Image reading device and image forming system

Abstract

To prevent increase in a size and increase in the number of components of an image reading device.SOLUTION: An image reading device comprises: a case that has conductivity; a CIS 401 that has a reading sensor reading an image of a sheet to be conveyed and is accommodated in the case; a conductive carriage 418 that supports the CIS 401; and a moving mechanism 460 that supports the carriage 418 movably with respect to the case. The moving mechanism 460 has: a guide shaft 419 that has conductivity and is attached to the case; a bushing 461 that has conductivity and is supported movably in an axial direction with respect to the guide shaft 419; a holder 470 that is formed of a non-conductive material, accommodates the bushing 461, and supports the carriage 418; and a ground plate 480 that has conductivity, is interposed between the carriage 418 and the holder 470, and electrically connects the carriage 418 and the bushing 461 to each other. The carriage 418 and the case are electrically connected with each other.SELECTED DRAWING: Figure 14

Description

[Technical field]

[0001] The present invention relates to an image reading apparatus for reading an image on a sheet, and an image forming system to which the image reading apparatus is applied. [Background technology]

[0002] Conventionally, in an image reading device that reads an image formed on a sheet by an image forming device, a carriage (support member) equipped with a reading sensor is known that slides on a slidably supported guide rod (support shaft) (see Patent Document 1). This image reading device is movable between a reading position where the image is read and a shading position where shading correction is performed to perform uniform reading by the reading sensor used for reading. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2021-158440 A Summary of the Invention [Problem to be solved by the invention]

[0004] In an image reading device using such a carriage, if the carriage that holds the reading sensor is made of metal, it is desirable to electrically ground the carriage so that, for example, noise is not included in the electrical signal. However, if a new dedicated cable is provided to electrically ground the moving carriage in the image reading device described in the above-mentioned Patent Document 1, it is necessary to secure space for the cable to move and a mechanism to hold the cable. This may lead to an increase in the size of the image reading device and an increase in the number of parts.

[0005] An object of the present invention is to provide an image reading device and an image forming system that can suppress an increase in size and number of parts. [Means for solving the problem]

[0006] One aspect of the present invention is an image reading device comprising a conductive case, a reading unit having a reading sensor that reads an image on a transported sheet and is housed in the case, a conductive support member that supports the reading unit, and a moving mechanism that supports the support member so that it can be moved relative to the case, wherein the moving mechanism has a conductive support shaft attached to the case, a conductive moving part that is supported so as to be axially movable relative to the support shaft, a support base made of a non-conductive material that houses the moving part and supports the support member, and a first conductive member that is conductive and is interposed between the support member and the support base, providing electrical conductivity between the support member and the moving part, and is characterized in that the moving mechanism provides electrical conductivity between the support member and the case.

[0007] Another aspect of the present invention is an image forming system comprising an image forming apparatus having an image forming unit that forms an image on a sheet, and the above-mentioned image reading device that reads an image on the sheet on which an image has been formed in the image forming unit. Effect of the Invention

[0008] According to the present invention, it is possible to prevent breakage, wear, and the like of the flat cable. [Brief description of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view showing an image forming system according to an embodiment. [Diagram 2] FIG. 2 is a block diagram showing a control system of the image forming apparatus system according to the embodiment. [Diagram 3] 5A and 5B are cross-sectional views showing an original reading unit according to an embodiment, in which FIG. 5A illustrates a state in which the CIS is located at a reference position, and FIG. 5B illustrates a state in which the CIS is located at a maximum movement position. [Figure 4] FIG. 2 is a cross-sectional view showing an adjustment and inspection unit according to the embodiment. [Diagram 5] FIG. 4 is a cross-sectional view showing an adjustment and inspection unit according to the embodiment. [Figure 6] FIG. 4 is an explanatory diagram showing a paper library screen according to the first embodiment. [Figure 7] 1A and 1B are diagrams showing test patterns according to an embodiment, where FIG. 1A is a test pattern for the front side, and FIG. 1B is a test pattern for the back side. [Figure 8] FIG. 2 is an explanatory diagram illustrating a paper library according to the embodiment. [Figure 9] FIG. 2 is a cross-sectional view showing the loading device according to the embodiment. [Figure 10] 5A and 5B are cross-sectional views showing a first-page reading unit according to an embodiment, in which FIG. 5A shows a state in which the CIS is located at a reading position, and FIG. 5B shows a state in which the CIS is located at a shading position. [Figure 11] FIG. 2 is a front view showing a moving mechanism according to the embodiment. [Figure 12] FIG. 2 is a perspective view showing a moving mechanism according to the embodiment. [Figure 13] FIG. 2 is an exploded perspective view showing a moving mechanism according to the embodiment. [Figure 14] FIG. 4 is a side view showing a moving mechanism according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS. 1 to 14. First, a schematic configuration of an image forming apparatus 1 according to this embodiment will be described with reference to FIG. 1. FIG. 1 is a cross-sectional view of an image forming system 100. The image forming system 100 includes an image forming apparatus 1, an operation unit 180, an adjustment inspection unit 200, and a loading device 601. The image forming apparatus 1 forms an image on a sheet S. The operation unit 180 is operated by a user to set conditions for image formation in the image forming apparatus 1, and also displays the state of the image forming apparatus 1. The adjustment inspection unit 200 performs front-back registration for measuring the positional deviation between an image formed on the front side of the sheet S and an image formed on the back side by the image forming apparatus 1, and performs inspection processing to detect the presence or absence of defects in the image formed on the sheet S. That is, the adjustment inspection unit 200 reads an image of a sheet on which an image is formed in the image forming unit 102 of the image forming apparatus 1. The stacking device 601 is a device that discharges and stacks the sheets S on which images have been formed onto a discharge tray, but other post-processing devices such as stapling, punching, and sorting may also be attached.

[0011] [Image forming device] The image forming apparatus 1 is an electrophotographic laser beam printer. The image forming apparatus 1 forms an image on a sheet S using an electrophotographic image forming process. In this embodiment, a full-color copying machine having a plurality of photosensitive drums is applied. However, the present invention is not limited to this, and the present invention can also be applied to a monochrome or mono-color copying machine or printer having one photosensitive drum. In addition to a laser beam printer, the image forming apparatus 1 can also be applied to, for example, an electrophotographic copying machine (e.g., a digital copying machine), a color LED printer, an MFP (multifunction machine), a facsimile machine, and a printing machine. Furthermore, the present invention is not limited to the electrophotographic system, and can also be applied to an inkjet printer, a dye-sublimation printer, or a thermal printer using a thermal drying method.

[0012] 2 is a block diagram of the image forming apparatus 1 and the adjustment and inspection unit 200. The image forming apparatus 1 has a printer controller 103, an engine control unit 312, and an engine unit 140. The printer controller 103 has a paper library 800 and an image shape correction unit 320. The printer controller 103 is electrically connected to an operation unit 180, the engine control unit 312, a control unit 560 of the document reading unit 190, and a communication unit of a control board 250 of the adjustment and inspection unit 200.

[0013] The engine control unit 312 is electrically connected to the conveying roller drive motor 311 and the switching unit drive unit 141. The switching unit drive unit 141 drives the switches 131, 132, 133, and 134. The engine control unit 312 is further electrically connected to the first post-fixing sensor 153, the second post-fixing sensor 163, the inversion sensor 137, and the engine unit 140. The engine control unit 312 controls the engine unit 140 to execute the image forming process (including the sheet feeding process). The engine unit 140 has a yellow station 120, a magenta station 121, a cyan station 122, and a black station 123. The engine unit 140 further has a sheet cassette 113, an intermediate transfer belt 106, a secondary transfer outer roller 114, a first fixing unit 150, and a second fixing unit 160.

[0014] 1, the image forming apparatus 1 conveys a sheet S conveyed from a sheet cassette 113 to an image forming unit, and forms a toner image on the sheet S. The image forming apparatus 1 conveys the sheet S, on which the toner image has been formed in the image forming unit 102, to a first fixing device 150 and a second fixing device 160, and fixes the unfixed toner on the sheet S to the sheet S by applying heat and pressure. The sheet S includes paper such as thin paper and thick paper, plastic films such as overhead projector sheets (OHP), surface-treated papers such as coated paper, sheets of special shapes such as envelopes, and cloth.

[0015] The image forming unit 102 has stations 120, 121, 122, and 123, and forms an image on a sheet transported by the sheet transport unit 10. The image forming apparatus 1 includes an intermediate transfer belt 106 and a secondary transfer outer roller 114. The stations 120, 121, 122, and 123 form yellow, magenta, cyan, and black toner images on the intermediate transfer belt 106, respectively. The configurations of the stations 120, 121, 122, and 123 are the same except for the toner colors. Therefore, the configuration of the station 120 will be described as an example here, and descriptions of the configurations of the other stations 121, 122, and 123 will be omitted.

[0016] The station 120 has a rotating photosensitive drum 105. Around the photosensitive drum 105, a charger 111, a laser scanner 107, a developing device 112, and a primary transfer roller 118 are arranged. The charger 111 uniformly charges the surface of the photosensitive drum 105. The laser scanner 107 has a laser driver (not shown) that turns on / off a laser beam emitted from a semiconductor laser according to image data supplied from the printer controller 103. The laser beam emitted from the semiconductor laser is deflected in the main scanning direction by a rotating polygon mirror (not shown). The laser beam deflected in the main scanning direction is guided to the surface of the photosensitive drum 105 by a reflecting mirror, and exposes the uniformly charged surface of the photosensitive drum 105 in the main scanning direction. As a result, an electrostatic latent image is formed on the surface of the photosensitive drum 105 according to the image data.

[0017] The developing device 112 develops the electrostatic latent image on the surface of the photosensitive drum 105 with yellow (Y) toner to form a yellow (Y) toner image. A voltage of the opposite polarity to that of the toner image is applied to the primary transfer roller 118, which transfers the yellow (Y) toner image on the surface of the photosensitive drum 105 onto the intermediate transfer belt 106. Similarly, a magenta (M) toner image, a cyan (C) toner image, and a black (K) toner image formed by the magenta station 121, the cyan station 122, and the black station 123 are sequentially transferred onto the intermediate transfer belt 106. The yellow (Y), magenta (M), cyan (C), and black (K) toner images are transferred onto the intermediate transfer belt 106 in a superimposed manner to form a full-color toner image.

[0018] Meanwhile, the sheet S fed from the sheet cassette 113 is conveyed to the secondary transfer outer roller 114 via the sheet conveying unit 10. The secondary transfer outer roller 114 presses the sheet S against the intermediate transfer belt 106, and simultaneously applies a bias having an opposite characteristic to that of the toner to the secondary transfer outer roller 114. As a result, the visible image formed on the intermediate transfer belt 106 is secondarily transferred to the sheet S fed in synchronization with the sub-scanning direction by the feeding process mechanism. Around the intermediate transfer belt 106, a start position detection sensor 115 for determining the print start position when forming an image, a feeding timing sensor 116 for timing the feeding of the sheet S, and a density sensor 117 for measuring the density of a patch during density control are arranged. When density control is performed, the density sensor 117 measures the density of each patch.

[0019] The image forming apparatus 1 has a first fixing device 150 and a second fixing device 160 for fixing the toner image transferred to the sheet S by heat and pressure. The first fixing device 150 has a fixing roller 151 for applying heat to the sheet S, a pressure belt 152 for pressing the sheet S against the fixing roller 151, and a post-fixing sensor 153 for detecting the completion of fixing. The fixing roller 151 is a hollow roller having an internal heater, and conveys the sheet S while being driven to rotate. The second fixing device 160 is located downstream of the conveying path of the sheet S from the first fixing device 150, and is arranged for the purpose of adding gloss to the toner image on the sheet S fixed by the first fixing device 150 and ensuring fixability. The second fixing device 160 also has a fixing roller 161, a pressure roller 162, and a post-fixing sensor 163, like the first fixing device 150.

[0020] Depending on the type of sheet S, there are some that do not need to pass through the second fixing device 160. In this case, in order to reduce energy consumption, a conveying path 130 is provided for discharging the sheet S without passing through the second fixing device 160. The sheet S can be guided to the conveying path 130 by a switch 131.

[0021] The switch 132 switches whether the sheet S, which has been transported through the image forming unit 102, the first fixing unit 150, and the second fixing unit 160, is guided to the outside of the image forming apparatus 1 or to the transport path 135. In the case of single-sided printing, the sheet S passes through the image forming unit 102, the first fixing unit 150, and the second fixing unit 160, and after image formation is completed, the switch 132 guides the sheet S to a discharge path 139 and discharges it to the outside.

[0022] In the case of double-sided printing, the sheet S is inverted after one side has been printed, and is transported again to the image forming unit 102. Specifically, the switch 132 guides the sheet S after fixing to a transport path 135, and transports it to an inverting unit 136. When an inversion sensor 137 detects the rear end of the sheet S, a switch 133 switches the transport direction of the sheet S to a transport path 138. The inverted sheet S is transported again to the image forming unit 102 via the transport path 138, and further to the first fixing unit 150 and the second fixing unit 160. The sheet S after double-sided printing is guided by the switch 132 to a discharge path 139, and is discharged to the outside.

[0023] For example, in the double-sided printing mode, in order to print an adjustment chart (measurement test pattern) on the second side of the sheet S after the adjustment chart (measurement test pattern) is printed on the first side of the sheet S, the switch 132 switches the destination of the sheet S to the conveying path 135. The sheet S conveyed to the conveying path 135 is conveyed to the inversion unit 136. After the rear end of the sheet S conveyed to the inversion unit 136 is detected by the inversion sensor 137, the conveying direction of the sheet S is reversed. The switch 133 switches the destination of the sheet S to the conveying path 138. This inverts the front and back of the sheet S. The sheet S is conveyed from the conveying path 138 to the secondary transfer nip between the intermediate transfer belt 106 and the secondary transfer outer roller 114. The adjustment chart is transferred to the second side of the sheet S at the secondary transfer nip. The sheet S with the adjustment charts printed on both sides is conveyed from the discharge path 139 to the adjustment inspection unit 200.

[0024] [Document reading unit] As shown in FIG. 1, the image forming system 100 has a document reading unit 190 connected to the image forming apparatus 1. The structure of the document reading unit 190 will be described with reference to FIGS. 3(a) and 3(b). FIG. 3(a) shows a state in which the CIS 501 is located at a reference position, and FIG. 3(b) shows a state in which the CIS 501 is located at a maximum movement position. In order to read an image of a sheet-like document D, the document reading unit 190 is provided with a document table glass 503 on which the document D is stacked. As shown in FIGS. 3(a) and 3(b), the CIS 501 provided in a frame 507 reads an image of the document D while moving from the left to the right in the figure.

[0025] A carriage 518 that holds the CIS 501 is held so as to be slidable in the axial direction with a slide guide shaft 519 as a reference, and is driven and stopped by a carriage motor 526 (see FIG. 2) and an HP sensor 521 (see FIG. 2). The CIS 501 is a well-known contact image sensor. In the CIS 501, a light emitting section having a light source irradiates light toward the document D, and a rod lens array or the like collects reflected light from the document D on a light receiving section on a line. On the CIS control board, the collected reflected light is photoelectrically converted and amplified, and a digital image signal is transmitted from a connector. The image signal is transmitted to the relay board 513 by an FFC 514 (flexible flat cable) connected to a connector 550 of the CIS 501. A shielded cable is adopted for the FFC 514 in response to the increase in size of the CIS 501 and the improvement in communication speed. The FFC 514 has a higher rigidity than an unshielded cable by the thickness of the shield. The relay board 513 is a board that relays image signals from the CIS 501 to a control unit 560 (see FIG. 2) of the document reading unit 190, and is fixed at a position where it does not interfere with the moving carriage 518.

[0026] [Adjustment and Inspection Unit] An adjustment inspection unit 200, which is an example of the image reading device shown in Fig. 1, is disposed downstream of the image forming apparatus 1. The adjustment inspection unit 200 is disposed downstream of the image forming apparatus 1 in the conveying direction of the sheet S. Fig. 4 is a cross-sectional view of the adjustment inspection unit 200. The adjustment inspection unit 200 has a first conveying roller 201 that receives the sheet S conveyed from an upstream device and conveys it, an adjustment inspection section 400 that reads the image printed on the sheet S and performs an adjustment inspection, and a second conveying roller 205 that conveys the sheet S to a downstream device.

[0027] [Adjustment and Inspection Department] The structure of the adjustment inspection unit 400 will be described with reference to FIG. 5. The adjustment inspection unit 400 is a section that has a function of measuring the shape of the sheet S and the shape and positional relationship of the image pattern printed on the sheet S, providing feedback to the image forming apparatus 1, and detecting abnormalities in the image information printed on the sheet S. A contact image sensor (hereinafter, CIS) is used as a reading sensor unit for acquiring image information. As the CIS 401, a long type is arranged because it is necessary to read the image of the entire sheet S, including the conveyance variation in the main scanning direction of the sheet S. In this embodiment, a long type CIS that can read up to a width of 350 mm is applied as the CIS 401 in order to read a sheet with a width of, for example, 13 inches (330.2 mm).

[0028] The adjustment inspection unit 400 includes pairs of conveying rollers 202, 203, and 204 for reading at a stable conveying speed. The first conveying roller 201, the pairs of conveying rollers 202, 203, and 204, and the second conveying roller 205 are an example of a conveying unit 210 that conveys the sheet S along the conveying path. Since it is necessary to read the measurement test patterns formed on the front and back sides of the sheet S almost simultaneously, a first-side reading unit 901 and a second-side reading unit 902 are disposed opposite to the sheet path. The first-side reading unit 901 includes a CIS 401, a reading glass 403 for stabilizing the position of the CIS 401 in the focal depth direction, and a housing 407. The reading glass 403 is also a conveying guide member that forms a part of the conveying path, and is made of glass and is an example of a transparent member. The housing 407 is an example of a conductive case and is made of metal. In this embodiment, the reading glass 403 is attached to the housing 407, and the housing 407 has a bottom plate portion 407a which faces the reading glass 403.

[0029] The CIS 401 housed in the housing 407 reads an image of the sheet S through a reading glass 403. Similarly, the second-side reading unit 902 has a CIS 402, a reading glass 404 which also serves as a transport guide member, and a CIS frame 408. Also, a black backing roller 405 is disposed opposite the first-side reading unit 901 to clarify the contrast with the edge of the sheet during reading, and a backing roller 406 is disposed opposite the second-side reading unit 902.

[0030] [Front and back registration feedback configuration] Next, the measurement at the time of front and back registration by the adjustment inspection unit 400 and the feedback of the measurement results will be described. Fig. 6 is an example of a paper library screen 1001 displayed on the operation unit 180. When the image forming apparatus 1 receives a request from a print position adjustment button 1002 in the paper library screen 1001 by operating the operation unit 180, it starts outputting a front test pattern 802 and a back test pattern 803 (see Fig. 7) for front and back registration. In the adjustment inspection unit 400, the sheet S on which the front test pattern 802 and the back test pattern 803 are formed is continuously read by the CIS 401, 402 while being fed by the conveyance roller pairs 202, 203, 204, and a measurement is made from the detected image.

[0031] The detection coordinates (X 01 ,Y 01 )~(X 31 ,Y 31 ) and the detection coordinates (X 41 ,Y 41 )~(X 71 ,Y 71 ) is detected. Based on the detection result, the image processing unit 260 measures the amount of image distortion and the positional deviation from the sheet S, and calculates geometric adjustment parameters (lead position, side position, magnification, perpendicularity, amount of rotation, etc.) that can instruct the image shape correction unit 320 to correct the shape. The geometric adjustment values ​​calculated by the image processing unit 260 are sent to the paper library 800 in the image forming apparatus 1 via the communication unit, and are stored as front surface parameters and back surface parameters in front surface geometric adjustment amounts 804 and back surface geometric adjustment amounts 805 (see FIG. 8).

[0032] As shown in Fig. 8, the paper settings 810 in the paper library 800 obtained in this manner are used when executing a print job using the same paper. This makes it possible to correct the image position and distortion and output a print image in which the front and back print positions have been corrected with high accuracy. The printing of the front test pattern 802 and the back test pattern 803 exemplified in the explanation can be, for example, a test output that is performed as a setup before a print job. Alternatively, it may be a test output that is automatically inserted at a predetermined timing during a print job as a calibration.

[0033] [Inspection process] The flow of the inspection process by the adjustment and inspection section 400 will be described. FIG. 9 is a cross-sectional view of a configuration in which the adjustment and inspection unit 200 and a stacking device 601 are connected as a post-processing device. During the inspection process, an image read by the adjustment and inspection section 400 is sent as a signal to the external PC 350, and compared with pre-registered images and registered data to detect stains and printing errors. When the sheet is inspected and determined to be a correct image without printing errors, the sheet is conveyed along a conveying path 612 by conveying roller pairs 610 and 611 and stacked on a first stacking section 613. Alternatively, a sheet detected as having a printing error is switched to a conveying path 615 by a switching section 614, and stacked on a second stacking section 618 by conveying roller pairs 616 and 617. The above flow makes it possible to automatically sort and stack defective printed matter. Alternatively, it is also possible to have the adjustment and inspection unit 400 read the images, perform an inspection process, leave only a data log of printing errors, and stack all the printed matter on the first stack unit 613.

[0034] [Reading section] Next, the configuration of the first side reading unit 901 will be described with reference to Figs. 10(a) and (b). The CIS 401 is movable between a reading position (Fig. 10(a)), which is a first position for reading an image on a sheet, and a shading position (Fig. 10(b)), which is a second position for performing shading. In this embodiment, a black backing roller 405 is disposed at a position facing the first side reading unit 901, and a black backing roller 406 is disposed at a position facing the second side reading unit 902 (see Fig. 5). That is, the backing rollers 405 and 406 are an example of a facing member, and are disposed at a position facing the CIS 401 located at the reading position via the reading glass 403.

[0035] FIG. 10(a) is a cross-sectional view of the first-side reading unit 901 showing a state in which the CIS 401 has moved to the reading position. The first-side reading unit 901 has the reading glass 403, the housing 407, the CIS 401, the carriage 418, and the moving mechanism 460. The carriage 418 is an example of a support member that supports the CIS 401. The carriage 418 is movable in a first direction D1 along the reading surface of the reading glass 403 and a second direction D2 opposite to the first direction D1. Here, the reading surface is the upper surface of the reading glass 403 in FIG. 10(a) (the surface opposite to the CIS 401), and is the surface of the reading glass 403 that comes into contact with the sheet. In this embodiment, the first direction D1 is the sheet conveying direction. The moving mechanism 460 is capable of moving the CIS 401 between the reading position and the shading position via the carriage 418. The moving mechanism 460 will be described later.

[0036] The CIS 401 is a known contact image sensor. A light emitting unit 411a having a light source irradiates light toward the sheet S, and a rod lens array or the like collects reflected light from the sheet S on a line of light receiving units 411b. That is, the CIS 401 is an example of a reading unit, has a light receiving unit 411b which is an example of a reading sensor that reads an image of a sheet conveyed on a conveying path through a reading glass 403, and is housed in a housing 407. Then, in the CIS control board 450, the reflected light collected by the light receiving unit 411b is photoelectrically converted, amplified by an amplifier (not shown), and converted into a digital signal by an AD converter (not shown) to generate image data. Furthermore, the image data is transmitted via a connector 412. The CIS 401 has an abutting unit 455 that abuts against the reading glass 403 in order to keep the distance from the reading glass 403 constant.

[0037] In this embodiment, the housing of the CIS 401 has a highly rigid structure in the main scanning direction. This prevents the long type CIS 401 from bending even in the central part in the main scanning direction away from the abutment part 455, and ensures the distance from the reading glass 403.

[0038] The CIS 401 is connected to a relay board 413 fixed to the outside of the housing 407 by a first FFC 414 (flexible flat cable) and a second FFC 415 for communication (see FIG. 11). The first FFC 414 and the second FFC 415 are examples of a flexible flat cable. In addition, two FFCs are often provided as the CIS 401 becomes larger and communication speed increases in recent years. The first FFC 414 and the second FFC 415 are shielded cables as the CIS 401 becomes larger and communication speed increases. The first FFC 414 and the second FFC 415 are higher in rigidity than an unshielded cable by the thickness of the shield. The shape of the first FFC 414 will be illustrated and described below in FIG. 10 and the like, but the same is true for the second FFC 415. In this embodiment, the first FFC 414 and the second FFC 415 are both single-sided shielded FFCs, but the present invention is not limited to this, and a double-sided shielded FFC or an unshielded FFC may be used.

[0039] The configuration of this embodiment will be specifically described below. For the sake of explanation, the up-down direction of the first-side reading unit 901 in the drawings in Figs. 10 to 14 will be described as the up-down direction of the first-side reading unit 901, but this does not necessarily coincide with the up-down direction of the actual first-side reading unit 901.

[0040] The first FFC 414 has a first end 414a and a second end 414b different from the first end 414a. The first end 414a is connected to a connector 412 which is a connection part provided in the CIS 401. In this embodiment, the connector 412 is disposed on the outer wall surface 401a of the CIS 401 on the opposite side (lower side) from the reading glass 403. The second end 414b is connected to a connector 459 which is a connection part provided in the relay board 413. The relay board 413 is an example of a board, and transmits and relays image data from the CIS 401 to the control board 250 of the adjustment inspection unit 200.

[0041] The route of the first FFC 414 is connected from the connector 412 on the CIS control board 450, arranged along the CIS control board 450 (first straight portion 451), and is bent and deflected in a direction approaching the reading glass 403 side (second straight portion 452). Further, it is bent and deflected substantially horizontally near the reading glass 403 (third straight portion 453), held horizontally by the holder 454, and released to the outside of the carriage 418. Then, it is inverted inside the housing 407 (curved portion 434), made to run along the bottom surface of the housing 407 (extended portion 435), folded back toward the outside of the housing 407, and connected to the connector 459 on the relay board 413. As a result, in this embodiment, the first straight portion 451, the second straight portion 452, and the third straight portion 453 are arranged in a substantially Z shape when viewed from the sheet width direction perpendicular to the first direction D1.

[0042] It should be noted that the curved portion 434 and the extended portion 435 are portions that are expressed relative to the shape of the first FFC 414, and move with the movement of the CIS 401, and do not represent fixed positions in the first FFC 414. Also, the first straight portion 451, the second straight portion 452, and the third straight portion 453 are all intended to include not only exact straight lines, but also approximate straight lines that are slightly curved from an exact straight line.

[0043] The holder 454 is provided on an upper portion of a wall portion on the first direction D1 side of the carriage 418. The holder 454 is an example of a passing portion, and allows the first FFC 414 to pass through it so as to head in the first direction D1. The holder 454 is disposed on the side of the reading glass 403 (above) relative to the connector 412.

[0044] The holder 454 is made of a ferrite core. The holder 454 is made of a magnetic material and has a substantially rectangular through hole through which the first FFC 414 can pass, and serves as a noise filter, holding the first FFC 414 horizontally by passing it through the hole. That is, the holder 454 is made of a magnetic material having a noise filter function, and has a hole shape that penetrates along the first direction D1 and allows the first FFC 414 to pass through. In this embodiment, the first FFC 414 is not fixed in all directions by the holder 454, but is freely movable at least in the first direction D1 and the second direction D2.

[0045] In this embodiment, the bottom plate portion 407a of the housing 407 has a through hole 407b arranged so that the first FFC 414 passes through it. Because the bottom plate portion 407a is a metal plate, the through hole 407b is provided with, for example, an edge cover made of resin that covers the edge of the through hole 407b. This makes it possible to prevent the first FFC 414 from coming into direct contact with the edge of the through hole 407b, causing wear or generating noise.

[0046] FIG. 10(b) is a cross-sectional view of the first-side reading unit 901 showing a state in which the CIS 401 has moved to the shading position. In order to perform shading correction, the CIS 401 moves to the shading position in the upstream direction. Here, the light source and rod lens array of the CIS 401 have uneven light quantities, and the light receiving unit 411b has uneven sensitivity, so that it may not be possible to perform uniform image reading. Therefore, in order to enable uniform image reading, a white reference plate 416 with a controlled color tone is placed over the entire surface, and the image data obtained from the output value of the CIS 401 is corrected for the image of the sheet S using the output value (data) when read by the CIS 401. This is shading correction. That is, the white reference plate 416 is placed at a position facing the CIS 401 located at the shading position via the reading glass 403, and is used for shading the CIS 401.

[0047] Shading correction is generally performed after optimizing the amount of light emitted from the light source that illuminates the sheet S and optimizing the amplification factor (gain) when amplifying the image signal output of the CIS 401. A series of corrections, including adjustments of the amount of light emitted and the gain, for the CIS 401 to uniformly read the image of the sheet S is called shading correction. The white reference plate 416 is provided on the surface of the reading glass 403 by a method such as printing, painting, or gluing or attaching with tape. Furthermore, a sheet guide member 417 is arranged so as to cover the white reference plate 416. The sheet guide member 417 is arranged on the conveying path side of the white reference plate 416, and guides the sheet conveyed by the conveying unit 210 (see FIG. 5) to between the backing roller 405 and the reading glass 403. Shading correction may be performed multiple times at a predetermined timing even during a job.

[0048] [Moving mechanism] Next, the moving mechanism 460 will be described in detail with reference to Figs. 11 to 14. Fig. 11 is a side view seen from the conveying direction of the sheet S, and Fig. 12 is a perspective view of the moving mechanism. Fig. 13 is an exploded perspective view of the moving mechanism, and Fig. 14 is a side view of the moving mechanism. The moving mechanism 460 supports the carriage 418 movably relative to the housing 407. The moving mechanism 460 has a guide shaft 419, a bush 461, a holder 470, and an earth plate 480.

[0049] The guide shaft 419 is an example of a support shaft, is made of, for example, metal and is conductive, and is attached to the housing 407 along the first direction D1 and the second direction D2. The bush 461 is an example of a moving part, is, for example, a cylindrical bearing made of, for example, metal and is conductive, and is supported so as to be axially movable relative to the guide shaft 419. The holder 470 is an example of a support base, and is formed of, for example, a non-conductive material such as non-conductive resin, and houses the bush 461 and supports the carriage 418.

[0050] In this embodiment, since the CIS 401 is a long type, the carriage 418 that holds it is made of metal having sufficient rigidity to prevent bending in the longitudinal direction. The carriage 418 is held via a holder 470 so as to be slidable in the axial direction with a guide shaft 419 as a reference. A sensor flag 420 for detecting the position of the carriage 418 is provided on a part of the carriage 418, and a photosensor 421 detects the transmission and blocking of light of the sensor flag 420 associated with the movement of the carriage 418. The stopping position of the carriage 418 is controlled based on the detection timing of the photosensor 421.

[0051] A belt holder 422 is provided on the carriage 418, which holds and fixes a part of a timing belt 423. The timing belt 423 is wound around a timing gear pulley 424 to transmit the driving force, and tension is applied by an idler pulley 425. The gear of the timing gear pulley 424 is driven by a motor gear 427 that transmits the driving force from a motor 426, which is a driving source. Therefore, the CIS 401 slides when driven by the motor 426, and the stop position is controlled by the photosensor 421, so that the CIS 401 can be driven and stopped reciprocally between the reading position and the shading position. As shown in FIG. 11, the first FFC 414 and the second FFC 415 are disposed on both ends in the main scanning direction, and are held through holes in the holder 454.

[0052] Next, the configuration of the holder 470 and the earth plate 480 will be described with reference to FIG. 13. The holder 470 has an accommodation hole 471 for accommodating the bush 461, an attachment surface 472 to which the earth plate 480 is attached, and a through-hole 473 that penetrates between the accommodation hole 471 and the attachment surface 472. The bush 461 is a bearing that slidably receives the guide shaft 419, and is made of metal from the inner circumference side to the outer circumference side of the housing, and is electrically conductive from the inserted guide shaft 419 to the outer circumference surface. The bush 461 is fixed by press-fitting into the accommodation hole 471. As a result, the bush 461 is fixed to the holder 470 with high accuracy and without backlash. Since the holder 470 is made of a non-conductive resin material with high toughness, it is unlikely to be damaged when the bush 461 is pressed into the holder 470, and is firmly fixed.

[0053] Earth plate 480 is an example of a first conductive member, and is made of, for example, metal and has electrical conductivity, and is interposed between carriage 418 and holder 470, and is in contact with and conductive to both carriage 418 and bush 461. Earth plate 480 is made of a generally rectangular annular plate material as a whole, and has main body portion 481 and contact portion 482. In other words, earth plate 480 is a metal leaf spring that has elasticity and is equipped with contact portion 482.

[0054] The main body 481 is interposed between the carriage 418 and the holder 470 and is in contact with the carriage 418. The main body 481 is attached to an attachment surface 472 of the holder 470. The contact portion 482 is integral with the main body 481, protrudes from the main body 481 toward the bush 461 closer to the bush 461 than the attachment surface 472, and is elastically in contact with the outer circumferential surface of the bush 461. In this embodiment, the through portion 473 of the holder 470 has a shape in which an edge portion is cut out from an end portion on one side of the axial direction (first direction D1) of the holder 470, and the contact portion 482 contacts the bush 461 via the through portion 473.

[0055] An earth plate 480 is sandwiched between the holder 470 and the carriage 418, and the earth plate 480 is fixed to the carriage 418 by a screw 464. When assembled in this manner, the contact portion 482 is pressed against the bush 461 in the through portion 473 of the holder 470, providing electrical continuity. Note that, in this embodiment, the through portion 473 is described as having a shape cut out from the edge of the holder 470, but is not limited thereto, and may be a through hole that passes through the accommodation hole 471 and the mounting surface 472.

[0056] Also, a CIS leaf spring 490 that contacts the housing of the CIS 401 and conducts electricity between the CIS 401 and the carriage 418 is attached to the carriage 418. The CIS leaf spring 490 is an example of a second conductive member and has electrical conductivity. The CIS leaf spring 490 is a leaf spring compressed between the CIS 401 and the carriage 418, and has a contact portion 491 that elastically deforms and contacts the CIS 401. The biasing force of the contact portion 491 of the CIS leaf spring 490 is not strong enough to press the CIS 401 against a reference surface to position it, but may be strong enough to allow the contact portion 491 to maintain a contact state even if the CIS 401 is tilted. Also, in this embodiment, a case where the CIS leaf spring 490 is applied as the second conductive member is described, but this is not limited thereto, and the CIS 401 and the carriage 418 may be conductively connected using, for example, a cable or the like.

[0057] Fig. 14 shows a cross section of the periphery of the carriage 418 of the first-side reading section 901. In Fig. 14, the connection earth path between the CIS 401 and the carriage 418 is indicated by a thick solid line. The connection earth path is connected in the order of the housing of the CIS 401, CIS leaf spring 490 → carriage 418 → earth plate 480 → bush 461 → guide shaft 419 → housing 407, and is grounded from the housing 407 via the device main body of the adjustment and inspection unit 200. The CIS 401 and carriage 418 are configured to be grounded via such a path.

[0058] As described above, according to the adjustment and inspection unit 200 of this embodiment, the carriage 418 is grounded via the moving mechanism 460. The carriage 418 is movable, but is configured to be reliably grounded at any position with a simple configuration. For example, the carriage 418 can be reliably grounded even while it is moving due to a shading operation. According to this embodiment, there is no need to provide a dedicated cable for grounding, so the carriage 418 can be grounded without increasing the size of the first-side reading unit 901 or the number of parts.

[0059] According to the adjustment / inspection unit 200 of this embodiment, the holder 470 is made of a non-conductive resin material, which is advantageous in terms of durability and resistance to cracking compared to a case where the holder 470 is made of a conductive resin material. Even if the holder 470 is non-conductive, the contact portion 482 of the earth plate 480 in contact with the carriage 418 is conductive to the bush 461 via the through portion 473 of the holder 470, so that the conductivity can be guaranteed with a simple structure.

[0060] Furthermore, according to the adjustment and inspection unit 200 of this embodiment, the contact portion 482 of the ground plate 480 is elastically pressed against the bush 461, thereby preventing poor contact between the ground plate 480 and the bush 461. Similarly, the contact portion 491 of the CIS leaf spring 490 is elastically pressed against the CIS 401, thereby preventing poor contact between the CIS leaf spring 490 and the CIS 401.

[0061] Furthermore, according to the adjustment and inspection unit 200 of this embodiment, the carriage 418 and the CIS 401 are electrically connected by the CIS leaf spring 490. Therefore, the CIS 401 can be grounded without increasing the size of the first-side reading section 901 or the number of parts.

[0062] In the above-described embodiment, the moving part is a cylindrical bush 461, but this is not limited thereto. For example, a configuration may be applied in which the moving part is a ball screw, the support shaft is a screw shaft, and the moving part is moved in the axial direction by rotating the support shaft.

[0063] In the above embodiment, the moving mechanism 460 of the carriage 418 is described as grounding the carriage 418 to the housing 407 via the ground plate 480, the bush 461, and the guide shaft 419, but the present invention is not limited to this. For example, the carriage 418 may be directly conductive to the bush 461. That is, regardless of the configuration of the moving mechanism, it is sufficient that the carriage 418 is grounded via the moving mechanism 460. With such a configuration, there is no need to provide a dedicated cable for grounding, and therefore the carriage 418 can be grounded without increasing the size of the first-side reading unit 901 or the number of parts. [Explanation of symbols]

[0064] 1...image forming apparatus, 100...image forming system, 102...image forming section, 210...conveying section, 401...CIS (reading unit), 403...reading glass (transparent member), 405, 406...backing roller (opposing member), 407...housing (case), 411b...light receiving section (reading sensor), 416...white reference plate, 417...sheet guide member, 418...carriage (support member), 419...guide shaft (support shaft), 460...moving mechanism, 461...bush (bearing, moving section), 470...holder (support base), 471...accommodating hole, 472...mounting surface, 473...through portion, 480...earth plate (first conductive member), 481...main body, 482...contact portion, 490...CIS leaf spring (second conductive member)

Claims

1. A conductive case; a reading unit that has a reading sensor that reads an image on a sheet being conveyed and is housed in the case; a conductive support member for supporting the reading unit; a moving mechanism that supports the support member movably relative to the case, The moving mechanism includes: A support shaft having electrical conductivity and attached to the case; a moving part that is electrically conductive and supported so as to be movable in the axial direction relative to the support shaft; a support base formed of a non-conductive material, which houses the moving part and supports the support member; a first conductive member that is conductive and is interposed between the support member and the support base, and that electrically connects the support member and the moving portion; The support member and the case are electrically connected to each other.

1. An image reading apparatus comprising:

2. The first conductive member is a main body portion interposed between the support member and the support base and in contact with the support member; a contact portion that protrudes from the main body portion toward the moving portion and has elasticity to be biased into contact with the moving portion, 2. The image reading apparatus according to claim 1, wherein the image reading apparatus comprises:

3. The moving part is a bearing.

3. The image reading apparatus according to claim 2, wherein the image reading apparatus comprises:

4. The support base is an accommodation hole for accommodating the bearing; a mounting surface to which the main body of the first conductive member is attached; a through-portion penetrating between the accommodation hole and the mounting surface, The contact portion contacts the bearing via the through portion.

4. The image reading apparatus according to claim 3,

5. The bearing is fixed in the receiving hole by press-fitting.

5. The image reading apparatus according to claim 4,

6. a second conductive member having electrical conductivity and electrically connecting the reading unit and the support member; 2. The image reading apparatus according to claim 1, wherein the image reading apparatus comprises:

7. the second conductive member is a leaf spring compressed between the reading unit and the support member; 7. The image reading apparatus according to claim 6,

8. the moving mechanism is capable of moving the reading unit via the support member to a first position for reading an image on a sheet and a second position for performing shading, A conveying unit that conveys the sheet along a conveying path; a transparent member that forms a part of the transport path and is supported by the case; an opposing member disposed at a position opposing the reading unit located at the first position with the transparent member interposed therebetween; a white reference plate that is disposed at a position facing the reading unit located at the second position with the transparent member interposed therebetween and is used for shading the reading unit; a sheet guide member that is disposed on the conveying path side of the white reference plate and that guides the sheet conveyed by the conveying unit to a position between the opposing member and the transparent member; 2. The image reading apparatus according to claim 1, wherein the image reading apparatus comprises:

9. an image forming apparatus having an image forming unit that forms an image on a sheet; and the image reading device according to claim 1 , which reads an image on a sheet on which an image has been formed in the image forming unit.

1. An image forming system comprising:

Images