Image reader and image formation system

Abstract

To provide an image reader and image formation system capable of suppressing colorimetry accuracy deterioration of a colorimeter.SOLUTION: An image formation system 1 comprises an image reader 30 comprising a conveyance unit 34 comprising a plurality of conveyance paths for conveying a storage medium on which an image is formed, a reading unit 32 for reading the image, and a colorimetry unit 33 comprising a colorimeter C for performing colorimetry of the image. The conveyance unit 34 comprises a first conveyance path 35, a second conveyance path 36, and a third conveyance path 37 on a downstream side of the reading unit 32 in a conveyance direction. Path lengths of the second conveyance path 36 and the third conveyance path 37 are longer than a path length of the first conveyance path 35. The colorimetry unit 33 is provided on the second conveyance path 36 or the third conveyance path 37.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an image reading apparatus and an image forming system.

Background Art

[0002] Conventionally, an image reading apparatus is known that includes a conveyance path for conveying a recording medium on which an image is formed by an image forming apparatus, a scanner for reading the image, and a colorimeter for measuring the color of the image.

[0003] In an image reading apparatus, it takes a predetermined time to inspect and determine the quality of the read image or to determine the image quality or the like. Therefore, a configuration is known in which a detour path for securing the predetermined time during paper conveyance is provided on the downstream side in the conveyance direction of the scanner and the colorimeter. However, providing a detour path on the downstream side of the scanner and the colorimeter has a problem that the length in the conveyance direction from the scanner to the exit (lateral direction toward the front of the image reading apparatus) becomes long, and the size in the conveyance direction increases.

[0004] Therefore, for example, Patent Document 1 describes an image reading apparatus in which a detour path that detours a part of the paper conveyance path is provided on the downstream side of the scanner, and a colorimeter is provided in the detour path. With such an image reading apparatus, the length in the conveyance direction from the scanner to the exit can be shortened and the apparatus can be miniaturized.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, in the invention of Patent Document 1, even when only a scanner is used, it is necessary to convey the recording medium through a detour path provided with a colorimeter. Then, due to the passage of the recording medium that does not require color measurement through the detour path, the wear of the rollers arranged upstream and downstream of the colorimeter may be accelerated, the colorimeter may be damaged, or foreign matter may adhere, which may reduce the color measurement accuracy of the colorimeter. Generally, a high color measurement accuracy is required for the colorimeter, so the allowable range for the depth of field is narrow. In addition, since the influence of scratches and foreign matter adhesion is also large, it is desirable not to pass the paper through the position of the colorimeter as much as possible when color measurement is not required.

[0007] The present invention has been made in view of such circumstances. Its object is to provide an image reading apparatus and an image forming system capable of suppressing a decrease in the color measurement accuracy of a colorimeter.

Means for Solving the Problems

[0008] In order to solve the above problems, the invention according to claim 1 is an image reading apparatus, comprising: a conveyance unit including a plurality of conveyance paths for conveying a recording medium on which an image is formed; a reading unit for reading the image; a color measurement unit including a colorimeter for measuring the color of the image, the conveyance unit includes a first conveyance path, a second conveyance path, and a third conveyance path on the downstream side in the conveyance direction from the reading unit, and the path lengths of the second conveyance path and the third conveyance path are longer than the path length of the first conveyance path; the color measurement unit is provided in the second conveyance path or the third conveyance path.

[0009] The invention according to claim 2 is the image reading apparatus according to claim 1, the second conveyance path and the third conveyance path branch from the first conveyance path and merge into the first conveyance path on the downstream side in the conveyance direction from the branch portion with the first conveyance path.

[0010] The invention according to claim 3 is the image reading apparatus according to claim 2, the third conveyance path branches from the second conveyance path.

[0011] The invention according to claim 4 is the image reading apparatus according to claim 3, wherein the first conveyance path is formed linearly from an inlet portion toward an outlet portion; the second conveyance path is provided so as to detour downward in the vertical direction with respect to the first conveyance path; the third conveyance path is provided so as to detour downward in the vertical direction with respect to the second conveyance path.

[0012] The invention according to claim 5 is the image reading apparatus according to claim 2 or 3, wherein the first conveyance path is formed linearly from an inlet portion toward an outlet portion; the second conveyance path is provided so as to detour downward in the vertical direction with respect to the first conveyance path; the third conveyance path is provided so as to detour downward in the vertical direction on the downstream side of the second conveyance path with respect to the first conveyance path.

[0013] The invention according to claim 6 is the image reading apparatus according to any one of claims 1 to 4, comprising a control unit configured to control the conveyance unit so that a recording medium to be color-measured by the colorimeter is conveyed through a conveyance path provided with the color measurement unit among the second conveyance path and the third conveyance path, and a recording medium that is not a color measurement target by the colorimeter is conveyed through a conveyance path not provided with the color measurement unit among the first conveyance path to the third conveyance path.

[0014] The invention according to claim 7 is the image reading apparatus according to claim 6, comprising a control unit configured to control the conveyance unit so that a recording medium that is not a reading target by the reading unit and is not a color measurement target by the colorimeter is conveyed through the first conveyance path.

[0015] The invention according to claim 8 is the image reading apparatus according to any one of claims 1 to 4, The reading unit includes a first scanner that reads an image on the first surface of the recording medium, and a second scanner that reads an image on the second surface of the recording medium facing the first surface of the recording medium.

[0016] The invention according to claim 9 is the image reading apparatus according to claim 6, wherein The control unit controls the conveyance unit to convey a recording medium that is a reading target by the reading unit and not a color measurement target by the colorimeter through a conveyance path in which the color measurement unit is not provided among the second conveyance path and the third conveyance path.

[0017] The invention according to claim 10 is an image forming system, comprising An image forming apparatus that forms an image on a recording medium, and The image reading apparatus according to any one of claims 1 to 4 that conveys the recording medium on which an image is formed by the image forming apparatus.

Advantages of the Invention

[0018] According to the present invention, it is possible to suppress a decrease in the color measurement accuracy of the colorimeter.

Brief Description of the Drawings

[0019]

Figure 1

Figure 2

Figure 3

Figure 4A

Figure 4B

Figure 4C

Modes for Carrying Out the Invention

[0020] Hereinafter, an image forming system including an image reading apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings. However, the scope of the invention is not limited to the illustrated examples. In the following description, components having the same functions and configurations are denoted by the same reference numerals, and the description thereof will be omitted.

[0021] [Overall Configuration of Image Forming System] [First Embodiment] FIG. 1 is a side sectional view showing the main configuration of an image forming system 1 according to the first embodiment of the present invention. FIG. 2 is a block diagram showing the functional configuration of the image forming system 1.

[0022] Hereinafter, in the following description, the X direction, Y direction, and Z direction refer to the directions shown in FIG. 1. Further, in the following description, the X direction, Y direction, and Z direction will be described as the width direction, conveyance direction, and height direction, respectively.

[0023] As shown in FIG. 1, the image forming system 1 includes a paper feeding device 10, an image forming device 20, and an image reading device 30. The paper feeding device 10, the image forming device 20, and the image reading device 30 are arranged in order toward the downstream side in the conveyance direction of the recording medium. Also, the paper conveyance paths of the paper feeding device 10, the image forming device 20, and the image reading device 30 are connected. Therefore, the recording medium is continuously conveyed from the paper feeding device 10 through the image forming device 20 to the image reading device 30.

[0024] [Paper Feeding Device] The paper feeding device 10 is a device that supplies the stored recording medium to the image forming device 20. The paper feeding device 10 includes a control unit 11, a conveyance unit 12, and a paper feeding unit 13.

[0025] [Control Unit] The control unit 11 includes a CPU (Central Processing Unit) 111, a ROM (Read Only Memory) 112, and a RAM (Random Access Memory) 113. The CPU 111 reads out the program stored in the ROM 112 and expands it in the RAM 113. The CPU 111 comprehensively controls each part of the paper feeding device 10 according to the expanded program. For example, the control unit 11 conveys a recording medium from any of the paper feed trays 131 to 133 of the paper feed unit 13 to the image forming apparatus 20 according to a job.

[0026] {Transport unit, paper feed unit} The transport unit 12 includes a transport path 121 and transport rollers (not shown). The transport path 121 connects from the paper feed unit 13 to the image forming apparatus 20. The transport rollers convey the recording medium in the transport path 121. The paper feed unit 13 has paper feed trays 131 to 133 for storing recording media for each predetermined paper type and size.

[0027] Note that a detection device for detecting the physical properties of the recording medium may be provided between the paper feeding device 10 and the image forming apparatus 20.

[0028] (Image forming apparatus) The image forming apparatus 20 is located on the downstream side in the transport direction of the paper feeding device 10 and on the upstream side of the image reading device 30. The image forming apparatus 20 acquires image data by reading an image from a document or by receiving it from an external device (not shown). The image forming apparatus 20 forms an image based on the acquired image data. After image formation, the image forming apparatus 20 conveys the recording medium to the image reading device 30.

[0029] The image forming apparatus 20 includes an operation unit 21, a display unit 22, a document reading unit 23, an image forming unit 24, a control unit 25, a storage unit 26, a communication unit 27, and an image processing unit 28.

[0030] {Operation unit} The operation unit 21 includes, for example, a touch panel formed to cover the display screen of the display unit 22, and various operation buttons such as numeric buttons and a start button. The operation unit 21 outputs an operation signal based on a user's operation to the control unit 25.

[0031] {Display unit} The display unit 22 includes an LCD (Liquid Crystal Display) or the like. The display unit 22 displays various screens according to an instruction of a display signal input from the control unit 25.

[0032] {Original document reading unit} The original document reading unit 23 includes an automatic document feeder (ADF) and a scanner or the like. The original document reading unit 23 outputs image data obtained by reading an image of an original document to the control unit 25.

[0033] {Image forming unit} The image forming unit 24 forms an image on a recording medium conveyed from the paper feeding device 10 based on the acquired image data. In this embodiment, the recording medium is a single sheet of paper. 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.

[0034] 〔Photosensitive drum〕 The photosensitive drums include those individually corresponding to each color of, for example, yellow (Y), magenta (M), cyan (C), black (K), and special color (S). In this embodiment, the special color is exemplified by white. That is, the photosensitive drums include photosensitive drums 241Y, 241M, 241C, 241K, and 241S.

[0035] The image forming unit 24 uniformly charges the photosensitive drum 241Y and then 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 attaches yellow toner to the electrostatic latent image on the photosensitive drum 241Y to perform development. Since the photosensitive drums 241M to 241S form images in the same manner as the photosensitive drum 241Y except for the different colors to be handled, the description thereof is omitted.

[0036] [Intermediate Transfer Belt] The image forming unit 24 transfers the toner images of respective colors formed on the photoreceptor drums 241Y to 241S onto the intermediate transfer belt 242. The transfer onto the intermediate transfer belt 242 is the primary transfer. That is, the image forming unit 24 forms a color toner image in which five-color toner images are superimposed on the intermediate transfer belt 242.

[0037] [Secondary Transfer Roller] The image forming unit 24 collectively transfers the color toner image on the intermediate transfer belt 242 onto the recording medium by the secondary transfer roller 243. The transfer onto the recording medium is the secondary transfer. Further, the nip portion formed by the intermediate transfer belt 242 and the secondary transfer roller 243 is the transfer portion.

[0038] [Fixing Unit] The fixing unit 244 includes a heating roller and a pressure roller. The heating roller heats the recording medium onto which the color toner image is transferred. The pressure roller pressurizes the recording medium heated by the heating roller. By the heating and pressurization of the fixing unit 244, the color toner image is fixed on the recording medium.

[0039] [Control Unit] The control unit 25 includes a CPU 251, a ROM 252, and a RAM 253. The CPU 251 reads out various processing programs stored in the ROM 252 and expands them in the RAM 253. The control unit 25 comprehensively controls the operation of the image forming apparatus 20 in cooperation with the various programs expanded in the RAM 253.

[0040] [Storage Unit] The storage unit 26 stores data such as program data and various setting data in a readable and writable manner from the control unit 25. Further, the storage unit 26 stores the paper feed trays 131 to 133 in association with information such as the basis weight, size, and paper type of the recording medium stored therein. The storage unit 26 is a non-volatile storage device such as an HDD (Hard Disk Drive) or a semiconductor memory that stores various data such as programs and image data.

[0041] {Communication unit} The communication unit 27 performs transmission and reception of various data with an external device such as a personal computer connected to a communication network such as a LAN (Local Area Network) or a WAN (Wide Area Network). The communication unit 27 includes a communication control card such as a LAN card.

[0042] {Image processing unit} The image processing unit 28 performs necessary image processing on the image data before image formation. The image data includes that stored in the storage unit 26, that obtained by reading a document by the document reading unit 23, and that input from an external device.

[0043] Then, the image processing unit 28 transmits the image data after image processing to the image forming unit 24. The image processing includes tone processing, halftone processing, color conversion processing, etc. Tone processing is a process of converting the tone value of each pixel of the image data into a tone value corrected so that the density characteristic of the image formed on the recording medium matches the target density characteristic. Halftone processing is error diffusion processing, screening processing using an ordered dither method, etc. Color conversion processing is a process of converting each tone value of RGB into each tone value of CMYK. Note that the processing of the above-described image processing unit 28 may be realized by a program executed by the CPU of the control unit 25.

[0044] (Image reading device) The image reading device 30 is arranged on the downstream side in the conveyance direction of the image forming device 20. The image reading device 30 includes a control unit 31, a reading unit 32, a color measurement unit 33, a conveyance unit 34, and a paper discharge tray 38. The image reading device 30 reads a recording medium conveyed from the image forming device 20 and acquires image data (read image data).

[0045] {Control Unit} The control unit 31 includes a CPU 311, a ROM 312, and a RAM 313. The CPU 311 reads out various processing programs stored in the ROM 312 and expands them in the RAM 313. The control unit 31 comprehensively controls the operation of the image forming device 20 in cooperation with the various programs expanded in the RAM 313.

[0046] {Reading Unit} The reading unit 32 is provided on the upstream side in the conveyance direction from the branch position between the second conveyance path 36 and the third conveyance path 37 in the first conveyance path 35 of the conveyance unit 34 described later. Also, the reading unit 32 is arranged on the downstream side in the conveyance direction from the image forming unit 24. Therefore, the reading unit 32 can read an image while the recording medium is being conveyed.

[0047] In the present embodiment, as shown in FIG. 1, the reading unit 32 includes individual color scanners on both sides sandwiching the recording medium conveyed in the first conveyance path 35. One scanner, the first scanner SC1, reads an image on the first surface of the recording medium, for example, the upper surface. The other scanner, the second scanner SC2, reads an image on the second surface facing the first surface of the recording medium, for example, the lower surface.

[0048] The reading unit 32 acquires read image data by reading the image formed on the recording medium by the image forming unit 24. Then, the reading unit 32 outputs the acquired read image data to the image processing unit 28. The image processing unit 28 analyzes not only the image processing for the image data before image formation but also the read image data of the reading unit 32.

[0049] Specifically, the image processing unit 28 calculates, from the read image data, the amount of positional deviation of the images formed on the front and back sides of the recording medium with respect to the recording medium, a positional deviation adjustment value, an image color adjustment value, etc. Furthermore, the image processing unit 28 detects defects in the image formed on the recording medium from the read image data. The image processing unit 28 outputs the analysis results of the read image data to the control unit 25 of the image forming apparatus 20. Furthermore, the control unit 31 performs various calibrations based on the read image data read by the reading unit 32.

[0050] {Color measurement section} The colorimeter 33 is provided in a parallel portion (horizontal portion 36b of the second conveying path 36 in this embodiment) of either the second conveying path 36 or the third conveying path 37 described later. The colorimeter 33 is composed of a spectrophotometer C and a drive unit (not shown) that scans the spectrophotometer C in the width direction. The colorimeter 33 scans the spectrophotometer C in the width direction by the drive unit, thereby measuring the color of a chart image recorded on a recording medium conveyed on the second conveying path 36 or the third conveying path 37. The colorimeter 33 also outputs the colorimeter result of the chart image to the control unit 31. The control unit 31 creates a color profile based on the gradation values ​​measured by the colorimeter 33, and transmits the color profile to the image forming apparatus 20. The control unit 25 corrects the hue by referring to the color profile when the image forming unit 24 forms an image.

[0051] {Transportation section} The transport section 34 has a transport path that connects the image forming device 20 to the paper discharge tray 38, and a plurality of transport rollers that transport the recording medium on the transport path. The transport path includes, for example, a first transport path 35 that connects the image forming device 20 to the paper discharge tray 38. The transport path also includes a second transport path 36 and a third transport path 37 that branch off from the first transport path 35 midway, make a detour downward, and then merge with the first transport path 35 again downstream of the branch.

[0052] [First conveying path] The first conveyance path 35 is a conveyance path used, for example, when normally conveying a recording medium. The first conveyance path 35 is provided so as to connect, in a substantially straight line, from the connection portion with the image forming apparatus 20, which is the entrance portion of the image reading apparatus 30, to the paper discharge tray 38, which is the exit portion. With this configuration, conveyance can be performed over the shortest distance from image formation by the image forming apparatus 20 to paper discharge to the paper discharge tray 38, and the productivity of the image forming system 1 can be further enhanced.

[0053] 〔Second Conveyance Path〕 When the second conveyance path 36 branches off from the first conveyance path 35, it greatly detours downward and then merges into the first conveyance path 35 with its path directed upward. In the present embodiment, the second conveyance path 36 includes an inclined portion 36a and a horizontal portion 36b. The inclined portion 36a is provided between the branching point with the first conveyance path 35 and the horizontal portion 36b in the second conveyance path 36, and is a linear portion formed to be inclined downward. The horizontal portion 36b is provided at the lower end portion of the second conveyance path 36 and is a linear portion formed parallel to the horizontal direction. Note that the path length of the second conveyance path 36 is longer than the path length of the first conveyance path 35.

[0054] 〔Third Conveyance Path〕 When the third conveyance path 37 branches off from the second conveyance path 36, it greatly detours further downward than the second conveyance path 36 and then merges into the second conveyance path 36 with its path directed upward. Thus, in the present embodiment, a part of the third conveyance path 37 also serves as a part of the second conveyance path 36. Therefore, the path length of the third conveyance path 37 is longer than the path lengths of the first conveyance path 35 and the second conveyance path 36.

[0055] At the branching position from the first conveyance path 35 to the second conveyance path 36 and the branching position from the second conveyance path 36 to the third conveyance path 37, a branching guide G capable of changing the path of the recording medium is arranged. The branching guide G can change its orientation by an actuator controlled by the control unit 31. The control unit 31 can appropriately switch the conveyance path of the recording medium between the second conveyance path 36 and the third conveyance path 37 by changing the orientation of the branching guide G.

[0056] Note that the first conveyance path 35, the second conveyance path 36, and the third conveyance path 37 may each be constituted by guides or wall portions for guiding a recording medium along the conveyance path. Further, the first conveyance path 35, the second conveyance path 36, and the third conveyance path 37 may each be constituted by a plurality of guide rollers arranged side by side along their respective paths.

[0057] {Paper discharge tray} The paper discharge tray 38 is provided connected to the outlet of the image reading device 30. A plurality of paper discharge trays 38 are provided, and paper is discharged to different locations according to the reading result of the recording medium and the like.

[0058] [Effects of the First Embodiment] FIG. 3 is a table summarizing the conveyance paths for conveying the recording medium in each mode. As shown in FIG. 3, the control unit 31 conveys the recording medium whose image is color-measured by the color measurement unit 33 to the second conveyance path 36 where the color measurement unit 33 is provided. Further, the control unit 31 conveys the recording medium that is automatically inspected by reading the image with the reading unit 32 to the third conveyance path 37 which is a detour path. Then, the control unit 31 conveys the recording medium that is not the object of reading by the reading unit 32 or color measurement by the color measurement unit 33 to the first conveyance path 35. Further, the image reading device 30 of the image forming system according to the present embodiment separately includes the first conveyance path 35, the second conveyance path 36, and the third conveyance path 37 as the conveyance unit 34. Thus, since the image reading device 30 does not use the second conveyance path 36 where the color measurement unit 33 is provided as a detour path after the reading by the reading unit 32, a decrease in the color measurement accuracy of the spectrocolorimeter C can be suppressed.

[0059] Further, according to this configuration, for example, while the first recording medium is being conveyed on the second conveyance path 36, the second recording medium can also be conveyed on the first conveyance path 35 or the third conveyance path 37. When the image is color-measured by the color measurement unit 33, it is necessary to make the speed lower than the conveyance speed of the recording medium when not color-measuring. Therefore, for the second recording medium that is a subsequent recording medium of the first recording medium to be color-measured and does not require color measurement, by conveying it on the first conveyance path 35 or the third conveyance path 37 where the colorimeter is not arranged, the conveyance speed of the subsequent recording medium can be increased. As a result, the productivity of the image forming process can be enhanced.

[0060] In the conveying section 34, the first conveying path 35 is linear from the entrance to the exit. In contrast, the second conveying path 36 is a conveying path that detours downward, and the third conveying path 37 is a conveying path that detours further downward than the second conveying path 36. In addition, the second conveying path 36 and the third conveying path 37 branched off from the first conveying path 35 merge into the first conveying path 35. Therefore, the length of the image reading device 30 in the conveying direction (the horizontal size when viewed from the front of the image reading device 30) can also be reduced.

[0061] [Second embodiment] Next, an image forming system 1A according to a second embodiment will be described with reference to Fig. 4A. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted. As shown in Fig. 4A, the image forming system 1A according to the second embodiment differs from the first embodiment in the configuration of the conveying unit 34 of the image reading device 30A.

[0062] In detail, in the second embodiment, the colorimetric unit 33 is provided in the third transport path 37, not in the second transport path 36. Also, in the second embodiment, the control unit 31 transports the recording medium through the second transport path 36, in which the colorimetric unit 33 is not provided, as a detour route after reading by the reading unit 32.

[0063] [Effects of the second embodiment] The image reading device 30A according to the second embodiment also has a separate transport path (third transport path 37) for transporting the recording medium when the color measurement unit 33 measures the color of an image, and a separate transport path (second transport path 36) for transporting the recording medium after reading by the reading unit 32. Therefore, similar to the first embodiment, it is possible to suppress a decrease in the color measurement accuracy of the spectrophotometer C. In this way, in the image reading device 30 (30A), the color measurement unit 33 can be provided on either the second transport path 36 or the third transport path 37.

[0064] [Third embodiment] Next, the image forming system 1B according to the third embodiment will be described with reference to FIG. 4B. Note that the same components as those in the first and second embodiments are denoted by the same reference numerals, and detailed descriptions thereof are omitted. As shown in FIG. 4B, in the image forming system 1B of the third embodiment, the configuration of the conveyance unit 34 of the image reading device 30B is different from that in the first and second embodiments.

[0065] Specifically, in the third embodiment, a third conveyance path 37B separate from the second conveyance path 36B is provided so as to branch from the first conveyance path 35 on the downstream side of the second conveyance path 36.

[0066] [Effects of the Third Embodiment] In the first and second embodiments, since the third conveyance path branched so as to detour downward from the second conveyance path 36, there was a design constraint that the path length of the third conveyance path was always longer than the path length of the second conveyance path 36. On the other hand, in the third embodiment, since the second conveyance path 36B and the third conveyance path 37B are separate bodies, the path lengths of the second conveyance path 36B and the third conveyance path 37B can be arbitrarily set as appropriate.

[0067] In FIG. 4B, a configuration in which the color measurement unit 33 is provided in the second conveyance path 36B is illustrated, but the present invention is not limited thereto. That is, also in the image reading device 30B according to the third embodiment, the color measurement unit 33 may be provided in the third conveyance path 37B as in the second embodiment.

[0068] [Fourth Embodiment] Next, the image forming system 1C according to the fourth embodiment will be described with reference to FIG. 4C. Note that the same components as those in the first to third embodiments are denoted by the same reference numerals, and detailed descriptions thereof are omitted. As shown in FIG. 4C, in the image forming system 1C of the fourth embodiment, the configuration of the conveyance unit 34 of the image reading device 30C is different from that in the first to third embodiments.

[0069] Specifically, in the fourth embodiment, the third conveyance path 37C branches from a part of the second conveyance path 36C, and the third conveyance path 37C is provided so as to be located on the downstream side of the second conveyance path 36C. A recording medium that does not require color measurement by the color measurement unit 33 merges into the first conveyance path 35 without being sent to the third conveyance path 37C after being conveyed through the second conveyance path 36C. A recording medium that requires color measurement by the color measurement unit 33 is conveyed to the second conveyance path 36C, then sent to the third conveyance path 37C, color-measured via the position of the color measurement unit 33, and then merges into the first conveyance path 35.

[0070] [Effects of the Fourth Embodiment] Also in this configuration, similar to the third embodiment, since the third conveyance path 37C is provided on the downstream side of the second conveyance path 36C, the path lengths of the second conveyance path 36C and the third conveyance path 37C can be arbitrarily set as appropriate. On the other hand, different from the third embodiment, since the third conveyance path 37C branches from a part of the second conveyance path 36C, the number of parts of the conveyance path and the conveyance rollers can be reduced.

[0071] In this configuration, it is preferable to provide the color measurement unit 33 only on the third conveyance path 37C and not on the second conveyance path 36C. This is because if the color measurement unit 33 is provided on the second conveyance path 36C, there is a risk that the recording medium conveyed on the third conveyance path 37C passes below the color measurement unit 33, reducing the color measurement accuracy of the spectroscopic colorimeter C.

[0072] [Other Configurations] As described above, specific explanations have been made based on the embodiments according to the present invention, but the present invention is not limited to the above-described embodiments. Of course, various modifications are possible, including those within the scope of the invention described in the claims and their equivalents.

[0073] For example, in the above, a configuration in which the second conveyance path 36 and the third conveyance path 37 are provided so as to bypass downward with respect to the first conveyance path 35 has been illustrated, but it is not limited to this. That is, the second conveyance path 36 and / or the third conveyance path 37 may be provided so as to bypass, for example, upward with respect to the first conveyance path 35.

[0074] In the above description, an example is given in which the reading unit 32 includes two scanners (first scanner SC1 and second scanner SC2), but the present invention is not limited to this. For example, when the image forming apparatus 20 forms an image only on one side of the recording medium, the image forming apparatus 20 may be configured to include only one scanner.

[0075] In the above description, an example is given in which the image forming apparatus 20 forms an image by an electrophotographic method using toner, but the present invention is not limited to this. The present invention is also applicable when the image forming apparatus 20 is configured to form an image by an inkjet method using ink.

[0076] In the above description, an example is given in which the paper feeding apparatus 10, the image forming apparatus 20, and the image reading apparatus 30 each include control units 11, 25, and 31 and cooperate with each other, but the present invention is not limited to this. That is, the image forming system 1 may be configured to include only one control unit that comprehensively controls the image forming system 1. Further, an apparatus separate from the paper feeding apparatus 10, the image forming apparatus 20, and the image reading apparatus 30 may be configured to include such a control unit.

Explanation of Reference Numerals

[0077] 1 Image forming system 20 Image forming apparatus 30 Image reading apparatus 31 Control unit 32 Reading unit 33 Color measurement unit 34 Conveying unit 35 First conveyance path 36 Second conveyance path 37 Third conveyance path C Spectrophotometer (colorimeter) SC1 First scanner SC2 Second scanner

Claims

1. A conveying unit including a plurality of conveying paths for conveying a recording medium on which an image is formed; A reading unit that reads the image; a color measurement unit including a colorimeter for measuring the color of the image; the transport unit includes a first transport path, a second transport path, and a third transport path downstream of the reading unit in a transport direction, and a path length of the second transport path and the third transport path is longer than a path length of the first transport path; The color measurement unit is an image reading device provided on the second transport path or the third transport path.

2. The image reading device according to claim 1 , wherein the second transport path and the third transport path branch off from the first transport path and merge with the first transport path downstream in the transport direction from a branch point with the first transport path.

3. The image reading apparatus according to claim 2 , wherein the third transport path branches off from the second transport path.

4. The first transport path is formed linearly from the inlet portion to the outlet portion, the second transport path is provided to make a detour downward in the up-down direction with respect to the first transport path, The image reading device according to claim 3 , wherein the third transport path is provided so as to make a detour downward with respect to the second transport path.

5. The first transport path is formed linearly from the inlet portion to the outlet portion, the second transport path is provided to make a detour downward in the up-down direction with respect to the first transport path, 4. The image reading apparatus according to claim 2, wherein the third transport path is provided to make a detour downward in a vertical direction with respect to the first transport path on a downstream side of the second transport path.

6. 5. The image reading device according to claim 1, further comprising a control unit that controls the transport unit so that a recording medium to be measured by the colorimeter is transported along one of the second and third transport paths, in which the colorimeter unit is provided, and a recording medium not to be measured by the colorimeter is transported along one of the first and third transport paths, in which the colorimeter unit is not provided.

7. The image reading device according to claim 6 , wherein the control unit controls the transport unit to transport, via the first transport path, a recording medium that is not a target for reading by the reading unit and is not a target for color measurement by the colorimeter.

8. 5. The image reading device according to claim 1, wherein the reading unit comprises a first scanner that reads an image on a first surface of the recording medium, and a second scanner that reads an image on a second surface opposite the first surface of the recording medium.

9. The image reading apparatus according to claim 6, wherein the control unit causes a recording medium that is a reading target by the reading unit and not a color measurement target by the colorimeter to be conveyed through a conveyance path among the second conveyance path and the third conveyance path where the color measurement unit is not provided.

10. An image forming apparatus that forms an image on a recording medium, and an image reading apparatus according to any one of claims 1 to 4 that conveys the recording medium on which an image is formed by the image forming apparatus. An image forming system comprising the same.

Images