JP5933477B2 - Sheet conveying apparatus, image reading apparatus, and image forming apparatus - Google Patents

Description

  The present invention relates to a sheet conveying apparatus that conveys a sheet placed on a sheet placing unit, and in particular, regulates an end portion of a sheet placed on the sheet placing unit at a transport position that can be transported by a transport unit. The present invention relates to a sheet conveying apparatus having a regulation unit, an image reading apparatus including the sheet conveying apparatus, and an image forming apparatus.

  An image reading apparatus such as a scanner is provided with an automatic document feeder (hereinafter referred to as “ADF”) that automatically conveys a sheet set on a feeding tray. The sheet set in the paper feed tray is conveyed to the reading position by the ADF, and then discharged to the discharge tray. In this conveyance process, the image of the sheet is read at the reading position. This type of ADF is provided with a stopper for aligning the leading edge of the sheet set on the feeding tray or preventing the sheet from being inserted into the back side of the ADF from a predetermined position (Patent Literature). 1).

JP 2011-213447 A

  However, the stopper described in Patent Document 1 is locked so that it cannot be displaced by a lever or the like when the pickup roller is in the standby position. Therefore, when a bundle of sheets is set on the feeding tray and is strongly inserted into the inside of the ADF, there is a problem that the leading end of the sheet bundle strongly presses the stopper and the stopper is damaged.

  The present invention has been made in view of the above circumstances, and the purpose of the present invention is to control the restriction portion by the external force even when an external force is applied such as when the sheet is placed on the sheet placement portion and strongly inserted. An object of the present invention is to provide a sheet conveying apparatus capable of preventing breakage, an image reading apparatus including the sheet conveying apparatus, and an image forming apparatus.

The present invention is a sheet conveying apparatus including a sheet placing unit, a conveying unit, a regulating unit, a movable unit, and a holding unit. A sheet is placed on the sheet placing portion. The conveying unit conveys the sheet placed on the sheet placing unit to the inside of the apparatus main body. The restricting portion restricts an end portion of the sheet placed on the sheet placing portion in the conveying direction by the conveying unit at a conveying position that can be conveyed by the conveying unit, and contrary to the restriction at the conveying position, the sheet Is moved in the transport direction from the transport position in the transport direction. The movable portion is changeable in posture between a first posture covering a part of the apparatus main body and a second posture separated from the first posture. The holding unit holds the movable unit in the first posture, and releases the holding of the movable unit when the regulating unit is displaced in the transport direction.
In addition, the present invention is configured as an image reading apparatus including the above-described sheet conveying apparatus or an image forming apparatus including the above-described sheet conveying apparatus.

  According to the present invention, even when an external force is applied, for example, when a sheet is placed on the sheet placement portion and is strongly inserted in the conveyance direction of the sheet, the restriction portion is prevented from being damaged by the external force. Is possible.

FIG. 1 is a perspective view illustrating a schematic configuration of a sheet conveying apparatus according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the sheet conveying apparatus according to the embodiment of the present invention. FIG. 3 is a partial cross-sectional view showing a cross-sectional structure taken along section line III-III in FIG. FIG. 4 is a perspective view showing the configuration of the holding unit according to the embodiment of the present invention. FIG. 5 is a partial cross-sectional view showing a cross-sectional structure taken along a cutting line VV in FIG. FIG. 6 is a schematic diagram showing the configuration of the drive transmission mechanism according to the embodiment of the present invention. FIG. 7 is a partial cross-sectional view for explaining operations of the pickup roller and the stopper according to the embodiment of the present invention. FIG. 8 is a partial cross-sectional view for explaining the operation of the stopper and the cover according to the embodiment of the present invention. FIG. 9 is a schematic diagram showing a schematic configuration of an image reading apparatus according to another embodiment of the present invention. FIG. 10 is a schematic diagram showing a schematic configuration of an image forming apparatus according to another embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings as appropriate. The embodiment described below is merely an example embodying the present invention, and the embodiment of the present invention can be changed as appropriate without departing from the scope of the present invention.

  FIG. 1 is a perspective view showing a schematic configuration of an automatic document feeder 10 (hereinafter referred to as “ADF 10”) according to an embodiment of the present invention. The ADF 10 is an example of a sheet conveying apparatus of the present invention, and is used by being mounted on an image reading apparatus or an image forming apparatus. The ADF 10 picks up the documents 26 one by one at a predetermined reading position and automatically conveys them sequentially. The image reading apparatus equipped with the ADF 10 reads an image of the document 26 being conveyed by the ADF 10 at the reading position. Further, the image forming apparatus equipped with the ADF 10 forms an image on the printing paper based on the image of the document 26 read during conveyance by the ADF 10.

  The ADF 10 conveys the document 26 (an example of the sheet of the present invention) along a conveyance path 37 (see FIG. 2, an example of the sheet conveyance path of the present invention). As shown in FIG. 1, the ADF 10 includes a main body 11 (an example of the apparatus main body of the present invention), a cover 13 (an example of the movable part of the present invention), and a feeding tray 12 (the sheet mounting portion of the present invention. An example) 12 and a discharge tray 14 are provided. The main body 11 constitutes a housing of the ADF 10. A plurality of components constituting the ADF 10 are provided inside the main body 11. The feeding tray 12 is a portion on which the document 26 conveyed by the ADF 10 is placed, and is formed in a flat tray shape. As shown in FIG. 1B, a plurality of documents 26 are placed on the feeding tray 12 in a bundled state. The discharge tray 14 is provided below the feeding tray 12. That is, the feeding tray 12 and the discharge tray 14 are provided in a two-stage configuration.

  The cover 13 is an example of a movable part of the present invention, and includes a closed posture (corresponding to the first posture of the present invention) covering a part of the main body 11 and an open posture (upward of the present invention) separated from the closed posture. (Equivalent to the second posture). Specifically, the cover 13 is rotatably supported by a support shaft 20 provided in the main body 11. The cover 13 opens and closes the conveyance path 37. When the cover 13 is in the closed position, a part of the conveyance path 37 is covered. When the cover 13 is in the open position, a part of the transport path 37 is opened. In the present embodiment, as shown in FIG. 2, the support shaft 20 is provided on the side surface opposite to the feeding tray 12 side (the left side surface in FIG. 2), and the cover 13 is centered on the support shaft 20. , The feed tray 12 side of the cover 13 opens and closes in the vertical direction indicated by the double arrow 22. Further, the support shaft 20 is provided with a torsion coil spring (not shown). This torsion coil spring applies an elastic biasing force in a direction in which the cover 13 is rotated from the closed position to the open position.

  An operation lever 47 (an example of the operation lever of the present invention) is provided on the upper surface of the main body 11. The operation lever 47 is used when the cover 13 is rotated from the locked state in which the cover 13 is maintained in the closed position by a lock by a lock member 64 (an example of the holding portion of the present invention) described later to the open position. The locked state by the lock member 64 is released. Specifically, the operation lever 47 is connected to a support shaft 65 of a lock member 64 (described later) provided in the main body 11, and is supported to be rotatable about the support shaft 65. In the present embodiment, the operation lever 47 is supported so as to be lifted from the upper surface of the main body 11, and the support shaft 65 rotates when the operation lever 47 is pulled up.

  A lock member 64 shown in FIG. 3 is provided inside the main body 11. The lock member 64 holds the cover 13 in the closed position. As shown in FIG. 4, the column-shaped support shaft 65 and the hook-shaped portion 66 provided at one end of the support shaft 65. And a protruding portion 67 provided on the opposite side of the shaft 65 from the hook-shaped portion 66. Both the hook-shaped portion 66 and the protruding portion 67 are members protruding in a direction perpendicular to the support shaft 65, but the protruding portion 67 protrudes in a direction perpendicular to the protruding direction of the hook-shaped portion 66. Yes. Further, as shown in FIG. 3, a latching portion 70 on which the hook-like portion 66 is hooked is provided inside the main body 11. The latching part 70 is provided in the internal frame of the main body 11, for example. In the present embodiment, the hook 13 of the lock member 64 is hooked on the hook portion 70, whereby the cover 13 is locked and held in the closed position (see FIG. 3A). When the operating lever 47 provided on the cover 13 is pulled up, the support shaft 65 of the lock member 64 rotates in conjunction with the pulling operation. Thereby, the hook-shaped part 66 leaves | separates from the latching part 70, and latching of the hook-shaped part 66 and the latching part 70 is cancelled | released (refer FIG.3 (B)). That is, the locked state in which the cover 13 is maintained in the closed position is released, and the cover 13 can be rotated from the closed position to the open position as shown in FIG. At this time, the cover 13 rotates upward against its own weight by the urging force of the torsion coil spring provided on the support shaft 20.

  As shown in FIG. 2, the conveyance path 37 is formed inside the main body 11. The conveyance path 37 connects the feeding tray 12 and the discharge tray 14. The conveyance path 37 is partitioned by a plurality of conveyance guides 31 to 34 provided inside the main body 11. The ADF 10 includes a feeding mechanism 40 (an example of a transport unit according to the present invention) and a transport roller 42 along the transport path 37.

  The feeding mechanism 40 is provided in the vicinity of a chute portion 49 that is a connection portion between the feeding tray 12 and the conveyance path 37 of the ADF 10. The feeding mechanism 40 conveys the sheet placed on the feeding tray 12 to the inside of the main body 11. The feeding mechanism 40 is attached to the back side of the cover 13. As shown in FIG. 5, the feeding mechanism 40 includes a drive shaft 73 (an example of the drive shaft of the present invention), a pickup roller 79, a feed roller 80, and a frame 82 that supports these. . The frame 82 is rotatably supported on the drive shaft 73. Specifically, the end of the frame 82 on the main body 11 side is supported by the drive shaft 73. A pickup roller 79 is rotatably supported at the end of the frame 82 on the feeding tray 12 side. The frame 82 is urged toward the cover 13 by an elastic member such as a coil spring, for example. Therefore, in a state where no external force is applied, the frame 82 stands by at a standby position away from the feeding tray 12 as shown in FIG.

  The drive shaft 73 transmits a rotational drive force output from a drive source such as a motor. A feed roller 80 is connected to the drive shaft 73. Therefore, when the drive shaft 73 is driven to rotate, the feeding roller 80 also rotates. When the drive shaft 73 is driven to rotate, a force in the same direction as the rotation direction of the drive shaft 73 is applied to the frame 82 by a fixed holding force (for example, a torque limiter) between the frame 82 and the drive shaft 73. The For this reason, as shown in FIG. 6A, when the drive shaft 73 is driven to rotate in the clockwise direction, the frame 82 rotates about the drive shaft 73 in the clockwise direction. As a result, the frame 82 moves against the document 26 on the feeding tray 12 from the standby position with the drive shaft 73 as the center, as shown in FIG. 7, against the biasing force of the coil spring. It rotates to the contact position where it contacts.

  Further, as shown in FIG. 6, the feeding mechanism 40 includes a first transmission unit 75 (see FIG. 6B, an example of the first transmission unit of the present invention) and a second transmission unit 77 (see FIG. C), an example of the second transmission portion of the present invention) and a regulating member 90 (see FIG. 6A, an example of the regulating portion of the present invention). In the present embodiment, the restriction member 90 is disposed on the foremost side of the paper surface of FIG. 6, the first transmission part 75 is disposed on the back side of the restriction member 90, and the second transmission part is disposed on the back side of the first transmission part 75. 77 is arranged.

  The first transmission unit 75 transmits the rotational driving force of the drive shaft 73 to the pickup roller 79. Specifically, as shown in FIG. 6B, the first transmission unit 75 is connected to the input gear 87 connected to the drive shaft 73, the three intermediate gears 88A to 88C, and the pickup roller 79. Output gear 89. Each gear meshes sequentially. Therefore, when the drive shaft 73 is rotationally driven in the clockwise direction in FIG. 6B, the rotational driving force is transmitted to the input gear 87, and thereafter, via the intermediate gears 88A to 88C and the output gear 89. To the pickup roller 79. As a result, the pickup roller 79 rotates in the same direction as the feeding roller 80, that is, in a direction in which the document 26 can be fed from the feeding tray 12.

  The regulating member 90 regulates the leading end portion 26 </ b> A at a feeding position where the leading end portion 26 </ b> A of the document 26 placed on the feeding tray 12 can be fed by the pickup roller 79. When the rotational driving force in the clockwise direction is transmitted to the drive shaft 73 and the pickup roller 79 is rotated by the first transmission unit 75 in a state where the frame 82 is in the contact position, the regulating member 90 is moved to a later-described first member. 2 The force from the transmission part 77 is received and lifted upward (see FIG. 7). On the other hand, in the state where the rotational driving force is not transmitted to the drive shaft 73, the frame 82 is in the standby position and does not receive a force from the second transmission portion 77 described later. It is lowered to a position where it can contact the leading end 26A of the placed document 26 (see FIG. 5).

  In the present embodiment, the restricting member 90 moves from the state in which the tip end portion 26 </ b> A is restricted by the restricting member 90 at the feeding position, and the tip end portion 26 </ b> A moves from the feeding position to the pickup roller 79 against the restriction by the restricting member 90. Is moved downstream from the feeding position in the feeding direction. For example, when the document 26 is placed on the feeding tray 12 and the document 26 is further pushed in the feeding direction from the state where the leading end portion 26A is in contact with the regulating member 90 and regulated, the leading edge of the document 26 is placed. Upon receiving a pressing force of a predetermined value or more in the feeding direction from the portion 26A, the regulating member 90 is displaced from the feeding position to the downstream side in the feeding direction. Specifically, as shown in FIG. 6A, the regulating member 90 includes a rotating body 92 that is rotatably supported by the frame 82, and a stopper 93 that is rotatably supported by the rotating body 92. Is provided. The rotating body 92 includes a support shaft 95 supported by the frame 82, a base portion 96 extending from the support shaft 95 toward the main body 11, and an arm 97 extending downward from the base portion 96 and rotatably supporting the stopper 93. Further, an elastic member such as a torsion coil spring is provided on the support shaft 95 of the rotating body 92, and in FIG. 6, the rotating body 92 is urged in the counterclockwise direction by the predetermined value. The stopper 93 includes a support portion 98 that is rotatably supported by the arm 97, an upper contact portion 99 that extends upward from the support portion 98 and contacts the protruding portion 67 of the lock member 64, and extends downward from the support portion 98. And a lower abutting portion 94 that abuts on the leading end portion 26A of the document 26. The lower contact portion 94 reaches the placement surface of the feeding tray 12 when the drive shaft 73 is not rotationally driven and the frame 82 is in the standby position. Therefore, when the document 26 is placed on the feeding tray 12 in a state where the drive shaft 73 is not rotationally driven, the leading end portion 26A is restricted by the lower contact portion 94 of the stopper 93 as shown in FIG. Is done.

  The second transmission unit 77 transmits the rotational driving force of the drive shaft 73 to the regulating member 90 and moves the regulating member 90 in a direction away from the feeding tray 12. Specifically, as shown in FIG. 6C, the second transmission portion 77 is coaxially connected to the intermediate gear 100A meshed with the input gear 87, the intermediate gear 100A, and a torque limiter (not shown). The intermediate gear 100B pivotally supported by the intermediate gear 100B and the fan-shaped rack gear 101 meshed with the intermediate gear 100B are provided. In FIG. 6C, the intermediate gear 100B and the intermediate gear 100B are shown as being overlapped because they are arranged in a direction perpendicular to the paper surface. The rack gear 101 is coupled to the support shaft 95 of the restriction member 90. The intermediate gear 100B meshes with the rack gear 101. Therefore, when the drive shaft 73 is rotationally driven in the clockwise direction in FIG. 6C, the rotational driving force is transmitted to the input gear 87, and thereafter, the intermediate gear 100A, a torque limiter (not shown), and It is transmitted to the rack gear 101 via the intermediate gear 100B. When the rack gear 101 is rotated in the clockwise direction, the rotational force is transmitted to the rotating body 92 of the restricting member 90 via the support shaft 95. As a result, as shown in FIG. 7, the rotating body 92 is rotated in the clockwise direction, and the stopper 93 is lifted upward.

  When the rotational driving force from the input gear 87 is continuously transmitted and the rack gear 101 rotates in the clockwise direction, the rack gear 101 comes into contact with the contact member 102 provided in the rotational direction. Thereby, the further rotation of the rack gear 101 is restricted by the contact member 102. At this time, torque exceeding the set torque is applied to the torque limiter provided between the intermediate gear 100A and the intermediate gear 100B, and the driving force from the intermediate gear 100A to the intermediate gear 100B is not transmitted. That is, after the rack gear 101 contacts the contact member 102, the rotational driving force to the rack gear 101 is interrupted.

  In the ADF 10 of the present embodiment, the document 26 is placed on the feeding tray 12 when the frame 82 is in the standby position shown in FIG. At this time, a plurality of bundles of originals 26 are placed on the feeding tray 12, and the originals 26 are inserted into the chute unit 49, so that the leading end of the originals 26 comes into contact with the lower contact part 94 of the stopper 93. If the pressing force when the document 26 contacts the lower contact portion 94 is less than the predetermined value, the leading end portion 26A of the document 26 is regulated by the lower contact portion 94. However, when the document 26 is strongly inserted and a force equal to or greater than the predetermined value is applied to the lower abutment portion 94, as shown in FIG. Move backward in the feed direction). At this time, the stopper 93 rotates in the clockwise direction against the urging force of the torsion coil spring while contacting the rotating body 92. That is, the stopper 93 rotates together with the rotating body 92 in the clockwise direction around the support shaft 95 of the rotating body 92. Further, with the rotation of the stopper 93, the upper contact portion 99 presses the protruding portion 67 of the lock member 64, the support shaft 65 of the lock member 64 rotates in the counterclockwise direction, and the hook-like portion 66 becomes the latching portion. The hook 66 is released from the hook 70, and the hook 66 and the hook 70 are released. (See FIG. 3B). That is, when the stopper 93 is displaced in the clockwise direction, the lock state of the cover 13 by the lock member 64 is released. Accordingly, as shown in FIG. 8B, the cover 13 can be rotated from the closed posture to the open posture. At this time, the cover 13 rotates upward against its own weight by the urging force of the torsion coil spring provided on the support shaft 20 (see FIG. 2).

  As described above, since the regulating member 90 and the lock member 64 are provided, even if the document 26 is vigorously inserted into the feeding tray 12 and a force greater than the predetermined value is applied to the stopper 93, the stopper 93 does not move. Since it moves backward, the stopper 93 and its peripheral members are prevented from being damaged. Further, the cover 13 which has been in the closed position is brought into the open position by the backward movement of the stopper 93. Therefore, when the cover 13 is opened, the user inserts the leading end portion 26A of the document 26 to the downstream side in the feeding direction from the restriction position by the restriction member 90 (the feeding position that can be fed by the pickup roller 79). I can recognize that. That is, the user can recognize that the distal end portion 26A has reached an abnormal position. At this time, the user returns the cover 13 to the closed position after removing the original 26 and places the original 26 on the feeding tray 12 again. However, once the cover 13 is in the open position, the user When the document 26 is placed again, the force for inserting the document 26 can be adjusted. In other words, when the cover 13 is opened, the user can grasp the force level when moving the leading end portion 26A of the document 26 to an accurate position when the document 26 is reinserted.

  In the above-described embodiment, the ADF 10 is illustrated as an embodiment of the present invention, but the present invention is not limited to this. As shown in FIG. 9, the present invention may be realized as an image reading apparatus 110 including an ADF 10. Specifically, the present invention can also be applied to the image reading device 110 configured by the light source unit 111 including the LED 114 and the mirror 121, the CCD 125, the optical lens 126, the mirrors 122 and 123, the control unit 130, the ADF 10, and the like. Further, as shown in FIG. 10, a paper feed tray 146, a transport unit 147, a transfer device 148, a fixing device 149, a manual feed tray 150, an ADF 10, an image reading device 110 and the like are provided, and an image of a document transported by the ADF 10 is displayed. The present invention is also applicable to an image forming apparatus 140 that is read by the image reading apparatus 110 and forms an image on a print sheet based on the read image.

10: automatic document feeder 11: main body 12: feeding tray 13: cover 14: discharge tray 37: transport path 40: feeding mechanism 47: operation lever 64: lock member 73: drive shaft 79: pickup roller 80: feeding Roller 90: Restricting member 92: Rotating body 93: Stopper

Claims (6)

A sheet placement section on which the sheet is placed;
Conveying means for conveying the sheet placed on the sheet placing portion to the inside of the apparatus main body;
An end portion of the sheet placed on the sheet placement portion in the conveyance direction by the conveyance unit is regulated at a conveyance position that can be conveyed by the conveyance unit, and the end portion of the sheet is opposed to the regulation at the conveyance position. A restricting portion that is displaced in the transport direction when moved in the transport direction from the transport position;
A movable part capable of changing an attitude between a first attitude covering a part of the apparatus main body and a second attitude separated from the first attitude;
A holding unit that holds the movable unit in the first posture, and releases the holding of the movable unit when the regulating unit is displaced in the transport direction;
A rotationally driven drive shaft;
A first transmission unit that transmits a rotational driving force of the drive shaft to the transport unit;
A sheet conveying apparatus comprising: a second transmission unit configured to transmit a rotational driving force of the drive shaft to the regulating unit and move the regulating unit in a direction away from the sheet placing unit.   The movable portion is rotatably supported by the apparatus main body and opens and closes a sheet conveyance path formed in the apparatus main body. The first posture is an attitude that covers a part of the sheet conveyance path. The sheet conveying apparatus according to claim 1, wherein the second posture is a posture in which a part of the sheet conveying path is opened.   The sheet conveying apparatus according to claim 1, further comprising an operation lever that is provided in the apparatus main body and is operated to release the holding of the movable portion in the first posture by the holding portion. Said drive shaft, said first transmission portion, the second transmission unit, and the regulating portion, the sheet conveying device according to any one of claims 1 to 3, which is supported by the movable portion. Image reading apparatus having a sheet conveying apparatus according to any one of claims 1 to 4. Image forming apparatus having a sheet conveying apparatus according to any one of claims 1 to 4.

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