Image reading device, image forming system, and program

Abstract

To improve a reading accuracy of an image reading part that moves in a width direction of a sheet.SOLUTION: An image reading device 30 is an image reading device that reads image information on a sheet (sheet S) after an image is formed, and includes: an image reading part 32 that is movable in a sheet width direction (sheet width direction) orthogonal to a sheet conveyance direction (sheet conveyance direction) and reads the image information on the sheet; first conveyance means (first conveyance roller 34a) that is provided on an upstream side of the image reading part 32 in the sheet conveyance direction and conveys the sheet; second conveyance means (second conveyance roller 34b) that is provided on a downstream side of the image reading part 32 in the sheet conveyance direction and conveys the sheet; and a control part (third control part 31) that stops the second conveyance means after stopping the first conveyance means when switching from a conveyance state in which the first conveyance means and the second conveyance means cooperate to convey the same sheet to a stop state in the conveyance of the sheet.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] BACKGROUND ART Conventionally, there is known an image reading device that can reduce the possibility of sheet jamming while allowing the image reading means to move in the width direction to read image information on a sheet (see, for example, Patent Document 1). An image reading device is known that stabilizes the positions of a colorimeter and a sheet of paper by using a guide plate that guides the paper and an opposing member that presses against the reference surface of the colorimeter through the paper, bringing the paper into contact with the reference surface (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-182686 [Patent Document 2] Japanese Patent Application Publication No. 2018-170696 Summary of the Invention [Problem to be solved by the invention]

[0004] The image reading device disclosed in the above-mentioned Patent Document 1 is provided with an upstream guide shutter and a downstream guide shutter to reduce the possibility of jamming. In this image reading device, when the image reading means reads image information from a sheet, the guide shutters are operated in a double-door manner. This may cause the sheet to be in an unstable position relative to the image reading means, which may reduce the reading accuracy of the image reading means. The image reading device disclosed in Patent Document 2 reads only patch images formed in the center of the paper, and therefore does not assume that the colorimeter will be moved in the width direction. Therefore, if the colorimeter is moved in the width direction in this image reading device to read patch images formed in areas other than the center of the paper, wrinkles may occur in the paper or the paper may not contact the reference surface properly.

[0005] The object of the present invention has been made in consideration of the above-mentioned problems, and is to provide an image reading device, an image forming system, and a program that can improve the reading accuracy of an image reading unit that moves in the width direction of the paper. [Means for solving the problem]

[0006] In order to solve the above problem, the image reading device according to claim 1 is An image reading device that reads image information on a sheet after an image is formed, an image reading unit that is movable in a sheet width direction perpendicular to a sheet conveying direction and that reads image information of the sheet; a first conveying unit that is provided upstream of the image reading unit in the sheet conveying direction and that conveys the sheet; a second conveying unit provided downstream of the image reading unit in the sheet conveying direction and configured to convey the sheet; a control unit that stops the second conveying means after stopping the first conveying means when switching from a conveying state in which the first conveying means and the second conveying means cooperate to convey the same sheet to a stopped state in conveying the sheet; Equipped with.

[0007] The invention described in claim 2 is the image reading device described in claim 1, In the stopped state, the image reading unit moves in the sheet width direction to read the image information.

[0008] The invention described in claim 3 is the image reading device described in claim 1, The control unit determines the time from when the first conveying means is stopped to when the second conveying means is stopped based on the type and / or basis weight of the sheet.

[0009] The invention described in claim 4 is the image reading device described in claim 1, a pressing unit that presses a background member provided at a position facing the image reading unit toward the image reading unit; The image reading unit moves in the sheet width direction while sandwiching the sheet between itself and the background member pressed by the pressing unit.

[0010] The invention described in claim 5 is the image reading device described in claim 4, The control unit determines, based on the type and / or basis weight of the sheet, whether to sandwich the sheet between the background member pressed by the pressing unit and the image reading unit when moving the image reading unit in the sheet width direction, or whether to not press the background member with the pressing unit.

[0011] The invention described in claim 6 is the image reading device described in claim 1, The image reading unit includes a reducing portion at a portion that contacts the sheet, the reducing portion reducing sliding resistance during movement in the sheet width direction.

[0012] The invention described in claim 7 is the image reading device described in claim 4, The control unit reduces the sliding resistance when the image reading unit moves in the sheet width direction by making the pressing force of the pressing unit smaller than the pressing force when the image reading unit reads the image information.

[0013] The invention described in claim 8 is the image reading device described in claim 1, The first conveying means corrects the skew of the sheet.

[0014] The invention described in claim 9 is the image reading device described in claim 1, The conveying force of the first conveying means is greater than the conveying force of the second conveying means.

[0015] The invention described in claim 10 is the image reading device described in claim 1, The image reading unit includes a spectrophotometer.

[0016] The image forming system according to claim 11, an image forming device for forming an image on the sheet; the image reading device according to claim 1, which is disposed downstream of the image forming device in the sheet conveying direction; Equipped with.

[0017] The invention described in claim 12 is the image forming system described in claim 11, The image forming device forms, on the sheet, an adjustment image that is two-dimensionally arranged as the image information.

[0018] The program according to claim 13 comprises: An image reading device that reads image information on a sheet after an image is formed, an image reading unit that is movable in a sheet width direction perpendicular to a sheet conveying direction and that reads image information of the sheet; a first conveying unit that is provided upstream of the image reading unit in the sheet conveying direction and that conveys the sheet; a second conveying unit provided downstream of the image reading unit in the sheet conveying direction and configured to convey the sheet; A computer of an image reading device comprising: When switching from a conveying state in which the first conveying means and the second conveying means cooperate to convey the same sheet to a stopped state in conveying the sheet, the control unit functions to stop the second conveying means after stopping the first conveying means. [Effects of the Invention]

[0019] According to the present invention, it is possible to improve the reading accuracy of the image reading unit that moves in the width direction of the paper. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 1 is a schematic side view of an image forming system. [Figure 2] FIG. 2 is a block diagram showing a functional configuration of the image forming system. [Figure 3A] FIG. 2 is a top view of a portion indicated by A in FIG. [Figure 3B] FIG. 2 is a side view of a portion indicated by A in FIG. [Figure 4] FIG. 10 is a diagram illustrating an example of a chart image. [Figure 5A] FIG. 4 is a diagram illustrating an example of a guide plate of an image reading unit. [Figure 5B] 5A and 5B are diagrams illustrating an example of a guide plate and rollers of an image reading unit. [Figure 5C] 5A and 5B are diagrams illustrating an example of a guide plate and rollers of an image reading unit. [Figure 6] 10 is a flowchart showing a control procedure for image reading processing. [Figure 7] 10 is a flowchart showing a control procedure for pre-reading processing. [Figure 8] 10 is a flowchart showing a control procedure for odd-numbered line reading processing. [Figure 9] 10 is a flowchart showing a control procedure for even-numbered row reading processing. [Figure 10A] 10A and 10B are diagrams illustrating an example in which an edge detection unit detects the leading edge of a sheet. [Figure 10B] 10A and 10B are diagrams illustrating an example in which the image reading unit is moved to a reading start position for odd-numbered lines. [Figure 10C] FIG. 10 is a diagram illustrating an example in which the image reading unit is moved to a retracted position. [Figure 10D] FIG. 10 is a diagram showing an example in which the paper is transported by one patch row. [Figure 10E] 10A and 10B are diagrams illustrating an example in which the image reading unit is moved to a reading start position for an even-numbered line. [Figure 10F] 10A and 10B are diagrams illustrating an example in which the image reading unit is moved to a retracted position after the patch has been read; DETAILED DESCRIPTION OF THE INVENTION

[0021] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An image reading apparatus and an image forming system according to embodiments of the present invention will be described below with reference to the accompanying drawings. However, the present invention is not limited to the illustrated examples.

[0022] [Image formation system configuration] Fig. 1 is a side view showing a schematic configuration of an image forming system 1. Fig. 2 is a block diagram showing a functional configuration of the image forming system 1. In the following description, the X direction, Y direction, and Z direction refer to the directions shown in Fig. 1. In addition, in the following description, the X direction, Y direction, and Z direction will be referred to as the paper width direction, paper transport direction, and up-down direction, respectively.

[0023] 1 and 2, the image forming system 1 includes a paper feeder 10, an image forming device 20, an image reading device 30, and a post-processing device 40. The paper feeder 10, the image forming device 20, the image reading device 30, and the post-processing device 40 are arranged in this order toward the downstream side in the paper transport direction. Therefore, paper (sheets) are transported continuously from the paper feeder 10 to the post-processing device 40 via the image forming device 20 and the image reading device 30. The paper feeder 10, the image forming device 20, the image reading device 30, and the post-processing device 40 are interconnected so as to be able to perform data communication with one another.

[0024] (Paper feeder) The paper feeder 10 supplies stored paper to the image forming apparatus 20. The paper feeder 10 includes a first control unit 11, a transport unit 12, and a paper feed unit 13.

[0025] The first control unit 11 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory). The CPU of the first control unit 11 reads various processing programs stored in the ROM, loads them into the RAM, and performs centralized control of the operations of each unit of the sheet feeding device 10 according to the loaded programs. For example, the first control unit 11 transports paper from one of the paper feed trays 131 to 133 of the sheet feeding unit 13 to the image forming device 20 according to the job.

[0026] The transport unit 12 includes a transport path 121 and transport rollers (not shown). The transport path 121 connects the paper feed unit 13 to the image forming device 20. The transport rollers transport paper to the transport path 121. The paper feed unit 13 has paper feed trays 131 to 133 that store paper according to predetermined paper types, sizes, etc.

[0027] (Image forming device) The image forming device 20 is located downstream of the paper feed device 10 in the paper transport direction and upstream of the image reading device 30 in the paper transport direction. The image forming device 20 acquires image data by reading an image from a document or by receiving the image data from an external device (not shown). The image forming device 20 forms an image based on the acquired image data. After forming the image, the image forming device 20 transports the paper to the image reading device 30.

[0028] The image forming apparatus 20 includes an operation unit 21, a display unit 22, a document image reading unit 23, an image forming unit 24, a second control unit 25, a storage unit 26, a communication unit 27, and an image processing unit .

[0029] The operation unit 21 includes, for example, a touch panel formed to cover the display screen of the display unit 22, numeric buttons, a start button, and various other operation buttons. The operation unit 21 outputs an operation signal to the second control unit 25 based on an operation by the user.

[0030] The display unit 22 includes an LCD (Liquid Crystal Display) etc. The display unit 22 displays various screens in accordance with instructions of a display signal input from the second control unit 25.

[0031] The document image reading unit 23 includes an automatic document feeder (ADF), a scanner, etc. The document image reading unit 23 reads the image of the document and outputs the image data obtained to the second control unit 25.

[0032] Based on the acquired image data, the image forming unit 24 forms an image on a sheet of paper conveyed from the paper feeder 10. In this embodiment, the sheet of paper is a sheet. The image forming unit 24 includes, for example, a photosensitive drum, an intermediate transfer belt 242, a secondary transfer roller 243, and a fixing unit 244.

[0033] The photosensitive drums of this embodiment include photosensitive drums that individually correspond to the colors of yellow (Y), magenta (M), cyan (C), and black (K), for example. That is, the photosensitive drums include photosensitive drums 241Y, 241M, 241C, and 241K. After uniformly charging the photosensitive drum 241Y, the image forming unit 24 scans and exposes it with a laser beam based on yellow image data to form an electrostatic latent image. Next, the image forming unit 24 applies yellow toner to the electrostatic latent image on the photosensitive drum 241Y to develop it. The photosensitive drums 241M to 241K form images in the same way as the photosensitive drum 241Y, except that they handle different colors, so their description will be omitted.

[0034] The image forming unit 24 transfers the toner images of each color formed on the photosensitive drums 241Y to 241K onto the intermediate transfer belt 242. This transfer onto the intermediate transfer belt 242 is a primary transfer. That is, the image forming unit 24 forms a color toner image on the intermediate transfer belt 242 by superimposing the toner images of four colors. The image forming unit 24 transfers the color toner images on the intermediate transfer belt 242 all at once onto a sheet of paper by a secondary transfer roller 243. This transfer onto the sheet of paper is a secondary transfer. The fixing unit 244 includes a heating roller and a pressure roller. The heating roller heats the paper onto which the color toner image has been transferred. The pressure roller presses the paper heated by the heating roller. The color toner image is fixed to the paper by the heating and pressure applied by the fixing unit 244.

[0035] The second control unit 25 includes a CPU, a ROM, and a RAM. The CPU of the second control unit 25 reads various processing programs stored in the ROM, loads them into the RAM, and performs centralized control of the operations of the various units of the image forming apparatus 20 according to the loaded programs.

[0036] The storage unit 26 is a non-volatile storage device such as a hard disk drive (HDD) or a semiconductor memory. The storage unit 26 stores data such as program data, various setting data, and image data in a manner that allows the second control unit 25 to read and write the data. The storage unit 26 stores information on the paper feed trays 131 to 133 and the basis weight, size, type, and other information of the paper stored therein in association with each other.

[0037] The communication unit 27 transmits and receives various data to and from external devices such as personal computers connected to a communication network such as a LAN (Local Area Network) or a WAN (Wide Area Network), etc. The communication unit 27 includes a communication control card such as a LAN card.

[0038] The image processing unit 28 performs image processing necessary for image data before image formation. The image data includes image data stored in the storage unit 26, image data obtained by reading an original document with the original document image reading unit 23, and image data input from an external device. The image processing unit 28 transmits the image data after image processing to the image forming unit 24. The image processing includes gradation processing, halftone processing, color conversion processing, etc. The gradation processing is a process of converting the gradation values ​​of each pixel of the image data into corrected gradation values ​​so that the density characteristics of the image formed on the paper match the target density characteristics. The halftone processing is an error diffusion process, a screen process using an ordered dithering method, etc. The color conversion processing is a process of converting each RGB gradation value into each CMYK gradation value. The above-mentioned processing of the image processing unit 28 may be realized by a program executed by the CPU of the second control unit 25.

[0039] (Image reader) The image reading device 30 is located downstream of the image forming device 20 in the paper transport direction and upstream of the post-processing device 40 in the paper transport direction. Fig. 3A shows a top view of the portion of image reading device 30 indicated by A in Fig. 1. Fig. 3B shows a side view of the portion of image reading device 30 indicated by A in Fig. 1. The image reading device 30 includes a third control unit 31, an image reading unit 32, a drive unit 33, a conveying unit 34, a backing unit 35, an edge detection unit 36, and a paper detection unit 37. The image reading device 30 measures the color of the chart image on the paper conveyed from the image forming device 20 and acquires the color measurement results.

[0040] The third control unit 31 includes a CPU, a ROM, and a RAM. The CPU of the third control unit 31 reads various processing programs stored in the ROM, loads them into the RAM, and performs centralized control of the operations of the various units of the image reading device 30 according to the loaded programs.

[0041] The image reading unit 32 is provided downstream of the image forming device 20 in the paper transport path, and is capable of reading the paper after an image has been formed on it before the paper is discharged to the outside. The image reading unit 32 can read only a partial area in a direction perpendicular to the paper transport direction and parallel to the paper surface (paper width direction). The image reading unit 32 is moved in the paper width direction (X-axis direction) by the drive unit 33, and reads the image information of the paper by measuring the color of a chart image (adjustment image) formed on the paper transported along the paper transport path. The image reading unit 32 is movable in the paper width direction from a standby position L1 to a retracted position L2. The standby position L1 is located in an area outside the paper passage range R on the rear side in the paper width direction (positive X-axis direction side). The retracted position L2 is located in an area outside the paper passage range R on the front side in the paper width direction (negative X-axis direction side). The paper passage range R is the paper transport area.

[0042] A description will be given of a chart image formed on paper S by image forming apparatus 20. Fig. 4 is a diagram showing an example of the chart image. The chart image is a calibration chart made up of a plurality of patches P whose combinations of gradation values ​​are determined in advance. 4 is an image configured by arranging a plurality of patch rows, each row consisting of a plurality of patches P aligned in a line along the paper width direction, in parallel in the paper transport direction. In other words, the image forming apparatus 20 forms an adjustment image, which is two-dimensionally arranged as image information, on the paper. In the example of Fig. 4, the patch P is square, but the patch P may be other shapes such as rectangular. The shape and dimensions of each patch P are the same. Each patch P or each patch row may be formed without gaps, or may have gaps. It is preferable that the combination of gradation values ​​that indicates the hue of each patch P is different for each patch P.

[0043] The chart image is preferably formed at a position where it can be read by the image reading unit 32 when the paper S is sandwiched between the first transport roller 34a and the second transport roller 34b (described later). In this case, the chart image can be read while the first transport roller 34a and the second transport roller 34b apply an appropriate tension to the paper S, thereby improving the reading accuracy. The chart image does not have to be formed at a position where it can be read by the image reading unit 32 when the paper S is held between the first transport roller 34a and the second transport roller 34b. The chart image may be formed at a position where waste paper can be reduced compared to when the chart image is formed at a position where it can be read by the image reading unit 32 when the paper S is held between the first transport roller 34a and the second transport roller 34b.

[0044] The image forming unit 24 of the image forming device 20 forms a chart image on one side of a sheet of paper S. The image reading unit 32 is equipped with a spectrophotometer and measures (reads) the color of each patch P of the chart image formed by the image forming unit 24. Therefore, the image reading unit 32 can measure colors with higher accuracy than an image reading unit configured with a color scanner. The image reading unit 32 individually measures all patches P of the chart image and outputs the results to the third control unit 31. The third control unit 31 compares the gradation values ​​of each patch P defined in the image data of the chart image with the gradation values ​​measured by the image reading unit 32. Next, the third control unit 31 creates a color profile based on this comparison and sends it to the image forming apparatus 20. The second control unit 25 corrects the hue by referring to the color profile when the image forming unit 24 forms an image.

[0045] As shown in FIG. 5A, the image reading unit 32 includes a guide plate 321 on the lower surface (surface facing the negative Z-axis direction) of the reading main body 32a. The guide plate 321 is a flat plate member having a substantially rectangular shape. The guide plate 321 is provided with an opening 321a that allows the spectrophotometer of the image reading unit 32 to face the paper S through the guide plate 321. The opening 321a has, for example, a circular shape. The lower surface of the guide plate 321 is flat and forms a colorimetry reference surface r1. The guide plate 321 abuts against the paper S at the colorimetry reference surface r1. An inclined surface f1 may be provided on the lower surface of the guide plate 321 other than the colorimetry reference surface r1 to smoothly guide the paper S being transported. By providing the image reading unit 32 with the guide plate 321, the guide plate 321 prevents the paper from floating up when the image reading unit 32 moves in the paper width direction on the paper, so that the image reading unit 32 can move smoothly on the paper. In the image reading unit 32, the reading main body 32a and the guide plate 321 may be integrally formed. The image reading unit 32 may include a sliding sheet instead of the guide plate 321.

[0046] 5B and 5C, the image reading unit 32 may include a guide plate 321 and rollers 322 on the lower surface of the reading main body 32a. The image reading unit 32 comes into contact with the paper S at the rollers 322. The rollers 322 are rotatable in the paper width direction, which is the movement direction of the image reading unit 32. When the image reading unit 32 is provided with the rollers 322, the rollers 322 rotate when the image reading unit 32 moves in the paper width direction on the paper, so that the image reading unit 32 can move smoothly on the paper.

[0047] As described above, the reduction unit, which is the guide plate 321 or the roller 322 of the image reading unit 32, allows the image reading unit 32 to move smoothly over the paper, thereby reducing the occurrence of paper jams associated with the movement of the image reading unit 32. In other words, the reduction unit reduces the sliding resistance force of the image reading unit 32 when it moves in the paper width direction. Specifically, it is preferable to provide the image reading unit 32 with a reduction unit that reduces the sliding resistance force of the image reading unit 32 when it moves in the paper width direction to within a range of one-fourth to one-tenth of the conveying force of the first conveying roller 34a and the second conveying roller 34b.

[0048] The drive unit 33 slides the image reading unit 32 in the paper width direction so that the image reading unit 32 is positioned at a desired reading position when the image reading unit 32 individually measures a plurality of patches P that are regularly arranged in the paper width direction in a chart image formed on paper. The drive source of the drive unit 33 is, for example, a stepping motor.

[0049] The transport section 34 has a paper transport path that connects the image forming device 20 to the post-processing device 40, and a plurality of transport rollers that extend in the paper width direction and transport paper on the paper transport path. The plurality of transport rollers include a first transport roller 34a (first transport means) located upstream in the paper transport direction from the image reading unit 32, and a second transport roller 34b (second transport means) located downstream in the paper transport direction from the image reading unit 32. The first transport roller 34a and the second transport roller 34b are driven by, for example, a stepping motor or the like. The paper conveying force of the second conveying roller 34b is smaller than the paper conveying force of the first conveying roller 34a.

[0050] The first transport roller 34a and a transport roller located upstream of the first transport roller 34a in the paper transport direction correct the skew of the paper S transported on the paper transport path as a registration operation. It is preferable to make the size of the patch P of the chart image smaller in order to shorten the reading time by the image reading unit 32 and reduce the amount of paper on which the chart image is formed. Even when the patch P of the chart image is relatively small in this way, correcting the skew of the paper can improve the paper transport accuracy, thereby suppressing errors in reading the patch P by the image reading unit 32.

[0051] The backing portion 35 includes a background member 351, a pressing portion 352, and the like. The background member 351 is provided at a position facing the position of the image reading unit 32 when measuring the color of a chart image formed on the paper S. Since the background member 351 is a member that forms the background of the paper S, it is preferable that the surface of the background member 351 facing the image reading unit 32 is white or black.

[0052] Under the control of the third control unit 31, the pressing unit 352 moves the background member 351 in the vertical direction (Z-axis direction). Specifically, when the chart image formed on the paper S is measured by the image reading unit 32, the pressing unit 352 raises and presses the background member 351 in a direction toward the image reading unit 32 (positive direction of the Z axis). This allows the pressed background member 351 to abut the paper S against the image reading unit 32. Therefore, the attitude of the paper S relative to the image reading unit 32 can be stabilized, and the reading accuracy of the image reading unit 32 can be improved. On the other hand, when the paper S is transported on the background member 351, the pressing unit 352 lowers the background member 351 in the negative Z-axis direction to release the pressure. In other words, the pressing unit 352 moves the background member 351 away from the paper transport path. This prevents the background member 351 from interfering with the transport of the paper, thereby improving the transportability of the paper.

[0053] The edge detection unit 36 ​​is provided downstream of the first transport roller 34a in the paper transport direction and upstream of the image reading unit 32 in the paper transport direction. The edge detection unit 36 ​​detects the position of the sheet S in the sheet width direction. More specifically, the edge detection unit 36 ​​detects the position of one side edge sl in the sheet width direction. The edge detection unit 36 ​​outputs the detection result of the position of the sheet S to the third control unit 31. The edge detection unit 36 ​​is a linear image sensor such as a CIS (Contact Image Sensor). As shown in Fig. 3A, the edge detection unit 36 ​​is arranged so that its linear detection range is parallel to the paper width direction and faces the paper S being transported.

[0054] The paper detection unit 37 is provided downstream of the second transport roller 34b in the paper transport direction. The sheet detection unit 37 detects the presence or absence of a sheet at a position downstream in the sheet transport direction of the second transport roller 34b, where the sheet detection unit 37 is installed. The sheet detection unit 37 outputs the detection result of the sheet S to the third control unit 31. When the paper detection unit 37 detects the presence of paper, that is, when it detects that paper is present downstream of the second transport roller 34b in the paper transport direction, the third control unit 31 determines that the paper is being clamped by the second transport roller 34b.

[0055] (Post-treatment device) The post-processing device 40 is located downstream of the image reading device 30 in the paper transport direction, and performs post-processing on the paper transported from the image reading device 30. The post-processing device 40 includes a fourth control unit 41, a post-processing unit 42, a conveying unit 43, and a paper discharge tray 44.

[0056] The fourth control unit 41 includes a CPU, a RAM, a ROM, and the like. The CPU of the fourth control unit 41 reads out various processing programs stored in the ROM and loads them into the RAM. The fourth control unit 41 comprehensively controls the operation of the post-processing device 40 in cooperation with the various programs loaded into the RAM.

[0057] The post-processing unit 42 performs post-processing on the paper conveyed from the image reading device 30. Examples of the post-processing include cutting, folding, perforating, creasing, foil stamping, varnishing, various types of bookbinding, and the like.

[0058] The conveying section 43 includes a plurality of roller pairs, and conveys the paper conveyed from the image reading device 30 to the post-processing section . Next, the conveying section 43 discharges the paper that has been subjected to post-processing by the post-processing section 42 onto the paper discharge tray 44 .

[0059] [Image formation system operation] Next, a description will be given of the operation of the image forming system 1. The image reading process executed by the image reading device 30 will be described with reference to Fig. 6. Fig. 6 is a flowchart showing the control procedure of the image reading process.

[0060] (Image reading processing) The third control unit 31 of the image reading device 30 executes the pre-reading process shown in FIG. 7 (step S1).

[0061] (Pre-reading process) The third control section 31 controls the pressing section 352 of the backing section 35 to lower the background member 351, thereby retracting the background member 351 from the paper transport path (step A1). Next, the third control unit 31 controls the drive unit 33 to move the image reading unit 32 to the standby position L1 (step A2). Next, the third control unit 31 causes the conveying unit 34 to convey the paper S, on which the chart image has been formed and which has been conveyed from the image forming device 20, through the image reading device 30 (step A3).

[0062] Next, the third control unit 31 calculates a post-detection transport distance based on information about the paper and information about the chart image formed on the paper (step A4). The information about the paper includes the size of the paper. The information about the chart image includes the size of the chart image, the position where the chart image is formed on the paper, etc. The post-detection transport distance is the distance the paper is transported from when the paper detection unit 37 detects the presence of paper until the first line of the chart image on the paper to be read reaches the reading position of the image reading unit 32. The first line of the chart image is the first line P1 of the patch P shown in FIG. 10A.

[0063] Next, when the paper sheet being transported reaches the first transport roller 34a, the third control unit 31 performs a registration operation using the first transport roller 34a and a transport roller located upstream of the first transport roller 34a in the paper transport direction to correct the skew of the paper sheet S (step A5). Specifically, the third control unit 31 corrects the skew of the leading edge of the paper sheet (downstream in the paper transport direction) by transporting the paper sheet using a transport roller located upstream of the first transport roller 34a in the paper transport direction while keeping the first transport roller 34a stopped. Next, the third control unit 31 further conveys the paper and acquires the result that the paper detection unit 37 detects that the paper is located downstream of the second conveyance roller 34b in the paper conveyance direction (step A6). In other words, the third control unit 31 determines that the paper is being held by the second conveyance roller 34b. In step A6, the third control unit 31 may determine that the paper is clamped by the second transport roller 34b based on the length of the paper transported by the first transport roller 34a (the amount of paper feed), without using the detection result of the paper detection unit 37.

[0064] Next, the third control unit 31 causes the first transport roller 34a and the second transport roller 34b to transport the paper S by the post-detection transport distance calculated in step A4. That is, the third control unit 31 transports the paper S until the first line P1 of the patch P reaches the reading position of the image reading unit 32. Thereafter, the third control unit 31 stops the transport of the paper by the first transport roller 34a (step A7).

[0065] Next, the third control unit 31 stops the transport of the paper by the second transport roller 34b a predetermined time after the first transport roller 34a stops the transport of the paper in step A7 (step A8). That is, when switching from a transport state in which the first transport roller 34a and the second transport roller 34b cooperate to transport the same paper to a state in which paper transport is stopped, the third control unit 31 stops the second transport roller 34b after stopping the first transport roller 34a. The third control unit 31 controls the predetermined time by adjusting the number of steps of the stepping motor that is the drive source for the first transport roller 34a and the second transport roller 34b, the transport distance caused by the stepping motor, and the like. The third control unit 31 determines the predetermined time based on the type of paper, the basis weight of the paper, the size of the paper, the position of the patch P in the paper transport direction, the reading position of the image reading unit 32, etc. For example, if the paper is thick paper that is less likely to wrinkle or ripple, the third control unit 31 shortens the predetermined time compared to when the paper is of normal thickness. If the paper is thin paper, rough paper, or other paper with a rough surface, the third control unit 31 lengthens the predetermined time compared to when the paper is normal paper.

[0066] In this way, by stopping the transport of the paper by the second transport roller 34b a predetermined time after the first transport roller 34a stops transporting the paper, the sagging of the paper between the first transport roller 34a and the second transport roller 34b can be eliminated and appropriate tension can be applied to the paper. By stopping the transport of paper by the second transport roller 34b a predetermined time after the first transport roller 34a stops transporting the paper, appropriate tension can be applied to the paper with simpler control than when tension is applied to the paper by the difference between the transport speed of the first transport roller 34a and the transport speed of the second transport roller 34b.

[0067] As described above, the paper conveying force of the second conveyance roller 34b is smaller than that of the first conveyance roller 34a. Therefore, even when the paper conveyance by the second conveyance roller 34b is stopped a predetermined time after the paper conveyance by the first conveyance roller 34a is stopped, the difference between the position of the patch P to be read and the reading position of the image reading unit 32 can be reduced.

[0068] In steps A7 and A8, the third control unit 31 may execute the following process. Specifically, the third control unit 31 transports the paper by the post-detection transport distance using the first transport roller 34a. The third control unit 31 transports the paper by the second transport roller 34b a distance longer than the post-detection transport distance by a distance corresponding to the tension applied to the paper. Alternatively, the third control unit 31 transports the paper by the second transport roller 34b a distance shorter than the post-detection transport distance by the first transport roller 34a a distance corresponding to the tension applied to the paper. Alternatively, the third control unit 31 may determine the distance the first transport roller 34a and the second transport roller 34b transport the paper after the paper detection unit 37 detects the paper, depending on the type, basis weight, size, etc. of the paper.

[0069] Next, the third control unit 31 acquires the result of detection of the position of the paper S in the paper width direction by the edge detection unit 36. Next, the third control unit 31 acquires the position of the chart image formed on the paper S in the paper width direction based on the detection result of the position of the paper S in the paper width direction (step A9), and ends the pre-reading process. The third control unit 31 may perform step A9 next to step A5, but it is preferable to perform this step while the first transport roller 34a and the second transport roller 34b are applying appropriate tension to the paper.

[0070] Returning to FIG. 6, the third control unit 31 executes the odd-numbered row reading process shown in FIG. 8 (step S2).

[0071] (Odd line reading process) The third control unit 31 controls the drive unit 33 to move the image reading unit 32 in the paper width direction from the standby position L1. Next, the third control unit 31 moves the image reading unit 32 to a reading start position for the odd-numbered lines of the patch P based on the position of the chart image in the paper width direction acquired in step A9 of the pre-reading process (step B1). In the example shown in FIG. 10B, the third control unit 31 moves the image reading unit 32 to a reading start position P11 of the first line P1 of the patch P. Next, the third control unit 31 controls the pressing unit 352 to raise and press the background member 351 in a direction toward the image reading unit 32 (positive direction of the Z axis) (step B2). As a result, the third control unit 31 causes the pressed background member 351 to abut the paper S against the image reading unit 32.

[0072] Next, the third control unit 31 reads one line of patches P using the image reading unit 32 (step B3). In step B3, the third control unit 31 reads the first patch P in one row of patches P using the image reading unit 32, and then moves the image reading unit 32 to a reading position for the next patch P. The next patch P is a patch P adjacent to the first patch P in the paper width direction. Next, the third control unit 31 reads the next patch P using the image reading unit 32. Thereafter, the third control unit 31 repeats the movement of the image reading unit 32 in the paper width direction and the reading of the patch P by the image reading unit 32 until one line of patches P has been read. The third control unit 31 controls the movement distance of the image reading unit 32 by adjusting the number of steps of the stepping motor, which is the driving source of the drive unit 33, the movement distance caused by the stepping motor, etc., when the image reading unit 32 moves to the reading position of the adjacent patch P in the paper width direction. As described above, the image reading unit 32 moves in the width direction of the paper while the paper is stopped during transport and reads the chart image, which is image information on the paper. In step B3, the image reading unit 32 moves in the paper width direction while sandwiching the paper S between itself and the background member 351 pressed by the pressing unit 352.

[0073] In step B3, when moving the image reading unit 32 in the paper width direction, the third control unit 31 may cause the pressing unit 352 to press the background member 351 against the image reading unit 32 with a smaller pressure than when the image reading unit 32 reads the patch P. This makes it possible to prevent the occurrence of wrinkles, waves, etc. in the paper due to the movement of the image reading unit 32. Furthermore, this process takes less time than a process in which the background member 351 is lowered and retracted from the paper transport path, and it is possible to stabilize the attitude and position of the paper.

[0074] In steps B2 and B3, the third control unit 31 may execute the following process. Specifically, the third control unit 31 determines whether or not to press the background member 351 with the pressing unit 352 to bring the paper S into contact with the image reading unit 32, based on the type, thickness, basis weight, etc. of the paper. For example, if the paper is one that would develop wrinkles, waves, etc. as the image reading unit 32 moves in the paper width direction, the third control unit 31 moves the image reading unit 32 in the paper width direction and reads the patch P with the image reading unit 32, without pressing the background member 351 with the pressing unit 352. In other words, based on the type and / or basis weight of the paper, the third control unit 31 determines whether, when moving the image reading unit 32 in the paper width direction, the paper should be sandwiched between the background member 351 pressed by the pressing unit 352 and the image reading unit 32, or whether the background member 351 should not be pressed by the pressing unit 352.

[0075] Next, the third control unit 31 controls the pressing unit 352 to lower the background member 351, thereby retracting the background member 351 from the paper transport path (step B4). Next, the third control unit 31 determines whether the line of the patch P read in step B3 is the last line to be read on the paper (last line to be read) (step B5). If the line of patch P read in step B3 is not the last line to be read on the paper (step B5; NO), the third control unit 31 controls the drive unit 33 to move the image reading unit 32 to the retracted position L2 (step B6), as shown in Figure 10C.

[0076] 10D, the third control unit 31 causes the first transport roller 34a and the second transport roller 34b to transport the paper by the distance of one row of patches P. Next, after transporting the paper by the distance of one row of patches P, the third control unit 31 stops transport of the paper by the first transport roller 34a (step B7). Next, the third control unit 31 stops the transport of the paper by the second transport roller 34b (step B8) after a predetermined time has passed since the first transport roller 34a stopped transport of the paper in step B7, and ends the odd-numbered line reading process. The third control unit 31 controls the predetermined time by adjusting the number of steps of the stepping motor that is the drive source for the first transport roller 34a and the second transport roller 34b, the transport distance caused by the stepping motor, and the like.

[0077] On the other hand, if the line of patch P read in step B3 is the last line to be read on the paper (step B5; YES), the third control unit 31 ends the odd-numbered line reading process.

[0078] Returning to FIG. 6, the third control unit 31 determines whether or not reading of the chart image in the odd-numbered line reading process is complete, that is, whether or not the final line of the paper has been read in the odd-numbered line reading process (step S3). If reading of the chart image is not completed in the odd-numbered line reading process (step S3; NO), the third control unit 31 executes the even-numbered line reading process shown in FIG. 9 (step S4).

[0079] (Even line reading process) The third control unit 31 controls the drive unit 33 to move the image reading unit 32 in the paper width direction from the retracted position L2. Next, the third control unit 31 moves the image reading unit 32 to a reading start position for the even-numbered line of the patch P based on the position of the chart image in the paper width direction acquired in step A9 of the pre-reading process (step C1). In the example shown in FIG. 10E, the third control unit 31 moves the image reading unit 32 to the reading start position P21 of the second row P2 of the patch P. Next, the third control unit 31 executes steps C2 to C5 which are similar to steps B2 to B5. If the line of patch P read in step C3 is not the last line to be read on the paper (step C5; NO), the third control unit 31 controls the drive unit 33 to move the image reading unit 32 to the standby position L1 (step C6). Next, the third control unit 31 executes steps C7 and C8 similar to steps B7 and B8, and ends the even-numbered row reading process.

[0080] On the other hand, if the line of patch P read in step C3 is the last line to be read on the paper (step C5; YES), the third control unit 31 ends the even-numbered line reading process.

[0081] Returning to FIG. 6, the third control unit 31 determines whether or not reading of the chart image in the even-numbered line reading process is complete, that is, whether or not the final line of the paper has been read in the even-numbered line reading process (step S5). If reading of the chart image is not completed in the even-numbered line reading process (step S5; NO), the third control unit 31 shifts the image reading process to step S2 and continues reading of the chart image.

[0082] On the other hand, when reading of the chart image is completed in the odd-numbered line reading process (step S3; YES), or when reading of the chart image is completed in the even-numbered line reading process (step S5; YES), the third control unit 31 determines whether the last line read on the paper is an odd-numbered line (step S6). If the last line to be read on the paper is an odd-numbered line (step S6; YES), the third control unit 31 controls the drive unit 33 to move the image reading unit 32 from the reading position of the last patch P of the last line to be read Pe to the retreat position L2 (step S7), as shown in FIG. 10F. Next, the third control unit 31 conveys the sheet S by the conveying unit 34 including the first conveying roller 34a and the second conveying roller 34b, thereby discharging the sheet S to the post-processing device 40 (step S8). Next, the third control unit 31 controls the drive unit 33 to move the image reading unit 32 from the retracted position L2 to the standby position L1 (step S9), and the image reading process ends.

[0083] On the other hand, if the last line to be read on the paper is an even-numbered line (step S6; NO), the third control unit 31 controls the drive unit 33 to move the image reading unit 32 from the reading position of the last patch P of the last line to the standby position L1 (step S10). Next, the third control unit 31 conveys the paper S using the conveying unit 34 including the first conveying roller 34a and the second conveying roller 34b, thereby discharging the paper S to the post-processing device 40 (step S11), and the image reading process ends.

[0084] [effect] As described above, the image reading device 30 of this embodiment is an image reading device that reads image information from a sheet (paper sheet S) after an image has been formed thereon. The image reading device 30 is movable in a sheet width direction (paper width direction) perpendicular to the sheet conveyance direction (paper conveyance direction), and includes an image reading unit 32 that reads image information on the sheet. The image reading device 30 is provided upstream of the image reading unit 32 in the sheet conveying direction, and includes a first conveying means (first conveying roller 34a) for conveying the sheet. The image reading device 30 is provided downstream of the image reading unit 32 in the sheet conveying direction, and includes a second conveying means (second conveying roller 34b) for conveying the sheet. The image reading device 30 is equipped with a control unit (third control unit 31) that stops the second conveying means after stopping the first conveying means when switching from a conveying state in which the first conveying means and the second conveying means cooperate to convey the same sheet to a stopped state in conveying the sheet. Therefore, it is possible to eliminate sagging of the paper between the first transport roller 34a and the second transport roller 34b and apply appropriate tension to the paper, thereby stabilizing the position of the paper relative to the image reading unit 32. This improves the reading accuracy of the image reading unit 32, which moves in the width direction of the paper.

[0085] In the image reading device 30 of this embodiment, the image reading unit 32 moves in the sheet width direction (paper width direction) when the sheet (paper S) is stopped during conveyance to read the image information of the sheet. Therefore, the image reading unit 32 can read image information from the stopped paper, and therefore can read image information with high accuracy.

[0086] In the image reading device 30 of this embodiment, the control unit (third control unit 31) determines the time from when the first conveying means (first conveying roller 34a) is stopped to when the second conveying means (second conveying roller 34b) is stopped based on the type and / or basis weight of the sheet (paper S). Therefore, the above-mentioned time can be set appropriately depending on the type and / or basis weight of the paper.

[0087] The image reading device 30 of this embodiment includes a pressing unit 352 that presses a background member 351 provided at a position opposite the image reading unit 32 toward the image reading unit 32. The image reading unit 32 moves in the sheet width direction (paper width direction) in a state where the sheet (paper S) is sandwiched between the image reading unit 32 and the background member 351 pressed by the pressing unit 352. Therefore, the posture and position of the paper can be stabilized when the image reading unit 32 moves in the paper width direction.

[0088] In the image reading device 30 of this embodiment, the control unit (third control unit 31) determines, based on the type and / or basis weight of the sheet (paper S), whether to sandwich the sheet between the background member 351 pressed by the pressing unit 352 and the image reading unit 32 when moving the image reading unit 32 in the sheet width direction, or whether to not press the background member 351 by the pressing unit 352. Therefore, in the case of paper that is prone to wrinkles, ripples, etc. when the image reading unit 32 is moved in the paper width direction while sandwiched between the background member 351 pressed by the pressing unit 352 and the image reading unit 32, wrinkles, ripples, etc. can be prevented from occurring on the paper by not pressing the background member 351.

[0089] In the image reading device 30 of this embodiment, the image reading unit 32 includes a reducing portion (guide plate 321, rollers 322) at a portion that contacts the sheet (paper S) to reduce the sliding resistance during movement in the sheet width direction (paper width direction). Therefore, by smoothly moving the image reading unit 32 over the paper, the occurrence of paper jams due to the movement of the image reading unit 32 is reduced.

[0090] In the image reading device 30 of this embodiment, the control unit (third control unit 31) reduces the sliding resistance when the image reading unit 32 moves in the sheet width direction (paper width direction) by making the pressing force of the pressing unit 352 smaller than the pressing force when the image reading unit 32 reads the image information of the sheet. This makes it possible to prevent the occurrence of wrinkles, waves, etc. in the paper due to the movement of the image reading unit 32. Furthermore, the processing time is shorter than the process of lowering the background member 351 and retracting it from the paper transport path, and the posture and position of the paper can be stabilized.

[0091] In the image reading device 30 of this embodiment, the first transport means (first transport roller 34a) corrects the skew of the sheet (paper S). Therefore, even if the patch P of the chart image is relatively small, the accuracy of paper transport can be improved by correcting the inclination of the paper using the first transport roller 34a, thereby suppressing errors in reading the patch P by the image reading unit 32.

[0092] In the image reading device 30 of this embodiment, the conveying force of the first conveying means (first conveying roller 34a) is greater than the conveying force of the second conveying means (second conveying roller 34b). Therefore, even if the paper transport by the second transport roller 34b is stopped a predetermined time after the paper transport by the first transport roller 34a is stopped, the difference between the position of the patch P to be read and the reading position of the image reading unit 32 can be reduced.

[0093] In the image reading device 30 of this embodiment, the image reading unit 32 includes a spectrophotometer. This allows for more accurate color measurement than a color scanner.

[0094] The image forming system 1 of this embodiment includes an image forming device 20 that forms an image on a sheet (paper S), and an image reading device 30 that is disposed downstream of the image forming device 20 in the sheet conveying direction. The image forming device 20 forms an adjustment image (chart image) that is two-dimensionally arranged as image information on a sheet. Therefore, it is possible to improve the reading accuracy of the image reading unit 32 that moves in the paper width direction to read the two-dimensionally arranged adjustment images.

[0095] The description of the above embodiment is an example of the image reading device and image forming system according to the present invention, and the present invention is not limited to this. For example, in the above embodiment, the image reading device 30 includes one image reading unit 32. However, the present invention is not limited to this. The image reading device 30 may include a plurality of image reading units 32.

[0096] It goes without saying that the detailed configurations and operations of the components of the image reading device 30 and the image forming system 1 in the above embodiment can be modified as appropriate without departing from the spirit of the present invention. [Explanation of symbols]

[0097] 1. Image forming system 10 Paper feeder 11 First Control Section 12 Conveyor 13 Paper feed section 20 Image forming device 21 Control section 22 Display section 23 Document image reading unit 24 Image forming unit 25 Second Control Section 26 Memory section 27 Communications Department 28 Image processing section 30 Image reader 31 Third Control Section 32 Image reading unit 32a Reading unit 321 Guide Plate 322 Coro 33 Drive unit 34 Conveying section 34a First conveying roller (first conveying means) 34b Second conveying roller (second conveying means) 35 Backing section 351 Background material 352 Pressing part 36 Edge detection unit 37 Paper detection unit 40 Aftertreatment device 41 4th Control Section 42 Post-processing section 43 Conveyor L1 standby position L2 evacuation position P patch R Paper feed range S paper

Claims

1. An image reading device that reads image information on a sheet after an image is formed, an image reading unit that is movable in a sheet width direction perpendicular to a sheet conveying direction and that reads image information of the sheet; a first conveying unit that is provided upstream of the image reading unit in the sheet conveying direction and that conveys the sheet; a second conveying unit provided downstream of the image reading unit in the sheet conveying direction and configured to convey the sheet; a control unit that stops the second conveying means after stopping the first conveying means when switching from a conveying state in which the first conveying means and the second conveying means cooperate to convey the same sheet to a stopped state in conveying the sheet; An image reading device comprising:

2. The image reading device according to claim 1 , wherein the image reading unit, in the stopped state, moves in the sheet width direction to read the image information.

3. The image reading device according to claim 1 , wherein the control unit determines the time from when the first conveying means is stopped until when the second conveying means is stopped based on the type and / or basis weight of the sheet.

4. a pressing unit that presses a background member provided at a position facing the image reading unit toward the image reading unit; The image reading device according to claim 1 , wherein the image reading unit moves in the sheet width direction while sandwiching the sheet between the image reading unit and the background member pressed by the pressing unit.

5. 5. The image reading device according to claim 4, wherein the control unit determines, based on the type and / or basis weight of the sheet, whether to sandwich the sheet between the background member pressed by the pressing unit and the image reading unit when moving the image reading unit in the sheet width direction, or whether to not press the background member with the pressing unit.

6. The image reading device according to claim 1 , wherein the image reading unit includes a reducing portion at a portion that contacts the sheet, the reducing portion reducing a sliding resistance when the sheet moves in the width direction.

7. 5. The image reading device according to claim 4, wherein the control unit reduces the sliding resistance of the image reading unit when it moves in the sheet width direction by making the pressing force of the pressing unit smaller than the pressing force when the image reading unit reads the image information.

8. 2. The image reading device according to claim 1, wherein the first conveying means corrects a skew of the sheet.

9. 2. The image reading device according to claim 1, wherein the conveying force of said first conveying means is greater than the conveying force of said second conveying means.

10. The image reading device according to claim 1 , wherein the image reading unit includes a spectrophotometer.

11. an image forming device for forming an image on the sheet; the image reading device according to claim 1 , which is disposed downstream of the image forming device in the sheet conveying direction; An image forming system comprising:

12. The image forming system according to claim 11 , wherein the image forming device forms, on the sheet, an adjustment image that is two-dimensionally arranged as the image information.

13. An image reading device that reads image information on a sheet after an image is formed, an image reading unit that is movable in a sheet width direction perpendicular to a sheet conveying direction and that reads image information of the sheet; a first conveying unit that is provided upstream of the image reading unit in the sheet conveying direction and that conveys the sheet; a second conveying unit provided downstream of the image reading unit in the sheet conveying direction and configured to convey the sheet; A computer of an image reading device comprising: A program that functions as a control unit that stops the second conveying means after stopping the first conveying means when switching from a conveying state in which the first conveying means and the second conveying means cooperate to convey the same sheet to a stopped state in conveying the sheet.

Images