Image diagnostic system and image diagnostic method

Abstract

To solve the problem in which: since a user cannot grasp the printing number of charts for diagnosis before printing the charts for diagnosis, image diagnosis may be interrupted due to paper shortage during the printing of the charts for diagnosis.SOLUTION: An image diagnostic system displays, on an operating unit, a screen for receiving an instruction for image diagnosis, in accordance with the operating unit receiving an instruction for starting image diagnosis, causes an image forming unit to form an image for diagnosis on a sheet, causes a reading unit to read the image for diagnosis that has been formed and output, and diagnoses a malfunction portion of the image forming unit on the basis of an image obtained through the reading. The screen includes the number of images for diagnosis to be output.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to an image diagnostic system and an image diagnostic method. [Background technology]

[0002] There is an image diagnosis technology in which an image forming apparatus is provided with a printing unit and an image reading unit, a diagnostic chart printed by the printing unit is read by the image reading unit, and faults in the apparatus are diagnosed from image data. Patent Document 1 discloses a technology for reading images of recording media on which patterns including horizontal and vertical band charts are printed, and for identifying items requiring image diagnosis based on the read images. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-133020 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in Patent Document 1, there is no means for notifying the user of the number of diagnostic charts to be printed before printing the diagnostic charts. Therefore, the user cannot know the number of diagnostic charts to be printed before printing the diagnostic charts, and image diagnosis may be interrupted in the middle of printing the diagnostic charts due to a lack of paper. [Means for solving the problem]

[0005] The image diagnostic system of the present invention comprises an operation unit that displays information, an image forming unit consisting of multiple parts that forms an image on paper, a reading unit that reads the image formed by the image forming unit, a display control means that causes the operation unit to display a screen that accepts instructions for image diagnosis, and a diagnostic means that, in response to an instruction received by the operation unit to start image diagnosis, causes the image forming unit to form a diagnostic image on paper, causes the reading unit to read the formed and output diagnostic image, and diagnoses defective areas of the image forming unit based on the image obtained by the read operation, and is characterized in that the screen includes the number of diagnostic images output. Effect of the Invention

[0006] According to the present invention, it is possible to grasp the number of diagnostic images to be output before performing a diagnosis. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing an example of a network configuration including a printing system. [Diagram 2] FIG. 1 is a cross-sectional view showing an example of a hardware configuration of an image forming apparatus. [Diagram 3] Block diagram showing the internal configuration of the image forming device, external controller, and client PC [Figure 4] Flowchart showing the procedure of image diagnosis processing [Diagram 5] A diagram showing an example of a diagnostic item selection screen [Figure 6] A diagram showing an example of notification of the number of test charts to be used in image diagnosis processing [Figure 7] Figure showing an example of notification of the number of test charts to be used for automatic recovery processing [Figure 8] Schematic diagram of a table used to calculate the number of test charts used in image diagnostic processing [Figure 9] Schematic diagram of a table used to calculate the number of test charts to be used for automatic recovery processing [Figure 10] A diagram showing an example of a test chart used in image diagnostic processing. [Figure 11] A diagram showing an example of a diagnostic item selection screen [Figure 12] FIG. 11 is a diagram showing an example of notification of the range of the number of test charts used in image diagnosis processing in a modified example of the first embodiment. [Figure 13] FIG. 13 is a diagram showing an example of a warning message when notifying the user of the number of test charts to be used in image diagnosis processing in a modified example of the first embodiment; [Figure 14] FIG. 11 is a flowchart showing the procedure of a simple image diagnosis process in the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. Note that the same components are given the same reference numerals and the description will be omitted.

[0009] [First embodiment] <System configuration> Fig. 1 is a diagram showing an example of a network configuration including a printing system (image diagnosis system) according to this embodiment. As shown in Fig. 1, the printing system 100 includes an image forming apparatus 101 and an external controller 102. The image forming apparatus 101 and the external controller 102 are communicatively connected via an internal LAN 105 and a video cable 106. The external controller 102 is communicatively connected to a client PC 103 via an external LAN 104.

[0010] The client PC 103 can issue a print instruction to the external controller 102 via the external LAN 104. A printer driver having a function of converting image data to be printed into a page description language (PDL) that can be processed by the external controller 102 is installed in the client PC 103. A user who wishes to print can issue a print instruction from various applications installed in the client PC 103 via the printer driver by operating the client PC 103. The printer driver transmits PDL data, which is print data, to the external controller 102 based on a print instruction from the user. When the external controller 102 receives the PDL data from the client PC 103, it analyzes and interprets the received PDL data. Based on the result of the interpretation, it performs a rasterization process to generate a bitmap image (print image data) with a resolution matching the image forming apparatus 101, and issues a print instruction by submitting a print job to the image forming apparatus 101.

[0011] Next, the image forming apparatus 101 will be described. In the image forming apparatus 101, a plurality of devices having different functions are connected, and it is configured to be capable of complex printing processes such as bookbinding. The image forming apparatus 101 has a printing unit 107 (image forming unit), a diagnosis unit 108, a stacker 109, and a finisher 110. Each module will be described below.

[0012] The printing unit 107 prints an image in accordance with a print job and ejects the printed recording material. The printed recording material ejected from the printing unit 107 is transported inside each device in the order of the diagnosis unit 108, stacker 109, and finisher 110. In this embodiment, the image forming device 101 of the printing system 100 is an example of an image forming device, but the printing unit 107 included in the image forming device 101 may also be referred to as an image forming device. The printing unit 107 forms (prints) an image using toner (color material) on the recording material fed and transported from a paper feed unit arranged below the printing unit 107.

[0013] The diagnosis unit 108 is a device that diagnoses the presence or absence of a defect in the image forming apparatus 101 based on the printed recording material on which an image has been printed by the printing unit 107 and which has been transported through a transport path. Specifically, the diagnosis unit 108 reads the image printed on the transported printed recording material, and performs diagnosis from the obtained read image. The defect is diagnosed by extracting a diagnosis area from the read image, and confirming the difference in read signal values ​​within the extracted diagnosis area. Detailed processing by the diagnosis unit will be described later. Note that the use of the diagnosis unit is not limited to the above example. The diagnosis unit may also be provided with an inspection function for inspecting the presence or absence of printing defects on the printed recording material.

[0014] The stacker 109 is a device capable of stacking a large number of printed recording materials. The finisher 110 is a device capable of executing finishing processes such as stapling, punching, and saddle stitching on the conveyed printed recording materials.

[0015] The recording material processed by the finisher 110 is discharged onto a predetermined discharge tray.

[0016] 1, an external controller 102 is connected to the image forming apparatus 101, but this embodiment can also be applied to a different configuration. For example, a configuration may be used in which the image forming apparatus 101 is connected to an external LAN 104, and print data is sent from a client PC 103 to the image forming apparatus 101 without going through the external controller 102. In this case, data analysis and rasterization of the print data are performed by the image forming apparatus 101.

[0017] <Hardware Configuration of Image Forming Apparatus 101> 2 is a cross-sectional view showing an example of the hardware configuration of the image forming apparatus 101. A specific operation example of the image forming apparatus 101 will be described below with reference to FIG.

[0018] <Description of the paper feed deck> The printing unit 107 includes a plurality of paper feed decks. In this embodiment, six types of decks, paper feed decks 361, 362, 363, 364, 365, and 366, are included. Various recording materials (paper) are stored in each paper feed deck. Of the recording materials stored in each paper feed deck, the uppermost recording material is separated one by one and fed to the conveying path 303. The paper feed deck also acquires paper information of the stored paper based on a sensor and an instruction from the user. In this embodiment, the paper information refers to the size, basis weight, surface properties, and color of the paper. This paper information is acquired and stored in a HDD, which will be described later. The paper size refers to the finished dimensions of the paper as defined by ISO216. In this embodiment, in addition to A size and B size, the size of photo paper can be identified. Basis weight is information expressed as the weight of cardboard, which is the standard for paper, and is expressed as the weight per 1 m 2 In this embodiment, the mass per unit area is 79 g / m 2 Below (thin paper), 80g / m 2 More than 127g / m 2 Below (plain paper), 128g / m 2 More than 200g / m 2 or less (cardboard), 201g / m 2 The above (heavy paper 2) is classified into four stages. Surface quality is information that expresses the difference in paper type due to the unevenness of the paper surface. In this embodiment, there are seven types: fine paper, single-sided coated paper, double-sided coated paper, matte coated paper, embossed paper, film paper, and recycled paper.

[0019] Finally, the paper color is information that indicates the whiteness of the paper as defined by, for example, ISO 12470. In this embodiment, a whiteness of 70% or more is determined to be white, and a whiteness of less than that is determined to be colored paper. Table 1 shows a schematic example of the paper information that is stored.

[0020] The paper size is automatically acquired by reading the position of a guide (not shown) in the paper feed deck with a sensor. Other information is acquired by the user selecting and inputting from a paper information change screen described later. Note that, in the present embodiment, an example has been described in which only a portion of the paper information is acquired by a sensor provided in the paper feed deck, but this is not limited to the above example. For example, a configuration may be adopted in which a sheet of paper stored in the paper feed deck is passed through, and the paper information is determined based on an image read by a reading device described later.

[0021] [Table 1]

[0022] The deck ID and paper information are stored for each of the six types of paper feed decks. The level at which the paper information is determined is not limited to the above example. It is sufficient that the resolution is sufficient to determine whether or not the compatibility conditions of the image diagnosis test chart, which will be described later, are met, and the determination may be made at a finer level. As a more preferable example, a sensor is mounted on the paper feed deck and information is automatically acquired, but a configuration in which the user registers the paper information himself or herself may also be used.

[0023] Each of the image forming stations 304 to 307 includes a photosensitive drum (photoconductor) and forms a toner image on the photosensitive drum using toner of a different color. Specifically, the image forming stations 304 to 307 form a toner image using toner of yellow (Y), magenta (M), cyan (C), and black (K), respectively.

[0024] The toner images of each color formed in the image forming stations 304 to 307 are transferred onto the intermediate transfer belt 308 in order, superimposed on top of each other (primary transfer). The toner images transferred onto the intermediate transfer belt 308 are transported to a secondary transfer position 309 as the intermediate transfer belt 308 rotates. At the secondary transfer position 309, the toner image is transferred from the intermediate transfer belt 308 onto the recording material transported along the transport path 303 (secondary transfer). The recording material after the secondary transfer is transported to a fixing unit 311. The fixing unit 311 includes a pressure roller and a heating roller. Heat and pressure are applied to the recording material while the recording material passes between these rollers, thereby performing a fixing process in which the toner image is fixed onto the recording material. The recording material that has passed through the fixing unit 311 is transported to a connection point 315 between the printing unit 107 and the diagnosis unit 108 via a transport path 312. In this manner, a color image is formed (printed) on the recording material.

[0025] When further fixing processing is required depending on the type of recording material, the recording material that has passed the fixing unit 311 is guided to a conveying path 314 provided with a fixing unit 313. The fixing unit 313 performs further fixing processing on the recording material conveyed on the conveying path 314. The recording material that has passed the fixing unit 313 is conveyed to a connection point 315. When an operation mode for performing double-sided printing is set, an image is printed on the first side, and the recording material conveyed on the conveying path 312 or the conveying path 314 is guided to a reversing path 316. The recording material that has been reversed on the reversing path 316 is guided to a double-sided conveying path 317 and conveyed to a secondary transfer position 309. As a result, a toner image is transferred to a second side of the recording material that is opposite to the first side at the secondary transfer position 309. Thereafter, the recording material passes through the fixing unit 311 (and the fixing unit 313), completing the formation of a color image on the second side of the recording material.

[0026] When the image formation (printing) in the printing section 107 is completed, the printed recording material that has been transported to the connection point 315 is transported into the diagnosis section .

[0027] The diagnosis unit 108 includes image reading units 331 and 332 each having a contact image sensor (CIS) on a transport path 330 along which the printed recording material from the printing unit 107 is transported. The image reading units 331 and 332 are disposed in positions facing each other across the transport path 330. The image reading units 331 and 332 are configured to read the top surface (first surface) and bottom surface (second surface) of the recording material, respectively. Note that the image reading unit may be configured with a charge coupled device (CCD) or a line scan camera instead of the CIS, for example.

[0028] The diagnosis unit 108 performs an image diagnosis process (image diagnosis) for determining the presence or absence of a defective part in the image forming apparatus 101 based on an image printed on a printed recording material being transported on the transport path 330. Specifically, the diagnosis unit 108 performs a reading process for reading an image of the printed recording material using the image reading units 331 and 332 at the timing when the printed recording material being transported reaches a predetermined position.

[0029] The diagnosis unit 108 is executed based on an instruction from a user to execute image diagnosis processing. The image diagnosis processing is desirably executed, for example, before the start of a printing operation or when printing defects continue. The recording materials that have passed through the diagnosis unit 108 are conveyed to a stacker 109 in order.

[0030] Stacker 109 includes a stack tray 341 as a tray on which printed recording materials transported from diagnostic unit 108 disposed upstream in the transport direction of the printed recording materials are stacked. The printed recording materials that have passed diagnostic unit 108 are transported along transport path 344 in stacker 109. The printed recording materials transported along transport path 344 are guided to transport path 345, whereby the printed recording materials are stacked on stack tray 341.

[0031] The stacker 109 further includes an escape tray 346 as a paper discharge tray. In this embodiment, the escape tray 346 is used to discharge recording material on which a test chart used in image diagnosis by the diagnosis unit 108 is recorded. The printed recording material conveyed along the conveying path 344 is guided to a conveying path 347 and conveyed to the escape tray 346. The printed recording material conveyed in the stacker 109 without being stacked or discharged is conveyed via a conveying path 348 to the finisher 110 at the subsequent stage.

[0032] The stacker 109 further includes an inverting unit 349 for inverting the orientation of the printed recording material being transported. The inverting unit 349 is used, for example, to make the orientation of the recording material input to the stacker 109 the same as the orientation of the printed recording material when it is stacked on the stack tray 341 and output from the stacker 109. Note that the inverting operation by the inverting unit 349 is not performed on the printed recording material that is not stacked in the stacker 109 and is transported to the finisher 110.

[0033] The finisher 110 executes a finishing function designated by a user on the printed recording material conveyed from the diagnosis unit 108 disposed upstream in the conveying direction of the printed recording material. In this embodiment, the finisher 110 has finishing functions such as a staple function (one or two-point binding), a punch function (two or three holes), and a saddle stitch binding function. The finisher 110 includes two paper discharge trays 351 and 352. When the finishing process is not performed by the finisher 110, the printed recording material conveyed to the finisher 110 is discharged to the paper discharge tray 351 through a conveying path 353. When the finishing process such as stapling is performed by the finisher 110, the printed recording material conveyed to the finisher 110 is guided to a conveying path 354. The finisher 110 uses a finishing processing unit 355 to perform a finishing process specified by a user on the printed recording material transported along the transport path 354, and ejects the printed recording material after the finishing process to an ejection tray 352.

[0034] <Functional configuration diagram> FIG. 3 is a schematic functional block diagram of the image forming apparatus 101, the external controller 102, and the client PC 103. As shown in FIG.

[0035] The printing unit 107 of the image forming apparatus 101 includes a communication I / F (interface) 201, a network I / F 204, a video I / F 205, a CPU 206, a memory 207, a HDD unit 208, and a UI display unit 225. The printing unit 107 further includes an image processing unit 202 and a print unit 203. These are connected to each other via a system bus 209 so as to be able to transmit and receive data. The communication I / F 201 is connected to the diagnosis unit 108, the stacker 109, and the finisher 110 via a communication cable 260. The CPU 206 communicates with each device for controlling the devices via the communication I / F 201. The network I / F 204 is connected to the external controller 102 via the internal LAN 105 and is used for communication of control data and the like. The video I / F 205 is connected to the external controller 102 via a video cable 106 and is used for communication of data such as image data and the like. Note that the printing unit 107 (image forming apparatus 101) and the external controller 102 may be connected only by the video cable 106, as long as the external controller 102 can control the operation of the image forming apparatus 101. The HDD unit 208 stores various programs or data. The CPU 206 controls the operation of the entire printing unit 107 by executing the programs stored in the HDD unit 208. The memory 207 stores programs and data required when the CPU 206 performs various processes. The memory 207 operates as a work area for the CPU 206. The UI display unit 225 accepts input of various settings and operation instructions from the user, and is used to display various information such as setting information and the processing status of a print job. For example, it accepts various instructions from the user, such as instructions to execute diagnosis, settings, and paper information settings.

[0036] The diagnosis unit 108 includes a communication I / F 211, a CPU 214, a memory 215, an HDD unit 216, image reading units 331 and 332, and a UI display unit 241. These devices are connected to each other via a system bus 219 so as to be able to transmit and receive data to and from each other. The communication I / F 211 is connected to the printing unit 107 via a communication cable 260. The CPU 214 performs communication required for controlling the diagnosis unit 108 via the communication I / F 211. The CPU 214 controls the operation of the diagnosis unit 108 by executing a control program stored in the memory 215. The memory 215 stores a control program for the diagnosis unit 108. The image reading units 331 and 332 read images of the conveyed recording material in accordance with an instruction from the CPU 214. The CPU 214 diagnoses the presence or absence of a defective portion of the image forming apparatus 101 based on the diagnostic read images read by the image reading units 331 and 332. The UI display unit 241 is used to display the diagnosis results, the setting screen, etc. The operation unit also serves as the UI display unit 241 and is operated by the user to receive various instructions from the user, such as changing the settings of the diagnosis unit 108 and instructions to execute image diagnosis. The HDD unit 216 stores various setting information and image data required for image diagnosis. The various setting information and image data stored in the HDD unit 216 can be reused.

[0037] The stacker 109 controls the printed recording material transported along the transport path so that it is discharged to a stack tray, discharged to an escape tray, or transported to a finisher 110 connected downstream in the transport direction of the printed recording material.

[0038] The finisher 110 controls the transport and discharge of printed recording materials, and performs finishing processes such as stapling, punching, or saddle stitching.

[0039] The external controller 102 includes a CPU 251, a memory 252, an HDD unit 253, a keyboard 256, a display unit 254, network I / Fs 255 and 257, and a video I / F 258. These devices are connected to each other via a system bus 259 so as to be able to transmit and receive data to each other. The CPU 251 executes a program stored in the HDD unit 253 to control the overall operation of the external controller 102, such as receiving print data from the client PC 103, RIP processing, and transmitting print data to the image forming apparatus 101. The memory 252 stores programs and data required for the CPU 251 to perform various processes. The memory 252 operates as a work area for the CPU 251.

[0040] The HDD unit 253 stores various programs and data. The keyboard 256 is used for inputting operation instructions for the external controller 102 from the user. The display unit 254 is, for example, a display, and is used for displaying information on applications being executed in the external controller 102 and an operation screen. The network I / F 255 is connected to the client PC 103 via the external LAN 104 and is used for communication of data such as print instructions. The network I / F 257 is connected to the image forming apparatus 101 via the internal LAN 105 and is used for communication of data such as print instructions. The external controller 102 is configured to be able to communicate with the printing unit 107, the diagnosis unit 108, the stacker 109, and the finisher 110 via the internal LAN 105 and a communication cable 260. The video I / F 258 is connected to the image forming apparatus 101 via the video cable 106 and is used for communication of data such as image data (print data).

[0041] The client PC 103 includes a CPU 261, a memory 262, an HDD unit 263, a display unit 264, a keyboard 265, and a network I / F 266. These devices are connected via a system bus 269 so as to be able to transmit and receive data to and from each other. The CPU 261 controls the operation of each device via the system bus 269 by executing a program stored in the HDD unit 263. This allows the client PC 103 to perform various processes. For example, the CPU 261 generates print data and issues a print instruction by executing a document processing program stored in the HDD unit 263. The memory 262 stores programs and data required when the CPU 261 performs various processes. The memory 262 operates as a work area for the CPU 261.

[0042] The HDD unit 263 stores various applications such as a word processing program, programs such as a printer driver, and various data. The display unit 264 is, for example, a display, and is used to display information about applications running on the client PC 103 and an operation screen. The keyboard 265 is used to input operation instructions for the client PC 103 from a user. The network I / F 266 is communicably connected to the external controller 102 via the external LAN 104. The CPU 261 communicates with the external controller 102 via the network I / F 266.

[0043] <Image diagnosis processing> The image diagnosis processing according to this embodiment will be described with reference to the drawings. FIG. 4 is a flowchart showing the print operation executed by the printing unit 107 and the procedure of the image diagnosis processing executed by the diagnosis unit 108. Note that FIG. 4 shows the overall flow from the work before the start of image diagnosis to the execution of diagnosis. The symbol "S" in the explanation of the flowchart represents a step. This also applies to the explanation of the following flowcharts. The processing of each step in FIG. 4 is executed by the CPU 206 of the printing unit 107 and the CPU 214 of the diagnosis unit 108.

[0044] In S401, the printing system 100 accepts an instruction for image diagnosis from a user or a serviceman via the UI display unit 241, which also serves as an operation unit, and checks the settings of the image diagnosis process. In this embodiment, the timing for starting the image diagnosis process is, for example, after starting up the main body by turning on the power. After starting up, a notification prompting the start of diagnosis is displayed on one or more of the UI display unit 241, the display unit 254 of the external controller 102, and the UI display unit 225 of the printing unit 107, and an instruction to start diagnosis is prompted. In addition, the start timing of the image diagnosis process is not limited to the above example. In the case where an inspection function for inspecting the presence or absence of printing defects on printed recording material is also provided, if defects are continuously found by the inspection function, the start of the image diagnosis process may be prompted. Furthermore, a configuration may be adopted in which a timer is set to a time for displaying a notification prompting the execution of the image diagnosis process other than when the main body is started, and the notification is displayed at the set time.

[0045] When the user confirms the notification prompting the start of diagnosis, the CPU 214 displays a screen for accepting the user's selection of diagnostic conditions on the UI display unit 241, accepts the user's selection of diagnostic conditions, and stores the accepted diagnostic conditions in the HDD 216. FIG. 5 is a schematic diagram of the screen for accepting the user's diagnostic conditions. The user is prompted to select the shape of the defect to be diagnosed and the color material to be diagnosed for each defect shape as diagnostic items. As shown in FIG. 5, a check box is provided for each condition, and the conditions that are checked when the user presses the Next button 501 are stored in the HDD 216 as diagnostic conditions. Once the diagnostic conditions are stored, the process proceeds to step S402, where the next paper feed deck is selected.

[0046] In S402, the CPU 251 of the external controller 102 accepts the selection of a paper feed deck in which paper for printing a diagnostic test chart (diagnostic image) is stored. The CPU 251 displays on the UI display unit 241 a screen for accepting the selection of the position of a paper feed deck mounted in the image forming apparatus 101. The user selects the deck position in which paper for printing a test chart is stored from among the paper feed decks mounted in the image forming apparatus 101.

[0047] In S403, the CPU 251 of the external controller 102 performs a calculation process for the number of test charts required for image diagnosis. In the calculation process for the number of test charts, the number of test charts to be output in the test chart printing process in S406 is calculated based on the image diagnosis conditions. The details of the calculation process for the number of test charts required for image diagnosis will be described later.

[0048] In S404, the CPU 251 of the external controller 102 notifies the number of test charts. The number of test charts is notified by, for example, displaying a screen as shown in Fig. 6 on the UI display unit 241 and controlling the display of the number of test charts (output number) calculated in S403 in 601. Thereafter, the process proceeds to S405, where an instruction to start or cancel image diagnosis is accepted. This process allows the user to check the number of test charts to be output before the output of the test charts for image diagnosis starts.

[0049] In S405, the CPU 214 accepts an instruction to start or cancel image diagnosis. An instruction to start image diagnosis is, for example, pressing the button 602 shown in Fig. 6. If an instruction to start image diagnosis is accepted (YES in S405), the process proceeds to S406, where printing of a test chart is started. An instruction to cancel is, for example, pressing the button 603 shown in Fig. 6. If an instruction to cancel is accepted (NO in S405), the process proceeds to S419, where a response is displayed and image diagnosis processing is terminated.

[0050] In S406, the CPU 251 of the external controller 102 reads out the test chart stored in advance, rasterizes it into a bitmap, and creates the rasterized bitmap of the test chart as a reference image. The test chart is an image for diagnosing a fault in the image forming apparatus (hereinafter, also referred to as a test image). FIG. 10 is a diagram showing an example of a test chart used in the image diagnosis process in this embodiment. An image section 1001 shows an area where an image is formed by a color material. For example, the image section uses a single-color image with an area ratio of 50%, and prints a total of four types of test charts, one type each of C (cyan), M (magenta), Y (yellow), and K (black), for the number of sheets calculated in S403. The CPU 251 transmits the bitmap data of the rasterized test chart from the video I / F 258 to the video I / F 205 of the printing section 107 through the video cable 106. The CPU 206 of the printing unit 107 performs halftone processing on the bitmap data of the test chart received by the video I / F 205, and the print unit 203 prints the test chart based on the image data after the halftone processing. Note that the configuration of the test chart is an example, and is not limited to the above example. As long as the conditions are such that defects in the printed part are made apparent by a difference image, which will be described later, the ratio or area ratio of the image part to the non-image part may be different, and the image part may use two or more color materials.

[0051] In S407, the CPU 214 of the diagnosis unit 108 executes a process of reading the printed test chart using the image reading units 331 and 332. The read image of the test chart is stored as a diagnostic image in the HDD unit 216 of the diagnosis unit 108. After the diagnostic image is stored, the process proceeds to S408.

[0052] In S408, the CPU 214 compares the reference image with the read image to determine defects in the printing unit. In this embodiment, the reference image is compared with the read image to calculate a difference value. If the calculated difference value exceeds a preset threshold value, it is determined that there is a difference, and 1 is set to the difference image data. Conversely, if it is below the threshold value, 0 is set to the difference image data. Note that the calculation method of the difference image data is not limited to the above example. In this embodiment, an example is described in which the reference image is compared with the read image to calculate a difference value, but an average value may be calculated from the read image to calculate the difference value as a reference signal, or a value assumed as a reference signal may be stored in the HDD unit 216 in advance. In addition, a correction unit that corrects the nonlinearity between the signal value and brightness of the read image acquired by the image reading unit 311 may be provided, and the signal value of the read image may be corrected before the calculation of the difference image data. The difference image data, which is binary data indicating the presence or absence of a difference, is stored in the HDD unit 216, and the process proceeds to S409.

[0053] When the creation of the differential image data is completed, in S409, the CPU 214 judges whether the image forming apparatus 101 is normal. The judgment is made based on whether data including 1 exists in the differential image data. When the CPU 214 obtains a judgment result that the image forming apparatus 101 is normal (YES in S409), the process proceeds to S417. In S417, the CPU 214 displays the diagnosis result "No problem" indicating that the diagnosis result is normal on the UI display unit 241 of the diagnosis unit 108. On the other hand, when the CPU 214 obtains a judgment result that the image forming apparatus 101 is not normal (the differential image data includes 1) (NO in S409), the process proceeds to S410. In the process from S410, a part in the image forming apparatus 101 where a malfunction is occurring is identified based on the read image data and the differential image data, and a countermeasure is instructed.

[0054] In S410, the CPU 214 extracts a feature amount for identifying a defective part in the printing unit 107 from the read image data and the difference image data. The feature of the difference is extracted from the read image corresponding to the difference area determined to have a difference calculated from the difference image data in S408. The feature information of the difference area obtained by this extraction process includes color material information indicating which color, yellow, magenta, cyan, or black, the defect occurs in. Further, the feature information of the difference area includes contrast information indicating the difference in the dark direction (positive direction) or the light direction (negative direction) of the defect density contrast as a positive or negative numerical value. Further, the feature information of the difference area includes size information such as the width (size in the main scanning direction) and height (size in the sub-scanning direction) of the defect, and shape information such as the shape of a dot, vertical streak, or horizontal streak. Further, the feature information of the difference area includes coordinate information indicating the position in a direction perpendicular to the transport direction of the test chart in the printing unit 107, and periodic information indicating that defects with similar characteristics occur periodically in the transport direction of the test chart in the printing unit 107. The extracted features are stored in the HDD unit 216, and the process proceeds to S411.

[0055] In S411, based on the characteristic information of the differential region obtained in S410, the CPU 214 identifies the part (site) that is the cause of the image defect in the printing unit 107 and the image reading unit 331. From the differential regions, a combination of the same color with high similarity is selected, and which part is defective is identified from the periodic information of the selected combination.

[0056] In S412, the CPU 214 determines how to deal with the image defect based on the part that is the cause identified in S411. The measures are divided into measures that can be automatically restored and measures that cannot be automatically restored. The measures that can be automatically restored include measures that can be automatically restored by the printing unit 107, such as cleaning the wires and grids of the corona chargers that are charging means for the photosensitive drums provided in the image forming stations 304 to 307 of the printing unit 107. The measures that cannot be automatically restored include the following two examples. First, measures that require user work, such as cleaning dirt from the reading glass surfaces of the image reading units 331 and 332 of the diagnosis unit 108 and adjusting the recording material to be used, and measures that require service personnel work, such as replacing parts. Second, measures that require, for example, reading abnormalities of the image reading unit, and measures against fibers and foreign matter that are in the recording material before image formation.

[0057] Next, in S413, the CPU 214 determines whether or not the action determined in S412 is an automatically recoverable action. If the CPU 214 obtains a determination result that the action determined in S412 is an automatically recoverable action (YES in S413), the process proceeds to S414.

[0058] In S414, the CPU 251 of the external controller 102 performs a calculation process for the number of test charts (repair images) required for automatic return (automatic repair). In the calculation process for the number of test charts, the number of test charts to be output in the automatic return process in S418 is calculated based on the automatic return conditions. The details of the calculation process for the number of test charts will be described later.

[0059] In S415, the CPU 251 of the external controller 102 notifies the user of the number of test charts required for automatic return. The number of test charts is notified by, for example, displaying a screen as shown in Fig. 7 on the UI display unit 241 and displaying the number of test charts calculated in S414 in 701. Thereafter, the process proceeds to S416, where an instruction to start or cancel automatic return is accepted. This process allows the user to check the number of test charts to be output before the output of the test charts for automatic return starts.

[0060] In S416, the CPU 214 accepts an instruction to start automatic return or to cancel. An instruction to start automatic return is, for example, pressing the button 702 shown in Fig. 7. If an instruction to start image diagnosis is accepted (YES in S416), the process proceeds to S418, where printing of a test chart is started. An instruction to cancel is, for example, pressing the button 703 shown in Fig. 7. If an instruction to cancel is accepted (NO in S416), the process proceeds to S419, where a response is displayed and image diagnosis processing is terminated.

[0061] In S418, the CPU 214 executes automatic recovery control to deal with the cause of the image defect.

[0062] On the other hand, when the CPU 214 obtains a determination result that the determined action is not an action that can be automatically restored (NO in S413), the process proceeds to S419. In S419, the CPU 214 displays the image diagnosis result and the method of action on the UI display unit 241 of the diagnosis unit 108. When any one of the above-mentioned processes of S417, S418, and S419 is completed, the flow (image diagnosis process) shown in FIG. 4 is terminated.

[0063] <Calculating the number of test charts required for image diagnosis> In S403, the number of test charts required for image diagnosis is calculated according to the diagnosis conditions. In this embodiment, the diagnosis conditions are diagnosis item information, diagnosis color information, paper size information, and model information. In this embodiment, the designation of defect shape is accepted as the diagnosis item. There are three types of defect shapes: vertical streaks, horizontal streaks, and dots. In the diagnosis of vertical streaks, defects on the streaks in the sub-scanning direction are diagnosed and the part causing the defect is identified. Since there is no need to look at periodicity, one chart is sufficient for one diagnosis color. On the other hand, in the diagnosis of horizontal streaks and dots, multiple charts may need to be output in order to determine periodicity. The number of sheets required to determine periodicity varies depending on the part cycle of the image forming device and also varies depending on the length of the paper used in the sub-scanning direction.

[0064] Therefore, the number of sheets is determined by referring to a table of diagnostic conditions stored in advance. FIG. 8 is a schematic diagram of a table for determining the required number of sheets from diagnostic item information, diagnostic color information, paper size information, and model information. For example, in the case of a diagnostic condition for diagnosing horizontal streaks in C (cyan) using A4 paper in model A, the number of sheets 801 is referred to and the required number of sheets is determined to be 15. When multiple conditions are ON, the number of sheets determined for each condition is summed up. For example, in the case of a diagnostic condition for diagnosing horizontal streaks in C (cyan) and K (black) using A4 paper in model A, the number of sheets 801 and the number of sheets 802 are referred to and summed up, and the required number of sheets is determined to be 30. On the other hand, even if the conditions are different, if the same chart is used and only the number of sheets is different, the sum is not calculated and the larger number is selected as the required number. For example, in model A, when the diagnostic conditions are to diagnose vertical streaks and dots in C (cyan) using A4 paper, the number of sheets required for vertical streaks is 1 sheet (803), and the number of sheets required for dots is 15 sheets (804). If the charts used in these diagnostics are the same and only the number of sheets differs, the required number is determined to be the greater number, which is 15 sheets. In this case, the first sheet of the chart to be output is used for the vertical streak diagnosis, and the first through fifteenth sheets are used for the dot diagnosis.

[0065] The method of setting diagnostic conditions is not limited to referring to a table, and any method that can calculate the required number may be used. For example, a method of calculating the number of parts by storing parts information for each model in advance may be used.

[0066] In addition, in this embodiment, an example is described in which the shape of the defect is specified as a diagnosis item, but the part to be diagnosed may be selected. For example, parts to be diagnosed such as "photosensitive drum" and "intermediate transfer belt" are displayed on the UI as diagnosis items, and the number of charts required for diagnosis is calculated and displayed according to the part selected by the user.

[0067] <Calculation of the number of test charts required for automatic recovery> In S414, the number of test charts required for automatic recovery is calculated according to the recovery conditions. In this embodiment, the recovery conditions are the automatic recovery item information, the paper size information, and the model information. In this embodiment, the determination result obtained in S412 that the automatic recovery is possible is accepted as the automatic recovery item. The number of test charts required for automatic recovery varies depending on the automatic recovery item information, the paper size information, and the model information. For example, when the cause of the dots is the photosensitive drum and recovery is performed by idling the photosensitive drum, a test chart is output to confirm that the dots have disappeared by recovery. The number of sheets required to confirm that the periodically occurring defects have disappeared varies depending on the part cycle of the image forming apparatus and also varies depending on the length of the paper used in the sub-scanning direction. In addition, depending on the automatic recovery item, a test chart may be required not only for confirmation but also for adjustment for recovery.

[0068] Therefore, the number of sheets is determined by referring to a table of recovery conditions stored in advance. FIG. 9 is a schematic diagram of a table for determining the required number of sheets from automatic recovery item information, paper size information, and model information. For example, in the case of automatic recovery using A4 paper and performing secondary transfer current adjustment in model A, the number of sheets 901 and the number of sheets 902 are referred to, and the number of sheets used for adjustment and the number of sheets used for confirmation are summed up to determine the required number of sheets as 3. When multiple conditions are ON, the number of sheets determined for each condition is summed up. For example, in the case of recovery using A4 paper in model A and performing secondary transfer current adjustment and drum idling rotation, 901, 902, 903, and 904 are respectively referred to, and the sum is determined to be 5. In addition, when performing a retry when recovery is not successful in the confirmation of the automatic recovery process, the required number may be determined by taking into consideration the maximum number of retries. For example, when the maximum number of retries is 3, the required number is multiplied by 3.

[0069] The method of setting the restoration conditions is not limited to referring to a table, and any method that can calculate the required number may be used. For example, a method of calculating the number of parts by storing parts information for each model in advance may be used.

[0070] As described above, an example has been described in which the number of charts is determined according to diagnostic conditions and the number of sheets of paper to be used in image diagnosis is notified to the user. By notifying the user, it is possible to prevent unintended paper consumption by the user.

[0071] <Modification of the first embodiment> In this embodiment, an example has been described in which, after accepting the selection of diagnostic conditions by the user on the diagnostic condition selection screen illustrated in FIG. 5, the screen illustrated in FIG. 6 is displayed when the button 501 is pressed to notify the user of the number of sheets of paper to be used in the image diagnosis. However, this embodiment is not limited to the above example. For example, instead of displaying the notification screen as illustrated in FIG. 6, the number of sheets of paper to be used in the image diagnosis may be displayed and notified on the diagnostic condition selection screen as illustrated in FIG. 11. Depending on the selection state of diagnostic items by the user, the number of test charts required for the image diagnosis described above is calculated sequentially and displayed in 1101. Also, as illustrated in 1102, the number of test charts required for each diagnostic item and diagnostic color may be displayed in a selection field.

[0072] In this embodiment, the number of test charts required for image diagnosis and the number of test charts required for automatic recovery are calculated after the diagnosis conditions and the recovery conditions are determined, but the present invention is not limited to the above example. For example, in a configuration in which a cassette is selected after the number of test charts required for image diagnosis is notified, the paper size is not yet determined at the time of performing the calculation process for the number of test charts required for image diagnosis. Therefore, in the diagnosis of horizontal streaks C of model A, the range of 8 to 15 sheets can be taken, but in this case, the possible range may be notified as shown in 601 in FIG. 12.

[0073] In this embodiment, the calculated number of test charts required for image diagnosis and the number of test charts required for automatic return are displayed to notify the user, but the effect of this embodiment is not limited to the above example. For example, if the number of sheets of paper in the cassette selected in S402 is less than the calculated number of test charts required for image diagnosis, a warning message may be displayed as shown in FIG. 13 to prompt the user to replenish the sheets of paper.

[0074] In this embodiment, the calculated number of test charts required for image diagnosis and the calculated number of test charts required for automatic return are always notified, but the effect of this embodiment is not limited to the above example. For example, the notification of the number of test charts in S404 and the notification of the number of test charts in S415 may be performed only when the number of test charts exceeds a predetermined number.

[0075] [Second embodiment] The image diagnosis processing according to the present embodiment will be described. In the first embodiment, an example was described in which, when performing image diagnosis processing, diagnostic items and diagnostic colors determined by user selection are received and the number of test charts is calculated. However, the effect of the present embodiment is not limited to the above example. For example, a configuration may be adopted in which diagnostic items and diagnostic colors are automatically determined by performing simple image diagnosis with a smaller number of test charts before performing image diagnosis.

[0076] 14 is a flowchart showing a print operation executed by the printing unit 107 and a procedure of simple image diagnosis processing executed by the diagnosis unit 108. The processing of each step in FIG. 14 is executed by the CPU 206 of the printing unit 107 and the CPU 214 of the diagnosis unit 108.

[0077] In S1401, the printing system 100 accepts an image diagnosis instruction from a user or a serviceman via the UI display unit 241, which also serves as an operation unit. After that, the CPU 251 of the external controller 102 reads out a test chart stored in advance, rasterizes it into a bitmap, and creates the rasterized bitmap of the test chart as a reference image. The test chart is an image for fault diagnosis of an image forming apparatus (hereinafter, also referred to as a test image). FIG. 9 is a diagram showing an example of a test chart used in the image diagnosis process in this embodiment. The image section 901 shows an area where an image is formed by a color material. For example, the image section uses a single-color image with an area ratio of 50%, and prints one sheet each of four types of test charts, one type for each single color in CMYK. The CPU 251 transmits the bitmap data of the rasterized test chart from the video I / F 258 to the video I / F 205 of the printing unit 107 through the video cable 106. The CPU 206 of the printing unit 107 performs halftone processing on the bitmap data of the test chart received by the video I / F 205, and the print unit 203 prints the test chart based on the image data after halftone processing. Note that the configuration of the test chart is an example, and is not limited to the above example. As long as the condition is such that defects in the printed portion are made apparent by a difference image, which will be described later, the ratio or area ratio of the image portion to the non-image portion may be different, and the image portion may use two or more color materials. Also, multiple image portions using different color materials may be provided on one sheet.

[0078] In S1402, the CPU 214 determines diagnostic items and diagnostic colors that require image diagnosis based on the characteristic information of the difference region obtained in S410. The diagnostic items and diagnostic colors that require image diagnosis are determined according to color material information on which color (yellow, magenta, cyan, or black) is generated and shape information such as dot shape, vertical stripe shape, and horizontal stripe shape extracted in S410. For example, when a yellow vertical stripe is extracted, the diagnostic item and diagnostic color of the vertical stripe Y are turned ON to start image diagnosis processing. When a yellow vertical stripe and a magenta vertical stripe are extracted, the diagnostic items and diagnostic colors of the vertical stripe Y and M are turned ON to start image diagnosis processing. Also, when a yellow vertical stripe and a magenta dot are extracted, the diagnostic item and diagnostic color of the vertical stripe Y and the dot M are turned ON to start image diagnosis processing.

[0079] 4 in the first embodiment, the number of test charts required for the image diagnosis is calculated based on the diagnosis items and diagnostic colors determined in S1402 in S403, and the number of test charts is notified in S404. This makes it possible to notify the user of the number of sheets of paper to be used in the image diagnosis and prevent unintended paper consumption by the user, even in a configuration in which diagnosis items and diagnostic colors are automatically determined by performing simple image diagnosis.

[0080] <Other embodiments> The present invention can also be realized by a process in which a program for implementing one or more of the functions of the above-described embodiments is supplied to a system or device via a network or a storage medium, and one or more processors in a computer of the system or device read and execute the program. The present invention can also be realized by a circuit (e.g., ASIC) that implements one or more of the functions.

Claims

1. An operation unit for displaying information; an image forming unit that forms an image on a sheet and that is composed of a plurality of parts; a reading unit that reads the image formed by the image forming unit; A display control means for causing the operation unit to display a screen for receiving instructions for image diagnosis; a diagnostic unit that, in response to an instruction to start image diagnosis received by the operation unit, causes the image forming unit to form a diagnostic image on paper, causes the reader unit to read the formed and output diagnostic image, and diagnoses a defective portion of the image forming unit based on the read image, The image diagnostic system, wherein the screen includes the number of output sheets of the diagnostic images.

2. The image diagnostic system according to claim 1 , wherein the number of sheets to be output is determined based on a diagnostic item of the image diagnosis.

3. The image diagnostic system according to claim 1 , wherein the number of sheets to be output is determined based on a model of the device that performs the image diagnosis.

4. The image diagnostic system according to claim 1 , wherein the number of output sheets is determined based on the size of paper on which the diagnostic images are formed.

5. a repair unit that causes the image forming unit to form a repair image on a sheet, causes the reading unit to read the formed and output repair image, and repairs a defective portion identified by the diagnosis by the diagnosis unit based on the read image, 2. The image diagnostic system according to claim 1, wherein the screen includes the number of the images to be output for repair.

6. 6. The image diagnostic system according to claim 5, wherein, when a defective portion of the image forming unit is identified as a result of diagnosis by the diagnosis means, repair is performed by the repair means.

7. 2. The image diagnostic system according to claim 1, wherein the diagnostic items determined by said diagnostic means are one or more of vertical streaks, horizontal streaks, and dots.

8. a display control step of displaying a screen for receiving an instruction for image diagnosis on an operation unit; a diagnostic step of, in response to an instruction to start image diagnosis received by the operation unit, causing an image forming unit to form a diagnostic image on paper, causing a reading unit to read the formed and output diagnostic image, and diagnosing a defective portion of the image forming unit based on the read image; The image diagnostic method according to the present invention, wherein the screen includes the number of diagnostic images to be output.

9. The image diagnostic method according to claim 8 , wherein the number of output sheets is determined based on a diagnostic item of the image diagnosis.

10. The image diagnosis method according to claim 8 , wherein the number of sheets to be output is determined based on a model of the device that performs the image diagnosis.

11. 9. The image diagnostic method according to claim 8, wherein the number of output sheets is determined based on the size of paper on which the diagnostic images are formed.

12. a repair step of causing the image forming unit to form a repair image on a sheet, causing the reading unit to read the formed and output repair image, and repairing a defective portion identified by the diagnosis in the diagnosis step based on the read image, 9. The image diagnostic method according to claim 8, wherein the screen includes the number of the restoration images to be output.

13. 13. The image diagnostic method according to claim 12, wherein, when a defective portion of the image forming unit is identified as a result of diagnosis by the diagnosing means, repair is performed by the repairing step.

14. 9. The image diagnostic method according to claim 8, wherein the diagnostic items in said diagnosing step are one or more of vertical streaks, horizontal streaks, and dots.

Images