Sheet conveying apparatus, image reading apparatus, and image forming apparatus

Abstract

The invention relates to a sheet conveying apparatus, an image reading apparatus, and an image forming apparatus. The sheet conveying device includes: a conveying member; a separation member; a driving roller including a plurality of first rotating members; a motor; a driven roller including a plurality of second rotating members and a shaft member supporting the plurality of second rotating members; a holder member configured to regulate a position of the central second rotating member; and an urging spring configured to urge the retainer member. The retainer member includes (i) a first side surface portion provided with a first shaft receiving portion and (ii) a second side surface portion provided with a second shaft receiving portion. The retainer member is configured to regulate a position of the central second rotating member by first and second side surface portions, and apply an urging force of the urging spring to the shaft member via first and second shaft receiving portions.

Description

Technical Field

[0001] This disclosure relates to a sheet conveying apparatus for conveying sheets, an image reading apparatus for reading images from sheets, and an image forming apparatus for forming images on recording material. Background Technology

[0002] Japanese Patent Application Publication No. 2023-054431A discloses an image reading device capable of reading images while conveying small-sized originals such as business cards. In this image reading device, an original, fed from an original tray by a feed roller, passes through a separation section and is conveyed toward a reading unit by a pair of transfer rollers. The transfer roller pair includes a drive roller and a driven roller, the drive roller having a plurality of roller elements spaced apart in the width direction, and the driven roller having a plurality of roller elements spaced apart in the width direction.

[0003] In the aforementioned literature, standard-sized originals are conveyed simultaneously by all roller elements of both the drive and driven rollers, while small-sized originals are held only by roller elements located at the center of both the drive and driven rollers. Therefore, the conveying force applied to small-sized originals by the conveyor rollers is less than the conveying force applied to standard-sized originals. Consequently, depending on the relationship between the conveying force applied to the originals by the conveyor rollers and the frictional resistance experienced by the originals in the separation section, the stability of original conveying may decrease. Summary of the Invention

[0004] The present invention provides a sheet conveying device that can more stably convey small-sized sheets.

[0005] One aspect of the present invention provides a sheet conveying device, comprising: a conveying member configured to convey a sheet; a separating member configured to form a separating portion together with the conveying member and to separate sheets one by one in the separating portion; a drive roller disposed downstream of the separating portion in a sheet conveying direction, the drive roller including a plurality of first rotating members arranged in a sheet width direction orthogonal to the sheet conveying direction; a motor configured to drive the drive roller; a driven roller configured to rotate following the drive roller, the driven roller including a plurality of second rotating members respectively contacting the plurality of first rotating members and a shaft member supporting the plurality of second rotating members; a retainer member configured to control the position of a central second rotating member disposed at the center in the sheet width direction among the plurality of second rotating members; and a push spring. The push spring is configured to push the retainer component such that the plurality of second rotating components press against the plurality of first rotating components, wherein the retainer component includes: (i) a first side surface portion facing the end face of the central second rotating component on one side in the sheet width direction and having a first shaft receiving portion for receiving the shaft component; and (ii) a second side surface portion facing the end face of the central second rotating component on the other side in the sheet width direction and having a second shaft receiving portion for receiving the shaft component, wherein the retainer component is configured to control the position of the central second rotating component in the sheet width direction through the first side surface portion and the second side surface portion, and to apply the pushing force of the push spring to the shaft component via the first shaft receiving portion and the second shaft receiving portion.

[0006] Another aspect of the present invention provides a sheet conveying apparatus, comprising: a conveying member configured to convey a sheet; a separating member configured to form a separating portion together with the conveying member and to separate sheets one by one in the separating portion; a drive roller disposed downstream of the separating portion in a sheet conveying direction, the drive roller including a plurality of first rotating members arranged in a sheet width direction orthogonal to the sheet conveying direction; a motor configured to drive the drive roller; a driven roller configured to rotate following the drive roller, the driven roller including a plurality of second rotating members respectively contacting the plurality of first rotating members and a shaft member supporting the plurality of second rotating members; a retainer member configured to control the position of two second rotating members disposed at a central portion in the sheet width direction among the plurality of second rotating members; and a push spring. A spring, the push spring being configured to push the retainer component such that the plurality of second rotating components press against the plurality of first rotating components, wherein the retainer component includes: (i) a first side surface portion facing one of the two second rotating components in the sheet width direction and having a first shaft receiving portion for receiving the shaft component; and (ii) a second side surface portion facing the other of the two second rotating components in the sheet width direction and having a second shaft receiving portion for receiving the shaft component; wherein the retainer component is configured to control the position of the two second rotating components in the sheet width direction via the first side surface portion and the second side surface portion, and to apply the pushing force of the push spring to the shaft component via the first shaft receiving portion and the second shaft receiving portion.

[0007] Another aspect of the present invention provides a sheet conveying apparatus comprising: a conveying member configured to convey a sheet; a separating member configured to form a separating portion together with the conveying member and to separate sheets one by one in the separating portion; a drive roller disposed downstream of the separating portion in a sheet conveying direction, the drive roller including a plurality of first rotating members arranged in a sheet width direction orthogonal to the sheet conveying direction; a motor configured to drive the drive roller; a driven roller configured to follow rotation of the drive roller, the driven roller including a plurality of second rotating members respectively contacting the plurality of first rotating members and a shaft member supporting the plurality of second rotating members; a retainer member configured to cover a central second rotating member disposed at the center of the plurality of second rotating members in the sheet width direction from a side opposite to the drive roller; and a push spring configured to push the retainer member such that the plurality of second rotating members press against the plurality of first rotating members, wherein the push spring is a single push spring that pushes the driven roller to press the plurality of first rotating members and the plurality of second rotating members against each other.

[0008] Further features of the invention will become apparent from the following description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of an image forming apparatus according to the first embodiment.

[0010] Figure 2 This is a perspective view of the image reading device according to the first embodiment.

[0011] Figure 3 This is a schematic diagram of an image reading device according to the first embodiment.

[0012] Figure 4 This is a cross-sectional view of the ADF according to the first embodiment.

[0013] Figure 5 This is a view showing the interior of the ADF according to the first embodiment.

[0014] Figure 6A This is a cross-sectional view of the ADF according to the first embodiment.

[0015] Figure 6B This is a perspective view of the driven roller retainer according to the first embodiment.

[0016] Figure 7 This is a cross-sectional view of the ADF according to the second embodiment. Detailed Implementation

[0017] In the following description, embodiments according to the present disclosure will be described with reference to the accompanying drawings.

[0018] First Embodiment

[0019] First, refer to Figures 1 to 3 The image forming apparatus 100 and image reading apparatus 101 according to the first embodiment are described. The image forming apparatus 100 is an electrophotographic multifunction printer that has a copying function that reads an image from an original document by means of the image reading apparatus 101 and forms an image on a recording material P based on the acquired image information. However, "image forming apparatus" can be a single-function printer, fax machine, commercial printer, etc., that only has a printing function. In addition, "image forming apparatus" can be, for example, an inkjet printer that includes an inkjet printing unit as an image forming part.

[0020] Figure 1 This is a schematic diagram of an image forming apparatus 100 according to the first embodiment. The image forming apparatus 100 includes a printer body 104, which serves as the main body of the image forming apparatus, and an image reading device 101 disposed above the printer body 104. The printer body 104 includes an image forming section 120, which serves as an electrophotographic image forming engine, a feed cassette 105 for containing recording material P, a transport mechanism for transporting the recording material P, and a sheet discharge tray 119. As the recording material P (recording medium), various sheets with different sizes and materials can be used, such as paper including plain paper and thick paper, surface-treated sheets (e.g., coated paper), sheets with special shapes (e.g., envelopes and index paper), plastic film, cloth, etc.

[0021] The image forming section 120 includes image forming units 111, 112, 113, and 114 (processing units), exposure units 107, 108, 109, and 110, a transfer unit, and a fixing unit 118. Each of the image forming units 111 to 114 includes a photosensitive drum as an image carrier (photosensitive component), and a charging unit, a developing unit, and a cleaning unit acting on the photosensitive drum to perform charging, developing, and cleaning steps in electrophotographic processing. The transfer unit includes an intermediate transfer belt 115 as an intermediate transfer component, a secondary transfer roller 116 forming a secondary transfer section together with the intermediate transfer belt 115, and a primary transfer roller facing each photosensitive drum across the intermediate transfer belt 115. The fixing unit 118 includes, for example, a fixing roller pair and a halogen lamp as a heat source.

[0022] The image forming apparatus 100 performs a series of operations (image forming operations) to form an image while transmitting recording material P, as described below. For example, when the original is placed on the original tray 200 of the image reading device 101, and the user presses the print execution button (copy button) of the operation unit, the image forming apparatus 100 performs the image forming operation and the image reading device 101 performs the reading operation.

[0023] In the image forming operation, the photosensitive drums and intermediate transfer belts 115 of each image forming unit 111 to 114 are driven to rotate. The surface of each photosensitive drum is uniformly charged by a charging unit. Exposure units 107 to 110 expose the surface of the photosensitive drum based on image information received from the image reading device 101 or from a host computer connected to the image forming apparatus 100 via a network. As a result, an electrostatic latent image corresponding to a monochrome image is formed on the surface of each photosensitive drum. The developing units of each image forming unit 111 to 114 develop the electrostatic latent image into a toner image using one of yellow, magenta, cyan, and black toners (developers). Furthermore, the toner image is transferred from the photosensitive drum to the intermediate transfer belt 115 via a primary transfer roller. At this time, multiple transfers are performed so that the toner images of various colors overlap each other, thereby forming a full-color toner image (hereinafter simply referred to as the toner image) on the intermediate transfer belt 115. The rotation of the intermediate transfer belt 115 transports the toner image toward the secondary transfer section.

[0024] On the other hand, the recording material P is fed from the feed cassette 105 via the feed roller 106 and conveyed toward the secondary transfer section. In the secondary transfer section, the toner image is transferred from the intermediate transfer belt 115 to the recording material P via the secondary transfer roller 116, which applies a predetermined transfer voltage. The recording material P that has passed through the secondary transfer section is conveyed to the fixing unit 118 by the pre-fixing transfer unit 117 and undergoes fixing processing, which involves heating and pressurizing the toner image. The recording material P that has passed through the fixing unit 118 is discharged as a product and stacked on the sheet discharge tray 119.

[0025] Image reading device

[0026] Next, we will refer to Figure 2 and Figure 3 Image reading device 101 is described. Image reading device 101 generally includes a reader 103 and an automatic original feeder 102 (hereinafter referred to as ADF 102) which is a sheet transport device according to this embodiment. The reader 103 is fixed to the upper part of the printer body 104. The ADF 102 is supported by the reader 103 and is configured to be able to open and close relative to the reader 103.

[0027] like Figure 2 and Figure 3As shown, the reader 103 includes a front reading unit 306 and a feed-reading glass 312. The front reading unit 306 includes a light source 310, a substrate 309 on which a charge-coupled device (CCD) as a light receiving element is disposed, and an optical system 308 that guides light from the original document and forms an image on the light receiving surface of the light receiving element.

[0028] ADF 102 includes a back-side readout unit 307 and a feed-readout glass 313. The back-side readout unit 307 is an image sensor unit that includes a light source, a sensor substrate on which CMOS circuitry as light-receiving elements are formed, and an optical system that forms an image on the light-receiving surface of the sensor substrate by light from the original document.

[0029] Each of the front reading unit 306 and the back reading unit 307 is an example of a reading unit that reads an image from an original document of a sheet conveyed by the conveying component of the ADF 102.

[0030] Additionally, the ADF 102 includes a manuscript tray 200, an opening / closing cover 315, multiple conveying guides including a separation guide 317, a housing 316, and a sheet discharge tray 201. Furthermore, the ADF 102 includes a pickup roller 300 (feed roller), a separation roller pair 301, a traction roller pair 302, a first reading roller pair 303, a second reading roller pair 304, and a sheet discharge roller pair 305 as conveying components for conveying manuscripts.

[0031] The opening / closing cover 315 serves as a second frame (second frame body) supported by the housing 316, which serves as a first frame (first frame body), in an openable and closable manner. The opening / closing cover 315 includes an upper cover portion 315u forming at least a portion of the upper surface of the ADF 102, and a transfer guide 316g (second guide portion) forming at least a portion of the transfer path CP together with a transfer guide 315g (first guide portion) disposed in the housing 316. The opening / closing cover 315 is movable (pivotable) relative to the housing 316 such that at least a portion of the transfer path CP is opened.

[0032] Pick-up roller 300, separation roller pair 301, traction roller pair 302, first reading roller pair 303, second reading roller pair 304, and sheet discharge roller pair 305 are arranged sequentially along the conveying path CP. In the following text, the direction in which the original is conveyed along the conveying path CP is referred to as the sheet conveying direction Dc. The direction along the sheet and orthogonal to the sheet conveying direction is referred to as the sheet width direction Dw. The sheet width direction Dw is approximately the same as the main scanning direction of the front reading unit 306 and the back reading unit 307, which serve as line sensors.

[0033] The original document tray 200 is an example of a placement section on which original documents, as sheets, are placed. The original document tray 200 is supported by a housing 316. The pick-up roller 300 is an example of a feed member that feeds original documents from the original document tray 200. The sheet discharge tray 119 is a stacking section on which original documents with read images are stacked. The sheet discharge roller pair 305 is an example of a discharge member that discharges original documents from the inside of the ADF 102 toward the sheet discharge tray 119.

[0034] The original document tray 200 is provided with side control plates 200a and 200b, which serve as a pair of control components for controlling the position of the original document in the sheet width direction Dw. The side control plates 200a and 200b are connected via an interlocking mechanism such as a rack and pinion, and are configured to move in a linked manner in the sheet width direction Dw. Furthermore, while moving, the side control plates 200a and 200b maintain a symmetrical positional relationship relative to the center of the original document tray 200 along the sheet width direction Dw (i.e., the distance from the control surface facing the original document to the center of the original document tray 200 is equal). ADF 102 is a center-based sheet conveying device that uses the center of the original document tray 200 in the sheet width direction Dw as the conveying center Wc to convey the original document so that the center of the original document in the sheet width direction Dw is aligned with the conveying center Wc. Figure 5 , Figure 6A and Figure 6B (Consistent). The transport center Wc is the reference for the sheet position of the original document transported by ADF 102 in the sheet width direction Dw.

[0035] According to this embodiment, a sheet material such as a business card (hereinafter referred to as a small-sized original) with a short length (hereinafter referred to as the sheet width) in the sheet width direction Dw can be placed on the original material tray 200, and the ADF 102 can transport the small-sized original. A small-sized original is a sheet material smaller than the sheet size of a typical original, and refers to, for example, an A6 size or smaller (sheet width of 105mm or smaller). Small-sized originals include originals with a sheet width of 55mm and a sheet length of 91mm (the size of a typical business card). Furthermore, the side control plates 200a and 200b can be moved to positions where they contact the two ends of the business card-sized original. Note that instead of the side control plates 200a and 200b, the width direction position of the small-sized original can be controlled by placing it on a dedicated auxiliary tray that can be detached from the original material tray 200.

[0036] The separating roller pair 301 includes a feed roller 301a for conveying the original document. Figure 3The separation roller 301b forms a separation portion Ns (separation clamping portion) between the feed roller 301a and the separation roller 301b. The feed roller 301a is an example of a conveying member that conveys the original in the sheet conveying direction. The feed roller 301a is driven rotatably by a drive source (motor) shared with the pick-up roller 300. The separation roller 301b is an example of a separation member that separates the original by applying frictional force to the original in the separation portion Ns. The separation guide 317 guides the leading edge of the original fed by the pick-up roller 300 toward the separation portion Ns.

[0037] The separating roller 301b is, for example, a roller component connected via a torque limiter to a fixed shaft (a non-rotating shaft component) supported by the housing 316. The separating component is not limited to this, and may, for example, be a pad-like elastic component (rubber pad) that contacts the feed roller 301a, or a delay roller that applies a driving force to it in the opposite direction to the sheet conveying direction via a torque limiter (delay drive).

[0038] The traction roller pair 302 is a conveying unit located downstream of the separation roller pair 301 in the sheet conveying direction Dc and further conveys the original received from the separation roller pair 301 in the sheet conveying direction Dc. In other words, the traction roller pair 302 is a conveying roller pair that overcomes the frictional force (frictional resistance) received by the original from the separation roller 301b in the separation section Ns in the direction opposite to the sheet conveying direction Dc and conveys the original.

[0039] The traction roller pair 302 includes a drive roller 302A and a driven roller 302B. The drive roller 302A receives driving force from a drive source disposed in the housing 316 and rotates, while the driven roller 302B rotates following the drive roller 302A. The detailed construction of the traction roller pair 302 will be described below.

[0040] According to this embodiment, the opening / closing cover 315 supports the pick-up roller 300, the feed roller 301a of the separating roller pair 301, and the driven roller 302B of the traction roller pair 302. The housing 316 supports a plurality of rollers including the drive roller 302A of the separating roller 301b and the traction roller pair 302. When the opening / closing cover 315 is closed, a conveying path CP is formed, and a clamping portion is formed for the separating roller pair 301 and the traction roller pair 302. In other words, the ADF 102 is allowed to convey the original document when the opening / closing cover 315 is closed.

[0041] The image reading device 101 performs an image reading operation (feed-read operation) while reading an image through the ADF 102. The reading operation begins when the user places an image on the image tray 200 and operates the operation unit to instruct the user to perform the reading operation. As the pickup roller 300 rotates in contact with the upper surface of the uppermost image on the image tray 200, the uppermost image is fed toward the separation roller pair 301. The fed image is guided by the separation guide 317 into the separation section Ns and further conveyed by the feed roller 301a in the sheet transport direction Dc. When multiple images enter the separation section Ns, the frictional force applied to the images by the separation roller 301b prevents images other than the uppermost image from passing through the separation section Ns. Thus, the individual images are conveyed sequentially along the transport path CP.

[0042] When the front end of the original document, which has passed through the separation section Ns, reaches the traction roller pair 302, the original document is further conveyed downstream in the sheet conveying direction Dc by the traction roller pair 302.

[0043] Here, the rotational drive of the pick-up roller 300 and the feed roller 301a can be stopped before the trailing edge of the original document in the sheet transport direction Dc passes the separation section Ns. This configuration prevents subsequent original documents from moving together with the original document being fed in the current feed operation. Furthermore, the transport speed of the traction roller pair 302 (the circumferential speed of the drive roller 302A) can be set to be faster than the transport speed of the separation roller 301b (the circumferential speed of the feed roller 301a). Therefore, the separation performance in the separation section Ns and the throughput of the reading operation can be improved. Each of the above configurations can be applied individually or in combination. When applying each of the above configurations, it is preferable that the traction roller pair 302 can apply a greater transport force to the original document in order to overcome the frictional resistance borne by the original document at the separation section Ns and transport the original document stably.

[0044] The original document, already conveyed by the traction roller pair 302, is transported via the first reading roller pair 303 and the second reading roller pair 304. In this process, the front reading unit 306, at a reading position between the first reading roller pair 303 and the second reading roller pair 304, optically scans the first side of the original document via the feed-reading glass 312 to read image information on the first side. When image information needs to be read from both sides of the original document, the back reading unit 307, at a reading position between the second reading roller pair 304 and the sheet discharge roller pair 305, optically scans the second side of the original document via the feed-reading glass 313 and reads image information on the second side. The original document, with its image information read, is discharged through the sheet discharge roller pair 305 to the outside of the housing 316 and stacked on the sheet discharge tray 201.

[0045] It should be noted that when the original document is placed on the platen glass on the upper surface of the reader 103 and the ADF 102 is closed, the image reading device 101 can perform the operation of reading image information (fixed reading operation) while moving the front reading unit 306 along the sub-scanning direction.

[0046] Pressing structure of traction roller pair

[0047] Reference Figure 4 , Figure 5 , Figure 6A and Figure 6B The construction and pressing structure of the traction roller pair 302 according to this embodiment are described in detail. Figure 4 It shows along Figure 2 A cross-sectional view of a portion of the section of ADF 102 taken from line AA (along the virtual plane of the transmission center Wc). Figure 5 This is a view showing the interior of the opening and closing cover 315, and a top view showing the state of the ADF 102 as viewed from above through the upper cover portion 315u of the opening and closing cover 315. Figure 6A It shows along Figure 2 A cross-sectional view of a portion of the section of ADF102 taken by line BB. Figure 6A A cross section of ADF 102 is shown in a virtual plane that includes the rotation axis of the drive roller 302A and the rotation axis of the driven roller 302B of the traction roller pair 302. Figure 6B This is a perspective view of the driven roller retainer 320.

[0048] like Figure 4 and Figure 6A As shown, the traction roller pair 302 includes a drive roller 302A and a driven roller 302B. Additionally, the ADF 102 includes a driven roller retainer 320 that contacts the driven roller 302B, and a pressure spring 318 that serves as a pressing member or a pressing spring for pressing the driven roller retainer 320 to press the clamping portion. The conveying unit according to this embodiment includes the traction roller pair 302, the driven roller retainer 320, and the pressure spring 318.

[0049] The drive roller 302A includes drive roller elements 331, 332, and 333 as a plurality of first rotating components arranged in the sheet width direction Dw, and a drive shaft 334 as a shaft component supporting the drive roller elements 331 to 333. The drive roller elements 331 to 333 are attached to the drive shaft 334 and rotate integrally with the drive shaft 334. An input gear is provided at one end of the drive shaft 334, and a driving force from a motor M, which is a drive source, is input to the input gear. The drive roller 302A is rotated by the driving force of the motor M. Each of the drive roller elements 331 to 333 is exposed to the conveying path CP through an opening formed in the conveying guide 316g.

[0050] Driven roller 302B includes driven roller elements 341, 342, and 343 as a plurality of second rotating components arranged in the sheet width direction Dw, and a driven shaft 344 as a shaft component supporting driven roller elements 341 to 343. Driven roller elements 341 to 343 are rotatably supported by driven shaft 344. Although driven roller elements 341 to 343 are rotatably mounted to driven shaft 344, they can rotate integrally with driven shaft 344. Each of driven roller elements 341 to 343 is exposed to the conveying path CP through an opening formed in the conveying guide 315g. Driven roller elements 341 to 343 are positioned corresponding to and in contact with drive roller elements 331 to 333.

[0051] The driven shaft 344 is rotatably supported by the transfer guide 315g on the side opposite to the transfer surface of the transfer guide 315g. The opening and closing cover 315 has, for example, ribs provided with shaft receiving portions that protrude in the height direction Dh from the surface of the transfer guide 315g opposite to the transfer surface and rotatably support both ends of the driven shaft 344.

[0052] The drive roller elements 331 to 333 and the driven roller elements 341 to 343 are rotating components (serving as rolling components, roller bodies) having an outer peripheral surface capable of contacting the original to be conveyed. The traction roller pair 302 is configured to clamp and convey the original using at least one of a plurality of clamping portions N1, N2, and N3 formed between the drive roller elements 331 to 333 and the driven roller elements 341 to 343.

[0053] According to this embodiment, drive roller 302A includes three drive roller elements 331 to 333, and driven roller 302B includes three driven roller elements 341 to 343. Drive roller element 331 is located at the center of the plurality of drive roller elements 331 to 333 in the sheet width direction Dw. Drive roller elements 332 and 333 are located at both ends of the plurality of drive roller elements 331 to 333 in the sheet width direction Dw. Similarly, driven roller element 341 is located at the center of the plurality of driven roller elements 341 to 343 in the sheet width direction Dw. Driven roller elements 342 and 343 are located at both ends of the plurality of driven roller elements 341 to 343 in the sheet width direction Dw.

[0054] According to this embodiment, the central drive roller element 331 and the central driven roller element 341 are arranged on the aforementioned conveying center Wc in the sheet width direction Dw. On the other hand, for at least a portion of the small-sized original that can be conveyed by the ADF 102, the drive roller elements 332 and 333 at both ends and the driven roller elements 342 and 343 at both ends are located outside the area through which the small-sized original passes in the sheet width direction Dw. In other words, the sheet width ratio of the smallest-sized original that can be conveyed by the ADF 102 (i.e., the sheet with the shortest length in the sheet width direction among the sheets that can be conveyed by the ADF 102) is the interval W1 from the driven roller element 342 adjacent to one side of the central driven roller element 341 to the driven roller element 343 adjacent to the other side of the central driven roller element 341. Figure 5 Therefore, at least some small-sized originals are held only by the centrally located clamping portion N1 of the three clamping portions N1 to N3 of the traction roller pair 302. Note that A4-sized originals are held by all three clamping portions N1 to N3.

[0055] The number of drive roller elements (serving as first rotating components) and driven roller elements (serving as second rotating components) included in drive roller 302A and driven roller 302B is not limited to three each. As described in the second embodiment below, the number can be four or five or more. When the number of driven roller elements is odd, the same construction as in this embodiment can be appropriately applied.

[0056] like Figure 5 and Figure 6A As shown, the driven roller retainer 320 (which serves as a retainer component, control component, and shaft receiving component) is attached to the driven shaft 344 of the driven roller 302B. Figure 6B As shown, the driven roller retainer 320 includes a first side surface portion 320a, a second side surface portion 320b, a base portion 320g, groove portions 320e and 320f, a protruding portion 320i, a rib portion 320r, shaft receiving holes 320c and 320d, and a spring receiving area 320h. The driven roller retainer 320 having the above portions can be integrally molded from resin material.

[0057] In the following text, the direction orthogonal to both the sheet width direction Dw and the sheet conveying direction Dc at the clamping portion of the traction roller pair 302 is referred to as the height direction Dh. The height direction Dh is the direction of a straight line connecting the rotation axis of the drive roller 302A and the rotation axis of the driven roller 302B. Furthermore, the direction in which the driven roller 302B is positioned relative to the drive roller 302A in the height direction Dh can be referred to as the "upper side in the height direction Dh", and the opposite direction can be referred to as the "lower side in the height direction Dh".

[0058] The base portion 320g has a plate-like shape extending in the sheet width direction Dw and the sheet conveying direction Dc. When viewed from above in the height direction Dh, the base portion 320g covers the driven roller element 341 at its center. The protruding portion 320i protrudes upward from the base portion 320g in the height direction Dh. The protruding portion 320i is a generally cylindrical or cylindrical protrusion for holding one end of the pressure spring 318. The spring receiving area 320h is the area in the base portion 320g surrounding the protruding portion 320i.

[0059] The first side surface portion 320a and the second side surface portion 320b extend downward along the height direction Dh from one end and the other end of the base portion 320g in the sheet width direction Dw, respectively. The first side surface portion 320a and the second side surface portion 320b extend along the sheet conveying direction Dc. The end face of the first side surface portion 320a facing the central driven roller element 341 in the sheet width direction Dw is ( Figure 6A The second side surface portion 320b faces the end face of the central driven roller element 341 on the other side in the sheet width direction Dw. The driven roller retainer 320 can control the position of the central driven roller element 341 in the sheet width direction Dw through the first side surface portion 320a and the second side surface portion 320b. The driven roller retainer 320 serves as a cover member that covers the drive roller 302A from the opposite side (upper side).

[0060] A shaft receiving hole 320c, serving as a first shaft receiving portion, is formed in a first side surface portion 320a, and a shaft receiving hole 320d, serving as a second shaft receiving portion, is formed in a second side surface portion 320b. The shaft receiving holes 320c and 320d are generally circular holes that penetrate the first side surface portion 320a and the second side surface portion 320b, respectively. The driven shaft 344 is inserted into the shaft receiving holes 320c and 320d. The first and second shaft receiving portions are not limited to through holes and may have, for example... Figure 6B A portion of the lower edge of the first side surface portion 320a and the second side surface portion 320b is recessed upward into a semi-circular concave shape.

[0061] The recessed portions 320e and 320f have a recessed shape that opens in a direction intersecting the sheet width direction Dw when viewed along the height direction Dh, and a recessed shape that extends along the height direction Dh. The recessed portions 320e and 320f are related to the two guide shapes 321a and 321b provided in the opening / closing cover 315. Figure 5The guided portions are joined together. Guide shapes 321a and 321b extend along a direction (preferably the height direction Dh) that intersects both the sheet width direction Dw and the sheet conveying direction Dc. Guide shapes 321a and 321b have a width approximately equal to (or slightly narrower than) the inner width of the recessed portions 320e and 320f in the sheet width direction Dw, and extend in the height direction Dh. Guide shapes 321a and 321b are integrally formed, for example, from a resin material with the conveying guide 315g.

[0062] The guided portion of the driven roller retainer 320 may be a protruding portion that extends upstream or downstream in the sheet conveying direction Dc. In this case, the guiding shape of the opening / closing cover 315 may be a concave shape that engages with the protruding portion or a groove shape that extends along the height direction Dh.

[0063] The driven roller retainer 320 is movable in the height direction Dh relative to the opening / closing cover 315. In other words, the driven roller retainer 320 is movable relative to the opening / closing cover 315 (second frame) to bring the rotation axis of the driven roller 302B closer to and move away from the rotation axis of the drive roller 302A. When the groove portions 320e and 320f engage with the guide shapes 321a and 321b, the position of the driven roller retainer 320 in the sheet width direction Dw is restricted.

[0064] Furthermore, the position of the driven roller retainer 320 in the sheet width direction Dw is controlled so that the position of the central driven roller element 341 controlled by the driven roller retainer 320 relative to the opening / closing cover 315 in the sheet width direction Dw is controlled. Therefore, for example, relative to other conveying rollers supported by the conveying guide 315g and the opening / closing cover 315, the positioning accuracy (alignment) of the driven roller element 341 at the center in the sheet width direction Dw can be improved.

[0065] In the case of small-sized originals, since the traction roller pair 302 only uses the central clamping portion N1 to hold the original, the original is more prone to rotation and skewed feed during transport compared to an A4-sized original held by multiple clamping portions N1 to N3. Because the positioning accuracy of the central driven roller element 341 is improved, skewed feed of the original can be reduced, especially when transporting small-sized originals, during transport by the traction roller pair 302.

[0066] The positions of the driven roller elements 342 and 343, other than the central driven roller element, in the sheet width direction Dw are limited, for example, by ribs provided on the opening / closing cover 315. The driven roller elements 342 and 343 can be positioned relative to the driven shaft 344 in the sheet width direction Dw.

[0067] According to this embodiment, two guide shapes 321a and 321b are arranged upstream and downstream of the driven roller holder 320 in the sheet conveying direction Dc. If one guide shape 321a is the first guide shape, the other guide shape 321b can be referred to as the second guide shape. Since the two guide shapes 321a and 321b face the bottoms of the recessed portions 320e and 320f, the position of the driven roller holder 320 in the sheet conveying direction Dc is restricted. By restricting the position of the driven roller holder 320, the positions of the driven shaft 344 and the driven roller elements 341 to 343 in the sheet conveying direction Dc are also restricted.

[0068] According to this embodiment, a groove portion 320e and a groove portion 320f are respectively provided on the upstream and downstream surfaces of the driven roller holder 320 in the sheet conveying direction Dc. Furthermore, according to this embodiment, the groove portions 320e and 320f, as well as the guide shapes 321a and 321b, are all provided on the conveying center Wc in the sheet width direction Dw. However, the position and number of the groove portions 320e and 320f can be changed.

[0069] Rib portion 320r is a protruding portion that protrudes from base portion 320g along the height direction Dh and extends along sheet width direction Dw between first side surface portion 320a and second side surface portion 320b. Although in Figure 6B Only the rib portion 320r provided at the upstream end of the sheet conveying direction Dc of the base portion 320g is shown, but a similar rib portion 320r is also provided at the downstream end of the base portion 320g. The rib portion 320r serves as a reinforcing rib, which can effectively transmit the spring force (pushing force) of the pressure spring 318 to the driven shaft 344 by increasing the stiffness of the driven roller retainer 320. The rib portion 320r is preferably formed continuously from the first side surface portion 320a to the second side surface portion 320b along the sheet width direction Dw.

[0070] Next, the pressure applied to the traction roller pair 302 by the pressure spring 318 will be described. Figure 4 and Figure 6A As shown, a pressure spring 318 is disposed between the opening / closing cover 315 and the driven roller holder 320, and presses the driven roller holder 320 downward along the height direction Dh. The driven roller holder 320 transmits the spring force of the pressure spring 318 to the driven shaft 344 by pressing the driven shaft 344 with the wall surfaces of the shaft receiving holes 320c and 320d. With this configuration, the driven roller elements 341 to 343 are pressed against the drive roller elements 331 to 333, and clamping pressure is generated in the clamping portions N1 to N3.

[0071] In other words, the spring force of the pressure spring 318 is transmitted to the driven shaft 344 that supports the plurality of driven roller elements 341 to 343. Therefore, the plurality of driven roller elements 341 to 343 (serving as a plurality of second rotating parts) can be pressed against the plurality of drive roller elements 331 to 333 (serving as a plurality of first rotating parts) by a pressure spring 318 (a pressure member).

[0072] The construction of the compression spring 318 will be described further. According to this embodiment, the compression spring 318, used as a pushing member, is a compression coil spring. However, a leaf spring or a rubber component can also be used as a pushing member.

[0073] The compression spring 318, acting as a compression coil spring, is configured such that its central axis is oriented along the height direction Dh. One end of the compression spring 318 in the height direction Dh contacts a spring receiving portion 322 disposed in the opening / closing cover 315, and the other end of the compression spring 318 contacts a spring receiving area 320h of the driven roller retainer 320. The spring receiving area 320h is the pressed area of ​​the driven roller retainer 320 that receives force from the compression spring 318. The spring receiving portion 322 of the opening / closing cover 315 is disposed, for example, on a bracket 315A fixed to the conveying guide 315g with screws or the like. The spring receiving portion 322 may be integrally formed with other parts of the opening / closing cover 315. The bracket 315A includes a protrusion 323 to which the compression spring 318 can be attached by pressing one end of the compression spring 318 onto the protrusion.

[0074] A compression spring 318 is disposed at the conveying center Wc in the sheet width direction Dw. In other words, a portion of the compression spring 318 exists at the conveying center Wc in the sheet width direction Dw. Preferably, the position of the central axis of the compression spring 318, which is a compression helical spring, in the sheet width direction Dw is configured to coincide with the conveying center Wc, except for unavoidable errors such as assembly tolerances.

[0075] According to this embodiment, the pressure spring 318 is the only pressing member that pushes the drive roller 302A or the driven roller 302B to press the plurality of drive roller elements 331 and the plurality of driven roller elements 341 into contact with each other. Apart from the pressure spring 318, no other pressing member is provided for pushing the driven roller 302B toward the drive roller 302A. Furthermore, no other pressing member is provided for pushing the drive roller 302A toward the driven roller 302B. In other words, the pressure spring 318 is the only pressing member that pushes the drive roller or the driven roller to press the plurality of first rotating parts and the plurality of second rotating parts into contact with each other.

[0076] According to this embodiment, multiple clamping portions N1 to N3 can be pressed using a simple construction employing a single pressure spring 318 (used as a pressing component).

[0077] Summary of this embodiment

[0078] According to this embodiment, a plurality of driven roller elements 341 to 343 (serving as a plurality of second rotating components) are pressed against a plurality of drive roller elements 331 to 333 (serving as a plurality of first rotating components) by the spring force of a pressure spring 318 (serving as a pressing component). In the driven roller holder 320, the first side surface portion 320a and the second side surface portion 320b control the position of the central driven roller element 341 (serving as a central second rotating component) in the sheet width direction Dw. Furthermore, the driven roller holder 320 transmits the spring force of the pressure spring 318 to the driven shaft 344 (serving as a shaft component) via shaft receiving holes 320c and 320d (first shaft receiving portion and second shaft receiving portion) of the first side surface portion 320a and the second side surface portion 320b.

[0079] According to the above structure, the spring force of the pressure spring 318 is transmitted from the first side surface portions 320a and 320b near the central driven roller element 341 to the driven shaft 344. Therefore, the central driven roller element 341 can press against the drive roller elements 331 to 333 more forcefully than the other driven roller elements 342 and 343. Therefore, the clamping pressure in the central clamping portion N1 can be increased, and the force applied by the central drive roller element 331 and the driven roller element 341 to the sheet transport direction Dc of the original can be further increased. Thus, when the ADF 102 is transporting small-sized originals, even if the traction roller pair 302 only clamps the original by the central clamping portion N1, the traction roller pair 302 can overcome the frictional resistance borne by the original at the separation portion Ns and feed the original.

[0080] In other words, according to this embodiment, a sheet conveying device capable of more stably conveying small-sized sheets can be provided. According to this embodiment, an image reading device 101 capable of more stably conveying small-sized originals can be provided.

[0081] Note that the above description describes the case where a small original is held by only the central clamping portion N1 of 302 using the traction rollers. However, a similar effect can be achieved for small originals held by a portion of the clamping portions N2 and N3 (excluding the central portion) holding their side ends. In other words, even if the sheet width is slightly larger than the interval W1 between the clamping portions N2 and N3 in the sheet width direction Dw, the effect is similar. Figure 6A In the case of small-sized originals, the conveying force applied to the original by the traction roller 302 at the clamping portions N2 and N3 is also relatively small. Therefore, when the conveying force applied to the original by the traction roller 302 at the central clamping portion N1 is relatively small, the stability of original conveying may decrease. According to this embodiment, the original can be conveyed stably even under such conditions.

[0082] Here, as a method to increase the transmission force in the central clamping portion N1, a configuration of arranging two pressure springs near both ends of the central driven roller element 341 can be considered (hereinafter referred to as the comparative example). However, in this configuration, the point of application of the spring force of the pressure spring is located slightly away from the transmission center Wc, in order to ensure space for attaching the pressure spring, and therefore it is difficult to concentrate the pressing force on the central clamping portion N1. Here, concentrating the pressing force on the central clamping portion N1 means increasing the ratio of the pressing force in the central clamping portion N1 to the pressing force in the clamping portions N2 and N3 at both ends.

[0083] On the other hand, according to this embodiment, the spring force is transmitted from the first side surface portion 320a and the second side surface portion 320b of the driven roller holder 320, in which the central driven roller element 341 is located, to the driven shaft 344. Therefore, compared with the comparative example described above, the points of application of the spring force of the pressure spring 318 relative to the driven shaft 344, p1 and p2, can be made more effective. Figure 6A The document is located near the transfer center Wc. Therefore, according to this embodiment, the pressing pressure can be more concentrated on the central clamping part N1, and small-sized originals can be transferred more stably.

[0084] More specifically, the pressing force in the central clamping portion N1 is preferably greater than the pressing force in any of the clamping portions other than the central clamping portion N1 (i.e., clamping portions N2 and N3 according to this embodiment). However, the pressing force in the clamping portion N1 is the magnitude of the force by which the drive roller element 331 and the driven roller element 341 press against each other in the height direction Dh, and corresponds to the force obtained by integrating the clamping pressure over the entire contact surface between the drive roller element 331 and the driven roller element 341.

[0085] Furthermore, the pressing force at the central clamping part N1 can be configured to be greater than the sum of the pressing forces at all clamping parts N2 and N3 other than the central clamping part N1.

[0086] In the comparative example, due to manufacturing tolerances of the two pressure springs, the distribution of pressing force in the clamping portions N1 to N3 of the traction roller pair 302 may become asymmetrical relative to the conveying center Wc (hereinafter referred to as the left-right difference in clamping force). For example, if the pressing force in the clamping portion N2 on one end side is greater than the pressing force in the clamping portion N3 on the other end side, the original may rotate and skew when the traction roller pair 302 conveys an A4-sized original. On the other hand, according to this embodiment, the multiple clamping portions N1 to N3 are pressed by the spring force of a single pressure spring 318 via the driven roller holder 320 and the driven shaft 344. Therefore, the left-right difference in clamping force due to manufacturing tolerances of the pressure springs can be avoided.

[0087] Second Embodiment

[0088] A second embodiment will be described, wherein the arrangement of the driven roller elements differs from that of the first embodiment. Hereinafter, unless otherwise stated, it is assumed that elements denoted by the same reference numerals as those in the first embodiment have substantially the same construction and operation as those described in the first embodiment, and the differences from the first embodiment will be primarily described. When the number of driven roller elements is even, the same construction as in this embodiment can be appropriately applied.

[0089] Figure 7 This is a cross-sectional view showing the cross-section of the ADF 102 according to this embodiment, and it corresponds to the first embodiment. Figure 6A The view. For example... Figure 7 As shown, according to this embodiment, the drive roller 302A includes four drive roller elements 351 to 354 as a plurality of first rotating components, and a drive shaft 355 supporting the drive roller elements 351 to 354. The driven roller 302B includes four driven roller elements 361 to 364 as a plurality of second rotating components, and a driven shaft 365 (serving as a shaft component) supporting the driven roller elements 361 to 364. Each of the drive roller elements 351 to 354 contacts the driven roller elements 361 to 364 to form four clamping portions.

[0090] Two driven roller elements 361 and 362 (serving as two second rotating components) in the central portion are located between driven roller elements 363 and 364 at both ends in the sheet width direction Dw. Unlike the first embodiment, the two driven roller elements 361 and 362 in the central portion are both located away from the conveying center Wc and are adjacent to each other with the conveying center Wc in between.

[0091] The driven roller retainer 370 (which serves as a retainer component, control component, and shaft receiving component) is attached to the driven shaft 365 of the driven roller 302B. The driven roller retainer 370 is configured to control the position of the two driven roller elements 361 and 362 at the central portion in the sheet width direction Dw, and to transmit the spring force of the pressure spring 318 to the driven shaft 344.

[0092] Specifically, the driven roller retainer 370 according to this embodiment includes a first side surface portion 370a, a second side surface portion 370b, a third side surface portion 370c, and a fourth side surface portion 370d. The first side surface portion 370a faces the outer end face of the driven roller element 361 in the sheet width direction Dw. The second side surface portion 370b faces the outer end face of the driven roller element 362 in the sheet width direction Dw. The third side surface portion 370c faces the inner end face of the driven roller element 361 in the sheet width direction Dw. The fourth side surface portion 370d faces the inner end face of the driven roller element 362 in the sheet width direction Dw. The positions of the two driven roller elements 361 and 362 at the central portion in the sheet width direction Dw are limited by the first side surface portion 370a to the fourth side surface portion 370d.

[0093] A shaft receiving hole (first shaft receiving portion) for inserting the driven shaft 365 is formed in the first side surface portion 370a. Similarly, shaft receiving holes (second shaft receiving portion, third shaft receiving portion, and fourth shaft receiving portion) for inserting the driven shaft 365 are formed in the second side surface portion 370b, the third side surface portion 370c, and the fourth side surface portion 370d. When the shaft receiving hole abuts against the driven shaft 365, the spring force of the compression spring 318 is transmitted.

[0094] According to this embodiment, the sheet width of the smallest original document that can be conveyed by the ADF 102 (i.e., the sheet with the shortest length along the sheet width direction among the sheets that can be conveyed by the ADF 102) is shorter than the interval from the driven roller element 363 adjacent to one side of the two driven roller elements 361 and 362 at the central portion to the driven roller element 364 adjacent to the other side. Therefore, at least some small-sized original documents are held only by the two clamping portions located at the central portion of the four clamping portions included in the traction roller pair 302. Note that A4-sized original documents are held by all four clamping portions.

[0095] Similarly, according to this embodiment, a plurality of driven roller elements 361 to 364 (serving as a plurality of second rotating parts) are pressed against a plurality of drive roller elements 351 to 354 (serving as a plurality of first rotating parts) by the spring force of a pressure spring 318 (serving as a pushing member). A driven roller retainer 370 controls the position of two driven roller elements 361 and 262 (serving as two second rotating parts) at the central portion in the sheet width direction Dw via a first side surface portion 370a and a second side surface portion 370b. Furthermore, the driven roller retainer 370 transmits the spring force of the pressure spring 318 to the driven shaft 365 (serving as a shaft member) via shaft receiving holes (serving as a first shaft receiving portion and a second shaft receiving portion) in the first side surface portion 370a and the second side surface portion 370b.

[0096] Based on the above construction, similar to the first embodiment, the pressing force of the two driven roller elements 361 and 362 in the central portion can be stronger than the pressing force of the other driven roller elements 363 and 364. Therefore, similar to the first embodiment, this embodiment provides a sheet conveying device capable of more stably conveying small-sized sheets. According to this embodiment, an image reading device 101 capable of more stably conveying small-sized originals can be provided.

[0097] Other embodiments

[0098] In the various embodiments described above, examples of applying this technology to the ADF 102 (i.e., a sheet transport device for conveying originals in the image reading device 101) have been described. This technology is not limited thereto and can be applied, for example, to a sheet transport device for conveying sheets used as recording material in an image forming apparatus.

[0099] According to this disclosure, a sheet conveying device that can convey small-sized sheets more stably can be provided.

[0100] Although the invention has been described with reference to exemplary embodiments, it should be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the appended claims should be accorded the broadest interpretation so as to cover all such variations and equivalent structures and functions.

Claims

1. A sheet conveying device, comprising: A conveying component configured to convey sheets; A separating component, configured to form a separating section together with the conveying component and to separate sheets one by one in the separating section; A drive roller is disposed downstream of the separating section in the sheet conveying direction, and the drive roller includes a plurality of first rotating components arranged in the sheet width direction orthogonal to the sheet conveying direction. A motor configured to drive the drive roller; A driven roller configured to rotate following the drive roller includes a plurality of second rotating components that are in contact with the plurality of first rotating components and a shaft component that supports the plurality of second rotating components; A retainer component configured to control the position of a central second rotating component disposed at the center in the width direction of the sheet among a plurality of second rotating components; as well as A push spring, configured to push against the retainer component, such that the plurality of second rotating components press against the plurality of first rotating components. The retainer component includes: (i) a first side surface portion facing the end face of the central second rotating component on one side of the sheet width direction and having a first shaft receiving portion for receiving the shaft component; and (ii) a second side surface portion facing the end face of the central second rotating component on the other side of the sheet width direction and having a second shaft receiving portion for receiving the shaft component. The retainer component is configured to control the position of the central second rotating component in the sheet width direction via the first side surface portion and the second side surface portion, and to apply the pushing force of the push spring to the shaft component via the first shaft receiving portion and the second shaft receiving portion.

2. The sheet conveying device according to claim 1, The push spring is the only push spring that pushes the driven roller to press the plurality of first rotating parts and the plurality of second rotating parts into contact with each other.

3. The sheet conveying device according to claim 1, The central second rotating component, the retainer component, and the push spring are disposed at the center of the conveying path traversed by the sheet in the width direction of the sheet.

4. The sheet conveying device according to any one of claims 1 to 3, The pressing force in the central clamping portion of the plurality of clamping portions formed by the plurality of first rotating components and the plurality of second rotating components is greater than the pressing force in any other clamping portion of the plurality of clamping portions except the central clamping portion.

5. The sheet conveying device according to claim 4, The pressing force in the central clamping portion is greater than the sum of the pressing forces in all clamping portions other than the central clamping portion.

6. The sheet conveying device according to any one of claims 1 to 3, further comprising: A first frame, the first frame including a first guide portion configured to form a conveying path for the sheet, the first frame supporting the drive roller; as well as A second frame, including a second guide portion configured to form the transmission path together with the first guide portion, is movable relative to the first frame to open the transmission path. The retainer component is supported by the second frame and is movable relative to the second frame, such that the rotation axis of the driven roller approaches and moves away from the rotation axis of the drive roller.

7. The sheet conveying device according to claim 6, The second frame has a guide shape that extends in a direction intersecting both the sheet conveying direction and the sheet width direction. The retainer component includes a guided portion that engages with the guide shape, and The position of the retainer component in the width direction of the sheet is controlled by the engagement between the guide shape and the guided portion.

8. The sheet conveying device according to claim 7, The guide shape is positioned upstream of the retainer component in the sheet conveying direction. The second frame further includes a second guide shape, which is positioned downstream of the retainer component in the sheet conveying direction. The position of the retainer component in the sheet conveying direction is controlled by the guide shape and the second guide shape.

9. The sheet conveying device according to any one of claims 1 to 3, The retainer component includes a base portion extending in the width direction of the sheet. The first side surface portion and the second side surface portion extend from one end and the other end of the base portion in the sheet width direction, respectively, toward a direction intersecting both the sheet width direction and the sheet conveying direction. The base portion is provided with a pressing area to receive the pushing force of the push spring.

10. The sheet conveying device according to claim 9, The retainer component further includes a rib portion that protrudes from the base portion and is formed to extend along the width direction of the sheet between the first side surface portion and the second side surface portion.

11. The sheet conveying device according to any one of claims 1 to 3, Among the sheets that can be conveyed by the sheet conveying device, the sheet with the shortest length in the sheet width direction has a length in the sheet width direction shorter than the interval in the sheet width direction from one of the plurality of second rotating parts adjacent to one side of the central second rotating part to another of the plurality of second rotating parts adjacent to the other side of the central second rotating part.

12. An image reading device, comprising: The sheet conveying apparatus according to any one of claims 1 to 11; as well as A reading unit configured to read images from a sheet conveyed by the sheet conveying device.

13. An image forming apparatus comprising: The image reading device according to claim 12; as well as An image forming portion, configured to form an image on a recording material. The image forming apparatus is configured to form the image on a recording material based on image information acquired by the image reading device.

14. A sheet conveying device, comprising: A conveying component configured to convey sheets; A separating component, configured to form a separating section together with the conveying component and to separate sheets one by one in the separating section; A drive roller is disposed downstream of the separating section in the sheet conveying direction, and the drive roller includes a plurality of first rotating components arranged in the sheet width direction orthogonal to the sheet conveying direction. A motor configured to drive the drive roller; A driven roller configured to rotate following the drive roller includes a plurality of second rotating components that are in contact with the plurality of first rotating components and a shaft component that supports the plurality of second rotating components; A retainer component, the retainer component being configured to control the position of two second rotating components disposed at a central portion in the width direction of the sheet among the plurality of second rotating components; as well as A push spring, configured to push against the retainer component, such that the plurality of second rotating components press against the plurality of first rotating components. The retainer component includes: (i) a first side surface portion facing one of the two second rotating components in the sheet width direction and having a first shaft receiving portion for receiving the shaft component; and (ii) a second side surface portion facing the other of the two second rotating components in the sheet width direction and having a second shaft receiving portion for receiving the shaft component. The retainer component is configured to control the position of the two second rotating components in the sheet width direction via the first side surface portion and the second side surface portion, and to apply the pushing force of the push spring to the shaft component via the first shaft receiving portion and the second shaft receiving portion.

15. The sheet conveying device according to claim 14, The push spring is the only push spring that pushes the driven roller to press the plurality of first rotating parts and the plurality of second rotating parts into contact with each other.

16. The sheet conveying device according to claim 14 or 15, The two second rotating components are positioned adjacent to each other at the center of the conveying path of the conveying sheet in the width direction of the sheet, and The retainer component and the push spring are disposed at the center of the conveying path in the width direction of the sheet.

17. The sheet conveying device according to claim 14 or 15, Among the sheets that can be conveyed by the sheet conveying device, the sheet with the shortest length in the sheet width direction has a length in the sheet width direction shorter than the interval in the sheet width direction from one of the plurality of second rotating parts adjacent to one side of the two second rotating parts to another of the plurality of second rotating parts adjacent to the other side of the two second rotating parts.

18. A sheet conveying device, comprising: A conveying component configured to convey sheets; A separating component, configured to form a separating section together with the conveying component and to separate sheets one by one in the separating section; A drive roller is disposed downstream of the separating section in the sheet conveying direction, and the drive roller includes a plurality of first rotating components arranged in the sheet width direction orthogonal to the sheet conveying direction. A motor configured to drive the drive roller; A driven roller configured to rotate following the drive roller includes a plurality of second rotating components that are in contact with the plurality of first rotating components and a shaft component that supports the plurality of second rotating components; A retainer component, the retainer component being configured to cover the central second rotating component of the plurality of second rotating components located at the center in the width direction of the sheet from the side opposite to the drive roller; as well as A push spring, configured to push against the retainer component, such that the plurality of second rotating components press against the plurality of first rotating components. The push spring is the only push spring that pushes the driven roller to press the plurality of first rotating parts and the plurality of second rotating parts into contact with each other.

19. The sheet conveying device according to claim 18, The retainer component includes: (i) a first side surface portion, the first side surface portion facing the end face of the central second rotating member on one side in the sheet width direction and having a first shaft receiving portion for receiving the shaft member, and (ii) a second side surface portion, the second side surface portion facing the end face of the central second rotating member on the other side in the sheet width direction and having a second shaft receiving portion for receiving the shaft member, and The retainer component is configured to apply the pushing force of the push spring to the shaft component via the first shaft receiving portion and the second shaft receiving portion.

20. The sheet conveying device according to claim 19, The retainer component includes a base portion extending in the width direction of the sheet. The first side surface portion and the second side surface portion extend from one end and the other end of the base portion in the sheet width direction, respectively, toward a direction intersecting both the sheet width direction and the sheet conveying direction. The base portion is provided with a pressing area to receive the pushing force of the push spring.

Images