604 Holds the basis weight of the paper set in the paper feed stage. Here, it should be noted that the column 605 holds the adjustment threshold value, that is, the number of sheets that can be continuously output without calibration. Since this threshold is provided for each paper feed stage, a total of 4 records (for 4 paper feed stages) are registered in the example of FIG. Next, each row of the table 600 will be described. Data corresponding to “cassette 1, A4, plain paper 1” in line 611, data corresponding to “cassette 2, A4, plain paper 2” in line 612, “cassette 3, A3, plain paper 3” in line 613 Corresponding data, data corresponding to “cassette 4, A3, cardboard 1” is held in row 614. Each paper feed stage holds the number of sheets that can be continuously fed without performing calibration.

[Fixing temperature table, cooling time table]
FIG. 7A is a table for managing the fixing temperature, and FIG. 7B is a table for managing the cooling time. The table 700 is a table for calculating the fixing temperature from the paper type information held by the fixing temperature management unit 312. Each column of the table 700 will be described. A column 701 holds a paper name type, a column 702 holds a permissible sheet basis weight range, and a column 703 holds a sheet fixing temperature. Next, each row of the table 700 will be described. In the example of FIG. 7A, data corresponding to “plain paper 1” is held in the row 705, data corresponding to “plain paper 2” is held in the row 706, and “plain paper” is stored in the row 707. 3 ”is held, and data corresponding to“ thick paper 1 ”is held in a row 708.

  The table 720 is a table for calculating the cooling time from the paper type information held by the cooling time management unit 321. Each column of the table 720 will be described. A column 721 holds a paper name type, a column 722 holds a permissible sheet basis weight range, and a column 723 holds a sheet cooling time. Next, each row of the table 720 will be described. In the example of FIG. 7B, data corresponding to “plain paper 1” is held in the row 725, data corresponding to “plain paper 2” is held in the row 726, and “plain paper” is stored in the row 727. 3 ”is held, and data corresponding to“ Thick Paper 1 ”is held in the row 728.

[Measurement chart for calibration]
FIG. 8 is a detailed diagram relating to a measurement chart for calibration in the first and second embodiments. FIG. 8 shows a sample measurement chart 800 for calibration. This sample is stored in the calibration chart storage unit 319 as an output image. The colorimetric patch in the width 801 is scanned by the spectral colorimetric sensor 803, and the colorimetric patch in the width 802 is scanned by the spectral colorimetric sensor 804. The spectral colorimetric sensors 803 and 804 are installed on the reversing path in the fixing station 102 and read the patch when the measurement chart 800 is switched back in the direction of the arrow in FIG.

  In the first and second embodiments, the overtaking control of the print job is performed based on the fixing temperature, and the printing order is changed when the fixing temperature of the subsequent print job is higher than the fixing temperature of the first calibration job. Suppress. As a result, it is possible to realize an image forming apparatus that efficiently controls the order of the print job and the calibration job while minimizing the cooling standby time when scanning with the spectrocolorimetric sensor during calibration.

[Other Examples]
The object of the present invention can also be achieved by executing the following processing. That is, a storage medium in which a program code of software for realizing the functions of the above-described embodiments is recorded is supplied to a system or apparatus, and a computer (or CPU or MPU) of the system or apparatus is stored in the storage medium. This is the process of reading the code. In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiments, and the program code and the storage medium storing the program code constitute the present invention.

Claims (6)

An image forming apparatus that prints based on a plurality of print jobs,
Means for obtaining information of paper to be fed for each print job;
Means for determining whether or not calibration processing is required for each print job from the number of output sheets;
Means for determining a fixing temperature at the time of calibration from information on the paper to be fed;
Means for determining a fixing temperature during normal printing from information on the paper to be fed;
An image forming apparatus comprising: a means for replacing jobs by comparing the fixing temperature for each job, and for causing a print job with a low fixing temperature to precede a print job with a calibration process. .   The image forming apparatus according to claim 1, wherein it is determined using a job attribute whether or not a job for performing replacement determination is permitted to change a printing order. PDL analysis means for analyzing PDL data received from an external information processing device;
The image forming apparatus according to claim 1, further comprising a RIP image control unit that performs RIP processing on the intermediate page data.   2. The image forming apparatus according to claim 1, wherein the means for determining whether or not calibration processing is required for each print job from the number of sheets to be output is determined by making an inquiry to a calibration threshold management means. apparatus. An image forming method in which an image forming apparatus controls a printing order of a plurality of print jobs,
Obtaining paper feed information for each print job;
Determining whether calibration processing is required for each print job based on the number of sheets to be output;
Determining a fixing temperature at the time of calibration from the information of the paper to be fed;
Determining a fixing temperature during normal printing from information on the paper to be fed;
An image forming method comprising: replacing jobs by comparing fixing temperatures for each job, and causing a print job with a low fixing temperature to precede a print job with calibration processing. .   The program for functioning a computer as an image forming apparatus as described in any one of Claims 1 thru | or 4.

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