JP6607169B2 - DRIVE DEVICE, SHEET CONVEYING DEVICE HAVING DRIVE DEVICE, AND IMAGE FORMING DEVICE - Google Patents

Description

  The present invention relates to a driving device used in a sheet conveying apparatus and an image forming apparatus.

  A conventional color image forming apparatus such as a copying machine or a printer is configured to be able to switch between black monochromatic image formation and multicolor image formation. In general, single-color image formation and multicolor image formation have different development process speeds. For this reason, a conventional image forming apparatus is provided with a driving device for switching between a monochrome image forming operation and a color image forming operation.

  As this type of driving device, there is known a driving device capable of switching between a monochrome image forming operation and a color image forming operation by changing the rotation direction of a single motor (see Patent Document 1). . The drive device includes a swing gear for switching a drive transmission path of the rotational driving force of the motor, and a bracket that supports the rotation shaft of the swing gear so as to be movable while supporting the rotation shaft. ing. In the drive device, the rotation shaft of the swing gear is supported by a substantially elliptical support hole (sliding hole) formed in the bracket.

JP 2012-200909 A

  However, in the conventional drive device described in the above-mentioned Patent Document 1, since the support hole is formed in the bracket, the bracket itself is formed of a material having a small friction coefficient with respect to the rotation shaft. In addition, there is a problem that the rotating shaft continues to rotate without moving. In this case, the rotational driving force of the motor is not transmitted to the drive output unit, resulting in malfunction of the paper feeding device and the image forming apparatus.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a driving device capable of reliably transmitting a rotational driving force to a driving output unit by reliably moving a rotating shaft of a moving gear for switching a driving transmission path, and a seat including the driving device. The object is to provide a transport device and an image forming apparatus.

  The drive device which concerns on one situation of this invention is a drive device which switches the rotational speed of a drive output part. The drive device includes a drive source, a drive gear, a moving gear, a first drive transmission unit, a second drive transmission unit, a bracket, and a load member. The driving source supplies a rotational driving force. The drive gear is disposed so as to be rotatable in a first direction and a second direction in accordance with forward and reverse rotations of the drive source. The moving gear is disposed so as to mesh with the driving gear, and is configured to be swingable between a first position and a second position by the rotational driving force transmitted from the driving gear. The first drive transmission unit meshes with the moving gear when the moving gear swings to the first position due to rotation of the driving gear in the first direction, and outputs the rotational driving force to the driving output unit. To communicate. The second drive transmission portion meshes with the movement gear when the movement gear swings to the second position as the drive gear rotates in the second direction, and the second drive transmission portion is engaged with the first drive transmission portion. The rotational driving force is transmitted to the drive output unit at different reduction ratios. The bracket has a support hole for guiding the moving gear to the first position and the second position by supporting the rotating shaft of the moving gear so as to be movable in a lateral direction and rotatable. The bracket includes a load member that applies a load between a support surface of the rotation shaft in the support hole and the rotation shaft.

  A sheet conveying apparatus according to another aspect of the present invention includes the drive device. The sheet conveying device conveys a sheet by a rotational driving force output from the driving device.

  An image forming apparatus according to another aspect of the present invention includes the drive device. The image forming apparatus operates each driving unit of the image forming unit included in the image forming apparatus by a rotational driving force output from the driving device.

  According to the present invention, it is possible to reliably transmit the rotational driving force to the drive output unit by reliably moving the rotation shaft of the moving gear for switching the drive transmission path.

FIG. 1 is a perspective view showing a configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a diagram showing an internal configuration of the image forming apparatus shown in FIG. FIG. 3 is a top view illustrating a configuration of a driving device included in the image forming apparatus. FIG. 4 is a perspective view showing an internal configuration of the driving device. FIG. 5 is a front view showing the configuration of the driving device. FIG. 6 is a perspective view showing the configuration of the moving gear of the driving device and its bracket. FIG. 7 is a perspective view showing the configuration of the bracket of the moving gear. FIG. 8 is a cross-sectional perspective view of the moving gear and the bracket when cut along a cutting plane VIII-VIII passing through the center of the rotating shaft of the moving gear in FIG. 6. 9 is a cross-sectional perspective view of the bracket when cut along a cutting plane IX-IX passing through the center of the guide hole in FIG. FIG. 10 is a schematic cross-sectional view showing the configuration of another embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The following embodiment is an example embodying the present invention, and does not limit the technical scope of the present invention. For convenience of explanation, the vertical direction of the installation state (the state shown in FIG. 1) in which the image forming apparatus 10 according to the embodiment of the present invention can be used is defined as the vertical direction 6. Further, the front-rear direction 7 is defined with the surface on which the operation display panel 17 is provided in the installed state as the front surface (front surface). Further, a left-right direction 8 is defined with reference to the front of the image forming apparatus 10 in the installed state.

  First, the configuration of the image forming apparatus 10 will be described with reference to FIGS. 1 and 2.

  As shown in FIG. 1, the image forming apparatus 10 is a multi-function machine having functions such as a printer, a copier, a FAX apparatus, and a scanner. The image forming apparatus 10 forms an image on a print sheet using a printing material such as toner from the input image. Note that the image forming apparatus 10 is not limited to a multifunction machine, and the present invention can be applied to a dedicated machine such as a printer, a copying machine, or a FAX machine.

  The image forming apparatus 10 includes an image reading unit 12 and an image forming unit 14. The image reading unit 12 performs processing for reading an image of a document, and is provided on the upper part of the image forming apparatus 10. The image forming unit 14 performs a process of forming an image based on the electrophotographic method. The image forming unit 14 includes two sheet feeding devices 27 and 28 (an example of a sheet conveying device) arranged in two upper and lower stages. The upper sheet feeder 27 is provided integrally with the housing 29 at the lowermost part of the image forming unit 14. The lower sheet feeding device 28 is of an extension type connected as an optional device to the bottom surface of the casing 29 of the image forming unit 14. The paper feeding device 28 is configured to be detachable from the bottom surface of the housing 29. Further, on the right side of the image forming unit 14, a paper discharge unit 30 for discharging the print paper after image formation to the outside is provided. The image forming unit 14 is not limited to an electrophotographic type, and may be an inkjet recording type, or may be a recording method or printing method other than that.

  The image reading unit 12 reads image data of a document set on the document placing table 23. As shown in FIG. 2, the image reading unit 12 includes an ADF (automatic document feeder) 13. The ADF 13 is provided on the document cover 24. When the original is transported to the reading position by the ADF 13, the image of the original passing through the reading position is read by the image reading unit 12. In FIG. 1, illustration of the document cover 24 of the image reading unit 12 is omitted.

  The image forming unit 14 forms an image on a printing paper (sheet member) having a predetermined size such as an A size or a B size based on the image data read by the image reading unit 12 or image data input from the outside. To do. As shown in FIG. 2, the image forming unit 14 mainly includes paper feeding devices 27 and 28, an electrophotographic image transfer unit 18, a fixing unit 19, a paper transport unit 60, and a driving device 101. The printing paper on which the image is formed is discharged to the paper discharge space 21.

  The paper feeding devices 27 and 28 feed the printing paper to the vertical conveyance path 26. Each of the sheet feeding devices 27 and 28 includes a tray-shaped sheet storage unit 22 and a feeding mechanism 15 (15A and 15B). Printing paper on which an image is formed by the image transfer unit 18 is stacked in the paper storage unit 22. The feeding mechanism 15 is provided on the upper side of the right end portion of the paper storage unit 22. Each feeding mechanism 15 takes out and feeds the printing paper stored in the paper storage unit 22 one by one. The feeding mechanism 15A of the paper feeding device 27 includes a pickup roller 51A and a feeding roller pair 52A including a pair of rollers. The feeding mechanism 15B of the paper feeding device 28 includes a pickup roller 51B and a feeding roller pair 52B including a pair of rollers.

  An image transfer unit 18 is provided above the paper feeding device 27. The image transfer unit 18 includes a photosensitive drum 31, a charging unit 32, a developing unit 33, an optical scanning device 34, a transfer roller 35, and a cleaning unit 36.

  The fixing unit 19 fixes the toner image transferred to the printing paper on the printing paper by heat. The fixing unit 19 includes a heating roller 41 and a pressure roller 42. The fixing unit 19 fixes toner on the printing paper.

  A paper discharge port 37 through which printing paper is discharged is provided at the end of the vertical conveyance path 26. In the vicinity of the paper discharge port 37, a discharge roller pair 25 is provided. The print paper is conveyed from the paper discharge port 37 toward the paper discharge space 21 by the discharge roller pair 25.

  The drive device 101 rotationally drives the pickup rollers 51A and 51B of the paper feeding devices 27 and 28.

  Hereinafter, the configuration of the driving device 101 will be described in detail with reference to FIGS. 3 to 10.

  As shown in FIG. 3, the driving device 101 includes a rectangular parallelepiped casing 102 that is long in the horizontal direction. A support frame (not shown) is provided inside the housing 102. Each component constituting the driving device 101 is attached to the housing 102 and the support frame. The housing 102 is provided with a bracket 110 that holds a moving gear 123, which will be described later, in a swingable manner. The bracket 110 is fixedly held on the housing 102.

  As illustrated in FIG. 3, the driving device 101 includes a first output unit 105 and a second output unit 106. The driving device 101 switches the rotation speeds of the first output unit 105 and the second output unit 106. The first output unit 105 and the second output unit 106 are drive output units for outputting a rotational driving force of a motor 121 (an example of a drive source) described later. The first output unit 105 and the second output unit 106 are spaced apart in the longitudinal direction (width direction) of the housing 102. The first output unit 105 includes a rotation shaft 105A that protrudes outward from the side surface of the housing 102, and a first connection gear 105B that is fixed to the tip of the rotation shaft 105A. The second output unit 106 includes a rotation shaft 106A that protrudes outward from the side surface of the housing 102, and a second connection gear 106B that is fixed to the tip of the rotation shaft 106A.

  The first connection gear 105B is connected to the pickup roller 51A (see FIG. 2) so that the pickup roller 51A can rotate. The second connecting gear 106B is connected to the pickup roller 51B (see FIG. 2) so that the pickup roller 51B can rotate.

  FIG. 4 is a perspective view showing the internal structure of the driving device 101. In FIG. 4, the housing 102 is omitted.

  As shown in FIGS. 3 and 4, the driving device 101 includes a motor 121 that supplies rotational driving force, a driving gear 122, a moving gear 123, a first gear portion 124, a first input gear 125, A two-gear portion 126, an idle gear 128, a second input gear 129, a transmission gear 131, and a transmission gear 132 are provided. The drive gear 122, the first gear portion 124, the first input gear 125, the second gear portion 126, the idle gear 128, the second input gear 129, the transmission gear 131, and the transmission gear 132 are connected to the housing 102 and the support frame. It is rotatably held by each provided bearing portion. When the motor 121 is rotationally driven, the rotational driving force of the first transmission path R1 (see the broken line in FIG. 5) or the second transmission path R2 (see the dotted line in FIG. 5) described later depends on the rotational direction of the motor 121. The signal is transmitted to the first output unit 105 and the second output unit 106 via either one. In the present embodiment, the motor 121 is illustrated as an example of the driving source. However, the driving source of the present invention transmits the rotational driving force of the motor provided outside the driving device 101 to the driving gear 122 of the driving device 101. It may be a drive transmission mechanism such as a gear.

  As shown in FIG. 5, the first transmission path R <b> 1 transmits drive to the rotation shaft 105 </ b> A of the first output unit 105 via the drive gear 122, the moving gear 123, the first gear unit 124, and the first input gear 125. To the rotation shaft 106A of the second output unit 106 via the transmission gear 131, the transmission gear 132, the second gear unit 126, the idle gear 128, and the second input gear 129. Includes the transmission path. The gear group including the gears included in the first transmission path R1 transmits the rotational driving force of the motor 121 to the first output unit 105 and the second output unit 106 at a predetermined reduction ratio. It is an example of the 1st drive transmission part.

  The second transmission path R2 is a path for driving transmission to the rotary shaft 106A of the second output section 106 via the drive gear 122, the moving gear 123, the second gear section 126, the idle gear 128, and the second input gear 129. And a path that branches from the second gear portion 126 and transmits the drive to the rotating shaft 105A of the first output portion 105 via the transmission gear 132, the transmission gear 131, the first gear portion 124, and the first input gear 125. The gear group including the gears included in the second transmission path R2 applies the rotational driving force of the motor 121 to the first output unit 105 and the second output unit 106 at a reduction ratio different from that of the first transmission path R1. This is an example of the second drive transmission unit of the present invention.

  The driving apparatus 101 according to the present embodiment transmits the rotational driving force from the motor 121 to the first output unit 105 and the second output unit 106 via the first transmission path R1 according to the rotation direction of the motor 121. Alternatively, the signal is transmitted to the first output unit 105 and the second output unit 106 through the second transmission path R2. Accordingly, the driving device 101 can switch the rotation speeds of the first output unit 105 and the second output unit 106.

  The motor 121 is a DC brushless motor that can rotate forward and backward. The motor 121 is fixedly held below the housing 102. The motor 121 can change speed by changing the voltage applied to the motor 121. The motor 121 may be a stepping motor.

  A drive gear 122 composed of a spur gear is fixed to the motor shaft (output shaft) of the motor 121. Accordingly, when the motor 121 is driven to rotate in the forward rotation direction, the drive gear 122 rotates in the forward direction, and when the motor 121 is driven to rotate in the reverse rotation direction, the drive gear 122 rotates in the reverse direction. That is, the drive gear 122 rotates in a direction corresponding to the forward / reverse rotation of the motor 121. The drive gear 122 meshes with a moving gear 123 that is a spur gear. The drive gear 122 is not limited to a gear fixed to the motor 121 but may be a gear that meshes with an output gear fixed to the motor shaft of the motor 121. The drive gear 122 can also be a helical gear. Thereby, noise and vibration can be reduced.

  The bracket 110 is provided below the drive gear 122 and supports the rotating shaft 123 </ b> A of the moving gear 123 below the drive gear 122. The bracket 110 supports the moving gear 123 so that the driving gear 122 and the moving gear 123 mesh with each other. The bracket 110 is formed with a pair of guide holes 111 (an example of a support hole) for supporting both ends of the rotation shaft 123A in the axial direction. Each guide hole 111 is an inner hole of a cylindrical flange portion 112 protruding from each side surface of the bracket 110. The rotating shaft 123A of the moving gear 123 is supported by the guide hole 111 so as to be movable laterally (in the direction of arrow D21 or arrow D22 in FIG. 4) and to be rotatable.

  The guide hole 111 is a substantially elliptical long hole that is long in the longitudinal direction of the housing 102 (left-right direction in FIG. 3). The guide hole 111 is formed in an arc shape that is substantially concentric with the pitch circle of the drive gear 122. As a result, the moving gear 123 is easy to move while rotating in the width direction in the guide hole 111 while maintaining the meshing with the driving gear 122.

  The moving gear 123 is disposed so as to be movable between the first position (the position shown in FIGS. 4 and 5) and the second position when the turning shaft 123 </ b> A is supported by the guide hole 111. . In other words, the guide hole 111 supports the movable gear 123 so as to be movable and rotatable between the first position and the second position. Here, the first position is a position where the rotating shaft 123A abuts on an end surface 111A (see FIG. 5) on one side (first output portion 105 side) in the guide hole 111. Further, the second position is a position where the rotating shaft 123 </ b> A contacts the end surface 111 </ b> B (see FIG. 5) on the other side (second output unit 106 side) in the guide hole 111.

  When the motor 121 and the drive gear 122 are rotated in the first direction D11 shown in FIG. 4 by the rotational drive of the motor 121, the rotational drive force of the drive gear 122 is transmitted to the moving gear 123, and the guide hole 111 is transmitted by the rotational drive force. The rotary shaft 123A moves while rotating toward the end face 111A side (arrow D21 side in FIG. 4), and the moving gear 123 reaches the first position.

  On the other hand, when the motor 121 and the drive gear 122 rotate in the second direction D12 shown in FIG. 4 due to the rotational drive in the reverse direction of the motor 121, the rotational drive force of the drive gear 122 is transmitted to the moving gear 123, and the rotational drive force Thus, the rotation shaft 123A moves while rotating in the guide hole 111 toward the end face 111B side (arrow D22 side in FIG. 4), and the moving gear 123 reaches the second position.

  When the moving gear 123 reaches the first position, the moving gear 123 meshes with the first gear portion 124. At this time, the moving gear 123 is not meshed with the second gear portion 126. On the other hand, when the moving gear 123 reaches the second position, the moving gear 123 meshes with the second gear portion 126. At this time, the moving gear 123 is not meshed with the first gear portion 124.

  The first gear portion 124 is a spur gear. The first gear portion 124 meshes with the first input gear 125 and the transmission gear 131. Further, the transmission gear 131 meshes with the adjacent transmission gear 132.

  The first gear portion 124 is provided with an output gear 133 (see FIG. 3) attached integrally with the first gear portion 124 so as to be coaxial therewith. The output gear 133 is provided with an output shaft (not shown) that transmits a rotational driving force to the outside. The photosensitive drum 31, the transfer roller 35, the heating roller 41, the discharge roller pair 25, each conveyance roller in the vertical conveyance path 26 and the like in the image forming unit 14 are rotated by receiving the rotational driving force output from the output gear 133. The

  The second gear portion 126 is a spur gear. The number of teeth of the second gear portion 126 is set so that the reduction ratio is different from that of the first gear portion 124. The second gear portion 126 meshes with the transmission gear 132 and the idle gear 128. Further, the idle gear 128 meshes with the second input gear 129.

  When the motor 121 is driven to rotate in the forward direction, the driving gear 122 rotates in the first direction D11 (see FIG. 4), and the rotational driving force of the driving gear 122 is transmitted to the moving gear 123. It moves to the first position by a rotational driving force. In the first position, the moving gear 123 meshes with the first gear portion 124, and the rotational driving force is transmitted along the first transmission path R1 (see FIG. 5) via the first gear portion 124. The first connecting gear 105B of the first output unit 105 and the second connecting gear 106B of the second output unit 106 rotate at a predetermined rotational speed, respectively.

  When the motor 121 rotates in the reverse direction, the drive gear 122 rotates in the second direction D12 (see FIG. 4), and the rotational driving force of the drive gear 122 is transmitted to the moving gear 123. It moves to the second position by the rotational driving force. In the second position, the moving gear 123 meshes with the second gear portion 126, and the rotational driving force is transmitted along the second transmission path R2 (see FIG. 5) via the second gear portion 126, The first connecting gear 105B of the first output unit 105 and the second connecting gear 106B of the second output unit 106 rotate at a predetermined rotational speed, respectively. When the driving gear 122 rotates in the second direction D12, the first connecting gear 105B and the second connecting gear 106B are driven according to the difference in the reduction ratio of the second gear portion 126 with respect to the first gear portion 124. Rotate at different rotational speeds with respect to the case of rotating in the first direction D11.

  As described above, the rotational speed of the first connection gear 105B of the first output unit 105 and the second connection gear 106B of the second output unit 106 are changed by switching the rotation direction of the motor 121 by configuring the drive device 101. Can be easily changed.

  Next, the bracket 110 for supporting the moving gear 123 will be described.

  As shown in FIGS. 6 and 7, the bracket 110 includes the above-described guide hole 111, side surface base portions 110A and 110B constituting both side surfaces of the bracket, mounting holes 110C and 110D, and a pair of built-in holes 110E (FIG. 6). Reference).

  The side bases 110A and 110B are formed to face each other and are connected to each other on the lower side thereof, so that the upper side is opened so that the moving gear 123 can protrude and house a part thereof. Has been.

  Mounting holes 110C and 110C are formed on the left and right sides of the side base portion 110A. The bracket 110 is fixed to the housing 102 by fitting the mounting holes 110C and 110D into a pair of protrusions (not shown) formed in the housing 102 (see FIG. 3).

  A guide hole 111 is formed on the upper side of each center of the side bases 110A and 110B. Each guide hole 111 is formed by a flange portion 112 projecting outward from the side base portions 110A and 110B. Specifically, the guide hole 111 is an inner hole of the flange portion 112. The guide hole 111 includes a circular arc surface 111C that constitutes both upper and lower surfaces (upper surface and lower surface) of the guide hole 111, and semicircular end surfaces 111A and 111B provided at both ends of the circular arc surface 111C. Each arcuate surface 111C is formed such that the rotating shaft 123A of the moving gear 123 can move between the end surfaces 111A and 111B. The rotating shaft 123A of the moving gear 123 can move in the width direction in the circular arc surface 111C, and can rotate in a state of being in contact with one of the end surfaces 111A and 111B.

  Even if the rotating shaft 123A of the moving gear 123 rotates in a state where it is in one-side contact with one of the end surfaces 111A and 111B of the guide hole 111 for a long period of time, the arc surface is in contact with the arc surface 111C of the guide hole 111. Even if the 111C is repeatedly moved, the rotation shaft 123A of the moving gear 123 is worn and the end surfaces 111A and 111B of the guide hole 111 are suppressed from being worn away. Each material is combined. That is, the bracket 110 is formed into the predetermined shape with PBT (polybutylene terephthalate) resin, and the moving gear 123 is made of polyacetal resin. Accordingly, the bracket 110 has higher rigidity than the moving gear 123, and the rotating shaft 123A of the moving gear 123 rotates in a state where it is in one-side contact with one of the end surfaces 111A and 111B of the guide hole 111 of the bracket 110 for a long period of time. Even so, it is possible to prevent the end surfaces 111A and 111B of the guide hole 111 from being worn away. Moreover, the housing | casing 102 consists of PPE (polyphenylene ether) resin containing a glass filler, and is equipped with the intensity | strength which hold | maintains the motor 121 and several gears. On the other hand, since the bracket 110 has a smaller friction coefficient and better sliding performance than the housing 102, there is no possibility that the rotating shaft 123A of the moving gear 123 is worn.

  As shown in FIGS. 8 and 9, the side base portions 110 </ b> A and 110 </ b> B of the bracket 110 and the flange portions 112 are respectively formed with built-in holes 110 </ b> E drilled on the upper side thereof. The assembly hole 110E is for incorporating the moving gear 123 into the bracket 110. The pair of built-in holes 110E are slightly shorter than the axial length of the rotating shaft 123A of the moving gear 123, and are slightly larger than the outer peripheral portion of the rotating shaft 123A in the width direction.

  When assembling the moving gear 123 into the bracket 110, when the rotating shaft 123A of the moving gear 123 is pushed against the mounting hole 110E of the bracket 110, the mounting hole 110E of the bracket 110 expands in the axial direction of the rotating shaft 123A. The rotation shaft 123A is inserted into the mounting hole 110E of the bracket 110. When the rotating shaft 123A of the moving gear 123 is inserted into the mounting hole 110E of the bracket 110, the expanded mounting hole 110E is restored, and the rotating shaft 123A of the moving gear 123 is fitted into the guide hole 111 of the bracket 110.

  By the way, since the guide hole 111 is formed integrally with the bracket 110, when the bracket 110 itself is formed of a material having a small friction coefficient with respect to the rotation shaft 123A, the rotation shaft 123A moves in the width direction. There are cases where it continues to slide and rotate without moving. In particular, as described above, when the bracket 110 is made of a material having rigidity higher than that of the rotation shaft 123A in consideration of wear of the guide hole 111, the friction coefficient of the bracket 110 with respect to the rotation shaft 123A becomes small. When the rotary shaft 123A slips and does not move in the width direction, the rotational driving force of the motor 121 is not transmitted to the first output unit 105 and the second output unit 106, and the operations of the paper feeding devices 27 and 28 and the image forming apparatus 10 are performed. It will cause defects. For this reason, in this embodiment, as will be described later, the bracket 111 is provided with a rubber pad 140 (an example of a load member).

  The rubber pad 140 is a member that applies a load between the support surface of the rotating shaft 123A in the guide hole 111 and the rotating shaft 123A. As shown in FIGS. 8 and 9, the rubber pad 140 is formed by cutting a sheet-like elastic member such as NBR having a high frictional resistance into a rectangular shape, and is attached to the arc surface 111 </ b> C below the guide hole 111. ing. That is, the rubber pad 140 is a sheet-like friction member that generates a frictional resistance on the peripheral surface of the rotating shaft 123A when the rotating shaft 123A moves. In the present embodiment, the rubber pad 140 is provided in a rectangular recess formed on the upper surface of the arc surface 111C so that the upper surface of the rubber pad 140 and each end surface 111A, 111B of the guide hole 111 are the same surface. The rubber pad 140 may be made of any material as long as it generates a frictional resistance on the peripheral surface of the rotating shaft 123A with respect to the moving direction of the rotating shaft 123A.

  Since such a rubber pad 140 is provided on the bracket 110, when the rotary shaft 123A moves while rolling in the width direction in the guide hole 111, it receives frictional resistance from the rubber pad 140, so that the guide hole surely does not slip. It is possible to move in 111 to the first position or the second position. In particular, as described above, when the guide hole 111 is formed in an arc shape that is substantially concentric with the pitch circle of the drive gear 122, the arc surface 111C is inclined upward from the end surfaces 111A and 111B. If the rubber pad 140 is not provided, slipping is likely to occur. However, since the rubber pad 140 is provided on the arc surface 111C as described above, even if the guide hole 111 is inclined upward toward the end surfaces 111A and 111B, the rotating shaft 123A is provided. Can reliably move to the first position or the second position.

  In the above-described embodiment, the example in which the rubber pad 140 is provided on the lower circular arc surface 111C of the guide hole 111 has been described, but the present invention is not limited to such a configuration. For example, as shown in FIG. 10, in addition to the rubber pad 140, a spring member 145 (an example of a load member, an urging member, and an elastic member) that urges the rotating shaft 123A downward may be provided. The spring member 145 is an elastic member such as a coil spring, for example. One end of the spring member 145 is inserted into the mounting hole 110E of the bracket 110, and the other end is supported by a support portion (not shown) in a state where the spring member 145 is compressed. A cylindrical bush member 146 made of polyacetal resin is provided between the spring member 145 and the rotary shaft 123A so as not to inhibit the rotation of the rotary shaft 123A. The spring member 145 urges the rotating shaft 123 </ b> A downward via the bush member 146. As a result, the spring member 145 elastically biases the rotating shaft 123A downward, thereby applying a load between the rubber pad 140 on the arc surface 111C and the rotating shaft 123A. With such a configuration, it is possible to generate a larger frictional resistance on the peripheral surface of the rotating shaft 123A with respect to the moving direction of the rotating shaft 123A. As a result, the rotating shaft 123A reliably slides in the guide hole without slipping. It is possible to move in 111 to the first position or the second position.

  Note that both the rubber pad 140 and the spring member 145 need not be provided on the bracket 110, and at least one of them may be provided on the bracket 110.

10: Image processing device 14: Image forming unit 27, 28: Paper feeding device 101: Drive device 102: Housing 105: First output unit 106: Second output unit 110: Bracket 111: Guide hole 112: Flange unit 121: Motor 122: Drive gear 123: Moving gear 123A: Rotating shaft 124: First gear portion 126: Second gear portion 128: Idle gear 131, 132: Transmission gear 140: Rubber pad 145: Spring member

Claims (5)

A drive device for switching the rotational speed of the drive output unit,
A drive source for supplying rotational driving force;
A drive gear arranged to be rotatable in a first direction and a second direction in accordance with forward and reverse rotation of the drive source;
A moving gear arranged to mesh with the driving gear and configured to be movable between a first position and a second position by the rotational driving force transmitted from the driving gear;
A first drive transmission unit that meshes with the movement gear and transmits the rotational driving force to the drive output unit when the movement gear swings to the first position as the drive gear rotates in the first direction. When,
When the moving gear swings to the second position by rotating the driving gear in the second direction, the driving gear meshes with the moving gear, and the rotational driving force with a different reduction ratio with respect to the first drive transmission unit. A second drive transmission section for transmitting the drive output section to the drive output section;
A bracket having a support hole for guiding the moving gear to the first position and the second position by supporting the rotating shaft of the moving gear so as to be movable sideways and rotatably;
The bracket may have a load member burdening between the support surface of said rotary shaft in said support hole and said rotary shaft,
It said load member has an elastic member der Ru driving device for resiliently biased toward the rotational axis to the support surface of the support hole. The support hole, the driving device according to claim 1, which is formed in an arcuate shape to draw a pitch circle substantially concentric of the drive gear. The drive device according to claim 2 , wherein the support hole supports the rotating shaft below the drive gear. Sheet conveying apparatus comprising a driving device according to any one of claims 1 to 3. Image forming apparatus including a driving apparatus according to any one of claims 1 to 3.

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