Image forming device, image forming system, feed device, method for detecting positional deviation of recording medium, and program for detecting positional deviation

Abstract

To detect a positional deviation of a regulation member in a main scan direction.SOLUTION: An image forming system 1 comprises a sheet storage unit 106 that stores a recording medium, a regulation member 105 that regulates the position of the recording medium stored in the sheet storage unit 106, and a detecting unit 107 that detects a skew or main scan-directional shift of the recording medium fed onto a feed pathway from the sheet storage unit 106.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an image forming apparatus, an image forming system, a conveying apparatus, a method for detecting misalignment of a recording medium, and a misalignment detection program.

Background Art

[0002] An image forming apparatus such as an electrophotographic apparatus is provided with a storage unit for stacking and storing recording media (such as paper). The image forming apparatus feeds the recording medium from the storage unit to the image forming unit (printer engine), and forms an image on the recording medium in the image forming unit. Further, the storage unit is provided with a regulating member for regulating the position of the recording medium. The regulating member aligns the positions of the recording medium in the main scanning direction and the sub-scanning direction in the storage unit. Thereby, the image forming apparatus makes the position of image formation in the image forming unit appropriate.

[0003] Here, when there is an abnormality in the regulating member, the recording medium may be supplied to the image forming unit in a shifted state. In this case, due to the misalignment (discrepancy) between the toner image formed on the photosensitive drum and the recording medium, the toner image may protrude from the recording medium when the image forming apparatus forms an image.

[0004] Since the image forming apparatus forms an image on the protruding portion of the recording medium, drum contamination occurs at the misaligned portion of the recording medium. Further, since the printing position of the recording medium is shifted, it becomes a waste as a defective product.

[0005] On the other hand, if a notch is made in the recording medium, the user can visually detect the shift of the image on the recording medium. Further, if an automatic inspection device is used, the image forming apparatus can detect the misalignment of the recording medium by the automatic inspection device.

[0006] However, these means are means for detecting an abnormality after image formation. Therefore, conventionally, it has not been possible to detect the misalignment of the recording medium before the defective printed matter is formed.

[0007] Here, Patent Document 1 proposes an image forming apparatus that can estimate the position of a regulating plate based on the conveyance status of a recording material. In the abstract of Patent Document 1, it is described that "The image forming apparatus includes a housing means having a regulating plate that houses the recording material and regulates the rear end of the recording material in the paper feeding direction, a paper feeding means that feeds the recording material from the housing means, a detecting means that detects the recording material fed by the paper feeding means, and a measuring means that measures the time from a predetermined timing until the detecting means detects the recording material. The information processing apparatus includes a receiving means that receives the time data measured by the measuring means from the image forming apparatus, a classifying means that classifies the plurality of time data received by the receiving means into a first group and a second group according to the length of time, and a determining means that determines whether the position of the regulating plate is deviated from a reference position corresponding to the size of the recording material housed in the housing means using the time data included in the first group and the time data included in the second group."

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0009] The technology of Patent Document 1 measures the time from a predetermined timing until a detecting means detects a recording material (recording medium). When the time to detect this recording material is delayed, the image forming apparatus of Patent Document 1 determines that there is a problem with the position of the regulating plate (regulating member), and thus the recording material is misaligned.

[0010] However, in the technology of Patent Document 1, the conveyance time between two points of the conveyed recording medium is measured to calculate the paper feeding time, and the position of the rear end of the regulating member is estimated from the paper feeding time. Therefore, in the image forming apparatus described in Patent Document 1, it is impossible to detect a positional deviation in the main scanning direction such as skewing of the recording medium or a shift in the main scanning direction.

[0011] Therefore, in the technology of Patent Document 1, when a positional shift in paper conveyance occurs or when there are many cases of non-conformance due to paper feeding shift during inspection, a skilled service technician checks for defective settings such as a regulating plate in the paper storage section based on his or her experience.

[0012] As described above, in the technology of Patent Document 1, since it is impossible to detect a positional deviation in the main scanning direction such as skewing of the recording medium or a shift in the main scanning direction, it was impossible to detect a positional deviation of the regulating member in the main scanning direction.

[0013] Therefore, an object of the present invention is to provide an image forming apparatus, an image forming system, a conveyance apparatus, a method for detecting a positional deviation of a recording medium, and a positional deviation detection program capable of detecting a positional deviation of a regulating member in the main scanning direction.

Means for Solving the Problems

[0014] (1) A storage section for storing a recording medium, A regulating member for regulating the position of the recording medium stored in the storage section, A detection section for detecting skewing or a shift in the main scanning direction of the recording medium conveyed from the storage section to a conveyance path, An image forming apparatus comprising the same. (2) The image forming apparatus according to (1), further comprising a determination section for determining whether the regulating member is normal based on the skewing or the shift in the main scanning direction of the recording medium detected by the detection section. The image forming apparatus according to (1). (3) The regulating member includes at least a component for regulating the sub-scanning direction of the recording medium, The image forming apparatus according to (1). (4) When the detection unit detects a skew or a shift in the main scanning direction of the recording medium, a notification unit that notifies the user that there is a defect in the component, The image forming apparatus according to (2), further comprising. (5) The notification unit, When the detection unit detects a skew or a shift in the main scanning direction of a plurality of the recording media continuously, notifies the user, The image forming apparatus according to (4). (6) The fact that the regulating member is normal includes that the regulating member itself is normal and the mounting state of the regulating member is normal, The image forming apparatus according to (2). (7) The detection unit, Further detects the amount of shift in the main scanning direction of the conveyed recording medium, The image forming apparatus according to (1). (8) Further comprising an image forming unit that forms an image on the recording medium conveyed from the storage unit, The detection unit, Is provided in the conveyance path from the storage unit to the image forming unit, The image forming apparatus according to (1). (9) Further comprising a paper discharge unit that discharges the recording medium determined by the determination unit that the regulating member is not normal, The image forming apparatus according to (2). (10) A storage unit for storing a recording medium, A regulating member for regulating the position of the recording medium stored in the storage unit, A detection unit for detecting a skew or a shift in the main scanning direction of the recording medium conveyed from the storage unit to the conveyance path, An image forming system comprising. (11) A storage unit for storing a recording medium, A regulating member for regulating the position of the recording medium stored in the storage unit, A detection unit for detecting a skew or a shift in the main scanning direction of the recording medium conveyed from the storage unit to the conveyance path, A conveyance device comprising. (12) A storage unit for storing a recording medium, a regulating member for regulating the position of the recording medium stored in the storage unit, a detecting unit for detecting a skew or a shift in the main scanning direction of the recording medium conveyed from the storage unit to a conveyance path, wherein the detecting unit executes a step of detecting a skew or a shift in the main scanning direction of the recording medium. (13) A storage unit for storing a recording medium, a regulating member for regulating the position of the recording medium stored in the storage unit, a detecting unit for detecting a skew or a shift in the main scanning direction of the recording medium conveyed from the storage unit to a conveyance path, a procedure for determining whether the regulating member is normal based on the skew or the shift in the main scanning direction of the recording medium detected by the detecting unit, a position shift detection program for causing the procedure to be executed. [Advantages of the Invention]

[0015] According to the present invention, it is possible to detect a positional shift of the regulating member in the main scanning direction. [Brief Description of the Drawings]

[0016]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Embodiments for Carrying Out the Invention

[0017] Hereinafter, embodiments for carrying out the present invention will be described in detail. Note that the embodiments described below are examples for realizing the present invention, and should be appropriately modified or changed according to the configuration of the apparatus to which the present invention is applied and various conditions. The present invention is not limited to the following embodiments. Also, in each figure, the same components are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

[0018] FIG. 1 is an explanatory diagram showing a schematic system configuration of an image forming system 1 according to the present embodiment. The image forming system 1 is a system that forms an image on a recording medium. The recording medium is composed of, for example, paper. Note that the recording medium is not limited to paper. For example, the recording medium may be a standard long sheet or a sheet such as an OHP (OverHead Projector) sheet. Further, the image forming system 1 can use an inkjet method or the like in addition to the electrophotographic method as an image forming method.

[0019] As shown in FIG. 1, the image forming system 1 according to the present embodiment includes a paper storage unit 106, a detection unit 107, an image forming unit 104, paper discharge units 109 and 110, and a conveyance path 116.

[0020] In FIG. 1, the paper discharge unit 109 is provided downstream of the image forming unit 104. The paper discharge unit 110 is provided downstream of the detection unit 107, but is not limited thereto, and the paper discharge unit 110 may not be provided. If only the paper discharge unit 109 exists downstream of the image forming unit 104 and the paper discharge unit 110 is not provided, and if a paper conveyance failure or the like is detected, it is preferable to pass the paper through without forming an image thereon. Further, in order to distinguish from genuine products, when discharging to a finisher downstream of the image forming unit 104 by offset paper discharge, it is preferable to discharge to a tray different from the genuine products.

[0021] The paper storage unit 106 stores a recording medium. The paper storage unit 106 stores sheets of paper as recording media in a stacked manner, and feeds out the stored recording media toward the image forming unit 104. In this case, the paper storage unit 106 sends the recording medium to the conveyance path 116.

[0022] The conveyance path 116 is a path for conveying a recording medium from the paper storage unit 106 to the paper discharge unit 109. The conveyance path 116 includes a plurality of rollers (not shown), a paper feed conveyance path (not shown) and a conveyance path (not shown), and a reverse conveyance path (not shown) for forming an image on both sides of the recording medium.

[0023] The detection unit 107 detects skewing or a shift in the main scanning direction of the recording medium conveyed from the paper storage unit 106 to the conveyance path 116. The detection unit 107 is configured to include, for example, a media sensor. The detection unit 107 is provided in the path (i.e., the conveyance path 116) through which the recording medium is conveyed from the paper storage unit 106 to the image forming unit 104. When the detection unit 107 detects skewing or a shift in the main scanning direction of the recording medium, the determination unit 108 determines that the regulating member 105 described later is abnormal, and discharges the recording medium from the paper discharge unit 109.

[0024] As described above, when the detection unit 107 detects skewing or a shift in the main scanning direction of the recording medium, before the image forming unit 104 forms an image on the recording medium, the determination unit 108 discharges the recording medium from the paper discharge unit 109 or the paper discharge unit 110. Further, the detection unit 107 may detect the amount of deviation of the recording medium conveyed from the paper storage unit 106 in the main scanning direction.

[0025] The image forming unit 104 forms an image on the recording medium conveyed from the paper storage unit 106. That is, the image forming unit 104 forms an image based on image data on the recording medium using a well-known image forming process such as an electrophotographic process including the steps of charging, exposing, developing, transferring, and fixing. The image forming unit 104 conveys the recording medium on which the image is formed to the paper discharge unit 109 installed on the downstream side via the conveyance path 116.

[0026] The paper discharge units 109 and 110 discharge the recording medium. The paper discharge unit 109 discharges the recording medium from the paper discharge trays 151 and 152 (see FIG. 2) of the paper discharge device 15. The paper discharge unit 110 discharges the recording medium from the paper discharge tray 153 (see FIG. 2).

[0027] For example, in the paper output tray 152, the recording medium determined that the regulating member 105 is normal is discharged. On the other hand, in the paper output tray 153, the recording medium determined that the regulating member 105 is not normal is discharged. On the other hand, in the paper output tray 151, both the recording member determined that the regulating member 105 is normal and the recording member determined that the regulating member 105 is not normal are discharged. Note that the recording medium determined that the regulating member 105 is not normal may be discharged to the paper output tray 152.

[0028] Regarding the offset paper discharge for discharging the normal recording medium and the abnormal recording member by the paper output tray 151, it will be described later with reference to FIG. 4. Note that the paper discharge units 109 and 110 only need to be able to discharge at least the recording medium determined that the regulating member 105 is not normal, and only need to have at least one of the paper output tray 151 and the paper output tray 153.

[0029] FIG. 2 is an explanatory diagram showing a specific configuration of the image forming system 1 according to the present embodiment. As shown in FIG. 2, the image forming system 1 according to the present embodiment includes a paper feeding unit 12, an image forming apparatus 13, and a paper discharging apparatus 15. The paper feeding unit 12, the image forming apparatus 13, and the paper discharging apparatus 15 are sequentially connected from the upstream side to the downstream side of the conveyance path 116 when conveying the recording medium.

[0030] The paper feeding unit 12 shown in FIG. 2 constitutes the paper storage unit 106 of FIG. 1. The paper feeding unit 12 includes, for example, a plurality of large-capacity paper feeding stages 121 to 123. These large-capacity paper feeding stages 121 to 123 store the recording media used for image formation. The paper feeding unit 12 sends out the recording media stored in these large-capacity paper feeding stages 121 to 123 to the image forming apparatus 13 one by one.

[0031] The image forming apparatus 13 shown in FIG. 2 includes the image forming unit 104, the detection unit 107, and the paper discharging unit 110 of FIG. 1. The paper discharging unit 110 includes a paper output tray 153.

[0032] The paper discharge device 15 shown in Fig. 2 constitutes the paper discharge unit 109 of Fig. 1. The paper discharge device 15 is configured to include paper discharge trays 151 and 152.

[0033] Fig. 3 is a block diagram of the image forming system 1 according to the present embodiment. As shown in Fig. 3, the image forming system 1 is configured to include a CPU (Central Processing Unit) 100, a ROM (Read Only Memory) 101, a RAM (Random Access Memory) 102, and a non-volatile memory 103. Further, the image forming system 1 is configured to include an image forming unit 104 and a network connection unit 112.

[0034] Moreover, the image forming system 1 is configured to include a regulating member 105, a paper storage unit 106, a detection unit 107, a determination unit 108, paper discharge units 109 and 110, a notification unit 113, a paper feed sensor 115, a conveyance path 116, and paper discharge trays 151 to 153.

[0035] The CPU 100 performs various arithmetic processes, for example, by executing programs stored in the ROM 101. The ROM 101 is a non-volatile memory and stores various programs and various data for controlling the image forming system 1. The RAM 102 is a volatile memory and temporarily stores programs and data as a working area for the CPU 100.

[0036] The non-volatile memory 103 is a large-capacity storage device such as a hard disk and stores various programs and various data. The CPU 100 is a computer that executes each process by executing programs stored in the ROM 101 or the non-volatile memory 103.

[0037] Here, when the CPU 100 executes a program (for example, a positional deviation detection program) stored in the ROM 101, in this embodiment, for example, the determination unit 108, the paper discharge unit 109, and the notification unit 113 are embodied. In this embodiment, not limited thereto, the determination unit 108, the paper discharge unit 109, and the notification unit 113 may be realized by hardware.

[0038] The regulating member 105 regulates the position of the recording medium stored in the paper storage unit 106. The regulating member 105 is configured to include a member that regulates at least the position of the recording medium in the main scanning direction and the position in the sub-scanning direction.

[0039] The determination unit 108 determines whether the regulating member 105 is normal based on the skew or the shift in the main scanning direction of the recording medium detected by the detection unit 107. The determination unit 108 determines, for example, whether the regulating member 105 is normal based on the component itself of the regulating member 105 or the mounting state of the regulating member 105.

[0040] For example, when the component itself of the regulating member 105 is not normal, the determination unit 108 includes, for example, the aging deterioration of the regulating plate constituting the regulating member 105, the loosening of the screw, and the distortion of the pad forming the guide. In addition, when the mounting state of the regulating member 105 is not normal, the determination unit 108 includes, for example, the omission of locking the regulating member 105 and the overloading of the recording medium due to human error when the recording medium is stored in the paper storage unit 106.

[0041] When the determination unit 108 determines that the regulating member 105 is not normal, the notification unit 113 notifies the user to that effect. Here, the notification unit 113 is not limited to sequentially notifying the user when the determination unit 108 determines that the regulating member 105 is not normal. That is, the notification unit 113 may notify the user when the determination unit 108 continuously determines that the regulating member is not normal for a plurality of recording media.

[0042] The paper supply sensor 115 is provided in the paper storage unit 106 and detects the size and paper quality of the stored recording medium. The paper supply sensor 115 detects, for example, that the size of the stored paper is A4 size or A3 size.

[0043] The network connection unit 112 is a network interface for communicating with other devices. The network connection unit 112 connects to an external server, for example.

[0044] FIG. 4 is an explanatory diagram showing an example in which the paper discharge unit 109 controls offset paper discharge and discharges from the paper discharge tray 151 while distinguishing between a normal product and a recording medium (non-normal product) in which an abnormality has been detected.

[0045] As shown in FIG. 4, for example, the paper discharge tray 151 in FIG. 2 distinguishes between the normal recording media 91 and 93 and the non-normal recording media 92 in which an abnormality has been detected under the control of the paper discharge unit 109, and offsets the non-normal recording media 92 in which an abnormality has been detected. Specifically, the paper discharge unit 109 discharges the non-normal recording media 92 in which an abnormality has been detected by shifting them by a predetermined value in a direction perpendicular to the discharge direction with respect to the normal recording media 91 and 93.

[0046] In FIG. 4, the non-normal recording media 92 are offset and discharged in a direction perpendicular to the discharge direction. By offsetting and discharging to the paper discharge tray 151, the paper discharge unit 109 can distinguish and discharge the non-normal recording media 92 from the normal products in a space-saving manner without separately securing a space for discharging the non-normal recording media 92. Note that in FIG. 4, offset paper discharge is performed on the paper discharge tray 151, but offset paper discharge may be performed on the paper discharge tray 153.

[0047] <Detection of Shift in Paper Conveyance Position at Detection Unit> Next, the detection of the shift in the paper conveyance position at the detection unit 107 will be described. First, the paper storage unit 106 stores recording media such as paper. A paper feed sensor 115 is provided in the paper storage unit 106. The paper feed sensor 115 detects the size (paper size) of the recording media stored in the paper storage unit 106.

[0048] Next, the detection unit 107 calculates the center position in the main scanning direction from the size of the recording media detected by the paper feed sensor 115. For example, when the recording media stored in the paper storage unit 106 is A4-sized paper, the short side in the main scanning direction is 210 [mm]. Therefore, the center position of the short side of the A4 size is 105 [mm]. Incidentally, the size of the recording media may be obtained based on the paper profile information or the like input by the user at the time of setting the print job. Thereby, the detection unit 107 calculates the center position in the main scanning direction when receiving a print job, for example, in the flowchart of FIG. 5 described later, or obtains the center position in the main scanning direction based on the information set by the user in the print job.

[0049] Thereby, the detection unit 107 monitors whether the center position of the recording media coincides with the center position of the detection unit 107 until the recording media is conveyed from the paper storage unit 106 to the detection unit 107 and then to the image forming unit 104 (image forming apparatus 13). By continuously monitoring whether the center position of the recording media coincides with the center position of the detection unit 107, the detection unit 107 monitors the shift of the paper conveyance position, and when the center position and the center position are deviated, detects the shift amount.

[0050] Further, the detection unit 107 may store the detected shift amount in the non-volatile memory 103. Based on the stored shift amount (or the detected shift amount), the detection unit 107 can also identify the regulating member 105 that has a great influence on the conveyance of the recording medium. For example, among the regulating members 105, when the shift amounts of the detected guide plates 1051 and 1052 (described later) are larger than the shift amount of the guide plate 1053 (described later) stored in the non-volatile memory 103, it is determined that the guide plates 1051 and 1052 have a greater influence on the conveyance of the recording medium than the guide plate 1053. Note that the guide plates 1051 and 1052 are members that regulate the main scanning direction, which will be described later. Also, the guide plate 1053 is a member that regulates the sub-scanning direction, which will be described later. Further, the shift amount in the sub-scanning direction can be obtained by an existing known technique (for example, Patent Document 1).

[0051] <First Embodiment> FIG. 5 is a flowchart showing a process in which the image forming system 1 according to the first embodiment detects misalignment of a recording medium in the main scanning direction before executing a print job. In order to explain the misalignment of the recording medium in the main scanning direction, description will be made using explanatory diagrams showing the state of conveyance of the recording medium in FIGS. 6 to 10.

[0052] First, the image forming system 1 receives a print job (step S01). When the image forming system 1 receives a print job, it feeds out sheets of paper 9, which are recording media, one by one from the paper storage unit 106 toward the image forming unit 104.

[0053] FIG. 6 is an explanatory diagram showing a state in which the paper storage unit 106 starts to convey the paper 9 toward the image forming unit 104.

[0054] As shown in FIG. 6, the paper storage unit 106 includes guide plates 1051 to 1053, which are regulating members. The regulating member 105 is composed of three guide plates 1051 to 1053. The guide plates 1051 and 1052 are members that regulate the position of the paper 9 in the main scanning direction from the center position 20 of the conveyance path 116.

[0055] The guide plates 1051 and 1052 regulate the position of the sheet 9 in the main scanning direction by sandwiching the short side of the sheet 9. The guide plates 1051 and 1052 have the role of guiding the center position 21 of the sheet 9 to the center position 20 of the conveyance path 116 in the sheet storage unit 106. Further, the guide plate 1053 is a member that regulates the position of the sheet 9 in the sub-scanning direction. The guide plate 1053 has the role of a stopper that holds one side of the sheet 9 in the sheet storage unit 106.

[0056] Returning to FIG. 5, the description will be continued. The image forming system 1 feeds out the sheet 9 from the sheet storage unit 106 toward the image forming unit 104 (conveyance direction 200). The detection unit 107 reads the conveyed sheet 9 (step S03). When the sheet 9 approaches the detection unit 107, the determination unit 108 determines whether there is a positional deviation of the sheet 9 in the main scanning direction (step S05).

[0057] Specifically, the detection unit 107 detects the skew or the shift in the main scanning direction of the sheet 9 conveyed from the sheet storage unit 106 to the conveyance path 116. The determination unit 108 determines whether there is a positional deviation of the center position 21 of the sheet 9 based on the skew or the shift in the main scanning direction of the sheet 9 detected by the detection unit 107, and determines whether the guide plates 1051 and 1052 constituting the regulating member 105 are normal.

[0058] In step S05, when there is no positional deviation in the main scanning direction at the center position 21 of the sheet 9 (No in step S05), the determination unit 108 determines that the guide plates 1051 and 1052 are normal. In this case, the image forming unit 104 forms an image on this sheet 9 (step S07). Then, the image forming system 1 determines whether printing for the number of sheets determined in the print job has been completed (step S08). If printing for the number of sheets determined in the print job has not been completed (No in step S08), the process returns to step S03. On the other hand, if printing for the number of sheets determined in the print job has been completed (Yes in step S08), the process in FIG. 5 ends.

[0059] On the other hand, when there is a positional deviation in the main scanning direction at the center position 21 of the sheet 9 (Yes in step S05), the determination unit 108 determines that the guide plates 1051 and 1052 are not normal. In this case, since there is a positional deviation in the main scanning direction at the center position 21 of the sheet 9, the notification unit 113 notifies the user that the guide plates 1051 and 1052 constituting the restricting member 105 are abnormal (step S09).

[0060] FIG. 7 and FIG. 8 are explanatory diagrams showing a state during conveyance in which the determination unit 108 determines that there is no positional deviation in the main scanning direction at the center position 21 of the sheet 9.

[0061] As shown in FIG. 7, the detection unit 107 has a media sensor 1071. The media sensor 1071 is provided on the sheet storage unit 106 side of the detection unit 107. The media sensor 1071 detects the center position 21 in the sheet conveyance direction (conveyance direction 200) of the sheet 9. Note that the media sensor 1071 may detect the entire sheet 9, or may detect only the center position 21 which is a part of the sheet 9.

[0062] The media sensor 1071 is not limited to the illustrated size. For example, when the media sensor 1071 detects the entire sheet 9, it is provided so as to cover the entire sheet 9, and detects the entire sheet as the sheet 9 is conveyed. Further, when the media sensor 1071 detects only the center position 21 which is a part of the sheet 9, it is provided in a size for detecting the center position 21, and detects the center position 21 of the sheet 9 as the sheet 9 is conveyed.

[0063] Also, as described above, for example, the paper feed sensor 115 provided in the paper storage unit 106 detects the size of the sheet 9 stored in the paper storage unit 106 in advance, and detects the sizes in the main scanning direction and the sub-scanning direction of the sheet 9. The media sensor 1071 in the paper discharge unit 109 detects the center position 21 on the leading edge side of the conveyed sheet 9, and the determination unit 108 determines whether or not the center position 21 on the leading edge side is along the center position 20 of the conveyance path 116.

[0064] Also, as shown in FIG. 8, the media sensor 1071 detects that the center position 22 on the rear end side of the sheet 9 passes. In this case, the media sensor 1071 detects that the center position 22 on the rear end side of the conveyed sheet 9 is along the center position 20 of the conveyance path 116.

[0065] As shown in FIGS. 7 and 8, when the center positions 21 and 22 in the sheet conveyance direction (scanning direction) of the sheet 9 are along the center position 20 of the conveyance path 116, the determination unit 108 determines that there is no positional deviation of the sheet 9 in the main scanning direction.

[0066] FIGS. 9 and 10 are explanatory diagrams showing a state during conveyance in which the determination unit 108 determines that there is a positional deviation in the main scanning direction of the sheet 9.

[0067] As shown in FIG. 9, the media sensor 1071 of the detection unit 107 detects that the center position 21 in the sheet conveyance direction (conveyance direction 200) of the sheet 9 is not along the center position 20 of the conveyance path 116. As described above, for example, the media sensor 1071 calculates the center position 21 on the leading end side of the sheet 9 conveyed from the sheet storage unit 106, and detects that the center position 21 on the leading end side is not along the center position 20 of the conveyance path 116.

[0068] Also, as shown in FIG. 10, the media sensor 1071 detects that the center position 22 of the rear end of the sheet 9 passes. In this case, the media sensor 1071 detects that the center position 22 in the main scanning direction of the rear end of the conveyed sheet 9 is not along the center position 20 of the conveyance path 116.

[0069] As shown in FIGS. 9 and 10, when the center positions 21 and 22 in the main scanning direction of the sheet 9 are not along the center position 20 of the conveyance path 116, the determination unit 108 determines that there is a positional deviation of the sheet 9 in the main scanning direction.

[0070] Next, FIG. 11 shows a display screen indicating that when the determination unit 108 determines that the guide plates 1051 and 1052 are abnormal, the notification unit 113 notifies the user to that effect.

[0071] As shown in FIG. 11, the display screen 400 notifies that the regulating member 105 is abnormal. Further, in the comment column 401, a notification indicating that the guide plates 1051 and 1052 are abnormal is described.

[0072] For example, in the comment column 401, it is displayed that "Based on the detection of the paper or the skew or shift in the main scanning direction of the paper, the guide plate has been determined to be abnormal. Please check the parts or mounting state of the regulating member."

[0073] Returning to FIG. 5, the description will be continued. In step S09, after the notification unit 113 notifies the user that the guide plates 1051 and 1052 are abnormal, the paper discharge unit 109 discharges the paper 9 for which the determination unit 108 has determined that the guide plates 1051 and 1052 are abnormal (step S11).

[0074] In this case, the paper discharge unit 109 uses the paper 9 as the recording medium 92 that has been determined to be abnormal and offset discharged on the paper discharge tray 151. Further, the paper discharge unit 109 may discharge the paper 9 as the recording medium 92 determined to be abnormal from, for example, the paper discharge tray 152.

[0075] When the image forming apparatus 13 (image forming unit 104) conveys the paper 9 for which an abnormality has been determined without forming an image thereon and discharges it as the recording medium 92 from the paper discharge tray 152 or the paper discharge tray 151, the image forming system 1 ends the processing of FIG. 5.

[0076] As described above, the image forming system 1 according to the first embodiment includes a paper storage unit 106, a regulating member 105, and a detection unit 107. The detection unit 107 detects the skew or shift in the main scanning direction of the paper 9 (recording medium) conveyed from the paper storage unit 106 to the conveyance path 116.

[0077] According to the first embodiment, the image forming system 1 detects, by the detection unit 107, the positional deviation of the sheet 9 in the main scanning direction, which is the skew or the shift in the main scanning direction of the sheet 9.

[0078] Thereby, the image forming system 1 according to the first embodiment can detect the positional deviation of the regulating member 105 in the main scanning direction. For example, the inspection work for the setting defect of the regulating member 105 in the sheet storage unit 106 can be started by the service technician at an early stage.

[0079] For example, when the positional shift of the sheet conveyance occurs frequently or continuously, or when there are many cases of non - conformity due to the sheet feeding shift during inspection, a highly skilled service technician checks for setting defects such as the regulating member 105 in the sheet storage unit 106 based on his or her experience.

[0080] Specifically, the service technician checks for the setting defect of the regulating member 105, such as the omission of locking of the guide plates 1051 to 1053 constituting the regulating member 105 and the distortion of the guide plates 1051 to 1053. Also, the service technician may suspect and check for problems such as the loosening of the screws fixing the guide plates 1051 to 1053 and the uneven wear of the conveyance rollers.

[0081] The image forming system 1 of the first embodiment can, for example, give a warning such as a setting defect of the regulating member 105 in the sheet storage unit 106 to the user by the notification unit 113. Thereby, the image forming system 1 can cause anyone to start the inspection work for the setting defect of the regulating member 105 in the sheet storage unit 106 at an early stage, regardless of the skill level of the service technician.

[0082] In addition, the image forming system 1 usually includes a detection unit 107. The detection unit 107 is provided in the image forming apparatus 13 (image forming unit 104) of the image forming system 1 in order to detect a shift in the paper conveyance position. Therefore, the image forming system 1 according to the present embodiment can detect a shift in the paper conveyance position by the detection unit 107 having the media sensor 1071 without adding a special mechanism.

[0083] As described above, the image forming system 1 according to the first embodiment can detect the sheet 9 in which a positional shift has occurred in the main scanning direction before the image forming unit 104 forms an image on the sheet 9.

[0084] Thereby, the image forming system 1 according to the first embodiment can prevent unnecessary consumption of toner and the sheet 9 due to non-genuine products. In addition, the image forming system 1 according to the first embodiment can reduce the downtime for cleaning the image forming system 1 (image forming apparatus 13), such as drum contamination of the image forming unit 104, and the man-hours for cleaning by the service technician.

[0085] <Second Embodiment> In the second embodiment, the notification unit 113 of the image forming system 1 notifies the user when the determination unit 108 continuously determines that the regulating member 105 is abnormal for a plurality of recording media.

[0086] FIG. 12 is a flowchart showing a process in which the image forming system 1 according to the second embodiment notifies the user when it continuously determines that the regulating member 105 is abnormal for a plurality of recording media equal to or more than a threshold number of sheets.

[0087] The flowchart of the image forming system 1 according to the second embodiment is different from the flowchart of the image forming system 1 according to the first embodiment in that, in step S21, it is determined whether or not the next sheet 9 is also misaligned.

[0088] First, the image forming system 1 receives a print job (step S21). When the image forming system 1 receives a print job, it feeds out a sheet of paper 9, which is a recording medium, one by one from the paper storage unit 106 toward the image forming unit 104. The detection unit 107 reads the conveyed sheet of paper 9 (step S23).

[0089] When the sheet of paper 9 approaches the detection unit 107, the determination unit 108 determines whether there is any deviation in the position of the sheet of paper 9 in the main scanning direction (step S25).

[0090] In step S25, if there is no deviation in the position of the sheet of paper 9 in the main scanning direction at the center position 21 of the sheet of paper 9 (No in step S25), the determination unit 108 determines that the guide plates 1051 and 1052 are normal. In this case, the variable indicating the number of consecutive misaligned sheets is initialized to 0 (step S27), and an image is formed on this sheet of paper 9 (step S29). Then, the image forming system 1 determines whether printing for the number of sheets determined in the print job has been completed (step S31). If printing for the number of sheets determined in the print job has not been completed (No in step S31), the process returns to step S23. If printing for the number of sheets determined in the print job has been completed (Yes in step S31), the process in FIG. 12 ends.

[0091] On the other hand, in step S25, if there is a deviation in the position of the sheet of paper 9 in the main scanning direction at the center position 21 of the sheet of paper 9 (Yes in step S25), 1 is added to the variable indicating the number of consecutive misaligned sheets (step S33), and this sheet of paper 9 is discharged (step S35).

[0092] In step S37, the determination unit 108 determines whether the number of consecutive misaligned sheets is equal to or greater than a threshold value. In step S37, if the number of consecutive misaligned sheets is less than the threshold value (No in step S37), the process proceeds to step S31. On the other hand, if the number of consecutive misaligned sheets is equal to or greater than the threshold value (Yes in step S37), the notification unit 113 notifies that the regulating member is abnormal (step S39), and the process in FIG. 12 ends.

[0093] That is, only when the determination unit 108 determines that there is a positional deviation in the main scanning direction at the center position 21 of the sheet 9 continuously for the threshold number of sheets among a plurality of sheets 9, the notification unit 113 notifies the user to that effect.

[0094] When the center positions 21, 22 of the conveyed sheet 9 and the center position 20 of the conveyance path 116 do not match (conveyance positional deviation) continuously occur, the notification unit 113 warns the user of a set defect of the sheet 9 in the sheet storage unit 106 and prompts inspection. Depending on the user, some positional deviation may be tolerated, and occasionally, only one sheet 9 may be displaced in the conveyance path 116.

[0095] Therefore, when the determination unit 108 determines that the sheet 9 is abnormal continuously for the threshold number of times with respect to a plurality of sheets 9 (recording media), the notification unit 113 may warn the user to that effect. The threshold value may be any integer of 2 or more and is not limited.

[0096] Furthermore, in the second embodiment, the notification unit 113 may also warn the user to that effect when a positional deviation occurs frequently.

[0097] As described above, in the image forming system 1 according to the second embodiment, when the determination unit 108 determines that the sheet 9 is abnormal continuously for the threshold number of times with respect to a plurality of sheets 9, the notification unit 113 notifies the user to that effect.

[0098] According to the second embodiment, in the image forming system 1, when it is determined that the sheet 9 is abnormal continuously for the threshold number of times, the notification unit 113 notifies the user to that effect. This is because some users may tolerate some positional deviation, and occasionally, only one sheet 9 may be displaced in the conveyance path 116.

[0099] Also, among the sheets 9 stored in the sheet storage unit 106, for example, it is also possible to assume that the misalignment of the sheets 9 stored in the upper layer has a relatively low reliability. For example, when the maximum number of sheets is stored in the sheet storage unit 106, the sheets are stored up to the upper part of the sheet storage unit. In this case, due to an earthquake or a person colliding with the image forming system 1 or the image forming apparatus 13, etc., the sheets 9 stored in the upper layer are more likely to be misaligned compared to the sheets 9 stored in the middle and lower layers of the sheet storage unit 106.

[0100] On the other hand, it is also possible to assume that the misalignment of the sheets 9 stored in the middle and lower layers of the sheet storage unit 106 has a relatively high reliability. This is because the sheets 9 stored in the middle and lower layers of the sheet storage unit 106 are less likely to be misaligned.

[0101] Therefore, when the determination unit 108 continuously determines that a plurality of sheets 9 are abnormal, the notification unit 113 may notify the user to that effect.

[0102] When a position shift in paper conveyance frequently or continuously occurs, or when there are many cases of nonconformance due to paper feed shift during inspection, a highly skilled operator suspects a setting defect such as a regulating plate in the paper feed tray based on their experience and conducts an inspection. Setting defects include, for example, forgetting to lock the regulating plate, distortion of the regulating plate, loosening of screws, and uneven wear of the conveyance rollers. In this embodiment, by issuing a warning about a setting defect of the regulating plate in the paper feed tray to the user and prompting an inspection, anyone, regardless of their skill level, can start the inspection work for setting defects such as the regulating plate in the paper feed tray at an early stage.

[0103] In this embodiment, without the need to add a special mechanism for detecting a shift in the paper conveyance position, the shift in the paper conveyance position can be detected by the detection unit (media sensor) 107 located in the previous stage before being conveyed to the image forming apparatus 13. By purging the sheets with a position shift before image formation, consumption of toner and paper due to defective products can be prevented, and downtime for in-device cleaning such as drum contamination and the user's man-hours can be reduced.

[0104] (Modification example) The present invention is not limited to the above-described embodiments, and can be implemented with modifications without departing from the gist of the present invention. For example, there are the following (a) to (f).

[0105] (a) The regulating member 105 may include members (guide plates 1051 to 1053) that regulate at least the position in the main scanning direction and the position in the sub-scanning direction of the recording medium. (b) The image forming system 1 may include a notification unit 113 that notifies the user to that effect when the determination unit 108 determines that the regulating member 105 is abnormal. When the determination unit 108 continuously determines that the regulating member 105 is abnormal for a plurality of sheets of paper 9, the notification unit 113 may notify the user to that effect. (c) The determination unit 108 may determine whether the regulating member 105 is normal based on the component itself of the regulating member 105 and the mounting state of the regulating member 105. (d) The detection unit 107 may further detect the amount of deviation of the conveyed paper 9 (recording medium) in the main scanning direction. In this case, when the amount of deviation of the paper 9 in the main scanning direction exceeds a predetermined threshold value, the determination unit 108 can determine that it is abnormal. (e) The image forming system 1 may include an image forming unit 104 that forms an image on the paper 9 conveyed from the paper storage unit 106. In this case, it is desirable that the detection unit 107 be provided in a conveyance path 116 that conveys the paper 9 from the paper storage unit 106 to the image forming unit 104. Also, when the image forming system 1 does not include the image forming apparatus 13 (image forming unit 104), it can also be realized as a conveyance device. Further, in the present embodiment, it can also be applied to an image forming apparatus. (f) The image forming system 1 may include a paper discharge unit 109 that discharges the paper 9 determined by the determination unit 108 to be abnormal in 105. As shown in this embodiment, by providing the paper discharge trays 152 and 151, the paper discharge unit 109 can discharge the paper 9 determined to be abnormal in the guide plates 1051 to 1053 that constitute the regulating member 105. Thereby, the paper discharge unit 109 can discharge the paper 9 determined to be abnormal in the regulating member 105 from the paper discharge trays 152 and 151 before image formation by the image forming apparatus 13 (image forming unit 104). Thereby, the image forming system 1 can avoid wasting toner for printing on non-genuine paper 9 and the printing time of non-genuine (non-conforming) products.

Explanation of Signs

[0106] 1 Image forming system 12 Paper feeding unit 13 Image forming apparatus 15 Paper discharge apparatus 104 Image forming unit 105 Regulating member 1051~1053 Guide plates 106 Paper storage unit (storage unit) 107 Detection unit 108 Determination unit 109 Paper discharge unit 112 Network connection unit 113 Notification unit 115 Paper feeding sensor 116 Conveying path 121~123 High-capacity paper feeding stages 151~153 Paper discharge trays 20 Center position 21, 22 Center positions 200 Conveying direction

Claims

1. A storage unit for storing a recording medium; A regulating member for regulating the position of the recording medium stored in the storage unit; A detection unit for detecting an inclination or a shift in the main scanning direction of the recording medium conveyed from the storage unit to a conveyance path; An image forming apparatus comprising the same.

2. The image forming apparatus according to claim 1, further comprising a determination unit for determining whether the regulating member is normal based on an inclination or a shift in the main scanning direction of the recording medium detected by the detection unit.

3. The regulating member includes at least a component for regulating the sub-scanning direction of the recording medium. The image forming apparatus according to claim 1.

4. The image forming apparatus according to claim 2, further comprising a notification unit for notifying a user that there is a defect in the component when the detection unit detects an inclination or a shift in the main scanning direction of the recording medium.

5. The notification unit notifies the user when the detection unit continuously detects an inclination or a shift in the main scanning direction of a plurality of recording media. The image forming apparatus according to claim 4.

6. The fact that the regulating member is normal includes that the regulating member itself is normal and the mounting state of the regulating member is normal. The image forming apparatus according to claim 2.

7. The detection unit further detects a shift amount in the main scanning direction of the conveyed recording medium. The image forming apparatus according to claim 1.

8. The image forming apparatus further comprises an image forming unit for forming an image on the recording medium conveyed from the storage unit. The detection unit is provided in the conveyance path from the storage unit to the image forming unit, the image forming apparatus according to claim 1.

9. further comprising a paper discharge unit that discharges the recording medium determined by the determination unit to be abnormal in the regulating member, the image forming apparatus according to claim 2.

10. a storage unit for storing a recording medium; a regulating member for regulating the position of the recording medium stored in the storage unit; a detection unit for detecting a skew or a shift in the main scanning direction of the recording medium conveyed from the storage unit to the conveyance path; an image forming system comprising:

11. a storage unit for storing a recording medium; a regulating member for regulating the position of the recording medium stored in the storage unit; a detection unit for detecting a skew or a shift in the main scanning direction of the recording medium conveyed from the storage unit to the conveyance path; a conveyance device comprising:

12. a storage unit for storing a recording medium; a regulating member for regulating the position of the recording medium stored in the storage unit; a method for detecting a displacement of a recording medium, comprising a storage unit for storing a recording medium, a regulating member for regulating the position of the recording medium stored in the storage unit, and a detection unit for detecting a skew or a shift in the main scanning direction of the recording medium conveyed from the storage unit to the conveyance path, wherein the detection unit executes a step of detecting a skew or a shift in the main scanning direction of the recording medium.

13. a storage unit for storing a recording medium; a regulating member for regulating the position of the recording medium stored in the storage unit; a computer comprising a detection unit for detecting a skew or a shift in the main scanning direction of the recording medium conveyed from the storage unit to the conveyance path, A procedure for determining whether the regulating member is normal based on the skew of the recording medium or the shift in the main scanning direction detected by the detection unit. A position shift detection program for causing the above to be executed.

Images