Sheet conveying device, image forming device

Abstract

To provide a sheet conveying device and an image forming device that can prevent a posture of a correction unit from being tilted with respect to a sheet conveying direction by a conveying unit.SOLUTION: An image forming device 100 includes a transport unit 4 that transports a sheet SH1, a correction unit 61 that is arranged upstream of the transport unit 4 in a transport direction D11 of the sheet SH1 by the transport unit 4 and has an opposing surface 61A that faces a side end of the sheet SH1 in a first direction that is perpendicular to the transport direction D11, a transport roller 62 that is arranged upstream of the correction unit 61 in the transport direction D11 and transports the sheet SH1 in a second direction toward the opposing surface 61A, and an angle change unit that changes an inclination angle of the opposing surface 61A with respect to the transport direction D11.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a sheet conveying device and an image forming apparatus. [Background technology]

[0002] There is known an image forming apparatus that includes a correction unit that corrects the conveyance posture of a sheet conveyed toward an image forming unit such as an inkjet head. Also, there is known a related art image forming apparatus that can prevent the posture of the correction unit from being tilted with respect to the conveyance direction of the sheet by the conveyance unit by integrally attaching the correction unit to a conveyance unit that conveys the sheet below the inkjet head (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-30412 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the image forming device relating to the above-mentioned related technology, if the correction unit cannot be attached integrally to the conveying unit, it is not possible to prevent the posture of the correction unit from being tilted relative to the conveying direction of the sheet by the conveying unit.

[0005] An object of the present invention is to provide a sheet conveying device and an image forming apparatus that can prevent the posture of a correction unit from being tilted with respect to the sheet conveying direction by a conveying unit. [Means for solving the problem]

[0006] According to one aspect of the present invention, there is provided a sheet conveying device including a first conveying unit, a correction unit, a second conveying unit, and an angle change unit. The first conveying unit conveys a sheet. The correction unit is located upstream of the first conveying unit in a conveying direction of the sheet by the first conveying unit, and has an opposing surface that faces a side end of the sheet on a first direction side perpendicular to the conveying direction. The second conveying unit is located upstream of the correction unit in the conveying direction, and conveys the sheet in a second direction toward the opposing surface. The angle adjustment unit changes the inclination angle of the opposing surface with respect to the conveying direction.

[0007] An image forming apparatus according to another aspect of the present invention includes the sheet conveying device and an image forming section, the image forming section forming an image on the sheet conveyed by the first conveying section. [Effects of the Invention]

[0008] According to the present invention, it is possible to prevent the posture of the correction unit from being tilted with respect to the conveying direction of the sheet by the conveying unit. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a cross-sectional view showing the configuration of an image forming apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is a plan view showing the configuration of the image forming section, the transport unit, and the line sensor in the image forming apparatus according to the embodiment of the present invention. [Figure 3] FIG. 3 is a plan view showing the configuration of the posture correcting unit in the image forming apparatus according to the embodiment of the present invention. [Figure 4] FIG. 4 is a block diagram showing the system configuration of the image forming apparatus according to the embodiment of the present invention. [Figure 5] FIG. 5 is a flowchart showing an example of the tilt angle adjustment process executed in the image forming apparatus according to the embodiment of the present invention. [Figure 6] FIG. 6 is a diagram showing an example of shape data acquired by the image forming apparatus according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. Note that the following embodiment is an example of the present invention, and does not limit the technical scope of the present invention.

[0011] [Configuration of image forming apparatus 100] First, the configuration of an image forming apparatus 100 according to an embodiment of the present invention will be described with reference to Figures 1 to 4. In Figure 1, a sheet transport path R11 is indicated by a two-dot chain line.

[0012] Image forming apparatus 100 is a printer capable of forming an image on sheet SH1 (see FIG. 1) using an inkjet method. The present invention may also be applied to a fax machine, a copier, or a multifunction peripheral capable of forming an image on sheet SH1 using an inkjet method. The present invention may also be applied to an image forming apparatus capable of forming an image on sheet SH1 using a method other than the inkjet method, such as an electrophotographic method.

[0013] 1, image forming apparatus 100 includes a housing 1, a paper feed section 2, an image forming section 3, a transport unit 4, a paper discharge section 5, an attitude correction section 6, and a shape reading section 7. Image forming apparatus 100 also includes an operation display section 8 and a control section 9 shown in FIG. 4. An apparatus including transport unit 4 and attitude correction section 6 is an example of a sheet transport apparatus of the present invention.

[0014] The housing 1 houses each component of the image forming apparatus 100. As shown in FIG. 1, the housing 1 is composed of a first housing 11, a second housing 12, and a third housing 13 that are connected together. As shown in FIG. 1, the first housing 11 houses the paper feed unit 2 and the posture correction unit 6. As shown in FIG. 1, the second housing 12 houses the image forming unit 3, the transport unit 4, and the shape reading unit 7. As shown in FIG. 1, the third housing 13 houses the paper discharge unit 5.

[0015] The paper feed unit 2 supplies sheets SH1 to the second housing 12. As shown in FIG. 1, the paper feed unit 2 includes a paper feed cassette 21, a pickup roller 22, and a paper feed roller 23. The paper feed cassette 21 stores sheets SH1. Inside the housing 1, the sheets SH1 stored in the paper feed cassette 21 of the first housing 11 are transported along a sheet transport path R11 (see FIG. 1) that passes through the first housing 11, the second housing 12, and the third housing 13 to an output tray 53 (see FIG. 1). The pickup roller 22 picks up the top sheet SH1 of the stack of sheets SH1 stored in the paper feed cassette 21 and sends the sheet SH1 to the sheet transport path R11. The paper feed roller 23 transports the sheet SH1 along the sheet transport path R11.

[0016] The image forming section 3 forms an image on the sheet SH1 conveyed by the conveying unit 4. As shown in FIG.

[0017] 2, each of the line heads 31 to 34 is elongated in a width direction D12 perpendicular to a conveying direction D11 of the sheet SH1 by the conveying unit 4. Specifically, each of the line heads 31 to 34 has a length in the width direction D12 corresponding to the width of the largest size sheet SH1 among the sheets SH1 that can be accommodated in the paper feed cassette 21. The line heads 31 to 34 are arranged side by side at equal intervals along the conveying direction D11.

[0018] As shown in FIG. 2, each of the line heads 31 to 34 has a plurality of recording heads 30. Each of the recording heads 30 ejects ink toward the sheet SH1 transported by the transport unit 4. Each of the recording heads 30 provided in the line head 31 ejects black ink. Each of the recording heads 30 provided in the line head 32 ejects cyan ink. Each of the recording heads 30 provided in the line head 33 ejects magenta ink. Each of the recording heads 30 provided in the line head 34 ejects yellow ink.

[0019] Each of the recording heads 30 includes a plurality of nozzles 30A (see FIG. 2) that eject ink. The plurality of nozzles 30A are provided on the surface of the recording head 30 that faces the sheet SH1 that is transported by the transport unit 4.

[0020] Each recording head 30 also includes a pressure chamber (not shown), a piezoelectric element (not shown), and an individual flow path (not shown) corresponding to each nozzle 30A. The pressure chamber communicates with the nozzle 30A and stores ink. The piezoelectric element ejects ink from the nozzle 30A in response to application of a predetermined drive voltage. The individual flow path is an ink flow path provided between the pressure chamber and a common flow path (not shown) shared by the multiple nozzles 30A. A plurality of the individual flow paths corresponding to the multiple nozzles 30A are connected to the common flow path. The common flow path is connected to an ink supply unit (not shown) that supplies ink to each of the pressure chambers.

[0021] 2, the line head 31 includes three recording heads 30 arranged in a staggered pattern along the width direction D12. Similarly to the line head 31, each of the other line heads 32 to 34 also includes three recording heads 30 arranged in a staggered pattern along the width direction D12.

[0022] The head frame 35 supports the line heads 31 to 34. The head frame 35 is supported by the second housing 12. The number of line heads provided in the image forming unit 3 does not have to be four. Also, the number of recording heads 30 provided in each of the line heads 31 to 34 does not have to be three.

[0023] As shown in FIG. 1, the transport unit 4 is disposed below the line heads 31 to 34. The transport unit 4 transports the sheet SH1 while facing the recording head 30. For example, the transport unit 4 transports the sheet SH1 by a predetermined transport distance each time the recording head 30 ejects ink. The transport unit 4 also stops transporting the sheet SH1 while the recording head 30 is ejecting ink. As shown in FIG. 1, the transport unit 4 includes a transport belt 41 on which the sheet SH1 is placed, a first tension roller 42, a second tension roller 43, and a third tension roller 44 that tension the transport belt 41, and a transport frame 45 that supports these rollers. The gap between the transport belt 41 and the recording head 30 is adjusted so that the gap between the surface of the sheet SH1 and the recording head 30 during image formation is a predetermined distance (e.g., 1 mm). The transport unit 4 is an example of a first transport section of the present invention.

[0024] The first tension roller 42 is rotationally driven by a rotational driving force supplied from a motor (not shown). As a result, the conveyor belt 41 rotates in a direction that allows the sheet SH1 to be conveyed in the conveying direction D11 (see FIG. 1). The conveying unit 4 is also provided with a suction unit (not shown) that sucks air through a number of through holes formed in the conveyor belt 41 to attract the sheet SH1 to the conveyor belt 41.

[0025] The paper discharge unit 5 discharges the sheet SH1 after image formation to the outside of the third housing 13. As shown in FIG. 1, the paper discharge unit 5 includes a first paper discharge roller 51, a second paper discharge roller 52, and a paper discharge tray 53. The first paper discharge roller 51 and the second paper discharge roller 52 transport the sheet SH1 after image formation along a sheet transport path R11. The paper discharge tray 53 is provided on the outer surface of the third housing 13. The sheet SH1 after image formation is discharged to the paper discharge tray 53. The third housing 13 is also provided with a drying device (not shown) that dries the sheet SH1 after image formation that is transported along the sheet transport path R11.

[0026] The posture correcting unit 6 corrects the conveying posture of the sheet SH1 being conveyed toward the image forming unit 3. As shown in FIGS. 1 and 3, the posture correcting unit 6 includes a correcting unit 61, a conveying roller 62, and an angle changing unit 63.

[0027] As shown in FIG. 1, the correction unit 61 is provided upstream of the transport unit 4 in the transport direction D11 of the sheet SH1 by the transport unit 4. The correction unit 61 has an opposing surface 61A (see FIGS. 1 and 3) that faces a side end of the sheet SH1 on the side of a first direction D21 (see FIG. 3) that is perpendicular to the transport direction D11. For example, the correction unit 61 is a flat member that is elongated along the transport direction D11. The correction unit 61 is disposed at an end of the sheet transport path R11 in the first direction D21. The correction unit 61 is also disposed so that the opposing surface 61A is parallel to the transport direction D11.

[0028] As shown in FIG. 1, the transport roller 62 is provided upstream of the correcting unit 61 in the transport direction D11. The transport roller 62 transports the sheet SH1 in a second direction D22 (see FIG. 3) toward the opposing surface 61A. Specifically, as shown in FIG. 3, the transport roller 62 is disposed in a position inclined with respect to the transport direction D11. In other words, the transport roller 62 is disposed in a position in which the rotation axis is inclined with respect to the width direction D12. As shown in FIG. 3, the second direction D22 is a direction inclined with respect to the transport direction D11. The transport roller 62 is an example of a second transport unit of the present invention.

[0029] When the sheet SH1 is conveyed in the second direction D22 by the conveyance roller 62, the side edge of the sheet SH1 on the first direction D21 side comes into contact with the opposing surface 61A of the correction unit 61. This corrects the conveyance posture of the sheet SH1.

[0030] Incidentally, there is known an image forming apparatus that includes a registration roller instead of the correction unit 61. Also, there is known, as related art, an image forming apparatus that can prevent the registration roller from being tilted with respect to the conveying direction D11 by integrally attaching the registration roller to the conveying unit 4.

[0031] However, in the image forming apparatus according to the related art described above, if the registration roller cannot be attached integrally to the transport unit 4, it is not possible to prevent the orientation of the registration roller from tilting with respect to the transport direction D11. For example, if the transport unit 4 is arranged in the second housing 12 and the registration roller is arranged in the first housing 11, the registration roller cannot be attached integrally to the transport unit 4.

[0032] In contrast to this, in the image forming apparatus 100 according to the embodiment of the present invention, as will be described below, it is possible to prevent the posture of the correction unit 61 from being tilted with respect to the transport direction D11.

[0033] The angle changer 63 changes the inclination angle of the opposing surface 61A with respect to the conveying direction D11.

[0034] For example, the angle changer 63 is a stepping motor having a drive shaft 63A (see FIG. 3) that is long in a direction perpendicular to the conveyance direction D11 and the width direction D12.

[0035] The correcting unit 61 is attached to the drive shaft 63A so as to be rotatable integrally with the drive shaft 63A. Specifically, as shown in Fig. 3, the correcting unit 61 is attached to the drive shaft 63A so as to extend from the drive shaft 63A in a direction perpendicular to the extension direction of the drive shaft 63A. The correcting unit 61 is also attached to the drive shaft 63A so that the opposing surface 61A intersects with the rotation direction D23 (see Fig. 3) of the drive shaft 63A.

[0036] The shape reading unit 7 reads the shape of the sheet SH1 being transported along the sheet transport path R11.

[0037] As shown in FIG. 4, the shape reading unit 7 includes a line sensor 71 and an AFE (analog front end) circuit 72.

[0038] As shown in FIG. 1, the line sensor 71 is provided on the sheet transport path R11 upstream of the image forming unit 3 in the transport direction D11 and downstream of the posture correction unit 6 in the transport direction D11. The line sensor 71 is provided above the transport belt 41. As shown in FIG. 2, the line sensor 71 is provided elongated along the width direction D12. The line sensor 71 captures an image of the sheet SH1 transported along the sheet transport path R11.

[0039] For example, the line sensor 71 is a CIS (contact image sensor). The line sensor 71 includes multiple imaging elements arranged side by side in the width direction D12 (see FIG. 2). Each imaging element includes a light-emitting unit and a light-receiving unit. The light-emitting unit emits light toward the conveyor belt 41. The light-receiving unit is configured to receive light emitted from the light-emitting unit and reflected by the conveyor belt 41 or the conveyed sheet SH1, and outputs an analog electrical signal corresponding to the amount of received light. The line sensor 71 captures an image of the sheet SH1 conveyed along the sheet conveyance path R11 at a predetermined imaging cycle. Specifically, the line sensor 71 outputs an analog electrical signal corresponding to an image of the image target (sheet SH1 and conveyor belt 41) facing the line sensor 71 at the imaging cycle. The outer peripheral surface of the conveyor belt 41 is colored, such as black, to suppress reflection of light emitted from the light-emitting unit compared to the background color (white) of the sheet SH1.

[0040] The AFE circuit 72 is an electronic circuit that performs predetermined processing on the analog electrical signal output from the line sensor 71. Specifically, the AFE circuit 72 includes a signal conversion unit that converts the analog electrical signal output from the line sensor 71 into a digital electrical signal (image data). The AFE circuit 72 also includes a binarization unit that performs binarization processing on the image data output from the signal conversion unit. The binarization processing is a process of binarizing each pixel included in the image data output from the signal conversion unit into a value that indicates the presence or absence of sheet SH1. The image data binarized by the binarization unit (hereinafter referred to as "line data") is input to the control unit 9.

[0041] The operation display unit 8 is a user interface of the image forming apparatus 100. The operation display unit 8 includes a display unit and an operation unit. The display unit displays various information in response to control instructions from the control unit 9. For example, the display unit is a flat panel display such as a liquid crystal display. The operation unit inputs various information to the control unit 9 in response to user operations. For example, the operation unit includes operation keys and a touch panel.

[0042] The control unit 9 performs overall control of the image forming apparatus 100. As shown in FIG. 4, the control unit 9 includes a CPU 81, a ROM 82, and a RAM 83. The CPU 81 is a processor that executes various types of arithmetic processing. The ROM 82 is a non-volatile storage device that stores in advance information such as control programs for causing the CPU 81 to execute various types of processing. The RAM 83 is a volatile or non-volatile storage device that is used as a temporary storage memory (work area) for the various types of processing executed by the CPU 81. The CPU 81 performs overall control of the image forming apparatus 100 by executing the various control programs that are stored in advance in the ROM 82.

[0043] 4, the control unit 9 includes a reading processing unit 84, an acquisition processing unit 85, and an adjustment processing unit 86. Specifically, the CPU 81 of the control unit 9 executes the control program stored in the ROM 82 to function as the reading processing unit 84, the acquisition processing unit 85, and the adjustment processing unit 86. Note that the reading processing unit 84, the acquisition processing unit 85, and the adjustment processing unit 86 may be realized by electronic circuits.

[0044] The reading processing unit 84 reads the outer shape of the sheet SH1 that has passed through the correction unit 61.

[0045] For example, the reading processing unit 84 uses the line sensor 71 to acquire shape data X10 (see FIG. 6) that indicates the shape of the sheet SH1 that has passed through the correction unit 61.

[0046] For example, when the leading edge of sheet SH1 is detected by a sheet sensor (not shown) located upstream of line sensor 71 in the sheet conveying path R11 (see FIG. 1) in the conveying direction D11, the reading processing unit 84 starts reading the shape of sheet SH1 using the shape reading unit 7. This causes the shape reading unit 7 to output the line data at the imaging period. Furthermore, the reading processing unit 84 ends reading the shape of sheet SH1 using the shape reading unit 7 when a predetermined time has elapsed since the trailing edge of sheet SH1 was detected by the sheet sensor. The predetermined time is set so that reading of the shape of sheet SH1 by the shape reading unit 7 ends after the trailing edge of sheet SH1 passes a position facing line sensor 71. The reading processing unit 84 then acquires each of the line data output from the shape reading unit 7 during the period in which the shape of sheet SH1 is read by the shape reading unit 7. In other words, the shape data X10 is data composed of the multiple line data output from the shape reading unit 7 during the period in which the shape reading unit 7 reads the shape of sheet SH1.

[0047] FIG. 6 shows an example of shape data X10. The shape data X10 shown in FIG. 6 is shape data X10 acquired by the reading processing unit 84 when the posture of the correction unit 61 is inclined with respect to the conveying direction D11. The shape data X10 includes a sheet area X11 indicating the sheet SH1. The sheet area X11 is an area formed by pixels indicating the presence of the sheet SH1. The outside of the sheet area X11 in the shape data X10 is formed by pixels indicating the absence of the sheet SH1. Note that the third direction D31 shown in FIG. 6 corresponds to the conveying direction D11. Furthermore, the fourth direction D32 shown in FIG. 6 corresponds to the width direction D12 (see FIG. 2). Furthermore, the fifth direction D33 shown in FIG. 6 corresponds to the first direction D21 (see FIG. 3).

[0048] The acquisition processing unit 85 acquires the inclination angle of the side edge of the sheet SH1 that has passed through the correction unit 61 with respect to the conveyance direction D11, based on the reading result by the reading processing unit 84.

[0049] For example, based on the reading result by the reading processing unit 84, the acquisition processing unit 85 acquires the inclination angle of the side end portion of the sheet SH1 that has passed through the correction unit 61 in the first direction D21 (see FIG. 3) with respect to the conveying direction D11.

[0050] Specifically, the acquisition processing unit 85 acquires the inclination angle θ1 (see Figure 6) of the end portion in the fifth direction D33 in the sheet area X11 contained in the shape data X10 (see Figure 6) acquired by the reading processing unit 84 with respect to the third direction D31 as the inclination angle of the side end portion on the first direction D21 (see Figure 3) side of the sheet SH1 that has passed through the correction unit 61 with respect to the conveying direction D11.

[0051] For example, each time the reading processing unit 84 acquires the line data, the acquisition processing unit 85 determines whether the acquired line data includes a pixel indicating the presence of sheet SH1. The acquisition processing unit 85 measures the elapsed time from timing T0 (see FIG. 6) when it is first determined that the line data includes a pixel indicating the presence of sheet SH1. The acquisition processing unit 85 acquires a distance L1 (see FIG. 6) (number of pixels) from an end of the line data opposite the fifth direction D33, acquired at timing T1 (see FIG. 6) when the elapsed time from timing T0 reaches a predetermined first time, to an end of the sheet area X11 in the fifth direction D33. The acquisition processing unit 85 acquires a distance L2 (see FIG. 6) (number of pixels) from an end of the line data opposite the fifth direction D33, acquired at timing T2 (see FIG. 6) when the elapsed time from timing T0 reaches a second time longer than the first time, to an end of the sheet area X11 in the fifth direction D33. Then, the acquisition processing unit 85 calculates the tilt angle θ1 based on the difference between the distance L2 and the distance L1 and the distance (number of pixels) corresponding to the time from the timing T1 to the timing T2.

[0052] The adjustment processing unit 86 adjusts the inclination angle of the facing surface 61A with respect to the transport direction D11 based on the results obtained by the acquisition processing unit 85.

[0053] For example, the adjustment processing unit 86 uses predetermined table data to convert the inclination angle acquired by the acquisition processing unit 85 into a drive amount for the angle changing unit 63. The table data is data that defines a correspondence relationship between the inclination angle acquired by the acquisition processing unit 85 and the drive amount for the angle changing unit 63 so that the inclination angle of the facing surface 61A with respect to the conveying direction D11 can be set to zero. The table data is stored in advance in a non-volatile storage device such as the ROM 82.

[0054] Then, the adjustment processing unit 86 controls the driving of the angle changing unit 63 based on the driving amount of the angle changing unit 63 acquired using the table data.

[0055] [Tilt angle adjustment processing] 5, an example of the procedure of the tilt angle adjustment process executed by the control unit 9 in the image forming apparatus 100 will be described. Here, steps S11, S12, etc. represent the numbers of the processing procedures (steps) executed by the control unit 9. The tilt angle adjustment process is executed when an instruction to execute the tilt angle adjustment process is input by a user's operation on the operation display unit 8.

[0056] <Step S11> First, in step S11, the control section 9 executes a conveying process to convey the sheet SH1 along the sheet conveying path R11.

[0057] <Step S12> In step S12, the control unit 9 executes a reading process to read the outer shape of the sheet SH1 that has passed through the correction unit 61. The process of step S12 is executed by the reading processing unit 84 of the control unit 9.

[0058] Specifically, the control unit 9 uses the line sensor 71 to acquire shape data X10 (see FIG. 6) that indicates the shape of the sheet SH1 that has passed through the correction unit 61.

[0059] <Step S13> In step S13, the control unit 9 executes an acquisition process to acquire the inclination angle with respect to the conveying direction D11 of the side edge of the sheet SH1 that has passed through the correction unit 61, based on the reading result of the reading process. The process of step S13 is executed by the acquisition processing unit 85 of the control unit 9.

[0060] Specifically, the control unit 9 acquires the inclination angle θ1 (see Figure 6) of the end portion in the fifth direction D33 in the sheet area X11 contained in the shape data X10 (see Figure 6) acquired by the reading process as the inclination angle of the side end portion on the first direction D21 (see Figure 3) side of the sheet SH1 that has passed through the correction unit 61 with respect to the conveying direction D11.

[0061] <Step S14> In step S14, the control unit 9 determines whether the tilt angle acquired by the acquisition process is within a predetermined allowable range. For example, the allowable range is a range of ±5 degrees centered around 0 degrees. Note that the allowable range may be any range centered around 0 degrees.

[0062] If the control unit 9 determines that the tilt angle acquired by the acquisition process is within the allowable range (Yes in S14), it ends the tilt angle adjustment process. If the tilt angle acquired by the acquisition process is not within the allowable range (No in S14), the control unit 9 shifts the process to step S15.

[0063] <Step S15> In step S15, the control unit 9 determines whether the number of times the process of step S16 has been executed exceeds a predetermined upper limit. For example, the upper limit is 3 times. Note that the upper limit may be any number.

[0064] Here, if the control unit 9 determines that the number of times the process of step S16 has been executed exceeds the upper limit (Yes in S15), it shifts the process to step S17. On the other hand, if the number of times the process of step S16 has been executed does not exceed the upper limit (No in S15), it shifts the process to step S16.

[0065] <Step S16> In step S16, the control unit 9 executes an adjustment process to adjust the tilt angle of the opposing surface 61A with respect to the conveying direction D11 based on the results of the acquisition process. The process of step S16 is executed by the adjustment processing unit 86 of the control unit 9.

[0066] For example, the control unit 9 uses the table data to convert the tilt angle acquired by the acquisition process into a drive amount for the angle change unit 63. Then, the control unit 9 controls the drive of the angle change unit 63 based on the drive amount for the angle change unit 63 acquired using the table data.

[0067] <Step S17> In step S17, the control unit 9 notifies the user that the adjustment of the inclination angle of the opposing surface 61A with respect to the conveying direction D11 has failed.

[0068] For example, the control unit 9 causes the operation display unit 8 to display a message indicating that adjustment of the inclination angle of the opposing surface 61A with respect to the conveying direction D11 has failed.

[0069] In this way, the image forming apparatus 100 includes the angle changing unit 63 that changes the inclination angle of the opposing surface 61A with respect to the conveying direction D11. This makes it possible to prevent the posture of the correction unit 61 from being inclined with respect to the conveying direction D11 using the angle changing unit 63.

[0070] Furthermore, in the image forming apparatus 100, the outer shape of the sheet SH1 that has passed through the correction unit 61 is read, and based on the reading result of the outer shape of the sheet SH1, the inclination angle of the side edge of the sheet SH1 that has passed through the correction unit 61 with respect to the conveying direction D11 is obtained, and based on the obtained inclination angle, the inclination angle of the opposing surface 61A with respect to the conveying direction D11 is adjusted. This makes it possible to automatically adjust the inclination angle of the opposing surface 61A with respect to the conveying direction D11.

[0071] Furthermore, in image forming apparatus 100, the inclination angle of the side edge of sheet SH1 that has passed through correction unit 61 in the first direction D21 (see FIG. 3) with respect to the conveying direction D11 is acquired based on the results of reading the outer shape of sheet SH1. This makes it possible to avoid a decrease in the adjustment accuracy of the inclination angle of opposing surface 61A with respect to the conveying direction D11 when both side edges of sheet SH1 are non-parallel, compared to a configuration in which the inclination angle of the side edge of sheet SH1 that has passed through correction unit 61 with respect to the conveying direction D11 on the opposite side to the first direction D21 with respect to the conveying direction D11 is acquired.

[0072] In addition, the processes of steps S12, S13, and S16 of the inclination angle adjustment process may be performed each time a predetermined number of sheets SH1 on which an image is to be formed are transported when an image formation process is performed to form an image on sheet SH1.

[0073] [Notes on the Invention] The following will provide an outline of the invention extracted from the above-described embodiment. Note that the configurations and processing functions described in the following supplementary notes can be selected and combined as desired.

[0074] <Appendix 1> A sheet conveying device comprising: a first conveying section that conveys a sheet; a correction section that is arranged upstream of the first conveying section in a conveying direction of the sheet by the first conveying section and has an opposing surface that faces a side end of the sheet on a first direction side that is perpendicular to the conveying direction; a second conveying section that is arranged upstream of the correction section in the conveying direction and conveys the sheet in a second direction toward the opposing surface; and an angle change section that changes the inclination angle of the opposing surface with respect to the conveying direction.

[0075] <Appendix 2> 10. An image forming apparatus comprising: the sheet conveying device according to claim 1; and an image forming unit that forms an image on the sheet conveyed by the first conveying unit.

[0076] <Appendix 3> An image forming apparatus as described in Appendix 2, comprising: a reading processing unit that reads the outline of the sheet that has passed through the correction unit; an acquisition processing unit that acquires the inclination angle of the side edge of the sheet that has passed through the correction unit with respect to the conveying direction based on the reading result by the reading processing unit; and an adjustment processing unit that adjusts the inclination angle of the opposing surface with respect to the conveying direction based on the acquisition result by the acquisition processing unit.

[0077] <Appendix 4> The image forming apparatus of claim 3, wherein the acquisition processing unit acquires the inclination angle of the side end portion of the sheet on the first direction side relative to the conveying direction after passing through the correction unit based on the reading result by the reading processing unit. [Explanation of symbols]

[0078] 1 chassis 2 Paper feed section 3 Image forming unit 4 Transport unit 5 Paper output section 6 Posture correction department 7 Shape reading unit 8 Operation display section 9 Control Unit 11 First cabinet 12 Second enclosure 13 Third cabinet 21 Paper cassette 22 Pickup roller 23 Paper feed roller 30 Recording head 30A nozzle 31 Line Head 32 Line Head 33 Line Head 34 Line Head 35 Head Frame 41 Conveyor belt 42 First tension roller 43 Second tension roller 44 Third tension roller 45 Transport frame 51 First paper ejection roller 52 Second paper ejection roller 53 Paper output tray 61 Orthodontics Department 62 Transport roller 63 Angle change section 71 Line Sensor 72 AFE circuits 81 CPU 82 ROM 83 RAM 84 Reading processing section 85 Acquisition processing unit 86 Adjustment processing section 100 Image forming device

Claims

1. a first conveying unit that conveys a sheet; a correction unit provided upstream of the first conveying unit in a conveying direction of the sheet by the first conveying unit, the correction unit having an opposing surface opposing a side end of the sheet on a first direction side perpendicular to the conveying direction; a second conveying unit provided upstream of the correction unit in the conveying direction and configured to convey the sheet in a second direction toward the opposing surface; an angle changer that changes the inclination angle of the opposing surface with respect to the conveying direction; A sheet conveying device comprising:

2. The sheet conveying device according to claim 1 ; an image forming unit that forms an image on the sheet conveyed by the first conveying unit; An image forming apparatus comprising:

3. a reading processing unit that reads the outer shape of the sheet that has passed through the correction unit; an acquisition processing unit that acquires an inclination angle of the side edge of the sheet that has passed through the correction unit with respect to the conveying direction based on the reading result by the reading processing unit; an adjustment processing unit that adjusts the tilt angle of the opposing surface with respect to the conveyance direction based on the result of acquisition by the acquisition processing unit; The image forming apparatus according to claim 2 , further comprising:

4. The acquisition processing unit acquires an inclination angle of a side end portion of the sheet on the first direction side with respect to the conveying direction, the side end portion having passed through the correction unit, based on a reading result by the reading processing unit. The image forming apparatus according to claim 3 .

Images