Image forming apparatus, control method for image forming apparatus, and control program for image forming apparatus

Abstract

To provide an image forming apparatus that can minimize a stop frequency of a print job when real-time adjustment is adopted.SOLUTION: An image forming apparatus of a roll-to-roll system comprises a control unit 100 having: a real-time adjustment function 101 to print an image for adjustment on roll paper and acquire a result of reading the image for adjustment from an image reading unit during execution of a print job, and perform, in real time, adjustment of an image forming condition in an image forming unit on the basis of the reading result; and an error time operation determination function 102 to, when detecting an adjustment error in the real-time adjustment function 101, determine whether to stop or continue the print job on the basis of a state of occurrence of the adjustment error.SELECTED DRAWING: Figure 10

Description

[Technical Field]

[0001] The present disclosure relates to an image forming apparatus, a control method for an image forming apparatus, and a control program for an image forming apparatus. [Background Art]

[0002] Conventionally, there has been known an image forming apparatus provided with a function (hereinafter also referred to as a "real-time adjustment function") that prints an adjustment patch separately from an image to be printed on a recording medium while a print job is being executed, reads the adjustment patch with an in-line sensor, and adjusts image forming conditions in an image forming unit in real time based on the reading result (see, for example, Patent Document 1).

[0003] In real-time adjustment, an adjustment patch (hereinafter also referred to as an "adjustment image") is printed on all pages in the margin area of a sheet, read by an image sensor such as a CCD mounted on a post-processing device to calculate a correction value, and the calculated value is applied to an image being printed, thereby stabilizing the color of the image forming apparatus. Note that adjustment items in real-time adjustment include gradation correction, density correction, color unevenness correction, and the like.

[0004] FIG. 1 is a diagram showing an example of an adjustment patch attached to a sheet in the real-time adjustment function. In FIG. 1, as an example of the adjustment patch, a patch composed of images of each color of YMCK and images of each color of RGBPb (Pb: black formed by superimposing YMC) is shown. The patch area is formed, for example, in an edge area separate from the original image forming area on the sheet, and is finally cut using a cutter.

[0005] In this type of image forming apparatus, if the required correction amount for the adjustment target in real-time adjustment exceeds a certain threshold, the system recognizes that an adjustment error (hereinafter simply referred to as "adjustment error") has occurred without performing real-time adjustment. When this type of adjustment error is detected, in sheet-fed image forming apparatuses, the paper being printed is usually ejected to the sub-tray, the job is interrupted, and reprinting is performed from the point where the adjustment error occurred. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2018-010115 [Overview of the project] [Problems that the invention aims to solve]

[0007] Incidentally, there is a known type of image forming apparatus (see Figure 3) that uses roll paper as a recording medium and forms an image on the roll paper.

[0008] In roll-to-roll image forming machines, even if a print job (i.e., the image forming process) is interrupted, the paper transport itself cannot be stopped because the paper (i.e., the roll paper) passes through the fuser inside the machine. This creates a problem where blank areas are created in the paper equal to the distance the paper has been transported while the print job is stopped.

[0009] Figure 2 shows an example of a blank area that occurs in a roll of paper after printing. Generally, rolls of paper with blank areas are considered defective (for example, if the printing target is a label as shown in Figure 2, a shift in the label formation position occurs midway through printing, resulting in misalignment of the label when it is applied to a PET bottle or other item using a labeling machine). Therefore, if a blank area occurs in a roll of paper, workers at the worksite will need to manually cut out the blank area from the roll and then join the ends of the blank area together, which will lead to a decrease in production efficiency.

[0010] In other words, in a roll-to-roll image forming apparatus, if the operation control is performed to temporarily suspend the print job each time an adjustment error is detected in real-time adjustment, as in a sheet-fed image forming apparatus, there is a problem in that many blank areas are formed in the printed roll paper (hereinafter also referred to as "product roll paper") as the final product.

[0011] The present invention has been made in view of the above problems, and aims to provide a roll-to-roll type image forming apparatus, a control method for the image forming apparatus, and a control program for the image forming apparatus that can minimize the frequency of print job stoppages when real-time adjustment is applied. [Means for solving the problem]

[0012] The main present invention that solves the aforementioned problems is: A roll-to-roll type image forming apparatus, An image forming unit having an image carrier that holds toner, and printing an image formed by exposure and development processing on the image carrier onto roll paper, An image reading unit that reads the image formed on the roll paper, The system includes a control unit that controls the image forming unit based on a print job that has received an execution command, The control unit, A real-time adjustment function that, while the print job is being executed, prints an adjustment image onto the roll paper, obtains the reading result of the adjustment image from the image reading unit, and adjusts the image forming conditions in the image forming unit in real time based on the reading result, The real-time adjustment function has an error-response operation determination function that, when it detects an adjustment error indicating a failure in the adjustment, determines whether to stop or continue the print job based on the circumstances of the adjustment error. It is an image forming apparatus.

[0013] Also, in other situations, A control method for a roll-to-roll type image forming apparatus, While a print job is running, an adjustment image is printed on roll paper, and the reading result of the adjustment image is obtained from the image reading unit. Based on the reading result, the image forming conditions in the image forming unit are adjusted in real time. If an adjustment error indicating a failure in the adjustment is detected, the system will decide whether to stop or continue the print job based on the circumstances of the adjustment error. This is a control method.

[0014] Also, in other situations, A control program for a roll-to-roll type image forming apparatus, While a print job is running, an adjustment image is printed on roll paper, and the reading result of the adjustment image is obtained from the image reading unit. Based on the reading result, the image forming conditions in the image forming unit are adjusted in real time. If an adjustment error indicating a failure in the adjustment is detected, the system will decide whether to stop or continue the print job based on the circumstances of the adjustment error. This is a control program. [Effects of the Invention]

[0015] According to the image forming apparatus of the present invention, it is possible to minimize the frequency of print job stoppages and reduce the amount of blank space generated in the printed roll paper. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] [Figure 1] A diagram illustrating an example of an adjustment patch applied to a sheet in a real-time adjustment function [Figure 2] A diagram illustrating an example of a blank area generated in rolled paper after printing [Figure 3] A diagram schematically illustrating the overall configuration of an image forming apparatus according to an embodiment of the present invention [Figure 4] A diagram illustrating the configuration of a control system of an image forming unit included in the image forming apparatus according to an embodiment of the present invention [Figure 5] A diagram illustrating the functional configuration of a control unit according to an embodiment of the present invention [Figure 6] A diagram illustrating an example of an operation screen for setting a determination mode to be applied when an adjustment error is detected in the image forming apparatus according to an embodiment of the present invention [Figure 7] A diagram illustrating an example of a display screen that enables browsing of an error history of adjustment errors in the image forming apparatus according to an embodiment of the present invention [Figure 8] A diagram illustrating an example of an error position indication mark printed on rolled paper in the image forming apparatus according to an embodiment of the present invention [Figure 9] A diagram illustrating an example of an operation screen displayed after completion of a currently executed print job and before start of a next print job in the image forming apparatus according to an embodiment of the present invention [Figure 10] A flowchart illustrating an example of an operation performed by a control unit when an adjustment error is detected in the image forming apparatus according to an embodiment of the present invention MODES FOR CARRYING OUT THE INVENTION

[0017] Preferred embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. In the present specification and the drawings, components having substantially the same functions are denoted by the same reference numerals, and redundant description thereof is omitted.

[0018] [Overall configuration of the image forming apparatus] Hereinafter, with reference to Figures 3 to 4, an example of the configuration of an image forming apparatus (hereinafter referred to as "image forming apparatus U") according to one embodiment of the present invention will be described.

[0019] Figure 3 is a schematic diagram showing the overall configuration of the image forming apparatus U according to this embodiment. Figure 4 is a diagram showing the configuration of the control system of the image forming unit 1 included in the image forming apparatus U according to this embodiment.

[0020] The image forming apparatus U is a roll-to-roll type image forming apparatus that uses a roll of paper P as a recording medium and forms an image on the roll of paper P. As shown in Figure 3, the image forming apparatus U is configured by connecting a paper feeding unit 2, an image forming unit 1, and a winding unit 3 from the upstream side along the transport direction of the roll of paper P.

[0021] The paper feeding unit 2 is a device that feeds roll paper P to the image forming unit 1. Inside the housing of the paper feeding unit 2, the roll paper P is wound in a roll shape around a paper feeding roller 2a and held rotatably. The paper feeding unit 2 transports the roll paper P wound around the paper feeding roller 2a to the image forming unit 1 at a constant speed, for example, via multiple transport roller pairs. The paper feeding operation of the paper feeding unit 2 is controlled by the control unit 100 provided in the image forming unit 1. The paper feeding unit 2 also has an optical sensor 2b that detects the thickness from the axis of the paper feeding roller 2a to the outermost part of the wound roll paper P.

[0022] The image forming unit 1 forms a color image using electrophotographic process technology. Specifically, the image forming unit 1 first transfers the toner images of each toner color—Y (yellow), M (magenta), C (cyan), and K (black)—formed on the photoreceptor drum 413 to an intermediate transfer belt 421, superimposes the four toner images on the intermediate transfer belt 421, and then secondarily transfers them to the roll paper P fed from the paper feeding unit 2, thereby forming a color image on the roll paper P.

[0023] Furthermore, the image forming unit 1 employs a tandem system in which photoreceptor drums 413 corresponding to four colors, Y, M, C, and K, are arranged in series in the direction of travel of the intermediate transfer belt 421, and the toner images of each toner color are sequentially transferred to the intermediate transfer belt 421 in a single step.

[0024] As shown in Figure 4, the image forming unit 1 comprises an image reading unit 10, an operation display unit 20, an image processing unit 30, an image forming unit 40, a paper transport unit 50, a fixing unit 60, an inline scanner 70, a communication unit 81, a storage unit 82, and a control unit 100.

[0025] The control unit 100 includes a CPU (Central Processing Unit) 100a, a ROM (Read Only Memory) 100b, a RAM (Random Access Memory) 100c, etc. The CPU 100a reads a program corresponding to the processing content from the ROM 100b, loads it into the RAM 100c, and works in cooperation with the loaded program to centrally control the operation of each block of the image forming unit 1. At this time, various data stored in the storage unit 82 are referenced. The storage unit 82 is composed of, for example, a non-volatile semiconductor memory (so-called flash memory) or a hard disk drive.

[0026] The control unit 100 transmits and receives various types of data to and from external devices (e.g., personal computers (not shown)) connected to a communication network such as a LAN (Local Area Network) or WAN (Wide Area Network) via the communication unit 81. For example, the control unit 100 receives image data (input image data) transmitted from an external device and forms an image on the roll paper P based on this image data. The communication unit 81 is composed of a communication control card, such as a LAN card.

[0027] As shown in Figure 3, the image reading unit 10 is configured to include an automatic document feeder 11 called an ADF (Auto Document Feeder) and a document image scanning device 12 (scanner), etc.

[0028] The automatic document feeder 11 transports the documents D placed in the document tray using a transport mechanism and sends them to the document image scanner 12. The automatic document feeder 11 makes it possible to continuously scan images (including both sides) of multiple documents D placed in the document tray all at once.

[0029] The document image scanning device 12 optically scans a document transported from the automatic document feeder 11 onto the contact glass or a document placed on the contact glass, and images the reflected light from the document onto the light-receiving surface of the CCD (Charge Coupled Device) sensor 12a to read the document image. The image reading unit 10 generates input image data based on the reading result by the document image scanning device 12. This input image data is subjected to predetermined image processing by the image processing unit 30.

[0030] As shown in Figure 3, the operation display unit 20 is composed of, for example, a liquid crystal display (LCD) with a touch panel, and functions as a display unit 21 and an operation unit 22. The display unit 21 displays various operation screens, image status, operating status of each function, printing information, etc., according to display control signals input from the control unit 100. The operation unit 22 is equipped with various operation keys such as a numeric keypad and a start key, accepts various input operations from the user, and outputs operation signals to the control unit 100.

[0031] The image processing unit 30 includes circuits and other components that perform digital image processing on the input image data according to initial settings or user settings. For example, under the control of the control unit 100, the image processing unit 30 performs gradation correction based on gradation correction data (gradation correction table). In addition to gradation correction, the image processing unit 30 also performs various correction processes such as color correction and shading correction, as well as compression processing, on the input image data. The image forming unit 40 is controlled based on the image data that has undergone these processes.

[0032] As shown in Figure 3, the image forming unit 40 includes toner image forming units 41Y, 41M, 41C, 41K, and an intermediate transfer unit 42, etc., for forming an image using colored toners for the Y, M, C, and K components based on the input image data.

[0033] The toner image forming units 41Y, 41M, 41C, and 41K for the Y, M, C, and K components have similar configurations. For the convenience of illustration and explanation, common components are indicated by the same reference numeral, and when distinguishing them, Y, M, C, or K is added to the reference numeral. In Figure 3, only the components of the toner image forming unit 41Y for the Y component are given reference numerals, while the components of the other toner image forming units 41M, 41C, and 41K are omitted.

[0034] The toner image forming unit 41 includes an exposure device 411, a developing device 412, a photoreceptor drum 413, a charging device 414, a drum cleaning device 415, and a toner recovery unit 200, etc.

[0035] The photoreceptor drum 413 is made of an organic photoreceptor, for example, in which a photosensitive layer made of a resin containing an organic photoconductor is formed on the outer surface of a drum-shaped metal substrate. The control unit 100 rotates the photoreceptor drum 413 at a constant peripheral speed by controlling the drive current supplied to the drive motor (not shown) that rotates the photoreceptor drum 413.

[0036] The charging device 414 is, for example, a charging charger, which uniformly charges the surface of the photoconductive photoreceptor drum 413 to a negative polarity by generating a corona discharge.

[0037] The exposure apparatus 411 is composed of, for example, a semiconductor laser, and irradiates the photoreceptor drum 413 with laser light corresponding to the image of each toner color component. As a result, an electrostatic latent image of each toner color component is formed in the image region of the surface of the photoreceptor drum 413 that has been irradiated with laser light, due to the potential difference with the background region.

[0038] The developing device 412 is a two-component inverted developing device that visualizes the electrostatic latent image and develops it as a toner image by depositing the developer of each toner color component onto the surface of the photoreceptor drum 413.

[0039] The developing roller 412A of the developing device 412 carries the developer while rotating and supplies the toner contained in the developer to the photoreceptor drum 413. Specifically, the developing roller 412A receives a developing bias from the developing bias application unit 412B, and a potential difference is generated between it and the surface of the photoreceptor drum 413, thereby forming a toner image on the surface of the photoreceptor drum 413.

[0040] The drum cleaning device 415 has an elastic, flat drum cleaning blade or the like that is in contact with the surface of the photoreceptor drum 413, and removes toner that remains on the surface of the photoreceptor drum 413 without being transferred to the intermediate transfer belt 421.

[0041] The intermediate transfer unit 42 includes an intermediate transfer belt 421, a primary transfer roller 422, a plurality of support rollers 423, a secondary transfer roller 424, and a belt cleaning device 426, etc.

[0042] The intermediate transfer belt 421 is an endless belt and is stretched in a loop around a plurality of support rollers 423. At least one of the plurality of support rollers 423 is a drive roller, and the others are driven rollers. For example, it is preferable that the roller 423A, which is located downstream in the belt travel direction from the primary transfer roller 422 for component K, is the drive roller. This makes it easier to maintain a constant belt travel speed in the primary transfer section. As the drive roller 423A rotates, the intermediate transfer belt 421 travels at a constant speed in the direction of arrow A.

[0043] The intermediate transfer belt 421 is a conductive and elastic belt with a high-resistance layer on its surface. The intermediate transfer belt 421 is rotationally driven by a control signal from the control unit 100.

[0044] The primary transfer roller 422 is positioned on the inner circumferential side of the intermediate transfer belt 421, facing the photoreceptor drum 413 for each toner color component. By pressing the primary transfer roller 422 against the photoreceptor drum 413 with the intermediate transfer belt 421 in between, a primary transfer nip is formed for transferring the toner image from the photoreceptor drum 413 to the intermediate transfer belt 421.

[0045] The secondary transfer roller 424 is positioned on the outer circumferential side of the intermediate transfer belt 421, opposite the backup roller 423B which is located downstream of the drive roller 423A in the belt travel direction. By pressing the secondary transfer roller 424 against the backup roller 423B with the intermediate transfer belt 421 in between, a secondary transfer nip is formed for transferring the toner image from the intermediate transfer belt 421 to the roll paper P.

[0046] As the intermediate transfer belt 421 passes over the primary transfer nip, the toner image on the photoreceptor drum 413 is sequentially superimposed onto the intermediate transfer belt 421 and primary transferred. Specifically, by applying a primary transfer bias to the primary transfer roller 422 and applying a charge with the opposite polarity to the toner to the back side of the intermediate transfer belt 421, that is, the side in contact with the primary transfer roller 422, the toner image is electrostatically transferred to the intermediate transfer belt 421.

[0047] Subsequently, as the roll paper P passes through the secondary transfer nip, the toner image on the intermediate transfer belt 421 is secondary transferred to the roll paper P. Specifically, a secondary transfer bias is applied to the secondary transfer roller 424, and a charge with the opposite polarity to the toner is applied to the back side of the roll paper P, that is, the side in contact with the secondary transfer roller 424, thereby electrostatically transferring the toner image to the roll paper P. The roll paper P, on which the toner image has been transferred, is then transported toward the fuser unit 60.

[0048] The belt cleaning device 426 removes residual transfer toner remaining on the surface of the intermediate transfer belt 421 after secondary transfer. Alternatively, instead of the secondary transfer roller 424, a so-called belt-type secondary transfer unit may be used, in which the secondary transfer belt is stretched in a loop between multiple support rollers, including the secondary transfer roller.

[0049] The fixing unit 60 comprises an upper fixing unit 60A having a fixing surface side member positioned on the fixing surface of the roll paper P, i.e., the side on which the toner image is formed; a lower fixing unit 60B having a back side support member positioned on the back side of the roll paper P, i.e., the side opposite the fixing surface; and a heating source, etc. When the back side support member is pressed against the fixing surface side member, a fixing nip is formed that grips and transports the roll paper P. The fixing unit 60 fixes the toner image to the roll paper P by heating and pressurizing the transported roll paper P with the fixing nip after the toner image has been secondarily transferred.

[0050] The inline scanner 70 (corresponding to the "image reading unit" of the present invention) captures and reads images of adjustment patches formed on the roll paper P using, for example, a built-in CCD sensor (Charge Coupled Device) or CMOS sensor (Complementary Metal Oxide Semiconductor). The inline scanner 70 is positioned, for example, downstream of the fixing unit 60 in the transport path unit 53, facing the roll paper P. Furthermore, the inline scanner 70 is capable of capturing images in each wavelength band of RGB, for example.

[0051] The paper transport unit 50 includes a paper feeding unit 51, a paper discharge unit 52, and a transport path unit 53, etc. The transport path unit 53 has multiple transport roller pairs and transports the roll paper P fed from the paper feeding unit 2 to the image forming unit 40 and the fixing unit 60, and then sends it to the take-up unit 3. The multiple transport roller pairs of the transport path unit 53 include registration roller pairs that correct the tilt and misalignment of the roll paper P.

[0052] Furthermore, the paper feed section 51 is a separate paper feed section for plain paper, provided separately from the paper feed unit 2, and feeds paper that does not exceed the width of the main body of the image forming unit 1. The three paper feed tray units that make up the paper feed section 51 store paper identified based on basis weight, size, etc., according to pre-set types.

[0053] The roll paper P fed from the paper feeding unit 2 to the image forming unit 1 is transported to the image forming unit 40 by the transport path section 53. In the image forming unit 40, the toner image from the intermediate transfer belt 421 is transferred to one side of the roll paper P in a single secondary transfer, and a fixing process is performed in the fixing unit 60. The image-formed roll paper P is transported to the winding unit 3 by the paper discharge section 52, which is equipped with a pair of transport rollers.

[0054] The winding unit 3 is a device that winds up the roll paper P that has been transported from the image forming unit 1. Inside the housing of the winding unit 3, for example, the roll paper P is wound around the paper discharge roller 3a and held in a roll shape. That is, the winding unit 3 winds the roll paper P that has been transported from the image forming unit 1 onto the paper discharge roller 3a at a constant speed, passing through multiple transport roller pairs. The winding unit 3 also has an optical sensor 3b that detects the thickness from the axis of the paper discharge roller 3a to the outermost part of the winding roll paper P.

[0055] [Detailed configuration of the control unit 100] Figure 5 shows the functional configuration of the control unit 100 according to this embodiment.

[0056] The control unit 100 includes a real-time adjustment function 101, an error operation determination function 102, an error history display function 103, and an error mark printing function 104.

[0057] The real-time adjustment function 101 is a function that, while a print job is being executed (i.e., while printing is being performed on the roll paper P), prints adjustment patches on the margin area of ​​the roll paper P, obtains the reading result of the adjustment patches from the inline scanner 70, and adjusts the image formation conditions in the image formation unit 40 in real time based on the reading result.

[0058] The method by which the real-time adjustment function 101 adjusts the image formation conditions is the same as, for example, the method relating to the prior art (see, for example, Patent Document 1). The real-time adjustment function 101 calculates adjustment values ​​(correction values) for gradation correction based on the reading results of the adjustment patch, and corrects the charging bias of the charging device 414 of the image formation unit 40, the exposure light amount and exposure position of the exposure device 411, or the development bias of the development device 412, thereby preventing changes in the image during the execution of the print job and stabilizing the colors. Here, gradation correction is given as an example of the adjustment items in the real-time adjustment function 101, but the real-time adjustment function 101 may also perform density correction or color unevenness correction.

[0059] The adjustment patch is, for example, a pattern of images of each color in YMCK and each color in RGBPb (Pb = black formed by superimposing YMC), similar to the one described in Figure 1. The real-time adjustment function 101 forms adjustment patches in predetermined margin areas on each page of the roll paper P so that, for example, tonal shifts of each color that occur while a print job is being executed can be detected.

[0060] The error operation determination function 102 is a function that, when it detects an adjustment error in the real-time adjustment function 101, decides whether to stop or continue the currently running print job based on the circumstances of the adjustment error.

[0061] In general, adjustment errors in real-time adjustment can occur due to various factors. These include periodic phenomena caused by dirt on the transport rollers or intermediate transfer belt, as well as sudden and temporary phenomena caused by toner spills from the developing unit. Adjustment errors can also occur due to user setting errors (for example, incorrect paper size settings). Furthermore, the nature of these errors can range from serious issues that significantly affect the overall image quality of the printed image to minor or one-off errors that do not greatly affect the image quality, such as errors in the margins.

[0062] In this regard, as mentioned above, from the perspective of suppressing the insertion of blank areas into the printed image of the product roll paper, some users have a desire to continue printing without stopping when an adjustment error is detected, especially if the cause of the adjustment error is temporary or minor (i.e., the detected adjustment error has little impact on subsequent printing).

[0063] However, as described above, there are various causes of adjustment errors, so it is not possible to uniquely identify the cause of the error based solely on the image information of the adjustment patch (for example, abnormal image density or image breakage within the adjustment patch). Therefore, after careful consideration, the inventors of this application have adopted a configuration that determines whether to stop or continue the currently running print based on the detected adjustment error. This is based on the inventors' new finding that it is possible to estimate the impact of the detected adjustment error's cause on subsequent printing based on the detected adjustment error's occurrence.

[0064] In other words, in the image forming apparatus U according to this embodiment, the frequency of temporarily stopping the printing operation of the image forming apparatus U is minimized by deciding whether to stop or continue the currently running print based on the detected adjustment error. This prevents the formation of unnecessary blank areas in the product roll paper.

[0065] Specifically, the conditions for which the error-causing operation determination function 102 determines the occurrence of adjustment errors include the timing of the adjustment error or the frequency of the adjustment error. More precisely, as described later, the error-causing operation determination function 102 identifies the conditions for the adjustment error based on the image formation distance taken between the start of the print job and the detection of the adjustment error, and the number of times adjustment errors have been detected since the start of the print job.

[0066] In this embodiment, if an adjustment error is detected while a print job is being executed, the error-response operation determination function 102 applies one or more of the following determination modes from the first to the fourth determination modes to identify the timing or frequency of the adjustment error, and decides whether to stop or continue the currently running print job.

[0067] First, the error operation determination function 102 controls the operation of the image forming apparatus U such that if an adjustment error is detected when the image formation distance to the roll paper P in the print job (i.e., the image formation distance from the start of the print job to the present time) is less than the first threshold, the print job is stopped, and if an adjustment error is detected when the image formation distance to the roll paper P in the print job is equal to or greater than the first threshold, the print job is continued (hereinafter referred to as the "first determination mode").

[0068] The image formation distance to the roll paper P in a print job is one indicator used to measure the printing time from the start of printing until an adjustment error is detected. The first threshold mentioned above can be set to, for example, the distance at which the image formation distance to the roll paper P corresponds to the beginning of the print job. In this case, the image formation distance to the roll paper P may be set as the number of pages or as an actual distance.

[0069] For example, if an adjustment error is detected on the first page of a print job, the cause of the adjustment error is likely to be an error in the user's print settings (for example, the roll paper size set in the user's print settings is different from the roll paper size installed in the device). Also, even if it is not on the first page of a print job, if an adjustment error is detected at the beginning of the print job, the cause of the adjustment error is likely to be something that frequently causes adjustment errors (for example, dirt on the transport roller or intermediate transfer belt). In this case, the cause of the error is likely to significantly affect the overall image quality of the printed image, and if printing continues as is, the roll paper itself may become a waste product.

[0070] On the other hand, if an adjustment error is detected during a print job after the image formation distance on the roll paper P has reached a predetermined distance (for example, near the last page), the cause of the adjustment error is likely to be temporary or infrequent (for example, toner spillage from the developing unit). In such cases, the real-time adjustment function tends to recover immediately after the adjustment error is detected, so the cause of the error is unlikely to significantly affect the overall image quality of the printed image. The first judgment mode is set based on this perspective.

[0071] Furthermore, the error operation determination function 102 controls the operation of the image forming apparatus U such that if an adjustment error is detected when the amount of roll paper P wrapped around the paper output roller 3a is less than the second threshold, the print job is stopped, and if an adjustment error is detected when the amount of roll paper P wrapped around the paper output roller 3a is equal to or greater than the second threshold, the print job is continued (hereinafter referred to as the "second determination mode").

[0072] Furthermore, the second threshold mentioned above is set to, for example, the amount of roll paper P wound around the paper discharge roller 3a that corresponds to the beginning of the print job (for example, 10 roll paper windings). The amount of roll paper P wound around the paper discharge roller 3a is determined, for example, by an optical sensor 3b (see Figure 3) that detects the thickness from the axis of the paper discharge roller 3a to the outermost part of the winding roll paper.

[0073] Furthermore, the error operation determination function 102 controls the operation of the image forming apparatus U such that if an adjustment error is detected when the remaining amount of roll paper P wrapped around the paper feed roller 2a is greater than or equal to the third threshold, the print job is stopped, and if an adjustment error is detected when the remaining amount of roll paper P wrapped around the paper feed roller 2a is less than the third threshold, the print job is continued (hereinafter referred to as the "third determination mode").

[0074] Furthermore, the third threshold mentioned above is set to, for example, the amount of roll paper P wound around the paper feed roller 2a that corresponds to the beginning of the print job (for example, 10 turns of paper being fed from the paper feed roller 2a). The amount of roll paper P wound around the paper feed roller 2a is determined, for example, by an optical sensor 2b (see Figure 3) that detects the thickness from the core of the paper feed roller to the outermost part of the roll paper P wound around it.

[0075] The amount of roll paper P wound around the output roller 3a (second judgment mode) and the remaining amount of roll paper P wound around the feed roller 2a (third judgment mode) are both indicators used to measure the printing time from the start of printing until an adjustment error is detected, similar to the image formation distance on the roll paper P in a print job (first judgment mode).

[0076] However, generally, in the image forming apparatus U, depending on the user settings, it is possible to divide a single print job into multiple short jobs and execute printing. In such cases, the print jobs being executed are switched sequentially, so it is not possible to accurately determine the frequency of adjustment errors based on the image formation distance on the roll paper P in the currently executing print job, as in the first judgment mode. In the second and third judgment modes, from this perspective, the occurrence of the adjustment error is identified based on the amount of roll paper P wound around the output roller 3a or the remaining amount of roll paper P wound around the feed roller, instead of the image formation distance on the roll paper P in the print job.

[0077] The reason why the second and third judgment modes are provided separately is to allow users to set a judgment mode that better matches their usage of the image forming apparatus U. For example, depending on the size of the roll paper P to be printed (e.g., the number of turns of the roll paper P) and the print distance for the judgment criterion regarding the continuation of the job stoppage (e.g., whether it is the beginning or end of the print job), when estimating the printing time from the start of printing until an adjustment error is detected, it may be better to use the amount of roll paper loaded on the output roller 3a as an indicator, or to use the remaining amount of roll paper wound on the feed roller 2a as an indicator. Furthermore, some users may print by sequentially splicing together the roll paper P wound around the paper feed roller 2a, or by cutting the roll paper P wound around the paper output roller 3a midway through printing. In such cases, when identifying the cause of an adjustment error, it may be better to use the amount of roll paper loaded around the paper output roller 3a as an indicator, or to use the remaining amount of roll paper wound around the paper feed roller 2a as an indicator.

[0078] Furthermore, the error operation determination function 102 controls the operation of the image forming apparatus U such that if the number of adjustment errors detected since the start of the print job exceeds the fourth threshold, the print job is stopped, and if the number of adjustment errors detected since the start of the print job is less than the fourth threshold, the print job is continued (hereinafter referred to as the "fourth determination mode").

[0079] Furthermore, the number of times an adjustment error is detected since the start of a print job (Fourth Judgment Mode) is an indicator of the frequency of adjustment errors. Normally, if the number of times an adjustment error is detected exceeds a predetermined number, it is highly likely that the cause of the adjustment error is serious, resulting from damage, abnormality, or other defects in the developing unit, exposure unit, transport roller, or intermediate belt. In such cases, the image quality of the printed image will deteriorate significantly, and the impact will extend over a wide area of ​​the printed product roll paper. It may also lead to a worsening of the abnormality or damage to the main unit of the device. The Fourth Judgment Mode is a judgment mode provided from this perspective.

[0080] The fourth threshold mentioned above is set to an appropriate value based on empirical rules. In addition, in the fourth judgment mode, the number of times an adjustment error is detected per unit time may be used as an indicator instead of the number of times an adjustment error is detected since the start of the print job.

[0081] As described above, the error operation determination function 102 according to this embodiment has multiple determination modes for determining whether to stop or continue the currently running print, taking into account various usage patterns of the image forming apparatus U by the user. However, the error operation determination function 102 may be equipped with only one of the first to fourth determination modes described above.

[0082] Figure 6 shows an example of an operation screen for setting the judgment mode to be applied when an adjustment error is detected. The operation screen in Figure 6 is displayed on the operation display unit 20 in a manner that allows the user to select an option, for example, before executing a print job.

[0083] In the operation screen shown in Figure 6, icons are displayed for changing the judgment mode applied when an adjustment error is detected. These icons relate to: "Behavior when an adjustment error occurs" (R11), "Stop error detection at job start" (R12), "Stop error detection when job resume" (R13), "Stop error detection based on the amount of paper loaded on the output roller" (R14), "Stop error detection based on the amount of paper remaining on the feed roller" (R15), and "Stop when errors are detected consecutively" (R16). On this operation screen, the user can select whether or not to apply each item by selecting from these icons R11 to R16.

[0084] Icon R11, which relates to "behavior during adjustment errors," is used to configure the operation of the image forming apparatus U when an adjustment error is detected. The user can select one of the following options: "automatic stop," "do not stop," or "always stop." If "automatic stop" is selected, the image forming apparatus U will apply the judgment mode set by icons R12 to R16 to automatically decide whether to stop or continue the print job based on the error situation.

[0085] Icons R12 to R16 are used to select the judgment mode to apply when "Automatic Stop" is selected, and correspond to icons for selecting which of the above-mentioned judgment modes 1 through 4 should be applied.

[0086] Icon R12, which relates to "Stopping Error Detection at Job Start," is used to set the "Enabled" / "Disabled" status of the first judgment mode described above. Icon R13, which relates to "Stopping Error Detection When Resuming a Job," is used to set whether to "enable" or "disable" the above-mentioned first judgment mode when resuming a job. Icon R14, which relates to "Error detection stop based on paper output roller load," is used to set the "enabled" or "disabled" status of the second judgment mode described above. Icon R15, which relates to "Error detection stop due to remaining paper feed roller amount," is used to set the "enabled" or "disabled" status of the third judgment mode described above. Icon R16, which relates to "Stop when errors are detected consecutively," is used to set the "Enable" / "Disable" status of the fourth judgment mode described above. Furthermore, the threshold values ​​for the judgment criteria in each of the judgment modes from the first to the fourth judgment modes can be changed by the user.

[0087] Here, the error operation determination function 102 can, for example, set only one of the first to fourth determination modes to "enabled". However, from a fail-safe perspective, it is also possible to set multiple determination modes from the first to fourth determination modes to "enabled". In this case, if the error operation determination function 102 determines to stop printing in the determination process of one of the multiple determination modes, it is preferable to stop printing regardless of the determination results of the other determination modes.

[0088] As shown in Figure 6, the error operation determination function 102 according to this embodiment is configured so that the user can change which of the above-mentioned determination modes to apply through user settings. This allows the user to select a determination mode that takes into account the usage of the image forming apparatus U, thereby enabling more accurate identification of the occurrence of adjustment errors. In other words, this makes it possible to stop the operation of the image forming apparatus U only when the impact on the printed image of the product roll paper is significant, thereby preventing unnecessary shutdown of the image forming apparatus U.

[0089] The above describes the judgment process when an adjustment error is detected by the error operation judgment function 102. However, if an adjustment error is detected during real-time adjustment and the print job is allowed to continue without stopping, it is also important to implement measures to prompt the user to perform maintenance on the image forming apparatus U or to inspect the printed product roll paper.

[0090] From this perspective, the error operation determination function 102 may, for example, if it continues a print job when an adjustment error is detected, temporarily suspend the operation of the image forming apparatus U when the print job is completed, without executing the next print job scheduled to follow the said print job. In this case, a blank area will occur in the printed image on the product roll paper, but since this is at the boundary of the print job, the impact on the overall printed image on the product roll paper is relatively small. In addition, the insertion of a blank area at the boundary of a print job may be permitted. By repairing the device condition that caused the real-time adjustment error at this timing, it is possible to suppress the recurrence of the error in subsequent print jobs.

[0091] Figure 7 shows an example of the operation screen displayed on the operation display unit 20 after the currently running print job has finished and before the next print job has started, when a print job is continued despite an adjustment error being detected.

[0092] The operation screen in Figure 7 displays, for example, an icon (R30) asking whether to start the next print job ("Yes" or "No" in Figure 7), allowing the user to issue a command to continue the job. The error operation determination function 102, when "Yes" is selected on the operation screen in Figure 7 (i.e., a command to continue the job), starts the execution of the next print job, for example. When "No" is selected, it displays, for example, the real-time adjustment error history (see Figure 8).

[0093] This allows users to review the details of any adjustment errors or inspect the product roll paper after the print job is completed.

[0094] The error history display function 103, when an adjustment error is detected by the error operation determination function 102 and the print job continues, stores the history of the detected adjustment error and displays the history on the operation display unit 20, etc. For example, when the print job is completed, the error history display function 103 displays an error history display screen on the operation display unit 20 as shown in Figure 8.

[0095] Figure 8 shows an example of a display screen that allows viewing of the error history of adjustment errors. In Figure 8, as an example of the error history display screen R20, the job name of the print job in which the adjustment error was detected, the print distance since the start of the print job at the time the adjustment error was detected, the stop status at the time the adjustment error was detected (i.e., whether the printing operation was stopped or continued), and the type of adjustment error are displayed in association with each other.

[0096] This allows users to review the details of any adjustment errors or inspect the product roll paper after the print job is completed.

[0097] The error history display function 103, for example, when an adjustment error is detected, stores in the memory unit (e.g., RAM 100c) the print distance since the start of the print job at the time the adjustment error was detected, the stop status at the time the adjustment error was detected (i.e., whether the printing operation was stopped or continued), and the type of adjustment error. Based on this data, it generates a display screen related to the error history of the adjustment error.

[0098] Although not shown in Figure 5, the control unit 100 may also have an error notification function in place of / with the error history display function 103, or together with this function, to notify the user if an adjustment error was detected during printing on the roll paper P when the printed roll paper P is replaced. The image forming apparatus U normally monitors whether the roll paper P has been replaced using a sensor (not shown) that detects whether the roll paper P is attached to the paper discharge roller 3a, and the error notification function notifies the user of the adjustment error based on this sensor information, for example.

[0099] This also allows users to review adjustment errors or inspect the product roll paper after the print job is complete.

[0100] The error mark printing function 104 is a function that, when it detects an adjustment error during real-time adjustment, prints a predetermined mark (hereinafter referred to as the "error mark") on the roll paper P to indicate the location within the roll paper P that caused the adjustment error.

[0101] Figure 9 shows an example of an error mark printed on roll paper P. In Figure 9, a bar-shaped error mark PM is shown formed in the margin area of ​​the original image forming area P10 together with adjustment patches P20a and P20b.

[0102] The error mark printing function 104 controls, for example, the image forming unit 40 to print an error mark on the roll paper P along with the original image and adjustment patch when printing to the roll paper P.

[0103] However, in this case, the timing at which the error mark printing function 104 prints an error mark on the roll paper P is after the adjustment patch formed on the roll paper P that caused the adjustment error has passed through the inline scanner 70. In other words, the position of the error mark will be one or several pages away from the position of the adjustment patch formed on the roll paper P that caused the adjustment error. For this reason, it is preferable to add an explanation to the user, for example, on the error history display screen, so that they can recognize in advance the correspondence between the position of the error mark and the position of the adjustment patch formed on the roll paper P that caused the adjustment error.

[0104] The form of the error mark is arbitrary and can be any form, including letters, symbols, or patterns.

[0105] [Operation of the control unit 100] Figure 10 is a flowchart showing an example of the operations performed by the control unit 100 (in this case, the functions of the error operation determination function 102, the error history display function 103, and the error mark printing function 104) when an adjustment error is detected.

[0106] The flowchart in Figure 10 shows the actions that the control unit 100 performs on each page during print job execution to detect abnormalities in the real-time adjustment function. Specifically, for each page, the control unit 100 acquires image information of the adjustment patch on the roll paper P where the object to be inspected is located from the inline scanner 70, performs adjustment control using the real-time adjustment function 101, and then executes the flowchart in Figure 10.

[0107] First, in step S1, the control unit 100 determines whether or not a real-time adjustment error has occurred. If no adjustment error is detected (step S1: NO), the control unit 100 terminates the process shown in the flowchart of Figure 10. On the other hand, if an adjustment error is detected (step S1: YES), the control unit 100 proceeds to step S2 and starts processing to determine the operating state of the image forming apparatus U.

[0108] In step S2, the control unit 100 adds information about the adjustment error to the memory unit (for example, RAM 100c) that stores the error history.

[0109] In step S3, the control unit 100 instructs the image forming unit 40 to print an error mark when forming the image on the next page.

[0110] In step S4, the control unit 100 confirms the setting for the behavior when an adjustment error is detected. Here, it is assumed that the user has set the behavior when an adjustment error is detected in advance before printing starts. Such behavior setting information is stored in a storage unit (for example, RAM 100c), and in steps S4 and S5, the control unit 100 reads such behavior setting information from the storage unit.

[0111] In step S4, for example, the control unit 100 checks whether the behavior setting when an adjustment error is detected is set to "always stop", "never stop", or "automatic stop". If it is set to "always stop", the control unit 100 proceeds to step S11; if it is set to "never stop", it proceeds to step S12; and if it is set to "automatic stop", it proceeds to step S5.

[0112] In step S5, the control unit 100 reads the settings for "enabled" and "disabled" for each of the first to fourth determination modes in "automatic stop" from the storage unit (for example, RAM 100c), and in steps S6 to S10, it performs an operation determination in accordance with the determination criteria for the determination mode for which "enabled" is set.

[0113] Specifically, in step S6, the control unit 100 determines whether the image formation distance to error detection in the currently executing print job is greater than or equal to a first threshold. If the image formation distance is greater than or equal to the first threshold (step S6: YES), the process proceeds to step S11. If the image formation distance is less than the first threshold (step S6: NO), the process proceeds to step S12.

[0114] Furthermore, in step S7, the control unit 100 determines whether the image formation distance to error detection in the currently executing print job is greater than or equal to the first threshold. If the image formation distance is greater than or equal to the first threshold (step S7: YES), the process proceeds to step S11. If the image formation distance is less than the first threshold (step S7: NO), the process proceeds to step S12. (Step S7 is applied when the setting is configured to apply the first determination mode even when printing is resumed.)

[0115] Furthermore, in step S8, the control unit 100 determines whether the load on the paper discharge roller is less than the second threshold. If the load is less than the second threshold (step S8: YES), the process proceeds to step S11. If the load is equal to or greater than the second threshold (step S8: NO), the process proceeds to step S12.

[0116] Furthermore, in step S9, the control unit 100 determines whether the remaining amount of paper on the paper feed roller is equal to or greater than the third threshold. If the remaining amount is equal to or greater than the third threshold (step S9: YES), the process proceeds to step S11. If the remaining amount is less than the third threshold (step S9: NO), the process proceeds to step S12.

[0117] Furthermore, in step S10, the control unit 100 determines whether the number of error detections is equal to or greater than the fourth threshold. If the number of error detections is equal to or greater than the fourth threshold (step S10: YES), the process proceeds to step S11. If the number of error detections is less than the fourth threshold (step S10: NO), the process proceeds to step S12.

[0118] In step S11, the control unit 100 stops the currently running print job.

[0119] In step S12, the control unit 100 makes a decision to continue the currently running print job and stores the history of that decision as an error history.

[0120] In step S13, the control unit 100 changes the automatic execution of the next job to OFF.

[0121] The control unit 100 performs the above-described determination process to determine the operation of the image forming apparatus U (i.e., whether to stop printing or continue printing) when an adjustment error is detected in the real-time adjustment function 101. This makes it possible to decide whether to stop or continue the currently running print based on the circumstances of the detected adjustment error, especially when the user has set the behavior setting for when an adjustment error is detected to "automatic stop".

[0122] In addition, the flowchart in Figure 10 describes the process in a configuration where, as a setting for "automatic stop," only one of the first to fourth judgment modes is set to "enabled," and the other judgment modes are set to "disabled." However, from a fail-safe perspective, the control unit 100 (error operation judgment function 102) may be configured to allow multiple of the first to fourth judgment modes to be set to "enabled" as a setting for "automatic stop," and to perform judgments on all applicable judgment modes. If any one of the judgment results indicates that there is a possibility of a significant impact on the printed image, the print job may be stopped.

[0123] [effect] As described above, the image forming apparatus U according to this embodiment is An image forming unit having an image carrier that holds toner, and printing an image formed by exposure and development processing on the image carrier onto roll paper, An image reading unit that reads the image formed on the roll paper, The system includes a control unit that controls the image forming unit based on a print job that has received an execution command, The control unit, A real-time adjustment function that, while the print job is being executed, prints an adjustment image onto the roll paper, obtains the reading result of the adjustment image from the image reading unit, and adjusts the image forming conditions in the image forming unit in real time based on the reading result, The system includes an error-response operation determination function that, when an adjustment error indicating a failure in the adjustment is detected in the real-time adjustment function, determines whether to stop or continue the print job based on the circumstances of the adjustment error.

[0124] According to the image forming apparatus U of this embodiment, it is possible to minimize the frequency of temporarily suspending the printing operation of the image forming apparatus U, and to suppress the frequency of blank areas being inserted into the printed image of the product roll paper.

[0125] In particular, the image forming apparatus U according to this embodiment has multiple determination modes for deciding whether to stop or continue printing that is currently in progress, taking into account various ways in which the user uses the image forming apparatus U, and each of the multiple determination modes is configured to allow the user to change which one to apply. This makes it possible for the user to select a determination mode that takes into account how the image forming apparatus U is used. In other words, this makes it possible to suppress unnecessary stopping of the operation of the image forming apparatus U.

[0126] Although specific examples of the present invention have been described in detail above, these are merely illustrative and do not limit the scope of the claims. The technologies described in the claims include various modifications and changes to the specific examples illustrated above. [Industrial applicability]

[0127] According to the image forming apparatus of the present invention, it is possible to minimize the frequency of print job stoppages and reduce the amount of blank space generated in the printed roll paper. [Explanation of Symbols]

[0128] U Image forming apparatus 1. Image forming apparatus main unit 2 Paper feed unit 3. Winding Unit 10 Image reading unit 20 Operation display section 30 Image Processing Unit 40 Image forming unit 411 Exposure equipment 412 Developing equipment 413 Photosensitive drum 414 Charging device 415 Cleaning device 416 Toner Refill Unit 421 Intermediate transfer belt 422 Primary Transfer Roller 423 Support roller 424 Secondary Transfer Roller 425 Belt cleaning device 50 Paper transport section 60 Fixing section 70 In-line scanner (image reading unit) 81 Communications Department 82 Memory section 100 Control Unit 101 Real-time adjustment function 102 Error Operation Determination Function 103 Error history display function 104 Error Mark Printing Function

Claims

1. A roll-to-roll image forming apparatus, An image forming unit having an image carrier that holds toner, and printing an image formed by exposure and development processing on the image carrier onto roll paper, An image reading unit that reads the image formed on the roll paper, The system includes a control unit that controls the image forming unit based on a print job that has received an execution command, The control unit, A real-time adjustment function that, while the print job is being executed, prints an adjustment image onto the roll paper, obtains the reading result of the adjustment image from the image reading unit, and adjusts the image forming conditions in the image forming unit in real time based on the reading result, The system includes an error-response operation determination function that, when detecting an adjustment error indicating a failure in the adjustment in the real-time adjustment function, determines whether to stop or continue the print job based on the circumstances of the adjustment error. The error-causing operation determination function stops the print job if it detects an adjustment error when the image formation distance to the roll paper in the print job is less than a first threshold, and continues the print job if it detects an adjustment error when the image formation distance to the roll paper in the print job is equal to or greater than the first threshold. Image forming apparatus.

2. A roll-to-roll image forming apparatus, An image forming unit having an image carrier that holds toner, and printing an image formed by exposure and development processing on the image carrier onto roll paper, An image reading unit that reads the image formed on the roll paper, The system includes a control unit that controls the image forming unit based on a print job that has received an execution command, The control unit, A real-time adjustment function that, while the print job is being executed, prints an adjustment image onto the roll paper, obtains the reading result of the adjustment image from the image reading unit, and adjusts the image forming conditions in the image forming unit in real time based on the reading result, The system includes an error-response operation determination function that, when detecting an adjustment error indicating a failure in the adjustment in the real-time adjustment function, determines whether to stop or continue the print job based on the circumstances of the adjustment error. The error detection function stops the print job if it detects an adjustment error when the amount of roll paper wound around the paper output roller is less than the second threshold, and continues the print job if it detects an adjustment error when the amount of roll paper wound around the paper output roller is equal to or greater than the second threshold. Image forming apparatus.

3. A roll-to-roll image forming apparatus, An image forming unit having an image carrier that holds toner, and printing an image formed by exposure and development processing on the image carrier onto roll paper, An image reading unit that reads the image formed on the roll paper, The system includes a control unit that controls the image forming unit based on a print job that has received an execution command, The control unit, A real-time adjustment function that, while the print job is being executed, prints an adjustment image onto the roll paper, obtains the reading result of the adjustment image from the image reading unit, and adjusts the image forming conditions in the image forming unit in real time based on the reading result, The system includes an error-response operation determination function that, when detecting an adjustment error indicating a failure in the adjustment in the real-time adjustment function, determines whether to stop or continue the print job based on the circumstances of the adjustment error. The error detection function stops the print job if it detects an adjustment error when the remaining amount of roll paper wound around the paper feed roller is equal to or greater than the third threshold, and continues the print job if it detects an adjustment error when the remaining amount of roll paper wound around the paper feed roller is less than the third threshold. Image forming apparatus.

4. The error-causing operation determination function stops the print job if the number of times the adjustment error has been detected since the start of the print job exceeds the fourth threshold, and continues the print job if the number of times the adjustment error has been detected since the start of the print job is less than the fourth threshold. The image forming apparatus according to claim 1.

5. The threshold used by the error handling function to determine whether to stop or continue the print job is user-configurable. The image forming apparatus according to claim 1.

6. A roll-to-roll image forming apparatus, An image forming unit having an image carrier that holds toner, and printing an image formed by exposure and development processing on the image carrier onto roll paper, An image reading unit that reads the image formed on the roll paper, The system includes a control unit that controls the image forming unit based on a print job that has received an execution command, The control unit, A real-time adjustment function that, while the print job is being executed, prints an adjustment image onto the roll paper, obtains the reading result of the adjustment image from the image reading unit, and adjusts the image forming conditions in the image forming unit in real time based on the reading result, The system includes an error-response operation determination function that, when detecting an adjustment error indicating a failure in the adjustment in the real-time adjustment function, determines whether to stop or continue the print job based on the circumstances of the adjustment error. The error operation determination function has multiple determination modes for estimating the impact of the detected cause of the adjustment error on subsequent printing, based on the circumstances of the adjustment error. The error operation determination function is configured to allow the user to switch between enabling and disabling each of the multiple determination modes according to user settings. Image forming apparatus.

7. A roll-to-roll image forming apparatus, An image forming unit having an image carrier that holds toner, and printing an image formed by exposure and development processing on the image carrier onto roll paper, An image reading unit that reads the image formed on the roll paper, The system includes a control unit that controls the image forming unit based on a print job that has received an execution command, The control unit, A real-time adjustment function that, while the print job is being executed, prints an adjustment image onto the roll paper, obtains the reading result of the adjustment image from the image reading unit, and adjusts the image forming conditions in the image forming unit in real time based on the reading result, When an adjustment error indicating a failure in the adjustment is detected in the real-time adjustment function, an error-response operation determination function determines whether to stop or continue the print job based on the circumstances of the adjustment error. The system includes an error history display function that, if the print job continues when an adjustment error is detected based on the error operation determination function, stores the history of the detected adjustment error and displays the history on the display unit. Image forming apparatus.

8. If the aforementioned adjustment error is detected, the system further has an error mark printing function that prints a predetermined mark on the roll paper to indicate the location within the roll paper that caused the adjustment error. The image forming apparatus according to claim 1.

9. A roll-to-roll image forming apparatus, An image forming unit having an image carrier that holds toner, and printing an image formed by exposure and development processing on the image carrier onto roll paper, An image reading unit that reads the image formed on the roll paper, The system includes a control unit that controls the image forming unit based on a print job that has received an execution command, The control unit, A real-time adjustment function that, while the print job is being executed, prints an adjustment image onto the roll paper, obtains the reading result of the adjustment image from the image reading unit, and adjusts the image forming conditions in the image forming unit in real time based on the reading result, The system includes an error-response operation determination function that, when detecting an adjustment error indicating a failure in the adjustment in the real-time adjustment function, determines whether to stop or continue the print job based on the circumstances of the adjustment error. The error operation determination function, when it detects an adjustment error and allows the print job to continue, will temporarily suspend the operation of the device when the print job is completed, without executing the next print job scheduled to follow the previous print job. Image forming apparatus.

10. The error handling function waits for a job continuation command from the user and then starts executing the next print job. The image forming apparatus according to claim 9.

11. A roll-to-roll image forming apparatus, An image forming unit having an image carrier that holds toner, and printing an image formed by exposure and development processing on the image carrier onto roll paper, An image reading unit that reads the image formed on the roll paper, The system includes a control unit that controls the image forming unit based on a print job that has received an execution command, The control unit, A real-time adjustment function that, while the print job is being executed, prints an adjustment image onto the roll paper, obtains the reading result of the adjustment image from the image reading unit, and adjusts the image forming conditions in the image forming unit in real time based on the reading result, When an adjustment error indicating a failure in the adjustment is detected in the real-time adjustment function, an error-response operation determination function determines whether to stop or continue the print job based on the circumstances of the adjustment error. The system includes an error notification function that, when a printed roll of paper is replaced, notifies the user if the adjustment error was detected during printing on that roll of paper. Image forming apparatus.

12. A control method for a roll-to-roll type image forming apparatus, While a print job is running, an adjustment image is printed on roll paper, and the reading result of the adjustment image is obtained from the image reading unit. Based on the reading result, the image forming conditions in the image forming unit are adjusted in real time. If an adjustment error indicating a failure in the adjustment is detected, a decision is made to stop or continue the print job based on the circumstances of the adjustment error. If the adjustment error is detected when the image formation distance to the roll paper in the print job is less than the first threshold, the print job is stopped. If the adjustment error is detected when the image formation distance to the roll paper in the print job is equal to or greater than the first threshold, the print job is continued. Control method.

13. A control program for a roll-to-roll type image forming apparatus, While a print job is running, an adjustment image is printed on roll paper, and the reading result of the adjustment image is obtained from the image reading unit. Based on the reading result, the image forming conditions in the image forming unit are adjusted in real time. If an adjustment error indicating a failure in the adjustment is detected, a decision is made to stop or continue the print job based on the circumstances of the adjustment error. If the adjustment error is detected when the image formation distance to the roll paper in the print job is less than the first threshold, the print job is stopped. If the adjustment error is detected when the image formation distance to the roll paper in the print job is equal to or greater than the first threshold, the print job is continued. Control program.

Images