Image forming apparatus and image forming method

Abstract

To provide an image forming device and an image forming method which can improve efficiency in work for a user to eliminate tear of a sheet.SOLUTION: An image forming device 1 comprises: an image forming part that forms an image on a sheet which is conveyed on a conveying passage 150; a scanner 105 that scans a sheet that is conveyed on the conveying passage 150 to obtain an image formed on the sheet; a measuring device 106 that measures a characteristics value of the sheet that is conveyed on the conveying passage 150; a first determining part that determines whether the sheet is torn or not on the basis of the image obtained by the scanner 105; and an instructing part that instructs an output device to output information including the characteristic value measured by the measuring device 106, when the sheet is determined to be torn during execution of a printing job.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an image forming apparatus and an image forming method. [Background technology]

[0002] Japanese Patent Application Laid-Open Publication No. 2020-3514 (Patent Document 1) discloses an image forming device that acquires characteristic values ​​of the paper to be fed using a media sensor, determines based on the acquired values ​​whether the paper to be fed is of the type of paper set in the job, and stops the job if the paper to be fed is not of the type of paper set in the job. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-3514 Summary of the Invention [Problem to be solved by the invention]

[0004] The image forming apparatus described above can prevent paper waste caused by using the wrong type of paper. However, some waste is caused by using the wrong type of paper, while other waste is caused by factors related to the image forming apparatus (for example, some setting value of the image forming apparatus). When waste actually occurs in the image forming apparatus described above, it is difficult for the user to understand the cause, and it takes time to resolve the waste.

[0005] The present disclosure has been made in consideration of the above-described circumstances, and has as its object to provide an image forming apparatus and an image forming method that improve the user's work efficiency in eliminating waste. [Means for solving the problem]

[0006] An image forming apparatus according to one aspect of the present disclosure includes an image forming unit that forms an image on paper transported along a transport path, a scanner that acquires an image of the paper by scanning the paper transported along the transport path, a measurement unit that measures characteristic values ​​of the paper transported along the transport path, a first determination unit that determines whether the paper is worn out based on the image acquired by the scanner, and an instruction unit that instructs an output device to output information including the measurement values ​​measured by the measurement unit when the paper is determined to be worn out during execution of a print job.

[0007] Preferably, the image forming apparatus further includes an estimation unit that, when it is determined that the paper is worn out, estimates a cause of the wear from the measurement value. The information including the measurement value further includes the cause of the wear.

[0008] Preferably, the image forming apparatus further includes a storage device that stores characteristic values ​​of paper by paper type. When the paper is determined to be worn, the estimation unit estimates the cause of the wear by comparing the measurement value with the characteristic value corresponding to the type specified by the print job.

[0009] Preferably, the characteristic values ​​include a value indicating a first characteristic. The estimation unit sets a value indicating the first characteristic among the characteristic values ​​corresponding to the type specified by the print job as a first threshold, and estimates that the cause of the waste is the wrong type of paper when the value indicating the first characteristic among the measured values ​​exceeds the first threshold.

[0010] Preferably, the value indicating the first characteristic includes at least one of smoothness, basis weight, and paper thickness.

[0011] Preferably, the estimation unit estimates that the cause of the waste is an issue related to the image forming apparatus when a value indicating the first characteristic among the measurement values ​​does not exceed a first threshold value.

[0012] Preferably, the characteristic values ​​further include a value indicating a second characteristic different from the first characteristic. The value indicating the second characteristic is moisture content. The image forming unit is a printer equipped with a fixing unit. The measurement unit is provided downstream of the fixing unit on the conveying path. The estimation unit sets a value indicating the second characteristic among the characteristic values ​​corresponding to the type specified by the print job as a second threshold, and if the value indicating the first characteristic among the measured values ​​does not exceed the first threshold and the value indicating the second characteristic among the measured values ​​exceeds the second threshold, estimates that the cause of the waste is the fixing temperature in the fixing unit, among factors related to the image forming device.

[0013] Preferably, the image forming device further includes a paper feed tray including the tray that contained the paper determined to be worn and at least one other tray excluding the tray. The storage device further stores characteristic values ​​of the paper contained in the paper feed tray as setting values ​​for each tray. The image forming device further includes a second determination unit that, when it is estimated that the cause of the wear is the wrong type of paper, determines whether there is at least one other tray containing paper having characteristics corresponding to the type specified by the print job by setting a characteristic value corresponding to the type specified by the print job as a third threshold and comparing a setting value corresponding to at least one other tray with the third threshold. When it is determined that there is at least one other tray containing paper having characteristics corresponding to the type specified by the print job, the information including the measurement value further includes a message prompting the user to feed paper from the other tray.

[0014] Preferably, the image forming apparatus further includes a transmitting unit that transmits a signal to a measuring unit when the paper is determined to be worn out. The measuring unit is provided downstream of the scanner on the conveying path, and measures characteristic values ​​of the conveyed paper in response to receiving the signal.

[0015] Preferably, the conveying path includes a first conveying path leading to a first tray onto which sheets not determined to be worn are discharged, and a second conveying path leading to a second tray onto which sheets determined to be worn are discharged. The measuring unit is provided on the second conveying path and measures characteristic values ​​of the sheet upon detecting the conveyed sheet.

[0016] Preferably, the image forming unit further forms a test image on the same paper as the paper or on another paper different from the paper. The first determination unit further determines whether or not a change in density of the test image has occurred based on an image of the paper on which the test image has been formed, acquired by the scanner. If the paper is not determined to be worn, the instruction unit further instructs the output device to output the measurement value in response to determining that a change in density of the test image has occurred.

[0017] In another aspect of the present disclosure, an image forming method executed by a computer includes forming an image on paper being transported along a transport path, acquiring an image of the paper by scanning the paper being transported along the transport path, acquiring characteristic values ​​of the paper being transported along the transport path as measurement values, determining whether the paper is worn out based on the acquired image, and if the paper is determined to be worn out during execution of a print job, instructing an output device to output information including the acquired measurement values. [Effects of the Invention]

[0018] According to the present disclosure, it is possible to provide an image forming apparatus and an image forming method that improve the efficiency of a user's work to eliminate waste. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a diagram illustrating an overview of an image forming apparatus according to a first embodiment. [Figure 2] 1 is a block diagram showing a main hardware configuration of an image forming apparatus according to a first embodiment. [Figure 3] FIG. 2 illustrates an example of a print job. [Figure 4] FIG. 2 is a block diagram showing an example of a module realized by a processor in the first embodiment. [Figure 5] FIG. 10 is a diagram illustrating an example of a characteristic information table. [Figure 6] FIG. 10 is a diagram illustrating an example of a tray information table. [Figure 7] FIG. 3 is a diagram showing an example of processing executed by the image forming apparatus in the first embodiment. [Figure 8] FIG. 10 is a diagram illustrating an example of a screen displayed on an operation panel. [Figure 9] FIG. 10 is a diagram illustrating an example of a screen displayed on an operation panel. [Figure 10] FIG. 10 is a diagram illustrating an example of a screen displayed on an operation panel. [Figure 11] FIG. 10 is a diagram illustrating an example of a screen displayed on an operation panel. [Figure 12] FIG. 11 is a block diagram showing an example of a module realized by a processor in the second embodiment. [Figure 13] FIG. 10 is a diagram showing an example of processing executed by the image forming apparatus according to the second embodiment. [Figure 14] FIG. 10 is a diagram showing an image forming apparatus according to a third embodiment. [Figure 15] FIG. 11 is a diagram showing an example of processing executed by an image forming apparatus according to the third embodiment. [Figure 16] FIG. 10 is a diagram showing an example of an inspection image. [Figure 17] FIG. 13 is a diagram showing an example of processing executed by an image forming apparatus according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, embodiments according to the present invention will be described with reference to the drawings. In the following description, the same parts and components are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed descriptions thereof will not be repeated. Note that the embodiments and modifications described below may be selectively combined as appropriate.

[0021] In the following description, the term "user" will be used to refer to a person who maintains an image forming apparatus (serviceman) and a person who manages and / or uses an image forming apparatus (operator).

[0022] [Embodiment 1] (1. Overview of Image Forming Device) An overview of the image forming apparatus in the first embodiment will be described with reference to FIG. 1. FIG. 1 is a diagram for explaining the overview of the image forming apparatus in the first embodiment. The image forming apparatus 1 is connected to a terminal device 500 via a network 99. The image forming apparatus 1 receives a print job including manuscript data to be printed from the terminal device 500, and forms an image on paper based on the print job (hereinafter also referred to as "printing"). The terminal device 500 is configured by, for example, a PC (Personal Computer), a smartphone, a tablet, or the like. The network 99 may be, for example, a public network such as the Internet, a public line, or a public wireless LAN (Local Area Network), or may be a private network such as a LAN or a VPN (Virtual Private Network).

[0023] The image forming apparatus 1 includes a transport path 150 along which paper is transported, a paper feed tray T, and a paper discharge tray 140. Paper is sent out one sheet at a time from the paper feed tray T to the transport path 150. The paper feed tray T includes multiple trays (trays T1 to T6 in this example). Each of the multiple trays stores multiple sheets of paper. The number of trays may be two or more. An image is formed on the paper as it is transported along the transport path 150, and the paper with the image formed is discharged to the paper discharge tray 140 as a printed matter. In the following description, the side where the paper feed tray T is located is referred to as the upstream side of the transport path 150, and the side where the paper discharge tray 140 is located is referred to as the downstream side of the transport path 150.

[0024] The image forming apparatus 1 further includes a printer 104 , a scanner 105 , a measuring device 106 , an operation panel 107 , and a control device 100 .

[0025] The printer 104 is an example of an "image forming unit." The printer 104 forms an image on paper transported along the transport path 150. The printer 104 includes four photoconductors 104A corresponding to cyan, magenta, yellow, and black. A charger, an exposure unit, a developer, and other components are arranged around each of the four photoconductors 104A, forming an image of the corresponding color on each of the four photoconductors 104A. The printer 104 also includes an intermediate transfer belt 104B, a secondary transfer unit 104C, and a fixing unit 104D. The images formed on each of the four photoconductors 104A are transferred to the intermediate transfer belt 104B. The secondary transfer unit 104C transfers the image on the intermediate transfer belt 104B to paper transported along the transport path 150. The fixing unit 104D is disposed downstream of the secondary transfer unit 104C on the conveying path 150, and applies heat and pressure to the paper on which the image has been formed, thereby fixing the image to the paper.

[0026] Scanner 105 is provided downstream of printer 104. Scanner 105 acquires an image of a sheet of paper on which an image is formed, by scanning the sheet of paper being transported along transport path 150. As an example, scanner 105 includes image sensor 105A and image sensor 105B. Image sensor 105A and image sensor 105B are, for example, a complementary metal oxide semiconductor (CMOS) sensor or a charge coupled device (CCD) sensor. Image sensor 105A acquires an image of a first side of the sheet of paper (e.g., the front side) by scanning the first side, and outputs the acquired image to control device 100. Image sensor 105B acquires an image of a second side of the sheet of paper (e.g., the back side) by scanning the second side, and outputs the acquired image to control device 100.

[0027] The measuring device 106 is an example of a "measuring unit." The measuring device 106 measures the characteristic values ​​of the paper being transported along the transport path 150 and outputs the measured characteristic values ​​to the control device 100 as measurement values. As an example, the measuring device 106 is an optical sensor that has an irradiation unit that irradiates light onto the paper and a light receiving unit that receives light reflected by the paper. The sensor detects the characteristic values ​​of the paper from the transmittance, reflectance, etc. when light is irradiated onto the paper.

[0028] The characteristic values ​​include a value indicating a first characteristic and a value indicating a second characteristic. The first characteristic is the smoothness of the surface of the paper, the weight of the paper, or the thickness of the paper. The value indicating the first characteristic is a value indicating the smoothness of the surface of the paper, or a value indicating the weight or thickness of the paper, such as smoothness, basis weight, or paper thickness. The second characteristic is a characteristic different from the first characteristic, and is the amount of moisture contained in the paper. The value indicating the second characteristic is a value indicating the amount of moisture contained in the paper, such as moisture content. In this embodiment, the measuring device 106 measures smoothness, basis weight, and paper thickness as values ​​indicating the first characteristic, and moisture content as a value indicating the second characteristic.

[0029] 1, the measuring device 106 is provided downstream of the fixing unit 104D and upstream of the scanner 105 on the conveying path 150, but the location of the measuring device 106 is not limited to this. As another example, the measuring device 106 may be provided downstream of the scanner 105 (for example, at position P1 in the figure). Furthermore, the location at which the measuring device 106 is provided is not limited to one. As an example, one measuring device 106 may be provided near the paper feed tray T (for example, at position P2 in the figure) and one downstream of the fixing unit 104D. In this case, the measuring device 106 provided near the paper feed tray T measures a value indicating the first characteristic, and the measuring device 106 provided downstream of the fixing unit 104D measures a value indicating the second characteristic.

[0030] Operation panel 107 is an example of an "output device." Operation panel 107 is composed of a display and a touch panel. The display and the touch panel are placed on top of each other, and operation panel 107 accepts operations for image forming apparatus 1 by touch operation. Furthermore, operation panel 107 may include hard buttons for accepting operations for image forming apparatus 1. Furthermore, operation panel 107 not only accepts setting operations but also provides various information to the user.

[0031] The control device 100 determines whether the paper is worn out based on the image acquired by the scanner 105. If the control device 100 determines that the paper is worn out during the execution of a print job, it causes the operation panel 107 to display information including the measurement values ​​measured by the measuring device 106. This information may further include characteristic values ​​of the paper corresponding to the type specified by the print job and the cause of the wear. In addition, this information may further include a method for the user to deal with the problem.

[0032] An engineer can infer the cause of the wear from the measurement values. Furthermore, an experienced operator can infer the cause of the wear from the measurement values ​​and the characteristic values ​​of the paper corresponding to the type specified by the print job. Furthermore, even an inexperienced operator can grasp the cause of the wear if the cause is displayed on the operation panel 107. If the cause of the wear is known, the user can more easily guess how to resolve the wear. This improves the efficiency of the user's work to resolve the wear.

[0033] Furthermore, when the measures that the user should take to eliminate the waste are displayed on the operation panel 107, the measures that the user should take become clear. Therefore, the efficiency of the user's work to eliminate the waste is improved.

[0034] (2. Hardware Configuration) The hardware configuration of image forming apparatus 1 will be described with reference to Fig. 2. Fig. 2 is a block diagram showing the main hardware configuration of the image forming apparatus in embodiment 1. In addition to the above-mentioned printer 104, scanner 105, measuring device 106, operation panel 107, and control device 100, image forming apparatus 1 further includes a conveying unit 103, a communication interface 108, a memory card interface 109, and a storage device 120. These components are connected to each other via an internal bus 119 so that they can communicate with each other.

[0035] The control device 100 includes a processor 101 and a main memory 102. The processor 101 is configured, for example, by at least one integrated circuit. The integrated circuit is configured, for example, by at least one central processing unit (CPU), at least one application specific integrated circuit (ASIC), at least one field programmable gate array (FPGA), or a combination thereof.

[0036] The processor 101 realizes various processes according to this embodiment by loading the program 121 stored in the storage device 120 into the main memory 102 and executing it. The main memory 102 is configured from a volatile memory, and functions as a work memory required for the processor 101 to execute the program.

[0037] The transport unit 103 includes a transport roller and a drive motor for driving the transport roller. The transport roller rotates while holding the paper, thereby transporting the paper.

[0038] The communication interface 108 exchanges data and signals with an external device. The external device is, for example, the terminal device 500 shown in Fig. 1. As an example, the image forming apparatus 1 receives a print job including document data to be printed from the terminal device 500 via the communication interface 108.

[0039] The memory card interface 109 mediates data transmission between the processor 101 and the memory card 109A. The memory card 109A may be a general-purpose semiconductor storage device such as a Secure Digital (SD), a magnetic recording medium such as a flexible disk, or an optical recording medium such as a compact disk read-only memory (CD-ROM).

[0040] Storage device 120 is, for example, a hard disk. As an example, storage device 120 stores a program 121 for implementing various processes according to the present embodiment, and a print job 122.

[0041] The program 121 is provided by being stored in a storage medium such as the memory card 109A. The program 121 is read from the memory card 109A by the memory card interface 109 and installed in the image forming apparatus 1.

[0042] Program 121 may be provided not as a standalone program but as part of an arbitrary program. In this case, the program 121 cooperates with the arbitrary program to realize the processing according to the present embodiment. Even if the program does not include some of the modules, it does not deviate from the spirit of image forming apparatus 1 according to the present embodiment. In addition, some or all of the functions provided by program 121 may be realized by dedicated hardware.

[0043] Furthermore, instead of installing program 121 stored in memory card 109A in image forming apparatus 1, a program downloaded from a distribution server or the like via communication interface 108 may be installed in image forming apparatus 1.

[0044] The print job 122 includes job information and page information in addition to the document data to be printed. The print job will now be described with reference to Fig. 3. Fig. 3 is a diagram showing an example of a print job.

[0045] The print job 122 includes job information and page information. The job information includes a job number, a name that identifies the manuscript data, and the total number of pages of the manuscript data. The page information includes, for each page, the paper size, a number (profile number) that identifies the type of paper, and information (tray number) that indicates which paper feed tray the paper should be fed from. In this way, the type of paper on which an image is to be formed and which paper feed tray the paper should be fed from are specified by the print job in the image forming apparatus 1 (see FIG. 1).

[0046] 2 again, the storage device 120 further stores a correct image 123, a characteristic information table 124, and a tray information table 125. These will be described later.

[0047] (3. Image forming device module) The modules realized by the processor 101 in the first embodiment will be described with reference to Fig. 4. Fig. 4 is a block diagram showing an example of the modules realized by the processor in the first embodiment. In the first embodiment, the processor 101 executes the program 121 to realize a first determination unit 131, an estimation unit 132, a second determination unit 133, and an instruction unit 134.

[0048] The first determination unit 131 determines whether or not the paper is worn out based on the image of the paper acquired by the scanner 105. In detail, the first determination unit 131 determines whether or not the paper is worn out by comparing the image of the paper acquired by the scanner 105 with the correct image 123 stored in the storage device 120.

[0049] The correct image 123 is a correct example of an image formed by the printer 104 (see FIG. 2), and is stored in the storage device 120 based on an input operation by the user. As an example, the correct image 123 is an image obtained by scanning a test print proof. As another example, the correct image 123 may be an image obtained by color-converting a raster image converted from manuscript data (vector image) included in the print job 122 to RGB.

[0050] The first judgment unit 131 compares the image of the paper acquired by the scanner 105 with the correct image 123, and judges whether the paper is worn out by comparing the density, color, position, etc. of the pattern in the image of the paper acquired by the scanner 105 with those in the correct image 123.

[0051] When the first determination unit 131 determines that the paper is worn out, the estimation unit 132 estimates the cause of the wear from the measurement value measured by the measuring device 106. As an example, the estimation unit 132 refers to the characteristic information table 124 and estimates the cause of the wear by comparing the measurement value measured by the measuring device 106 with the characteristic value corresponding to the type specified by the print job.

[0052] The characteristics information table 124 will now be described with reference to Fig. 5. Fig. 5 is a diagram showing an example of the characteristics information table. The characteristics information table 124 is a table that associates paper types with numbers (profile No.) that can identify the types, and paper characteristic values ​​corresponding to the types. The types of characteristic values ​​associated with the characteristics information table 124 match the types of characteristic values ​​measured by the measuring device 106, and in this embodiment, these are smoothness, basis weight, paper thickness, and moisture content.

[0053] 4, when the first determination unit 131 determines that the paper is worn, the estimation unit 132 first refers to the print job 122 and identifies the type of paper specified by the print job 122. Next, the estimation unit 132 extracts characteristic values ​​corresponding to the identified type of paper from the characteristic information table 124. As an example, when the print job 122 is the print job shown in FIG. 3, since "2" is specified as the profile number, the estimation unit 132 extracts the smoothness (AAA_2 to AAZ_2), basis weight (BBB_2 to BBZ_2), paper thickness (CCC_2 to CCZ_2), and moisture content (DDD_2 to DDZ_2) that are associated with the profile number "2" in the characteristic information table 124 shown in FIG. 5.

[0054] Next, the estimation unit 132 sets a value indicating a first characteristic among the extracted characteristic values ​​as a first threshold, and compares values ​​indicating the first characteristic among the measurement values ​​measured by the measuring device 106 with the first threshold for each type of characteristic value. Furthermore, the estimation unit 132 sets a value indicating a second characteristic among the extracted characteristic values ​​as a second threshold, and compares values ​​indicating the second characteristic among the measurement values ​​measured by the measuring device 106 with the second threshold.

[0055] The estimation unit 132 estimates that the cause of the wear is the wrong type of paper when any of the measurement values ​​(smoothness, basis weight, and paper thickness) indicating the first characteristic measured by the measuring device 106 exceeds a first threshold. In detail, the estimation unit 132 estimates that the cause of the wear is the wrong type of paper when the measurement value of at least one of the smoothness, basis weight, and paper thickness exceeds the first threshold.

[0056] On the other hand, if none of the measurement values ​​(smoothness, basis weight, and paper thickness) indicating the first characteristic measured by the measuring device 106 exceed the first threshold, the estimation unit 132 estimates that the cause of the wear is a factor related to the image forming device 1. In detail, if none of the measurement values ​​for smoothness, basis weight, and paper thickness exceed the first threshold, the estimation unit 132 estimates that the cause of the wear is a factor related to the image forming device 1.

[0057] Furthermore, if none of the measurement values ​​(smoothness, basis weight, and paper thickness) indicating the first characteristic measured by the measuring device 106 exceeds the first threshold value, and the value (moisture content) indicating the second characteristic among the measurement values ​​exceeds the second threshold value, the estimation unit 132 estimates that the cause of the wear is the fixing temperature among factors related to the image forming device 1.

[0058] When it is estimated that the cause of the wear is the wrong type of paper, second determination unit 133 determines whether or not there is a tray (hereinafter also referred to as an "alternative tray") that contains paper having characteristics corresponding to the type specified by print job 122, among at least one other tray other than the tray that contains the paper determined to be worn. Second determination unit 133 determines whether or not there is an alternative tray, based on the characteristic values ​​contained in characteristic information table 124 and the setting values ​​contained in tray information table 125.

[0059] Here, the tray information table 125 will be described with reference to Fig. 6. Fig. 6 is a diagram showing an example of the tray information table. The tray information table 125 is a table that associates information about each tray included in the paper feed tray T (see Fig. 1). The user inputs information about each tray from the operation panel 107. As an example, the tray information table 125 associates a number (tray No.) that can identify the tray with the type of paper stored in the tray, the size of the paper, and characteristic values ​​(setting values) of the paper.

[0060] 4 again, when it is estimated that the cause of the wear is the wrong type of paper, second determination unit 133 first refers to tray information table 125 and extracts, for each tray, a setting value corresponding to at least one tray other than the tray specified by print job 122 among paper feed trays T (see FIG. 1). The tray specified by print job 122 is the tray that contained the paper determined to be worn.

[0061] Next, second determination unit 133 refers to print job 122 and identifies the specified paper type. Next, second determination unit 133 extracts characteristic values ​​corresponding to the identified paper type from characteristic information table 124. Next, second determination unit 133 sets the characteristic values ​​extracted from characteristic information table 124 as third threshold values, and compares the setting values ​​extracted from tray information table 125 with the third threshold values ​​for each type of characteristic value.

[0062] If there is a tray to which a setting value that does not exceed the third threshold is associated for all of the compared types, the second determination unit 133 determines that there is an alternative tray and identifies the tray as the alternative tray.

[0063] When the first determination unit 131 determines that the paper is worn out during execution of the print job 122, the instruction unit 134 instructs the operation panel 107 to display information including the measurement values ​​measured by the measuring device 106. The information including the measurement values ​​may include characteristic values ​​of the paper corresponding to the type specified by the print job, the cause of the wear estimated by the estimation unit 132, and a message urging the user to feed paper from an alternative tray identified by the second determination unit 133.

[0064] In addition to or instead of instructing operation panel 107 to display information including the measurement values, instruction unit 134 may instruct terminal device 500 (see FIG. 1) to display the information. Furthermore, if image forming apparatus 1 is equipped with a speaker, in addition to or instead of instructing operation panel 107 to display information including the measurement values, instruction unit 134 may instruct the speaker to output the information. This eliminates the need for the user to be constantly present in front of image forming apparatus 1, thereby improving user convenience.

[0065] (4. Processing Executed by the Image Forming Device) The processing executed by the image forming apparatus 1 will be described with reference to FIG. 7. FIG. 7 is a diagram showing an example of processing executed by the image forming apparatus in the first embodiment. The processing shown in FIG. 7 is an example of processing when a print job including document data consisting of N pages (N is an integer equal to or greater than 1) is executed. Furthermore, it is assumed that the measuring device 106 is provided downstream of the fixing unit 104D and upstream of the scanner 105 on the conveying path 150 (see FIG. 1). The processing shown in FIG. 7 is realized by the processor 101 shown in FIG. 4 executing the program 121 (see FIG. 4).

[0066] In step S1, the processor 101 sets a variable n (n is an integer equal to or greater than 1) to 1.

[0067] In step S2, processor 101 controls conveyance unit 103 (see FIG. 2) to send one sheet of paper from paper feed tray T (see FIG. 1) specified by the print job to conveyance path 150 (see FIG. 1).

[0068] In step S3, the processor 101 controls the printer 104 (see FIG. 2) to form an image of the nth page of the manuscript data on a sheet of paper.

[0069] In step S4, the processor 101 receives the characteristic values ​​(smoothness, basis weight, paper thickness, and moisture content) of the paper measured by the measuring device 106 (see FIG. 2) as measurement values ​​from the measuring device 106.

[0070] In step S5, the processor 101 receives from the scanner 105 an image of the paper sheet captured by the scanner 105 (see FIG. 2).

[0071] In step S6, processor 101 determines whether the paper is worn out by comparing the image of the paper received in step S5 with correct image 123 (see FIG. 4). If it is determined that the paper is worn out (YES in step S6), processor 101 proceeds to step S7. On the other hand, if it is determined that the paper is not worn out (NO in step S6), processor 101 proceeds to step S14.

[0072] In step S7, processor 101 determines whether at least one of the smoothness, basis weight, and paper thickness received in step S4 exceeds a threshold value. The threshold value is the smoothness, basis weight, and paper thickness of the paper corresponding to the type specified by the print job, and is associated with characteristic information table 124 (see FIG. 4).

[0073] If it is determined in step S4 that at least one of the smoothness, basis weight, and paper thickness received exceeds the threshold (YES in step S7), processor 101 proceeds to step S8. On the other hand, if it is determined that none of the smoothness, basis weight, and paper thickness received in step S4 exceeds the threshold (NO in step S7), processor 101 proceeds to step S11.

[0074] In step S8, processor 101 determines whether or not an alternative paper feed tray is available. If it is determined that an alternative paper feed tray is available (YES in step S8), processor 101 proceeds to step S9. On the other hand, if it is determined that an alternative paper feed tray is not available (NO in step S8), processor 101 proceeds to step S10.

[0075] In step S9, processor 101 instructs operation panel 107 (see FIG. 4) to display the measurement value received in step S4, the cause of the waste, and a solution (feeding paper from an alternative paper feed tray).

[0076] Here, screen D1 displayed on operation panel 107 by the processing of step S9 will be described with reference to Fig. 8. Fig. 8 is a diagram showing an example of a screen displayed on the operation panel. Screen D1 is an example of a screen displayed on operation panel 107 by the processing of step S9.

[0077] Screen D1 includes an image 81 showing the measurement values ​​measured by measuring device 106 (see FIG. 2), an image 82 showing the cause of the wear, and an image 83 showing a solution. Screen D1 also includes an image 84 showing the characteristic values ​​of the paper corresponding to the type specified by the print job. The characteristic values ​​of the paper corresponding to the type specified by the print job in image 84 are values ​​associated with characteristic information table 124 (see FIG. 4). Display of images 81 to 84 on operation panel 107 is instructed by instruction unit 134 (see FIG. 4).

[0078] Screen D1 also includes icons 85 corresponding to each tray of paper feed trays T (see FIG. 1), and icons 86 for accepting user operations to change settings. Display of icons 85 and 86 on operation panel 107 is instructed by instruction unit 134. Icons 85 and 86 are icons for accepting a change of paper feed tray to be used. As an example, when the user selects icon 85 corresponding to "Tray 2" and presses icon 86, the paper feed tray to be used is changed from the tray specified in the print job to Tray 2.

[0079] It is sufficient that the screen D1 includes at least the image 81.

[0080] Referring again to FIG. 7, in step S10, processor 101 instructs operation panel 107 to display the measurement value received in step S4, the cause of the waste, and a solution (check the type of paper in the paper feed tray).

[0081] Here, screen D2 displayed on operation panel 107 by the processing of step S10 will be described with reference to Fig. 9. Fig. 9 is a diagram showing an example of a screen displayed on the operation panel. Screen D2 is an example of a screen displayed on operation panel 107 by the processing of step S10.

[0082] Screen D2 includes an image 81 showing the measurement values ​​measured by measuring device 106 (see FIG. 2), an image 82 showing the cause of the wear, and an image 83 showing a method of dealing with the wear. Screen D2 also includes an image 84 showing the characteristic values ​​of the paper corresponding to the type specified by the print job. The characteristic values ​​of the paper corresponding to the type specified by the print job in image 84 are values ​​associated with characteristic information table 124 (see FIG. 4). An instruction unit 134 (see FIG. 4) is used to instruct display of images 81 to 84 on operation panel 107. It is sufficient that screen D2 includes at least image 81.

[0083] 7, in step S11, processor 101 determines whether the moisture content received in step S4 exceeds a threshold value. The threshold value is the moisture content of the paper corresponding to the type specified by the print job, and is associated with characteristic information table 124 (see FIG. 4).

[0084] If it is determined in step S4 that the moisture content received exceeds the threshold value (YES in step S11), the processor 101 proceeds to step S12. On the other hand, if it is determined in step S4 that the moisture content received does not exceed the threshold value (NO in step S11), the processor 101 proceeds to step S13.

[0085] In step S12, the processor 101 instructs the operation panel 107 to display the measurement value received in step S4, the cause of the waste, and the solution (adjustment of the fixing temperature).

[0086] Here, screen D3 displayed on operation panel 107 by the processing of step S12 will be described with reference to Fig. 10. Fig. 10 is a diagram showing an example of a screen displayed on the operation panel. Screen D3 is an example of a screen displayed on operation panel 107 by the processing of step S12.

[0087] Screen D3 includes an image 81 showing the measurement values ​​measured by measuring device 106 (see FIG. 2), an image 82 showing the cause of the wear, and an image 83 showing a method of dealing with the wear. Screen D3 also includes an image 84 showing the characteristic values ​​of the paper corresponding to the type specified by the print job. The characteristic values ​​of the paper corresponding to the type specified by the print job in image 84 are values ​​associated with characteristic information table 124 (see FIG. 4). An instruction unit 134 (see FIG. 4) is used to instruct display of images 81 to 84 on operation panel 107. It is sufficient that screen D3 includes at least image 81.

[0088] Referring again to FIG. 7, in step S13, processor 101 instructs operation panel 107 to display the measurement value received in step S4, the cause of the waste, and a solution (adjustment of items related to the image forming apparatus other than the fixing temperature).

[0089] Here, screen D4 displayed on operation panel 107 by the processing of step S13 will be described with reference to Fig. 11. Fig. 11 is a diagram showing an example of a screen displayed on the operation panel. Screen D4 is an example of a screen displayed on operation panel 107 by the processing of step S13.

[0090] Screen D4 includes image 81 showing the measurement values ​​measured by measuring device 106 (see FIG. 2), image 82 showing the cause of the wear, and image 83 showing a solution. Image 83 may include a message prompting adjustment of a setting value of the image forming apparatus other than the fixing temperature, for example, a setting value related to the paper conveyance speed or the paper feed timing. Screen D4 also includes image 84 showing characteristic values ​​of paper corresponding to the type specified by the print job. The characteristic values ​​of paper corresponding to the type specified by the print job in image 84 are values ​​associated with characteristic information table 124 (see FIG. 4). Display of images 81 to 84 on operation panel 107 is instructed by instruction unit 134 (see FIG. 4). It is sufficient that screen D4 includes at least image 81.

[0091] 7, in step S14, processor 101 determines whether variable n is greater than or equal to N. If it is determined that variable n is greater than or equal to N (YES in step S14), processor 101 ends the series of processes shown in Fig. 7. On the other hand, if it is determined that variable n is less than N (NO in step S14), processor 101 proceeds to step S15.

[0092] In step S15, the processor 101 increments the variable n by 1, and proceeds to step S2.

[0093] Thus, according to the first embodiment, when a sheet is determined to be worn out during execution of a print job, information including the characteristic values ​​(measured values) of the sheet measured by the measuring device 106 is output to an output device such as the operation panel 107. An engineer can infer the cause of the wear from the measured values. If the cause of the wear is known, the user can more easily guess at how to resolve the wear. This improves the efficiency of the user's work to resolve the wear.

[0094] Furthermore, according to the first embodiment, when paper is determined to be worn out during the execution of a print job, the measurement values ​​as well as the paper characteristic values ​​corresponding to the type specified by the print job are output to the output device. A skilled operator can infer the cause of the wear from the measurement values ​​and the paper characteristic values ​​corresponding to the type specified by the print job. If the cause of the wear is known, the user can more easily determine how to resolve the wear. This improves the efficiency of the user's work to resolve the wear.

[0095] Furthermore, according to the first embodiment, when paper is determined to be worn out during the execution of a print job, the cause of the wear is output to the output device in addition to the measurement value. This allows even an inexperienced operator to understand the cause of the wear, improving the efficiency of the user's work to resolve the wear.

[0096] Furthermore, according to the first embodiment, when paper is determined to be worn out during the execution of a print job, the output device outputs the measurement value as well as the measures the user should take to resolve the wear. This clarifies the measures the user should take, improving the efficiency of the user's work to resolve the wear.

[0097] Note that the image forming apparatus 1 may be a color printing machine or a monochrome printing machine. Furthermore, in the above description, the measuring device 106 measures smoothness, basis weight, and paper thickness as values ​​indicating the first characteristic, and measures moisture content as a value indicating the second characteristic. However, the types of characteristic values ​​measured by the measuring device 106 are not limited to this. The measuring device 106 may measure at least one of smoothness, basis weight, and paper thickness as a value indicating the first characteristic. Furthermore, the measuring device 106 may measure ream weight instead of paper thickness as a value indicating the first characteristic. Furthermore, the measuring device 106 may measure resistance instead of moisture content as a value indicating the second characteristic.

[0098] Furthermore, measuring device 106 may measure only the value indicating the first characteristic, and not the value indicating the second characteristic. In that case, in response to determining that none of the smoothness, basis weight, and paper thickness received in step S4 exceed the threshold value (NO in step S7), processor 101 instructs operation panel 107 to display the measurement values ​​received in step S4, the cause of the waste (items related to the image forming apparatus), and how to deal with it (adjustments related to the image forming apparatus), and proceeds to step S14.

[0099] Also, in the example shown in FIG. 7, processor 101 executes the processing of step S11 when it is determined that none of the smoothness, basis weight, and paper thickness received in step S4 exceed the threshold value (NO in step S7), but it may also execute both the processing of step S7 and the processing of step S11 when it is determined that the paper is worn (YES in step S6).

[0100] Furthermore, image forming apparatus 1 may not include estimation unit 132 or second determination unit 133. If image forming apparatus 1 does not include estimation unit 132 or second determination unit 133, in response to the determination that the paper is worn (YES in step S6), processor 101 instructs operation panel 107 to display the measurement values ​​received in step S4, and proceeds to step S14. In this case, processor 101 may instruct operation panel 107 to display the characteristic values ​​of the paper corresponding to the type specified by the print job, in addition to displaying the measurement values ​​received in step S4, and then proceeds to step S14. The characteristic values ​​of the paper corresponding to the type specified by the print job are values ​​associated with characteristic information table 124.

[0101] Also, if the image forming device 1 does not have the second judgment unit 133, the processor 101 proceeds to step S10 in response to determining that at least one of the smoothness, basis weight, and paper thickness received in step S4 exceeds the threshold value (YES in step S7).

[0102] [Embodiment 2] The image forming apparatus in the second embodiment also has a configuration similar to that of the image forming apparatus 1 in the first embodiment. In the second embodiment, the measuring device 106 is provided downstream of the scanner 105 on the conveying path 150 (for example, at position P1 in FIG. 1), and the characteristic values ​​of the paper are measured by the measuring device 106 only when the paper is determined to be worn.

[0103] Modules realized by processor 101 in embodiment 2 will be described with reference to Fig. 12. Fig. 12 is a block diagram showing an example of modules realized by the processor in embodiment 2. In embodiment 2, processor 101 executes program 121 to realize transmission unit 135 in addition to first determination unit 131, estimation unit 132, second determination unit 133, and instruction unit 134 described above.

[0104] When the first determination unit 131 determines that the paper is worn out, the transmitting unit 135 transmits a signal to the measuring device 106. As an example, the transmitting unit 135 cooperates with a signal generating circuit (not shown) to transmit a signal to the measuring device 106. In response to receiving the signal, the measuring device 106 measures the characteristic values ​​of the transported paper.

[0105] The processing executed by the image forming apparatus in the second embodiment will be described with reference to Fig. 13. Fig. 13 is a diagram showing an example of processing executed by the image forming apparatus in the second embodiment. The processing shown in Fig. 13 is an example of processing when a print job including manuscript data consisting of N pages (N is an integer equal to or greater than 1) is executed. The processing shown in Fig. 13 is realized by processor 101 shown in Fig. 12 executing program 121 (see Fig. 12).

[0106] The process shown in Fig. 13 is similar to the process shown in Fig. 7 except that the process of step S6A is added and that the process of receiving measurement values ​​(the process of step S4) is executed after step S6A. Of the processes shown in Fig. 13, the same processes as those shown in Fig. 7 are assigned the same step numbers and will not be described repeatedly.

[0107] First, processor 101 executes steps S1 to S3. Next, processor 101 executes step S5. Next, processor 101 executes step S6. If it is determined that the paper is worn out (YES in step S6), processor 101 proceeds to step S6A. On the other hand, if it is determined that the paper is not worn out (NO in step S6), processor 101 proceeds to step S14.

[0108] In step S6A, the processor 101 transmits a signal to the measuring device 106. After step S6A, the processor 101 proceeds to step S4.

[0109] Next, processor 101 executes step S4, and then proceeds to step S7. Note that the processing from step S7 onwards is as described with reference to FIG.

[0110] Thus, according to the second embodiment, when a paper sheet is determined to be worn out during execution of a print job, information including the characteristic values ​​(measurement values) of the paper sheet measured by the measuring device 106 is output to an output device such as the operation panel 107. This improves the efficiency of the user's work to eliminate the wear.

[0111] Furthermore, according to the second embodiment, the characteristic values ​​of the paper are measured only when the paper is determined to be worn. Although it takes a certain amount of time for the measurement by the measuring device 106, according to the second embodiment, the measurement is performed only when the paper is determined to be worn, so that it is possible to prevent a decrease in the productivity of the image forming apparatus.

[0112] [Embodiment 3] In the third embodiment, the measuring device is provided on a transport path leading to a tray onto which paper determined to be worn is discharged, and measures the characteristic values ​​of the paper upon detecting the paper being transported.

[0113] FIG. 14 is a diagram showing an image forming apparatus according to the third embodiment. Image forming apparatus 1A differs from image forming apparatus 1 (see FIG. 1) in the following three points. The first difference is that image forming apparatus 1A is provided with two types of paper output trays. Image forming apparatus 1A is provided with paper output tray 141 and paper output tray 142. Paper output tray 141 is a tray to which paper that has not been determined to be worn is output, and is an example of a "first tray." Paper output tray 142 is a tray to which paper that has been determined to be worn is output, and is an example of a "second tray."

[0114] The second point is that the paper transport path 150 includes a first transport path 151 that leads to the paper discharge tray 141, and a second transport path 152 that leads to the paper discharge tray 142. The transport unit 103 (see FIG. 2) further includes a switch mechanism 153 for branching the transport path 150 into the first transport path 151 and the second transport path 152. The switch mechanism 153 switches the transport path 150 to the first transport path 151 when the first determination unit 131 (see FIG. 4) determines that the paper is not worn, and switches the transport path 150 to the second transport path 152 when the first determination unit 131 determines that the paper is worn.

[0115] The third point is that measuring device 106 is provided on second conveying path 152. Measuring device 106 measures the characteristic values ​​of a sheet of paper in response to detecting the sheet of paper that has been conveyed. Since second conveying path 152 leads to paper output tray 142 to which sheets determined to be worn are discharged, in image forming apparatus 1A, measuring device 106 measures the characteristic values ​​of the sheet of paper only when the sheet of paper is determined to be worn.

[0116] The processing executed by the image forming apparatus in the third embodiment will be described with reference to Fig. 15. Fig. 15 is a diagram showing an example of the processing executed by the image forming apparatus in the third embodiment. The processing shown in Fig. 15 is an example of the processing executed when a print job including manuscript data consisting of N pages (N is an integer equal to or greater than 1) is executed. The processing shown in Fig. 15 is realized by processor 101 shown in Fig. 4 executing program 121 (see Fig. 4).

[0117] The process shown in Fig. 15 is similar to the process shown in Fig. 7, except that the process of receiving the measurement value (the process of step S4) is executed when it is determined that the paper is worn out (YES in step S6). The same step numbers are assigned to the processes shown in Fig. 15 that are similar to the processes shown in Fig. 7, and the description thereof will not be repeated.

[0118] First, processor 101 executes steps S1 to S3. Next, processor 101 executes step S5. Next, processor 101 executes step S6. If it is determined that the paper is worn out (YES in step S6), processor 101 executes step S4, and then proceeds to step S7. On the other hand, if it is determined that the paper is not worn out (NO in step S6), processor 101 proceeds to step S14. Note that the processing from step S7 onwards is as described in FIG. 7.

[0119] Thus, according to the third embodiment, when a sheet is determined to be worn out during execution of a print job, information including the characteristic values ​​(measurement values) of the sheet measured by the measuring device 106 is output to an output device such as the operation panel 107. This improves the efficiency of the user's work to eliminate the wear.

[0120] Furthermore, according to the third embodiment, the characteristic values ​​of the paper are measured only when the paper is determined to be worn. Although it takes a certain amount of time for measurement by the measuring device 106, according to the third embodiment, the measurement is performed only when the paper is determined to be worn, so that it is possible to prevent a decrease in the productivity of the image forming apparatus.

[0121] [Embodiment 4] In the fourth embodiment, when the paper is not determined to be worn, the measurement value is output to an output device such as an operation panel in response to a determination that a change has occurred in the density of the inspection image.

[0122] The image forming apparatus according to the fourth embodiment has the same configuration as the image forming apparatus 1 according to the first embodiment (see FIG. 1). The printer 104 (see FIG. 2) forms a test image on paper in addition to an image based on the manuscript data included in the print job. The paper on which the test image is formed may be the same paper as the paper on which the image based on the manuscript data included in the print job is formed, or it may be a different paper.

[0123] Here, the inspection image will be described with reference to Fig. 16. Fig. 16 is a diagram showing an example of an inspection image. In the example shown in Fig. 16, inspection image G1 is formed on the same paper as the paper on which an image based on the manuscript data included in the print job is formed. Inspection image G1 is an image for checking whether the density of each color of cyan, magenta, yellow, and black is appropriate. Image G2 is an image formed based on the manuscript data included in the print job.

[0124] Scanner 105 (see FIG. 4) scans a sheet of paper on which test image G1 is formed to acquire an image of the paper. A test image with an appropriate density as a correct image is stored in advance in storage device 120 (see FIG. 4). First determination unit 131 (see FIG. 4) compares the correct image with the image of the paper on which test image G1 is formed, acquired by scanner 105, to determine whether or not a change has occurred in the density of test image G1. A change in the density of test image G1 means that there is a difference of a predetermined value or more between the density of test image G1 and the density of the correct image. Continuing printing in this case may result in a failure to achieve the image quality intended by the user, and the paper may become worn out.

[0125] If the first judgment unit 131 does not judge the paper to be worn, and it is judged that a change has occurred in the density of the inspection image G1, the instruction unit 134 (see Figure 4) further instructs an output device such as the operation panel 107 to output the characteristic values ​​(measurement values) of the paper measured by the measurement device 106 (see Figure 4).

[0126] The processing executed by the image forming apparatus in the fourth embodiment will be described with reference to Fig. 17. Fig. 17 is a diagram showing an example of processing executed by the image forming apparatus in the fourth embodiment. The processing shown in Fig. 17 is an example of processing when a print job including manuscript data consisting of N pages (N is an integer equal to or greater than 1) is executed. The processing shown in Fig. 17 is realized by processor 101 shown in Fig. 4 executing program 121 (see Fig. 4).

[0127] The process shown in Fig. 17 is the same as the process shown in Fig. 7 except that the process of step S6B has been added. The same step numbers are assigned to the processes in Fig. 17 that are similar to the processes in Fig. 7, and descriptions thereof will not be repeated. Here, only step S6B will be described.

[0128] In step S6B, processor 101 determines whether a change has occurred in the density of the inspection image. If it is determined that a change has occurred in the density of the inspection image (YES in step S6B), processor 101 proceeds to step S7. On the other hand, if it is determined that no change has occurred in the density of the inspection image (NO in step S6B), processor 101 proceeds to step S14.

[0129] Thus, according to the fourth embodiment, when a paper sheet is determined to be worn out during execution of a print job, information including the characteristic values ​​(measurement values) of the paper sheet measured by the measuring device 106 is output to an output device such as the operation panel 107. This improves the efficiency of the user's work to eliminate the wear.

[0130] Furthermore, according to the fourth embodiment, if the paper is not determined to be worn, information including the paper characteristic values ​​(measurement values) measured by the measuring device 106 is output to an output device such as the operation panel 107 in response to a change in the density of the inspection image. If printing continues while a change in the density of the inspection image has occurred, the image quality intended by the user may not be achieved, and the paper may become worn. According to the fourth embodiment, if the paper is not determined to be worn, information including the paper characteristic values ​​(measurement values) measured by the measuring device 106 is output to an output device such as the operation panel 107 in response to a change in the density of the inspection image. An engineer can estimate which parts of the image forming device need to be adjusted based on the measurement values, and can make adjustments before wear occurs. Therefore, according to the fourth embodiment, it is possible to suppress the occurrence of wear.

[0131] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0132] 1,1A Image forming device, 81,82,83,84,G2 Image, 85,86 Icon, 99 Network, 100 Control device, 101 Processor, 102 Main memory, 103 Conveyor unit, 104 Printer, 104A Photosensitive member, 104B Intermediate transfer belt, 104C Secondary transfer unit, 104D Fuser unit, 105 Scanner, 105A, 105B Image sensor, 106 Measuring device, 107 Operation panel, 108 Communication interface, 109 Memory card interface, 109A Memory card, 119 Internal bus, 120 Storage device, 121 Program, 122 Print job, 123 Correct image, 124 Characteristics information table, 125 Tray information table, 131 First determination unit, 132 Estimation unit, 133 Second determination unit, 134 Instruction unit, 135 Transmission unit, 140, 141, 142 paper output tray, 150 transport path, 151 first transport path, 152 second transport path, 153 switch mechanism, 500 terminal device, D1, D2, D3, D4 screen, G1 inspection image, P1, P2 position, T paper feed tray.

Claims

1. an image forming unit that forms an image on a sheet transported through a transport path; a scanner for scanning the paper sheet conveyed along the conveyance path to acquire an image of the paper sheet; a measurement unit that measures a characteristic value of the paper transported along the transport path; a first determination unit that determines whether the paper is worn out or not based on the image acquired by the scanner; an instruction unit that instructs an output device to output information including a measurement value measured by the measurement unit when the paper is determined to be worn out during execution of a print job.

2. the image forming apparatus further includes an estimation unit that, when it is determined that the paper is worn, estimates a cause of the wear from the measurement value; The image forming apparatus according to claim 1 , wherein the information further includes a cause of the waste.

3. the image forming apparatus further includes a storage device that stores the characteristic values ​​of the paper by type of the paper; 3. The image forming apparatus according to claim 2, wherein when the paper is determined to be worn, the estimation unit estimates the cause of the wear by comparing the measurement value with the characteristic value corresponding to the type specified by the print job.

4. the characteristic value includes a value indicative of a first characteristic; The image forming apparatus of claim 3, wherein the estimation unit sets a value indicating the first characteristic among the characteristic values ​​corresponding to the type specified by the print job as a first threshold value, and if the value indicating the first characteristic among the measured values ​​exceeds the first threshold value, estimates that the cause of the waste is a different type of paper.

5. The image forming apparatus according to claim 4 , wherein the value indicating the first characteristic includes at least one of smoothness, basis weight, and paper thickness.

6. 6. The image forming apparatus according to claim 4, wherein the estimation unit estimates that the cause of the waste is something related to the image forming apparatus when a value indicating the first characteristic among the measured values ​​does not exceed the first threshold value.

7. the characteristic value further includes a value indicating a second characteristic different from the first characteristic; the value indicating the second property is water content; the image forming unit is a printer equipped with a fixing unit, the measuring unit is provided downstream of the fixing unit on the conveying path, The image forming apparatus of claim 6, wherein the estimation unit sets a value indicating the second characteristic among the characteristic values ​​corresponding to the type specified by the print job as a second threshold value, and when a value indicating the first characteristic among the measured values ​​does not exceed the first threshold value and a value indicating the second characteristic among the measured values ​​exceeds the second threshold value, the estimation unit estimates that the cause of the waste is the fixing temperature in the fixing unit among factors related to the image forming apparatus.

8. the image forming apparatus further includes a paper feed tray including a tray in which the paper determined to be worn out was stored and at least one other tray other than the tray in which the paper was stored, the storage device further stores the characteristic values ​​of the sheets accommodated in the paper feed trays as set values ​​for each tray; the image forming apparatus further comprises a second determination unit that, when it is estimated that the cause of the waste is the wrong type of paper, determines whether or not there is at least one other tray storing paper having characteristics corresponding to the type specified by the print job by setting the characteristic value corresponding to the type specified by the print job as a third threshold value and comparing the setting value corresponding to the at least one other tray with the third threshold value; An image forming apparatus according to any one of claims 3 to 7, wherein, when it is determined that there is at least one other tray containing paper having characteristics corresponding to the type specified by the print job, the information further includes a message prompting the user to feed paper from the other tray.

9. the image forming apparatus further includes a transmitting unit that transmits a signal to the measuring unit when the paper is determined to be worn out; The image forming apparatus according to any one of claims 1 to 8, wherein the measuring unit is provided downstream of the scanner on the conveying path, and measures the characteristic value of the conveyed paper in response to receiving the signal.

10. the transport path includes a first transport path leading to a first tray onto which sheets not determined to be worn are discharged, and a second transport path leading to a second tray onto which sheets determined to be worn are discharged, The image forming apparatus according to any one of claims 1 to 9, wherein the measuring unit is provided in the second transport path and measures the characteristic value of the paper in response to detecting the paper being transported.

11. the image forming unit further forms a test image on the same paper as the paper or on another paper different from the paper; the first determination unit further determines whether or not a change in density of the test image has occurred based on an image of the paper on which the test image has been formed, the image being acquired by the scanner; An image forming apparatus according to any one of claims 1 to 10, wherein the instruction unit further instructs the output device to output the measurement value when it is determined that a change has occurred in the density of the inspection image if the paper is not determined to be worn.

12. 1. A computer-implemented imaging method comprising: forming an image on a sheet conveyed through a conveyance path; acquiring an image of the paper by scanning the paper being transported along the transport path; acquiring characteristic values ​​of the paper transported through the transport path as measurement values; determining whether the paper is worn out or not based on the acquired image; and instructing an output device to output information including the acquired measurement value when the paper is determined to be worn out during execution of a print job.

Images