JP2011126676A - Sheet material feeder and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet material feeder capable of taking out an initial position without arranging a position detecting means of a cam in addition to a position regulating means of the cam. <P>SOLUTION: This sheet material feeder includes a bottom plate 15 for stacking paper P, a feed roller 16 for feeding the stacked paper P, a compression spring 29 for energizing the paper P and the feed roller 16 in abutment, a cam 18 for separating the paper P and the feed roller 16 by moving the bottom plate 15 against its energizing force, its driving source, a disk 19 interlocking with the cam 18, three claw parts possessed by the disk 19, an arm 20 for regulating rotation of the disk 19 by engaging with these parts and a solenoid SOL being its moving means. The arm 20 includes a plurality of engaging parts for engaging with the claw parts of the disk, and the disk 19 engages the arm 20 and a first claw when the cam 18 exists in a position for pushing down the bottom plate 15, and engages the arm 20 and a second claw when separated from the bottom plate 15, and engages a third claw with thee arm 20 when the cam 18 exists in an optional position. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a sheet material feeding apparatus that is applied to an image forming apparatus that forms an image on a sheet material such as paper and separates and feeds stacked sheet materials one by one.

  Conventionally, as this type of sheet material feeding device, the sheet material loaded on the stacking member is brought into contact with the feeding member and a biasing pressure is applied to feed the sheet material by a frictional force. There is a device. In addition, from the viewpoint of improving sheet material setting properties, the sheet material provided with lifting means for contacting the sheet material stacked on the stacking member only when the sheet material is fed and the feeding member and separating the sheet material after the feeding is finished. There is also a feeding device.

  As the lifting and lowering means of such a sheet material feeding device, a biasing means that biases the stacking member in a direction to contact the feeding member, and a stacking member that is separated from the feeding member against the biasing means. Those having a cam mechanism are widely used.

  In such a sheet material feeding apparatus, it is necessary to stop the cam at a predetermined position in a series of feeding operations, and a flapper or the like is engaged with the claw portion provided on the cam or a rotating member interlocked with the cam. In this way, the cam rotation is regulated.

  The position at which the cam is stopped includes a feeding position where the stacking member comes into contact with the feeding member at a predetermined pressure and the sheet material can be fed, and a setting where the stacking member is separated from the feeding member and the sheet material can be easily set. It is desirable to be able to stop at at least two locations. For example, in Patent Document 1, the bottom plate operation cam is stopped in a state in which the bottom plate is raised and a state in which the bottom plate is pushed down by providing lock claws at two locations in a one-turn clutch that transmits driving force to the drive shaft. The invention characterized by this is disclosed. Patent Document 2 discloses an invention in which a plurality of claws are provided in a second transmission means for selectively transmitting power to a cam member, and the cam member is stopped at a predetermined rotation angle.

  However, the cam position may stop at an unexpected position due to, for example, an impact applied to the machine or a user operation. In order to be able to resume the feeding operation from such a situation, an initial operation for returning the cam to a predetermined position is necessary, but this cannot be solved.

  In Patent Document 3, as an initialization operation, the idler gear is rotated a predetermined number of times, and the cam gear is engaged with either the first or second latch portion of the second cam, and which latch portion is engaged. Is determined by a photo interrupter. However, in recent years, there has been a demand for downsizing and reduction in power consumption in an image forming apparatus equipped with a sheet material feeding device, and it is desirable to perform initial operation with a simpler and smaller configuration. It has not been solved.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a sheet material feeding apparatus that solves the above-mentioned conventional problems and an image forming apparatus using the same.

  The sheet material feeding device according to claim 1 of the present invention includes a stacking member for stacking sheet materials, a feeding member for feeding sheet materials stacked on the stacking members, and the stacked sheet materials. An urging member that urges the stacking member toward the feeding member so that the feeding member abuts, and abuts against the stacking member, and moves the stacking member against the urging force of the urging member A cam that separates the sheet member from the feeding member, a drive source that rotationally drives the cam, a rotating member that rotates in conjunction with the cam, and a claw provided on the rotating member that engages with the claw. In the sheet material feeding apparatus including a regulating member that regulates rotation of the rotating member, and a moving unit that moves the regulating member to a position where the regulating member is engaged with a claw portion provided on the rotating member, the regulating member is configured to rotate the rotating member. A plurality of engaging portions that engage with the claw portions of the member; The member includes a first claw that engages with the restriction member when the cam is in a position to push down the loading member, and a second claw that engages with the restriction member when the cam is separated from the loading member. It has a nail | claw and a 3rd nail | claw engaged with the said limitation member when the said cam exists in arbitrary positions, It is characterized by the above-mentioned.

  According to a second aspect of the present invention, in the sheet feeding apparatus according to the first aspect, the restricting member includes a first engaging portion that can be engaged with the first and second claws of the rotating member; And a second engaging portion engageable with the third claw of the rotating member.

  According to a third aspect of the present invention, in the sheet feeding apparatus according to the first or second aspect, the moving means for moving the regulating member is an electromagnetic solenoid.

  According to a fourth aspect of the present invention, in the sheet material feeding device according to any one of the first to third aspects, the feeding member is a feeding roller, and the cam is disposed coaxially with the feeding roller. It is characterized by that.

  According to a fifth aspect of the present invention, in the sheet material feeding device according to any one of the first to fourth aspects, the rotating member is formed integrally with the cam.

  An image forming apparatus according to a sixth aspect includes the sheet material feeding device according to any one of the first to fifth aspects.

  In the sheet material feeding device according to the present invention, a third claw for providing an initial position is provided on a rotating member interlocked with the cam, and the initial position is provided without providing a cam position detecting means in addition to the cam position regulating means. The effect that the position can be obtained can be achieved.

Schematic configuration diagram of an image forming apparatus according to the present invention 1 is a schematic perspective view of a manual sheet feeding unit as an embodiment of a sheet material feeding device according to the present invention. Schematic cross-sectional view showing the configuration of a feed roller as a feed member Schematic sectional view showing the configuration of the lifting means Overview (A) and top view (B) showing the configuration of the disk and arm Diagram for explaining the initial operation before feeding the sheet material Diagram showing the state of the disk and arm during feeding operation The figure which shows the example which formed the resin-made cam and the disk which is a rotating member integrally by injection molding The figure which shows the example which provided the 3 nail | claw part of the disk in the outer periphery

An embodiment of a sheet material feeding device of the present invention will be described.
In the sheet material feeding device according to the present invention, a third claw for providing an initial position is provided on a rotating member interlocked with a cam. With this configuration, the initial position can be obtained without providing the cam position detecting means in addition to the cam position regulating means. Further, the engaging portion of the restricting member that restricts the position of the rotating member is divided into a first engaging portion that engages with the first and second claws of the rotating member by the feeding operation, and an initial operation of the cam. It divides into the 2nd engaging part engaged with a 3rd nail | claw. With this configuration, the feeding operation and the initial operation can be performed simply by switching the regulating member to two positions. Further, an electromagnetic solenoid is used as means for moving the regulating member. Therefore, switching between the two positions is facilitated, and the regulating member can be held at a position where it engages with the first and second claws of the rotating member without consuming electric power during the feeding operation. Further, the feeding member is used as a feeding roller, and the cam is arranged coaxially with the feeding roller. By doing so, it is possible to make the rotation shaft of the feeding member and the rotation shaft of the cam the same, and it is possible to reduce the number of parts of the apparatus and to reduce the size and weight. Furthermore, the cam and the rotating member are integrally formed. With this configuration, the interlocking between the cam and the rotating member is inevitably achieved. Further, the reliability as the sheet material feeding device is improved, and the number of parts can be reduced. By providing any one of these sheet material feeding apparatuses in the image forming apparatus, the number of parts can be reduced as the image forming apparatus.

  In the invention disclosed in Patent Document 1, when the pull-back claw member performs a pull-back operation, the sheet feed motor is used in response to a sheet feed command in order to contact the fed sheet material and impair the flatness and reduce the conveyance accuracy. When the sheet feeding clutch is operated for the first time, the feeding roller and the bottom plate operation cam rotate, and the uppermost sheet material of the sheet material stacked on the bottom plate comes into contact with the feeding roller. The uppermost sheet material is fed while being separated, and the sheet feeding clutch stops in a half turn, so that the sheet feeding roller is also stopped, and then the rear end of the fed sheet material is pulled back by the pull-back claw member. At the timing after passing through the moving range, the feed clutch is driven (second operation) to rotate the remaining half turn, and the bottom plate operation cam pushes down the bottom plate and pulls back in conjunction with this. Sheet material 1 loaded with claw members 1 The operation of pulling back the tip. That is, although the bottom plate operation cam stops in half a turn, the initial position of the bottom plate operation cam is not controlled.

  In the invention disclosed in Patent Document 2, a sheet stacking member, a feeding rotating body that feeds a sheet material, a cam member that contacts or separates the feeding rotating body and the sheet material, a feeding rotating body, and a cam In a feeding device having a driving source for applying a driving force to a member, a first transmission means for selectively transmitting the driving force of the driving source to the feeding rotating body and a driving force of the driving source to the cam member are selected. Engaged with the second transmission means for transmission and the claw formed on the first transmission means to stop the feeding rotating body at an arbitrary rotation angle, and at the same time, the first or second formed on the second transmission means An engagement position that engages with the second claw and stops the cam member at a predetermined rotation angle, and a non-engagement that does not engage with any of the above-mentioned claws and transmits the drive by the first and second transmission means And a control member movable to the position. In other words, the second transmission means for selectively transmitting the cam member driving force is provided with a plurality of claws to stop the cam member at a predetermined rotation angle, but the initial rotation angle of the cam member is controlled. Is not done.

  Further, in the invention disclosed in Patent Document 3, in order to be able to separately control the raising / lowering operation of the intermediate plate and the rotation driving of the paper feed roller, the rotation of the cam for raising / lowering the intermediate plate is a swing gear that meshes with the gear of the cam gear. Is transmitted from. When the oscillating gear is engaged, the drive is transmitted from the idler gear, the cam gear rotates, the cam rotates, and the middle plate moves up and down. The rotation of the paper feed roller is transmitted by an electromagnetic clutch, so that the rotation of the paper feed roller and the raising / lowering operation of the intermediate plate can be controlled separately, and the idler gear is rotated by a predetermined number of times by the initializing operation. Is engaged with either the first or second latch part of the second cam, but it is determined using the photo interrupter which latch part is engaged, but it is engaged in the initial operation. The position to do is not specified.

  Embodiments of the present invention will be described below with reference to the drawings. The present invention is not limited to the illustrated image forming apparatus, and can be applied to various apparatuses that perform image formation.

  FIG. 1 is a schematic configuration diagram of an image forming apparatus according to the present invention. The illustrated image forming apparatus 1 includes a main body sheet feeding unit 2 and a manual sheet feeding unit 3 as a sheet material feeding device that conveys a sheet material to an image forming unit. The paper P fed from each paper feed unit is fed to the registration roller 4 and fed to the image forming unit 5 by the registration roller 4. The image forming unit 5 includes a photoconductor unit 6, an intermediate transfer unit 7, an exposure unit 8 using laser light L, and the like. The transfer unit 9 transfers a toner image onto the surface of the paper P, and the paper P on which the toner image is transferred. And a fixing unit 10 that performs a fixing process by heating under pressure. The sheet P on which the image has been formed is discharged by a discharge roller 11 to a discharge tray unit 12 at the top of the apparatus main body 1. Further, at the upper part of the image forming apparatus, there are a display unit 13 and an operation unit 14 that indicate the operating state of the apparatus and instructions to the user.

  FIG. 2 is a schematic perspective view of a manual sheet feeding unit 3 as an embodiment of the sheet material feeding apparatus according to the present invention. FIG. 3 is a schematic sectional view showing the configuration of the feeding roller 16 as a feeding member, and FIG. 4 is a schematic sectional view showing the configuration of the lifting means.

  In FIG. 3, the manual paper feed unit is provided with a manual paper feed tray 24 that can be opened and closed from the image forming apparatus main body 1 and a bottom plate 15 made of a flat plate material as a stacking member. The bottom plate 15 is rotatably mounted at a fulcrum 25 provided on the side surface of the manual paper feed tray 24. Above the bottom plate 15, a feeding roller 16 that is a feeding member fixed to the feeding roller shaft 17 is installed. Further, a friction separation mechanism using a known friction pad system is provided downstream of the bottom plate 15 in the feeding direction in order to prevent double feeding of the sheet material P. That is, the separation pad 27 formed of a material having a high friction coefficient such as an elastic material is attached to the receiving base 28 and is urged toward the feeding roller by the compression spring 29.

  Next, the structure of the lifting / lowering means 18 for the stacking member in the present embodiment will be described. A conical spring 26 as an urging member is provided between the bottom plate 15 and the manual feed tray 24 and urges the bottom plate 15 toward the feeding roller 16. The feed roller shaft 17 is provided with a cam 18 that is not fixed to the feed roller shaft 17 on the outer side in the width direction of the sheet P that is a sheet material.

  The cam 18 is provided with a disk 19 and a spring clutch 21 which are rotating members that rotate in conjunction with the cam. The spring clutch 21 is engaged with a cam drive gear 22, and the cam drive gear 22 is connected to a cam drive motor (not shown) as a drive source via an idler gear 23.

  When the cam drive motor is driven and the cam drive gear 22 rotates, the drive is transmitted from the spring clutch 21 to the disk 19 and the cam 18. The cam 18 contacts the cam engaging portion 15 a provided at the end of the bottom plate 15 while rotating, pushes down the bottom plate 15 against the urging force of the spring 26, and separates the bottom plate 15 from the feeding roller 16.

  The disk 19 is engaged with an arm 20 that is a restricting member that restricts the rotation of the disk. When the arm 20 is engaged with the claw portion of the disk 19, the spring clutch 21 is loosened and the drive to the disk 19 is interrupted. Therefore, when the arm 20 is engaged with the disk 19, the cam 18 can be stopped.

  FIG. 5 is a schematic view and a top view showing the configuration of the disk 19 and the arm 20. The disc 19 is provided with claw portions 19-1 to 19-3 at three locations. The first claw portion 19-1 and the cam 18 that are engaged when the cam 18 pushes down the bottom plate 15 respectively. A second claw portion 19-2 that engages when separating and a third claw portion 19-3 that engages at an arbitrary position in the process of the cam pushing down the bottom plate.

  Further, the arm 20 can rotate around the rotation fulcrum 20a by suction of the solenoid SOL. The arm 20 is provided with two engaging portions 20-1 and 20-2 for engaging with the claw portions 19-1 to 19-3 of the disk 19, and the first engaging portion 20-1 is When the solenoid SOL is not energized, the first and second claw portions 19-1 and 19-2 of the disk 19 can be engaged. The second engagement portion 20-2 of the arm 20 can be engaged with the third claw portion 19-3 of the disk 19 only when the solenoid SOL is energized and the arm 20 moves.

  Next, the initial operation before feeding the sheet material in this embodiment will be described with reference to FIG. The initial operation is performed for the purpose of moving the cam 18 stopped at an unspecified position to the initial position. In order to improve the sheet setting property, the initial position is set to a position where the cam 18 pushes down the bottom plate 15.

  First, a suction operation is performed with the solenoid SOL (the solenoid SOL shown in the figure is indicated as “pulling” indicating that suction is performed). At this time, the arm 20 rotates about the arm fulcrum 20a, and the second engaging portion 20-2 moves to a position where it engages with the third claw portion 19-3 of the disk 19 (FIG. 6A). )reference).

  Next, while maintaining the suction by the solenoid SOL, the cam drive motor is driven for a predetermined time so that the disk 19 makes one rotation or more. During the rotation, the second claw portion 19-3 of the disk 19 and the second engagement portion 20-2 of the arm 20 are engaged, and the rotation of the disk is restricted. (See FIG. 6B).

  The cam drive motor and idler gear 23 and the cam drive gear 22 continue to rotate even after the claw portion 19-3 and the engagement portion 20-2 are engaged, but the drive to the disk 19 is cut off because the spring clutch 21 is loosened. Is done.

  Then, after the cam drive motor finishes driving for a predetermined time, the energization of the solenoid SOL is turned off, and the engagement between the arm 20 and the disk is released. The cam drive motor is driven again, and after the first engagement portion 20-1 of the arm 20 is engaged with the first engagement portion 19-1 of the disk 19, the cam drive motor is stopped (FIG. 6 ( C)).

  At this time, the cam 18 stops at a position where the bottom plate 15 is pushed down. And by the above operation | movement, the cam 18 in an unspecified position can be moved to the position (initial position) which pushes down the baseplate 15 without using a cam position detection sensor.

  Next, the sheet material feeding operation in this embodiment will be described with reference to FIG. FIG. 7 shows the state of the disk 19 and the arm 20 during the feeding operation.

  After completion of the initial operation, as described above, the first engagement portion 20-1 of the arm 20 and the first claw portion 19-1 of the disk 19 are engaged and stopped. (See FIG. 7A). At this time, the cam 18 is stopped at a position where the bottom plate 15 is pushed down.

  When receiving a signal for starting the feeding operation, first, an operation of separating the cam 18 from the bottom plate 15 is performed. First, the cam drive motor is driven, and the cam drive gear 22 rotates. However, the disk 19 is not rotated because it is subject to the rotation restriction by the arm 20. Next, the solenoid SOL is energized for a short time, and the engagement between the first engagement portion 20-1 of the arm 20 and the first claw portion 19-1 of the disk 19 is released.

  When the engagement is released, the disk 19 is rotated by receiving a drive from the spring clutch 21 (see FIG. 7B), and the first engaging portion 20-1 of the arm 20 and the second pawl of the disk 19 are rotated. It stops when the part 19-2 engages (see FIG. 7C).

  At this time, the cam 18 interlocked with the disc 19 shifts from a state where the bottom plate 15 is pushed down to a state where it is separated from the bottom plate 15. When the cam 18 and the bottom plate 15 are separated from each other, the urging force by the conical spring 26 is released as shown in FIG. 3, and the paper P stacked on the bottom plate 15 can be brought into contact with the feeding roller 16 with a predetermined pressure and fed. It becomes. The feeding roller 16 is intermittently rotated using an electromagnetic clutch (not shown) to feed the paper P into the image forming apparatus.

  When the signal indicating the end of the feeding operation is received, an operation of shifting the cam 18 to the state where the bottom plate 15 is pushed down again is performed, the cam drive motor is driven, and the cam drive gear 22 is rotated. The solenoid SOL is energized for a short time, and the engagement between the first engagement portion 20-1 of the arm 20 and the second claw portion 19-2 of the disk 19 is released. When the engagement is released, the disk 19 is driven by the spring clutch 21 and rotates (see FIG. 7C).

  The disc 19 stops when the first engagement portion 20-1 of the arm 20 and the first claw portion 19-1 of the disc 19 are engaged, and returns to the initial state (see FIG. 7D).

  At this time, the cam 18 is stopped at a position where the bottom plate 15 is pushed down. By repeating the above operation based on a feed operation start command, it is possible to feed a sheet to the image forming apparatus at an arbitrary timing.

  The cam 18 and the rotating member 19 that rotates in conjunction with the cam may be integrally formed. FIG. 8 shows an example in which a resin cam 18 and a disk 19 as a rotating member are integrally formed by injection molding.

  Further, the claw portion of the rotating member may be provided on the outer periphery of the disk 19. FIG. 9 shows an example in which the claw portions 19-1 to 19-3 of the disk 19 are provided on the outer periphery. On the outer periphery of the disk 19, first and second claw portions 19-1 and 19-2 are provided at a distance A on the rotation axis of the disk from the end face of the cam 18. A claw portion 19-3 is provided. The arm 20 engaged with the disk 19 can engage with the first and second claw portions 19-1 and 19-2 located at the distance A by reciprocating by 180 ° about the arm support shaft 20b. The state (FIG. 9A) and the state (FIG. 9B) that can be engaged with the third claw portion 19-3 located at the distance B can be switched.

1: Device main body 2: Main body paper feed unit 3: Manual feed unit 4: Registration roller 5: Image forming unit 6: Photosensitive unit 7: Intermediate transfer unit 8: Exposure unit 9: Transfer unit 10: Fixing unit 11: Paper discharge roller 12: Paper discharge tray 13: Display unit 14: Operation unit 15: Bottom plate 16: Feed roller 17: Feed roller shaft 18: Cam 19: Disks 19-1 to 19-3: First to first disks 3 claw portion 20: arm 20a: arm fulcrum 20b: arm support shaft 20-1, 20-2: first and second engagement portions 21 of arm: spring clutch 22: cam drive gear 23: idler gear 24: manual feed Paper feed tray 25: Bottom plate fulcrum 26: Conical spring (paper feed)
27: separation pad 28: cradle 29: compression spring (separation)
30: Guide plate 31: Bottom plate pad P: Paper SOL: Solenoid

JP 2008-30910 A Japanese Patent Publication No. 2-62451 JP-A-8-217265

Claims (6)

A stacking member for stacking the sheet material, a feeding member for feeding the sheet material stacked on the stacking member, and the stacking member to the feeding member so that the stacked sheet material and the feeding member come into contact with each other An urging member that urges toward the sheet, a cam that contacts the stacking member, moves the stacking member against the urging force of the urging member, and separates the sheet material and the feeding member; and rotates the cam A driving source for driving, a rotating member that rotates in conjunction with the cam, a restricting member that engages with a claw provided on the rotating member to restrict the rotation of the rotating member, and the restricting member as the rotating member In the sheet material feeding apparatus provided with a moving means for moving to a position that engages with the provided claw portion,
The restricting member has a plurality of engaging portions that engage with the claw portions of the rotating member,
The rotating member is
A first claw that engages with the restriction member when the cam is in a position to push down the stacking member;
A second claw that engages with the restriction member when the cam is separated from the stacking member;
A third claw that engages with the restriction member when the cam is in an arbitrary position;
A sheet material feeding device comprising: In the sheet feeding apparatus according to claim 1,
The regulating member is
A first engaging portion engageable with the first and second claws of the rotating member;
A second engaging portion engageable with the third claw of the rotating member;
A sheet material feeding device comprising: In the sheet feeding apparatus according to claim 1 or 2,
A sheet material feeding device, wherein the moving means for moving the regulating member is an electromagnetic solenoid. In the sheet | seat material feeding apparatus in any one of Claim 1 to 3,
The feeding member is a feeding roller;
The cam is disposed coaxially with the feed roller;
A sheet material feeding device characterized by that. In the sheet material feeding device according to any one of claims 1 to 4,
The sheet material feeding device, wherein the rotating member is formed integrally with the cam. An image forming apparatus comprising the sheet material feeding device according to claim 1.