Diagnostic device, diagnostic system and program

Abstract

To enable an image formation apparatus to be diagnosed more easily than a conventional technique by using an imaging device.SOLUTION: An imaging device acquires size information indicating the size of a sheet and transmits an instruction for causing an image formation apparatus to form an image for diagnosis on a sheet. The imaging device acquires a sheet image by imaging the sheet formed with the image for diagnosis. The imaging device executes diagnosis of a component of the image formation apparatus on the basis of the size information and the occurrence position of an image defect in the sheet image and outputs a diagnosis result.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a diagnostic device, a diagnostic system, and a program for diagnosing an image forming apparatus. [Background technology]

[0002] When components of an image forming device reach the end of their useful life, defects may occur in the image. Patent Document 1 describes how an image on a sheet is read by an image sensor built into the image forming device to identify the component causing the image defect. Patent Document 2 describes how an image on a sheet is captured by an imaging device such as a digital camera or a camera-equipped mobile phone, and calibration of the image forming device is performed based on the captured image. The calibration in Patent Document 2 refers to updating a gamma correction table that corrects the gradation of an image. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5164458 [Patent Document 2] Patent No. 6350474 Summary of the Invention [Problem to be solved by the invention]

[0004] According to the invention of Patent Document 1, an image forming device that does not have an image sensor cannot identify the component that is causing the image defect. In this case, the user must purchase an image forming device that has an image sensor. The invention of Patent Document 2 cannot detect the image defect in the first place, nor can it identify the component that is causing the image defect. Therefore, the object of the present invention is to use an imaging device to make it easier to diagnose the image forming device than before. [Means for solving the problem]

[0005] The present invention relates to, for example, an image forming device for forming a diagnostic image on a sheet; a diagnostic image formed by the image forming apparatus; and an imaging apparatus for imaging a sheet discharged from the image forming apparatus and outputting a sheet image, The imaging device includes: An acquisition means for acquiring size information indicating a size of the sheet; a diagnostic unit for diagnosing components of the image forming apparatus based on the size information and the position of the image defect in the sheet image; an output means for outputting a diagnosis result of the diagnosis means; A diagnostic system is provided comprising: Effect of the Invention

[0006] According to the present invention, by using an imaging device, it becomes possible to diagnose an image forming apparatus more easily than in the past. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram illustrating a diagnostic system. [Diagram 2] FIG. 1 is a diagram illustrating an imaging apparatus. [Diagram 3] FIG. 1 is a diagram illustrating an image forming apparatus. [Figure 4] FIG. 3 is a diagram illustrating a paper feed cassette. [Diagram 5] FIG. 2 is a diagram illustrating a control unit of the server and the image forming apparatus. [Figure 6] 1 is a flowchart showing an image diagnosis method, etc. [Figure 7] 4A and 4B are diagrams for explaining a diagnostic image and a sheet image. [Figure 8] 5A to 5C are diagrams illustrating a method of correcting an image. [Figure 9] 11A to 11C are diagrams for explaining the effects of the embodiment. [Figure 10] 1A and 1B are diagrams for explaining an image diagnostic method using a plurality of sheets. [Figure 11]11 is a flowchart showing other image diagnosis methods, etc. [Figure 12] 13 is a flowchart showing yet another image diagnosis method. [Figure 13] A diagram explaining the functions of a CPU. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, the embodiments will be described in detail with reference to the attached drawings. Note that the following embodiments do not limit the invention according to the claims. Although the embodiments describe a number of features, not all of these features are essential to the invention, and the features may be combined in any manner. Furthermore, in the attached drawings, the same reference numbers are used for the same or similar configurations, and duplicated descriptions are omitted.

[0009] <Example 1> [Diagnostic system] As shown in FIG. 1, the diagnostic system 100 includes an image forming apparatus 101 to be diagnosed and an imaging apparatus 102. A server 103 is optional. It is assumed here that the image forming apparatus 101 does not include an image sensor for reading a diagnostic image formed on a sheet. However, the image forming apparatus 101 may include an image sensor for reading a diagnostic image formed on a sheet. For example, there are cases where the diagnostic function of the imaging apparatus 102 is superior to the diagnostic function of the image forming apparatus 101. In this case, a user would want to diagnose the image forming apparatus 101 using the imaging apparatus 102.

[0010] The imaging device 102 has a camera (photographing device) and is a communication device (e.g., a smartphone, a tablet terminal, a digital camera) that can be carried by a user. Here, the user is a person who can operate the imaging device 102, and includes the owner, user, and maintenance worker of the image forming device 101. The imaging device 102 has a wireless communication circuit (e.g., wireless LAN, Bluetooth (registered trademark), cellular wireless) and a wired communication circuit (e.g., a USB interface), and can communicate with the image forming device 101 and the server 103.

[0011] In the first embodiment, the imaging device 102 functions as a diagnostic device that diagnoses the image forming device 101. The imaging device 102 may capture a diagnostic image formed on a sheet to generate a sheet image and transfer the sheet image to the server 103. The server 103 may diagnose the image forming device 101 based on the sheet image. The server 103 may be a personal computer (PC).

[0012] [Imaging device] FIG. 2 shows the configuration of the imaging device 102. The control unit 201 controls the interface unit 202, the camera 203, the communication unit 204, and the memory unit 205 according to a control program stored in the memory unit 205. The control unit 201 includes hardware circuits such as a CPU (Central Processing Unit), an ASIC (Application Specific Integrated Circuit), and an FPGA (Field Programmable Gate Array). The interface unit 202 has an output device (e.g., a display device, an audio output device) that outputs information to a user, and an input device (e.g., a touch panel) that accepts user input. The camera 203 has an image sensor (e.g., a CMOS image sensor, a CCD image sensor), a light source that irradiates illumination light, and the like. The communication unit 204 has the wireless communication circuit and wired communication circuit described above. The memory unit 205 has a RAM (Random Access Memory), a ROM (Read Only Memory), and the like. The memory unit 205 stores in its ROM area a control program (e.g., diagnostic program 206) and control data (e.g., diagnostic image data 207) executed by the control unit 201. The diagnostic image data 207 is image data that is the source of a diagnostic image formed on a sheet. The memory unit 205 stores in its RAM area a sheet image 208 acquired by the camera 203, a diagnosis result 209, and a collection of case studies 210. The collection of case studies 210 is a data group that links the characteristics of an image defect with a causative part. The control unit 201 identifies the causative part by referring to the collection of case studies 210 based on the characteristics of the detected image defect.

[0013] [Image forming device] 3 shows an electrophotographic image forming apparatus 101, the technical concept of this embodiment can be similarly applied to any image forming apparatus in which components such as a rotating body are involved in forming an image. For example, the technical concept of this embodiment can be applied to an image forming apparatus in which image defects occur in an image formed on a sheet P due to components reaching the end of their designed useful life or due to component failure. Alternatively, the technical concept of this embodiment can be applied to an image forming apparatus in which image defects occur when components that require periodic maintenance (cleaning, adjustment, and replacement) are not regularly maintained.

[0014] 3, the letters Y, M, C, and K added to the end of the reference numerals indicate the toner colors, such as yellow, magenta, cyan, and black. For example, a component having a reference numeral with a suffix Y is involved in forming a yellow toner image. When it is not necessary to distinguish colors in the description of the components, reference numerals without the suffix letter are used.

[0015] The control unit 40 is a control circuit (e.g., a CPU, an ASIC, and an FPGA) that controls each part of the image forming apparatus 101. The control unit 40 receives image data and a print instruction from an external device (e.g., the imaging device 102) via the communication unit 41. The control unit 40 converts the image data to generate an image signal, and supplies the image signal to the exposure device 7.

[0016] The photoconductor 1 is driven by a driving source such as a motor to rotate clockwise, and is an image carrier that carries an electrostatic latent image and a toner image. The photoconductor 1 is also called a photoconductor drum because it is a cylindrical rotating body. The charging roller 2 is applied with a charging bias voltage by the control unit 40, and charges the surface of the photoconductor 1 to a uniform potential. The exposure device 7 irradiates the photoconductor 1 with laser light according to an image signal, and forms an electrostatic latent image on the surface (peripheral surface) of the photoconductor 1. The developing roller 3 is applied with a developing bias voltage by the control unit 40, and adheres toner to the electrostatic latent image to form a toner image on the surface of the photoconductor 1. The primary transfer roller 6 is applied with a primary transfer bias voltage by the control unit 40, and transfers the toner image from the photoconductor 1 to the intermediate transfer belt 8. The drum cleaner 4 is a member that removes and collects toner that is not transferred to the intermediate transfer belt 8 and remains on the photoconductor 1. The photoconductor 1, the developing roller 3, the charging roller 2, and the drum cleaner 4 may be integrated into a cartridge. Such a cartridge is configured to be detachable from the main body of the image forming apparatus 101. The photoconductor 1, the charging roller 2, the exposure device 7, the developing roller 3, and the primary transfer roller 6 function as an image forming unit that forms an image on the intermediate transfer belt 8.

[0017] The intermediate transfer belt 8 is an endless belt, and is sometimes called an intermediate transfer body. The intermediate transfer belt 8 is driven by a drive source such as a motor to rotate counterclockwise. The toner images from the four photoconductors 1 are transferred onto the intermediate transfer belt 8 in a superimposed manner, forming a full-color toner image on the intermediate transfer belt 8. The toner images transferred onto the intermediate transfer belt 8 are transported to a secondary transfer section. The secondary transfer section is a nip section formed by the intermediate transfer belt 8 and a secondary transfer roller 11.

[0018] The image forming apparatus 101 has an upper sheet feed cassette 13a and a lower sheet feed cassette 13b, which are sheet feed trays for feeding sheets. In FIG. 3, the suffix "a" of the reference symbol indicates that the reference symbol is related to the upper sheet feed cassette 13a. The suffix "b" of the reference symbol indicates that the reference symbol is related to the lower sheet feed cassette 13b. When matters common to the upper sheet feed cassette 13a and the lower sheet feed cassette 13b are described, the suffixes "a" and "b" of the reference symbols are omitted. The sheet feed cassette 13 is a storage container that stores a large number of sheets P. The sheet feed roller 14 sends the sheet P from the sheet feed cassette 13 to the conveying path 15 in accordance with an instruction from the control unit 40. The sheet P is conveyed to the secondary transfer unit by conveying rollers 16 and 18 provided along the conveying path 15. The conveying roller 18 is sometimes called a registration roller. A sheet sensor 23 may be provided downstream of the conveying roller 18 in the conveying direction of the sheet P. The sheet sensor 23 is a sensor that detects the presence or absence of a sheet P. The sheet sensor 23 is also called a top sensor because it can detect the arrival of the leading edge (upper end) of the sheet P.

[0019] For convenience of explanation, it is assumed that A4 size sheets Pa are stored in the upper paper feed cassette 13a. It is assumed that B5 size sheets Pb are stored in the lower paper feed cassette 13b. The long sides of the A4 size sheets Pa and the long sides of the B5 size sheets Pb are parallel to the conveying direction. In other words, the short sides of the A4 size sheets Pa and the short sides of the B5 size sheets Pb are perpendicular to the conveying direction.

[0020] A secondary transfer bias voltage is applied to the secondary transfer roller 11 by the control unit 40, and the secondary transfer roller 11 transfers the toner image from the intermediate transfer belt 8 to the sheet P. The belt cleaner 9 removes and collects toner that has not been transferred to the sheet P and remains on the intermediate transfer belt 8. The secondary transfer roller 11 transports the sheet P to the fixing device 17. The fixing device 17 has two rotating bodies (a fixing roller 22 and a pressure roller 21), and applies heat and pressure to the sheet P and the toner image to fix the toner image onto the sheet P. As the fixing roller 22 and the pressure roller 21 rotate, the sheet P is transported to the discharge rollers 20. The discharge rollers 20 discharge the sheet P to the outside of the image forming apparatus 101.

[0021] [Paper feed tray] 4 is a plan view showing the outline of the upper sheet feed cassette 13a and the lower sheet feed cassette 13b. Since the upper sheet feed cassette 13a and the lower sheet feed cassette 13b have the same configuration, the suffixes a and b of the reference numerals are omitted in FIG.

[0022] An arrow h indicates the conveying direction of the sheet P by the sheet feed roller 14. The regulating plates 131 and 132 are members that regulate the position of the sheet P in the width direction. In FIG. 4, the width direction of the sheet P is a direction perpendicular to the conveying direction of the sheet P. In FIG. 4, the long side of the sheet P is parallel to the conveying direction of the sheet P. The short side of the sheet P is perpendicular to the conveying direction of the sheet P. The regulating plate 131 can move in the direction indicated by the arrow i. The regulating plate 132 can move in the direction indicated by the arrow j. The regulating plates 131 and 132 can move in conjunction with each other to center the sheet P with respect to the conveying path 15. The regulating plate 133 can move freely in the direction indicated by the arrow k and regulates the position of the end of the sheet P in the conveying direction of the sheet P. By moving the regulating plates 131, 132, and 133, the upper sheet feed cassette 13a and the lower sheet feed cassette 13b can each accommodate sheets P from A6 size to A4 size. However, all sheets P from A6 size to A4 size are placed vertically as shown in Fig. 4. "Vertical placement" means that the sheet P is arranged so that the long side of the sheet P is parallel to the conveying direction.

[0023] [Server control section] As shown in FIG. 5(A), the server 103 has a control unit 501, an interface unit 502, a communication unit 504, and a storage unit 505. The control unit 501 has a CPU that executes a control program stored in the storage unit 505. The control program may be a diagnostic program 206. As a result, the server 103 may function as a diagnostic device instead of the imaging device 102. However, even when the server 103 functions as a diagnostic device, the sheet image is generated by the imaging device 102. The interface unit 502 includes an input device and a display device. The interface unit 502 may display a diagnosis result created in the imaging device 102 or the server 103. The communication unit 504 is a communication circuit that communicates with the imaging device 102 and the image forming device 101 via a network. The storage unit 505 has a ROM, a RAM, an SSD (solid state drive), and an HDD (hard disk drive).

[0024] [Control unit of image forming device] FIG. 5B shows the control unit 40 of the image forming apparatus 101. The CPU 511 controls each unit of the image forming apparatus 101 by executing a control program stored in the storage unit 515. For example, when the CPU 511 receives a print instruction for a diagnostic image from the imaging apparatus 102, the CPU 511 controls the image forming apparatus 101 to form the diagnostic image on the sheet P. At this time, the CPU 511 controls the power supply circuit 421 to generate a charging bias voltage, a developing bias voltage, and a transfer bias voltage. The CPU 511 also drives the motor 522 to rotate various rotating bodies such as the photoconductor 1. The interface unit 512 includes an input device and a display device. The interface unit 512 may display a diagnosis result created by the imaging apparatus 102 or the server 103. Alternatively, when the CPU 511 functions as a diagnosis apparatus by executing a diagnostic program, the CPU 511 obtains a sheet image from the imaging apparatus 102 via the communication unit 41 and performs image distortion correction and image diagnosis. The storage unit 515 includes a RAM, a ROM, an SSD, and an HDD. The storage unit 515 stores model information 516, which is identification information of the image forming apparatus 101. The CPU 511 may store information indicating the use history of the image forming apparatus 101 (e.g., the cumulative number of images formed) or the replacement time of each component in the storage unit 515 as history data 517. The storage unit 515 stores size information 518 indicating the size input or selected by the user through the interface unit 512, or the size of the sheet P detected by the sheet sensor 23 or the size sensors 523a and 523b. The first size sensor 523 and the second size sensor 523b are optional. The first size sensor 523a detects the size of the sheet P (e.g., the length of the long side and the length of the short side) based on the positions of the regulating plates 131, 132, and 133. The second size sensor 523b may be a line sensor provided on the conveying path 15. The line sensor has a light source (light emitting element) and a plurality of light receiving elements arranged in parallel to the width direction (direction perpendicular to the conveying direction) of the conveying path 15. Light from the light source toward the plurality of light receiving elements is blocked by the sheet P. Therefore, the size sensor 523b can detect the length of the short side of the sheet P from the number of light receiving elements that cannot receive the light among the plurality of light receiving elements.Furthermore, the size sensor 523b can detect the length of the long side of the sheet P from the time during which the sheet P blocks light and the conveying speed of the sheet P (for example, 180 mm / sec).

[0025] [flowchart] Diagnostic equipment processing 6A shows an image diagnosis method executed by a CPU built in the control unit 201 of the imaging device 102 in accordance with a diagnostic program 206. When the control unit 201 is instructed to start the diagnostic program 206 through the interface unit 202, the control unit 201 starts the diagnostic program 206 and executes the following processing.

[0026] In S601, the control unit 201 acquires model information 516 and size information 518 of the image forming apparatus 101. For example, the control unit 201 connects to the image forming apparatus 101 via the communication unit 204 and transmits a request to the image forming apparatus 101. As a result, the control unit 201 receives the model information 516 and size information 518 via the communication unit 204. The model information 516 includes the product number and model name of the image forming apparatus 101. The size information 518 may include the size of the sheets Pa accommodated in the upper paper feed cassette 13a and the size of the sheets Pb accommodated in the lower paper feed cassette 13b.

[0027] In S602, the control unit 201 selects a diagnostic image and a paper feed cassette. For example, the control unit 201 selects diagnostic image data 207 associated with the model information 516 from among a plurality of diagnostic image data 207 stored in the storage unit 205. This association may be held by the case collection 210. The control unit 201 may also select diagnostic image data 207 based on history data 517 acquired from the image forming apparatus 101. For example, the control unit 201 identifies, among the components of the image forming apparatus 101, components that are close to their designed expiration date or that have been used beyond their expiration date, based on the history data 517. Furthermore, the control unit 201 selects diagnostic image data 207 of a diagnostic image that is easy to detect image defects that may occur in the identified components. The control unit 201 selects the upper paper feed cassette 13a or the lower paper feed cassette 13b based on the size information 518. In general, image defects can be detected in a wider range in the width direction of the sheet P for a large-sized sheet P than for a small-sized sheet P. Therefore, the control unit 201 may select the upper sheet feeding cassette 13a based on the size information 518.

[0028] 7A shows an example of a diagnostic image 700 generated based on diagnostic image data 207. Diagnostic image 700 includes a monochromatic pattern 701 and a halftone pattern 702. Monochromatic pattern 701 includes a test image formed with the monochromatic colors of Y, M, C, and K. Halftone pattern 702 includes a gradation image formed by mixing all of Y, M, C, and K.

[0029] In S603, the control unit 201 transmits a print instruction for the diagnostic image 700 to the image forming apparatus 101. The print instruction includes the diagnostic image data 207 on which the diagnostic image 700 is based, and information specifying the paper feed cassette 13.

[0030] In S604, the control unit 201 controls the camera 203 to capture the diagnostic image 700 formed on the sheet P by the image forming apparatus 101, and generate a sheet image. For example, the control unit 201 may display a guidance message on the display device of the interface unit 202 to prompt the user to capture the diagnostic image 700. The user operates the input device of the interface unit 202 according to the guidance, and captures the diagnostic image 700 on the sheet P. As a result, a sheet image 208 is generated and stored in the RAM area of ​​the storage unit 205.

[0031] FIG. 7B shows a sheet image 208a with a drum ghost. The monochromatic pattern 701 is an image pattern that is useful for detecting an image defect called a drum ghost. The drum ghost is an image defect that may occur due to deterioration of the photoconductor 1. As shown in FIG. 7B, the monochromatic pattern 701 formed earlier appears as an afterimage 703. Here, the distance L1 between the monochromatic pattern 701 and the afterimage 703 coincides with the perimeter of the photoconductor 1. The density of the afterimage 703 is different from the density of the regular halftone pattern 702. The control unit 201 can determine the presence or absence of a drum ghost by comparing the image density at a position distanced by the distance L1 from the monochromatic pattern 701 with a reference density (the density of the halftone pattern 702). Such a rule for determining a drum ghost is included in the case study collection 210.

[0032] The halftone pattern 702 is an image pattern for detecting the occurrence of defects mainly caused by the conveyance of the sheet P. A drive gear, a conveyance roller, or the like may deteriorate or break due to wear caused by long-term use. Image defects 704a to 704c occur on the halftone pattern 702 of the sheet image 208b shown in FIG. 7(C). Since the interval L2 between the image defects 704a to 704c corresponds to the circumferential length of the drive gear or the conveyance roller, the control unit 201 can identify that the drive gear or the conveyance roller is defective. Such a determination rule is also included in the case study collection 210.

[0033] 7D shows an image defect 705 (vertical stripes) that can occur when foreign matter accumulates on the transport path 15. In this example, the foreign matter causing the image defect accumulates at a position a distance L3 away from the center of the transport path 15 in the width direction.

[0034] In S605, the control unit 201 corrects the sheet image 208 based on the size information 518. Since the user holds the imaging device 102 in his / her hand to capture the diagnostic image 700 on the sheet P, the sheet P and the diagnostic image 700 shown in the generated sheet image 208 may be rotated or distorted. Therefore, it is necessary to reduce the distortion of the sheet P and the diagnostic image 700 shown in the sheet image 208.

[0035] FIG. 8(A) shows a sheet image 208. A photographing frame 800 is a frame showing the photographing field of view of the camera 203. An image area 801 shows an area in the sheet image 208 in which the sheet P on which the diagnostic image 700 is formed is photographed. In this example, the sheet P is rotated with respect to the photographing frame 800. Furthermore, if the imaging surface (image sensor) of the camera 203 and the sheet P are not parallel, the image of the sheet P will be distorted. Thus, if the position of the image defect is measured in the distorted sheet image 208, the error in the measurement result will be large. Therefore, the control unit 201 corrects the distortion of the sheet image 208.

[0036] First, the control unit 201 measures the lengths of the four sides of the image area 801 in which the sheet P appears in the sheet image 208. The control unit 201 counts the number of pixels corresponding to the four sides of the image area 801 to measure the length U0 of one long side, the length V0 of the other long side, the length W0 of one short side, and the length X0 of the other short side. The control unit 201 may measure the lengths of the four sides using a measurement function installed in the camera 203. As an example, it is assumed that U0=260 mm, V0=320 mm, W0=200 mm, and X0=220 mm.

[0037] FIG. 8(B) shows an image area 802 obtained by correcting the image area 801. The image area 802 is rotated after the dimensions of each side are corrected. The rotation correction may be performed before the dimension correction of each side. As shown in FIG. 8(A), the original image area 801 is tilted at an inclination ε0 with respect to the photographed frame 800. The interior angles α0, β0, γ0, and δ0 of the image area 801 are also not 90 degrees. Therefore, image correction is performed such that the inclination ε0 becomes 0 degrees and the interior angles α0, β0, γ0, and δ0 become α1, β1, γ1, and δ1=90°.

[0038] Furthermore, the control unit 201 recognizes from the size information 518 that the original size of the image area 801 is A4 size. Therefore, the control unit 201 corrects the image area 801, where the long side U0=260 mm and V0=320 mm, to the image area 802, where U1 and V1=297 mm. Furthermore, the control unit 201 corrects the image area 801, where W0=200 mm and V0=220 mm, to the image area 802, where W1 and V1=210 mm. As a result, the sheet image 208 is generated in which the deformation, rotation, etc. of the image have been corrected.

[0039] In S606, the control unit 201 analyzes the sheet image 208 to detect an image defect. For example, the control unit 201 determines whether or not an afterimage 703 occurs at a position that is a distance L1 away from the monochromatic pattern 701. Alternatively, the control unit 201 may detect the afterimage 703, identify the position where the afterimage 703 occurs, and determine whether or not the distance between the monochromatic pattern 701 and the afterimage 703 is the distance L1. Alternatively, the control unit 201 may detect a plurality of image defects 704a to 704c that occur periodically, and measure the interval L2 between the plurality of image defects 704a to 704c. The distance L1 and the interval L2 are values ​​that correlate with the rotation period (perimeter) of the rotating body that causes the image defect, and therefore the rotating body that causes the image defect is identified.

[0040] Incidentally, the distance L1 and the interval L2 may be measured based on the lengths U1 and V1 of the long sides. For example, the control unit 201 may calculate the actual lengths of the distance L1 and the interval L2 by measuring the ratio of the distance L1 and the interval L2 to the length U1 (=V1) and multiplying the ratio by the length U1.

[0041] Similarly, the distance L3 for the vertical streak type image defect 705 shown in Fig. 7(D) is measured based on the lengths W1 and X1 of the short sides. For example, the control unit 201 may measure the ratio of the distance L3 to the length W1 (=X1) and multiply the ratio by the length W1 to calculate the actual length of the distance L3. The control unit 201 knows from the size information 518 that U1, V1 = 297 mm, W1, X1 = 210 mm. Therefore, the control unit 201 can accurately measure L1, L2, and L3.

[0042] In S607, the control unit 201 generates a diagnosis result. The control unit 201 identifies a component part (causing component) constituting the image forming apparatus 101 based on the occurrence position of the image defect. The control unit 201 generates a diagnosis result indicating the mounting position of the causative component in the image forming apparatus 101, the wear state of the causative component, the replacement time of the causative component, the ordering method of the causative component, etc. The diagnosis result may include status information indicating whether each of the multiple components is in a normal state or in a state requiring maintenance. The diagnosis result may include information indicating measures to reduce the image defect (e.g., replacement, repair, cleaning, etc.). Furthermore, if no image defect is detected in S606, the diagnosis result includes information that all components constituting the image forming apparatus 101 are operating normally.

[0043] In S608, the control unit 201 displays the diagnosis result on the display device of the interface unit 202. The control unit 201 may output (transmit) the diagnosis result to the server 103, the image forming apparatus 101, or a personal computer via the communication unit 204, thereby notifying the administrator or maintenance person of the diagnosis result.

[0044] ● Processing of image forming devices 6B shows a method of providing model information 516 and size information 518 executed by CPU 511 of image forming apparatus 101. In S611, CPU 511 receives a request (transmission request) for model information 516 and size information 518 from imaging device 102. In S612, CPU 511 reads out model information 516 and size information 518 from storage unit 515, and transmits model information 516 and size information 518 to imaging device 102 via communication unit 41.

[0045] In S613, the CPU 511 receives a print instruction for the diagnostic image 700 from the imaging device 102 via the communication unit 41. The print instruction includes information specifying the paper feed cassette 13.

[0046] In S614, the CPU 511 forms a diagnostic image 700 on a sheet P in accordance with the print instruction. For example, the CPU 511 drives the paper feed roller 14a to feed a sheet Pa from the upper paper feed cassette 13a specified by the print instruction. Furthermore, the CPU 511 controls the exposure device 7 based on the diagnostic image data 207 received from the imaging device 102. As a result, the diagnostic image 700 is formed on the sheet Pa.

[0047] The storage unit 205 stores a case collection 210 (cause identification information) of an image defect that is expected to occur for each combination of the model information 516 and the diagnostic image. For example, when an afterimage 703 occurs in a combination of the image forming device 101 and the diagnostic image 700, and the distance L1 is equal to the circumference of the photoconductor 1, the case collection 210 indicating that the cause is deterioration of the photoconductor 1 may be stored. In this manner, the case collection 210 may include a combination of the identification information of the image forming device 101 and the identification information of the diagnostic image, characteristic information indicating the characteristics of the image defect, and identification information of the component causing the image defect. The control unit 201 refers to the case collection 210 stored in the storage unit 205, selects the diagnostic image data 207, detects the image defect based on the characteristics of the image defect, and identifies the causative component based on the occurrence position of the image defect. The case collection 210 may include countermeasure information for reducing the image defect. The control unit 201 refers to the case collection 210 to identify a method for reducing the image defect, and includes the method in the diagnosis result 209.

[0048] FIG. 9 is a table for explaining the effect of Example 1. Here, the interval L2 was measured for the horizontal stripe type image defect 704 shown in FIG. 7(C). In Comparative Example 1, the interval L2 is measured based on the long side length U0 in the image area 801 shown in FIG. 8(A) to which the correction process of Example 1 is not applied. In Comparative Example 2, the interval L2 is measured based on the long side length V0 in the image area 801 shown in FIG. 8(A) to which the correction process of Example 1 is not applied. Here, the peripheral length of the photoconductor 1 is assumed to be 75.4 mm. The peripheral length of the pressure roller 21 is assumed to be 72.2 mm. The peripheral length of the fixing roller 22 is assumed to be 78.5 mm.

[0049] According to the first embodiment, the interval L2 is measured as 75.4 mm based on the long side lengths U1 and V1=297 mm based on the size information 518. Therefore, the control unit 201 correctly determines that the component causing the image defect 704 is the photoconductor 1. On the other hand, in the first comparative example, the interval L2 is measured as 72.4 mm based on the length U0 before correction. Therefore, it is erroneously determined that the component causing the defect is the pressure roller 21. In the second comparative example, the interval L2 is measured as 77.4 mm based on the length V0 before correction. Therefore, it is erroneously determined that the component causing the defect is the fixing roller 22. In this way, when diagnosing a plurality of rotating bodies having similar outer diameters, it is important to obtain a reference length.

[0050] In the first embodiment, it is assumed that a plurality of diagnostic images are stored in the storage unit 205 of the imaging device 102, but this is merely an example. The diagnostic image data 207 of the diagnostic image may be stored in the storage unit 505 of the server 103. In this case, the control unit 201 may transmit the model information of the image forming device 101 to the server 103, and the server 103 may read the diagnostic image data 207 corresponding to the model information from the storage unit 505 and transfer it to the imaging device 102. This increases the free space of the storage unit 205. Similarly, the case collection 210 of the image defect may also be stored in the storage unit 505 of the server 103. The control unit 201 of the imaging device 102 transmits the model information and the identification information of the diagnostic image to the server 103, and the control unit 501 of the server 103 transmits the case collection 210 corresponding to these to the imaging device 102. The control unit 201 of the imaging device 102 may measure the characteristic quantities (distance L1, interval L2, etc.) of the image defects using the received case collection 210, and identify the causative component.

[0051] The server 103 may function as a diagnostic device. In this case, the server 103 acquires the size information 518 and the sheet image 208 via the imaging device 102. Thereafter, the control unit 501 executes the same process as the control unit 201 described above to identify the causative part and create a diagnostic result. In this case, the storage unit 505 stores the diagnostic program 206, the diagnostic image data 207, the sheet image 208, and the diagnostic result 209. Note that the control unit 501 of the server 103 may acquire the size information 518 directly from the image forming device 101. This is because the control unit 501 can communicate with the image forming device 101 via the communication unit 504.

[0052] FIG. 7A shows a diagnostic image 700 of one page, but this is only an example. As shown in FIG. 10, a diagnostic image 700 consisting of multiple pages may be used. In this example, the relationship between the circumferential length L4 of the intermediate transfer belt 8 and three sheets Pa1, Pa2, and Pa3 on which the diagnostic image 700 is formed is shown. The first sheet Pa1 has the diagnostic image 700 formed thereon. The second sheet Pa2 has only the halftone pattern 702 formed thereon of the diagnostic image 700. The third sheet Pa3 has only the halftone pattern 702 formed thereon of the diagnostic image 700. The image defects 1000a and 1000b caused by the intermediate transfer belt 8 occur periodically at intervals corresponding to the circumferential length L4. d is the sheet interval between the preceding sheet and the succeeding sheet when passing through the secondary transfer section. The control unit 201 generates sheet images 208 from the three sheets Pa1, Pa2, and Pa3, applies the above-mentioned correction, and measures the interval L4' between the image defects 1000a and 1000b. Since the interval L4' is approximately equal to the circumference L4, the control unit 201 determines that the intermediate transfer belt 8 is the causative part.

[0053] According to the first embodiment, the diagnostic system 100 can diagnose components of the image forming apparatus 101 using the imaging device 102 such as a smartphone. This allows the user to diagnose the image forming apparatus 101 more easily than before. Furthermore, the read result (sheet image 208) of the diagnostic image 700 formed on the sheet P is corrected based on the size information 518 of the sheet P. This improves the measurement accuracy of the feature amount of the image defect, and also improves the accuracy of the diagnostic result.

[0054] <Example 2> In the first embodiment, the size sensor 523a mainly monitors the positions of the regulating plates 131, 132, and 133 provided on the upper sheet feed cassette 13a and the lower sheet feed cassette 13b, respectively, to detect the size of the sheet P. Such a size sensor 523a may erroneously detect the size of the sheet P if the regulating plates 131, 132, and 133 are not positioned correctly.

[0055] Therefore, in the second embodiment, in addition to the size information obtained by the size sensor 523a, the size information of the sheet P is obtained by the sheet sensor 23 provided on the conveying path 15.

[0056] Fig. 11(A) shows an image diagnosis method executed by a CPU built in the control unit 201 of the imaging device 102 in accordance with a diagnostic program 206. In Fig. 11(A), the same or similar steps as those in Fig. 6(A) are given the same reference numerals, and the description thereof is incorporated herein by reference. In the second embodiment, the size information 518 acquired by the size sensor 523a is referred to as first size information. The size information 518 acquired by the sheet sensor 23 is referred to as second size information. In the second embodiment, the first size information is mainly used to select the paper feed cassette 13, and the second size information is used to correct the sheet image.

[0057] When S603 ends, the control unit 201 proceeds to S1101. In S1101, the control unit 201 acquires second size information from the image forming apparatus 101 via the communication unit 204. For example, a request signal for acquiring the second size information may be transmitted. Thereafter, the control unit 201 proceeds to S604, where the control unit 201 generates a sheet image 208. In S1102, the control unit 201 corrects the sheet image 208 based on the second size information. S1102 is similar to S605. While the first size information is used in S605, the second size information is used in S1102. Compared with the first size information, the second size information is more accurate. Therefore, the correction of the sheet image 208 becomes more accurate, the measurement of the feature amount of the image defect becomes more accurate, and the diagnosis result becomes more accurate.

[0058] Fig. 11(B) shows a method for providing model information 516, first size information, and second size information executed by CPU 511 of image forming apparatus 101. In Fig. 11(A), the same reference numerals are given to steps that are the same as or similar to those in Fig. 6(A), and the description thereof is incorporated herein by reference.

[0059] 11(B), a new step S1111 is added between S613 and S614. Furthermore, S1112 is added after S614. Note that S1112 may be added before S614.

[0060] In S1111, the CPU 511 obtains size information 518 (second size information) of the sheet P using the sheet sensor 23. If the sheet sensor 23 is a sensor that detects the presence or absence of the sheet P, the CPU 511 measures the time (passing time T) during which the sheet sensor 23 detects the leading edge to the trailing edge of the sheet P using a timer or counter. The CPU 511 may calculate the length of the long side of the sheet P by multiplying the passing time T by the conveying speed (e.g., 180 mm / s). This calculation may be performed by the control unit 201. In this case, the control unit 201 may specify the conveying speed based on the model information 516, or may be notified of the conveying speed by the CPU 511. In this manner, the CPU 511 obtains the second size information. Thereafter, the CPU 511 executes S614 and proceeds to S1112. Note that, if the second size information indicates only the length of the long side of the sheet P (the length in the conveying direction), the length of the short side of the sheet P (the length in the width direction) may be obtained from the first size information.

[0061] In S1112, the CPU 511 transmits the second size information via the communication unit 41. The second size information is sufficient as long as it is information capable of identifying the size of the sheet P, and may be either (i) the length of the long side of the sheet P, or (ii) the passing time T and the conveying speed.

[0062] In the above description, it is assumed that the sheet sensor 23 can measure the length of the sheet P in the transport direction. However, instead of the sheet sensor 23, a second size sensor 523b provided in the transport path 15 may detect the length of the sheet P in the transport direction and the length of the sheet P in the width direction. The size sensor 523b may be a sensor using a line sensor. In this case, the line sensor extends in a direction perpendicular to the transport direction in the transport path 15. Thereby, the second size information may include both the length of the long side and the length of the short side of the sheet P. In this case, the image correction in S1102 uses the length of the long side and the length of the short side of the sheet P acquired from the second size information. The first size information acquired by the first size sensor 523a provided in the paper feed cassette may not be used for image correction.

[0063] According to the second embodiment, the second size information is used, which is more accurate than the first size information. Therefore, the sheet image 208 is corrected more accurately, the feature amount of the image defect is measured more accurately, and the diagnosis result is also more accurate.

[0064] <Example 3> When the diagnostic image 700 occupies a wide area of ​​the sheet P, a large amount of unfixed toner image is transferred to the sheet P at the secondary transfer section. The unfixed toner image has a lubricating effect between the intermediate transfer belt 8 and the sheet P. As a result, the sheet P may slip, the conveying speed of the sheet P may decrease, and the measurement result of the sheet P by the sheet sensor 23 may become inaccurate. Therefore, in the third embodiment, the sheet P whose size is measured by the sheet sensor 23 or the second size sensor 523b and the sheet P on which the diagnostic image 700 is printed are different sheets P. In particular, less toner is transferred to the sheet P whose size is measured compared to the sheet P on which the diagnostic image 700 is printed. For example, no toner may be transferred to the sheet P whose size is measured.

[0065] FIG. 12(A) shows an image diagnosis method executed by a CPU built in the control unit 201 of the imaging device 102 according to a diagnostic program 206. In FIG. 12(A), the same or similar steps as those in FIG. 6(A) or FIG. 11(A) are given the same reference numerals, and the description thereof is incorporated herein. The user stores a plurality of sheets P in the upper sheet feed cassette 13a in advance. This may be realized by the control unit 201 displaying a message prompting the user to store the sheets P on the interface unit 202. In the third embodiment, steps S1201 and S1202 are inserted between steps S602 and S603. The sheet P on which the measurement image is formed and the sheet P on which the diagnostic image 700 is formed are sheets P of the same brand and from the same production lot. Generally, the sheets P are contained in one package for each predetermined number of sheets (e.g., 1000 sheets). Therefore, the sheet P on which the measurement image is formed and the sheet P on which the diagnostic image 700 is formed may be sheets P contained in the same package and sold. This will result in a very small error between the size of the sheet P on which the measurement image is formed and the size of the sheet P on which the diagnostic image 700 is formed.

[0066] In S1201, the control unit 201 transmits to the image forming apparatus 101 a print instruction for a measurement image suitable for measuring the size of the sheet P. A measurement image is an image that is less likely to cause a decrease in the conveying speed due to an unfixed toner image compared to the diagnostic image 700. For example, a measurement image is a solid white image to which no toner is transferred, or an image to which a small amount of toner is transferred. Note that the paper feed cassette specified by the print instruction for the measurement image is basically the same as the paper feed cassette specified by the print instruction for the diagnostic image 700. This improves the correction accuracy of the sheet image.

[0067] In S1202, the control unit 201 acquires second size information from the image forming apparatus 101 via the communication unit 204. Here, the second size information includes size information acquired based on the sheet P on which the measurement image is formed. The second size information is sufficient as long as it is information capable of identifying the size of the sheet P, and may be either (i) the length of the long side of the sheet P, or (ii) the passing time T and the conveying speed.

[0068] The second size information is then used in S1102 to correct the sheet image 208. As described with reference to FIG. 8(A) and FIG. 8(B), the image area 802 is corrected so that the lengths U1, V1, W1, and X1 of the four sides match the second size information. Meanwhile, as described in the first embodiment, the control unit 201 may provisionally correct the image area 802 so that the lengths U1, V1, W1, and X1 of the four sides match the first size information. Thereafter, the control unit 201 may again correct the image area 802 so that the lengths U1, V1, W1, and X1 of the four sides of the corrected image area 802 match the second size information.

[0069] According to the third embodiment, the second size information is obtained using a sheet P different from the sheet P on which the diagnostic image 700 is formed. In particular, the sheet P on which the measurement image is formed is less susceptible to reduction and variation in the conveying speed compared to the sheet P on which the diagnostic image 700 is formed. Therefore, the length of the sheet P in the conveying direction can be obtained more accurately. As a result, the third embodiment can provide a more accurate diagnosis result compared to the second embodiment.

[0070] <Example 4> 13 shows an example of functions that are realized by CPU 1300 that can be mounted on control unit 201, 501 by executing diagnostic program 206. The functions shown in Fig. 13 may be distributed among control units 201, 501 and control unit 40, or may be integrated into one of control units 201, 501 and control unit 40. However, it is sufficient that camera 203 that takes photographs is located independently of image forming apparatus 101.

[0071] The acquiring unit 1301 acquires size information 518 from the image forming apparatus 101 or the interface unit 202. The acquiring unit 1301 acquires model information 516 of the image forming apparatus 101. The acquiring unit 1301 acquires the sheet image 208 generated by the camera 203. In other words, the acquiring unit 1301 functions as an acquiring unit that acquires the sheet image 208 acquired by imaging the sheet P on which the diagnostic image 700 is formed by the image forming apparatus 101.

[0072] The selection unit 1305 selects the diagnostic image 700 corresponding to the model information 516 by referring to the case collection 210. The selection unit 1305 may also select the diagnostic image 700 corresponding to the model information 516 and the history data 517 by referring to the case collection 210. Furthermore, the selection unit 1305 may select a measurement image before the diagnostic image and pass it to the instruction unit 1306. The instruction unit 1306 selects the paper feed cassette 13a based on the size information 518. For example, the size information 518 may indicate that the paper feed cassette 13a contains A4 size sheets Pa and the paper feed cassette 13b contains B5 size sheets Pb. In this case, the instruction unit 1306 selects the paper feed cassette 13a and reflects it in the print instruction. The instruction unit 1306 transmits a print instruction for the image selected by the selection unit 1305 to the image forming apparatus 101.

[0073] The correction unit 1312 corrects the image area 801 included in the sheet image 208 to the image area 802 based on the size information 518 acquired by the sheet sensor 23 or the size sensor 523. As described above, the correction unit 1312 rotates the image area 801 so that the inclination ε0 of the image area 801 becomes zero. The correction unit 1312 also transforms the image area 801 so that the angles α0, β0, γ0, and δ0 of the four corners of the image area 801 become 90 degrees. Furthermore, the correction unit 1312 changes the lengths U0, V0, W0, and X0 of the four sides so that they each match the size information 518. As a result, the sheet image 208 including the corrected image area 802 is generated.

[0074] The defect detection unit 1313 refers to the case collection 210 and detects image defects (e.g., afterimage 703) from the image area 802. The case collection 210 includes features of the image defects (the size of the afterimage 703 and the density difference from the monochromatic pattern 701). The measurement unit 1314 refers to the case collection 210 and measures the feature quantities (e.g., L1, L2, L3, L4) of the image defects. The cause identification unit 1315 refers to the case collection 210 and identifies the causative part corresponding to the feature quantity acquired by the measurement unit 1314 and the countermeasure method (e.g., replacement, repair, cleaning) corresponding to the causative part, and creates a diagnosis result. The result notification unit 1316 outputs the diagnosis result to the interface units 202, 502, and 512. The interface units 202, 502, and 512 display the diagnosis result.

[0075] <Technical ideas derived from examples> As described above, the diagnostic system 100 has the camera 203, a receiving function for receiving an image from the camera 203, a diagnostic function, and a notification function. Here, the receiving function, the diagnostic function, and the notification function may be implemented in the imaging device 102, or may be implemented in another device. For example, the receiving function, the diagnostic function, and the notification function may be distributed among the image forming device 101, the imaging device 102, and the server 103 (information processing device) including a personal computer. For example, the imaging device 102 may only acquire the sheet image 208, and the remaining functions may be installed in an information processing device such as a personal computer.

[0076] As in the embodiment described above, the imaging device 102 may also function as a diagnostic device, and the diagnostic device may be realized by a single application program. This will improve the convenience for the operator.

[0077] [Point 1, 19-22] The image forming apparatus 101 is an example of an image forming apparatus that forms a diagnostic image 700 on a sheet P. The imaging device 102 and the camera 203 are an example of an imaging device that images the sheet P on which the diagnostic image 700 is formed by the image forming apparatus 101 and outputs a sheet image 208. The control units 201 and 501 and the communication unit 504 may function as a receiving unit that receives a sheet image from the imaging device (camera 203) that outputs the sheet image. The imaging device 102 and the server 103 are an example of a diagnostic device that diagnoses the image forming apparatus 101 based on the sheet image 208. The control unit 201, the interface unit 202, and the communication unit 204 are an example of an acquiring unit that acquires size information 518 indicating the size of the sheet P. The control units 201 and 501 function as a diagnostic unit that executes a diagnosis of components of the image forming apparatus 101 based on the size information 518 and the occurrence position of an image defect in the sheet image 208. The interface units 202, 502 and the communication units 204, 504 function as output units that output the diagnosis results of the diagnosis units. In this way, according to the first to third embodiments, by using the imaging device 102, it becomes possible to diagnose the image forming apparatus 101 more easily than before. Furthermore, since the size information 518 of the sheet P on which the diagnostic image 700 is formed is used for diagnosis, it is expected that the diagnosis results will be more accurate.

[0078] [Point 2] The control unit 201, 501 may resize the image area 801 of the sheet P shown in the sheet image 208 based on the size information 518. Furthermore, the control unit 201, 501 may execute diagnosis of components of the image forming device 101 based on the occurrence position of an image defect in the resized image area 802. Since the imaging device 102 takes a photograph while being held by the user's hand, the image area 801 in the sheet image 208 is likely to be distorted. Therefore, by correcting the image area 801 based on the size information 518, the diagnosis result becomes more accurate.

[0079] [Point 3] The size information 518 may be information including at least one of the length of the long side and the length of the short side of the sheet P. The length of one of the long side and the short side may be estimated from the length of the other side. This is because the lengths of the long side and the short side are known for standard sizes such as A4 and B5.

[0080] [Point 4] The size information 518 may include both the length of the long side and the length of the short side of the sheet P. The control unit 201, 501 may resize the image area 801 of the sheet P shown in the sheet image 208 so that the length of the long side and the length of the short side of the image area 801 of the sheet P are closer to the length of the long side and the short side of the sheet P included in the size information 518. This allows the image area 801 to be corrected more accurately, which will lead to more accurate diagnosis results.

[0081] [Point 5] The server 103 (which may be a personal computer) is an example of an information processing device capable of communicating with the image forming apparatus 101. The control unit 201 may acquire the size information 518 via the information processing device.

[0082] [Point 6] The sheet sensor 23 and the size sensors 523a and 523b are an example of a detection unit that detects the size of the sheet P. The control units 201 and 501 may acquire size information 518 that indicates the size of the sheet P detected by the detection unit.

[0083] [Point 7] The paper feed cassettes 13a and 13b are an example of a storage unit capable of storing a plurality of sheets. The size sensor 523a may be configured to detect the size of the sheet P stored in the storage unit.

[0084] [Points 8 and 9] The transport path 15 is an example of a transport path that transports the sheet P. The sheet sensor 23 and the size sensor 523b may be configured to detect the size of the sheet P in the transport path 15. This will result in more accurate size information 518. The sheet sensor 23 and the size sensor 523b may detect the size of the sheet P based on the passing time T of the sheet P transported on the transport path 15 and the transport speed of the sheet.

[0085] [Point 10] The size sensor 523b may have a plurality of light receiving elements arranged along a direction perpendicular to the conveying direction of the sheet P in the conveying path 15. Furthermore, the size sensor 523b may be configured to detect the size of the sheet P in a direction perpendicular to the conveying direction of the sheet P based on the light receiving results of the plurality of light receiving elements. This makes it possible to obtain not only the length of the sheet P in the conveying direction but also the length in the width direction.

[0086] [Point 11] As described in the third embodiment, the sheet P whose size is detected by the detection means and the sheet P on which the diagnostic image is formed may be separate sheets. This can make the size information of the sheet P more accurate.

[0087] [Point 12] The information processing device (for example, the server 103 and the personal computer) may have a notification means (for example, the interface unit 502) for notifying the diagnosis result. This makes it possible to notify the user of the information processing device of the diagnosis result.

[0088] [Points 13 and 14] The diagnostic result may include information indicating the component (e.g., photoconductor 1) that is presumed to be the cause of the image defect. This will allow the user to easily understand which component requires maintenance. The diagnostic result may include information indicating a countermeasure for reducing the image defect. This will allow the user to easily understand what kind of maintenance is required.

[0089] [Points 15, 16, 21] The diagnostic device (e.g., control unit 201) and the imaging device 102 may be housed in one housing. That is, the imaging device 102 may function as the diagnostic device. The diagnostic device and the imaging device 102 may be implemented in a camera-equipped portable communication device (e.g., a smartphone or a tablet terminal) or a digital camera. Camera-equipped portable communication devices are very widespread. Thus, a user can download the diagnostic program 206 from a server device and install it in the camera-equipped portable communication device. That is, a user can easily introduce the diagnostic device.

[0090] [Point 17] The diagnostic device may be mounted on the image forming apparatus 101. In this case, some of the above-described processes (e.g., S605 to S608) that are described as being executed by the control unit 201 will be executed by the control unit 40. Even in such a case, the imaging device 102 is provided independently of the image forming apparatus 101. That is, the sheet image 208 is still acquired by the imaging device 102. This will enable the diagnostic process to be executed even by an image forming apparatus 101 that does not have an image sensor.

[0091] [Point 18] The diagnostic device may be mounted on a server computer (e.g., server 103) capable of communicating with the imaging device 102. This makes it possible to obtain diagnostic results even when the imaging device 102 has low information processing capabilities or when the free space of the memory unit 205 is low.

[0092] The invention is not limited to the above-described embodiments, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0093] 100: diagnostic system, 101: image forming apparatus, 201: control unit, 202: interface unit, 203: camera, 204: communication unit

Claims

1. an image forming device for forming a diagnostic image on a sheet; a diagnostic image formed by the image forming apparatus; and an imaging apparatus for imaging a sheet discharged from the image forming apparatus and outputting a sheet image, The imaging device includes: An acquisition means for acquiring size information indicating a size of the sheet; a diagnostic unit for diagnosing components of the image forming apparatus based on the size information and the position of the image defect in the sheet image; an output means for outputting a diagnosis result of the diagnosis means; A diagnostic system comprising:

2. The diagnostic system described in claim 1, characterized in that the diagnostic means corrects distortion of the image area of ​​the sheet shown in the sheet image based on the size information, and performs a diagnosis of components of the image forming device based on the occurrence position of the image defect in the corrected image area.

3. The diagnostic system according to claim 1 , wherein the size information includes at least one of a length of a long side and a length of a short side of the sheet.

4. the size information includes both the length of a long side and the length of a short side of the sheet, The diagnostic system described in claim 3, characterized in that the diagnostic means resizes the image area of ​​the sheet so that the lengths of the long sides and short sides of the image area of ​​the sheet shown in the sheet image are closer to the long sides and short sides of the sheet included in the size information.

5. The image forming apparatus further includes an information processing device capable of communicating with the image forming apparatus, 5. The diagnostic system according to claim 1, wherein the acquisition means is configured to acquire the size information via the information processing device.

6. the image forming apparatus has a detection unit for detecting a size of the sheet, 6. The diagnostic system according to claim 1, wherein the acquiring unit is configured to acquire the size information indicating the size of the sheet detected by the detecting unit.

7. The image forming apparatus has a storage unit capable of storing a plurality of sheets, 7. The diagnostic system according to claim 6, wherein the detection means is configured to detect a size of the sheets stored in the storage means.

8. The image forming apparatus further includes a conveying path for conveying a sheet, 7. The diagnostic system according to claim 6, wherein the detection means is configured to detect a size of the sheet in the transport path.

9. 9. The diagnostic system according to claim 8, wherein the detection means is configured to detect the size of the sheet based on a passing time of the sheet transported along the transport path and a transport speed of the sheet.

10. The diagnostic system described in claim 9, characterized in that the detection means has a plurality of light receiving elements arranged along a direction perpendicular to the transport direction of the sheet in the transport path, and is configured to detect the size of the sheet in the direction perpendicular to the transport direction of the sheet based on the light receiving results of the plurality of light receiving elements.

11. 11. The diagnostic system according to claim 8, wherein the sheet whose size is detected by the detection means and the sheet on which the diagnostic image is formed are different sheets.

12. The imaging device further includes an information processing device capable of communicating with the imaging device, 12. The diagnostic system according to claim 1, wherein the information processing device has a notification unit that notifies the user of the diagnostic result.

13. 13. The diagnostic system according to claim 1, wherein the diagnostic result includes information indicating a component part presumed to be the cause of the image defect.

14. 13. The diagnostic system according to claim 1, wherein the diagnostic result includes information indicating a countermeasure for reducing the image defects.

15. An acquisition means for acquiring size information indicating a size of a sheet; a transmission means for transmitting to an image forming apparatus an instruction for causing the image forming apparatus to form a diagnostic image on the sheet; an acquiring means for acquiring a sheet image obtained by imaging the sheet on which the diagnostic image is formed by the image forming device; a diagnostic unit for diagnosing components of the image forming apparatus based on the size information and the position of the image defect in the sheet image; an output means for outputting a diagnosis result of the diagnosis means; A diagnostic device comprising:

16. A program for causing an information processing device to function as the diagnostic device according to claim 15.

17. 17. The program according to claim 16, wherein the information processing device includes a camera-equipped portable communication device or a digital camera.

18. an image forming device for forming a diagnostic image on a sheet; an imaging device for imaging a sheet on which a diagnostic image is formed by the image forming device and outputting a sheet image; a diagnostic device that diagnoses the image forming apparatus based on the sheet image, The diagnostic device comprises: An acquisition means for acquiring size information indicating a size of the sheet; a diagnostic unit for diagnosing components of the image forming apparatus based on the size information and the position of the image defect in the sheet image; an output means for outputting a diagnosis result of the diagnosis means; A diagnostic system comprising:

19. the diagnostic device is mounted on the image forming device, 20. The diagnostic system of claim 18, wherein the imaging device is provided separately from the image forming device.

20. The diagnostic system according to claim 18 , wherein the diagnostic device is mounted on a server computer capable of communicating with the imaging device.

Images