JP2009019716A - Drive transmission device and image-forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drive transmission device and an image-forming device wherein durability is improved by relaxing an impact made in the rotative direction at the time of shifting from a non-interlocking state to an interlocking state. <P>SOLUTION: In a clutch device, an interlocking state between a rotatable first-docking-gear which is axially fixed to a bearing shaft and a rotatable second-docking-gear which is axially slidable with respect to the bearing shaft is shifted by sliding the second docking-gear through a coupling member by means of an axial cam provided in a cam wheel placed on the second docking-gear side. One end of a guide pin 4 is inserted in a pin-hole made in the bearing shaft, and the other end is positioned in the guide groove formed in the coupling member to inhibit the coupling member from rotating. In the guide pin 4, first and second sliding faces 42, 43 having finite length respectively are provided to the head 41 at the other end in contact with both inner walls of the guide groove so that the impact is dispersed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image forming apparatus and a drive transmission device to a rotating body such as a photosensitive drum. More specifically, the present invention relates to a drive transmission device capable of switching between a state in which drive is transmitted from a drive source to a rotating body and a state in which drive is not transmitted, and an image forming apparatus using the drive transmission device. In particular, the driving of a plurality of rotating bodies such as a photosensitive drum and a developing roller is provided by a single driving source, and the state of transmission to one rotating body (developing roller, etc.) and the state of not transmitting are switched depending on the situation. It is suitable for use in an image forming apparatus.

  Conventionally, an image forming apparatus has a large number of rotating bodies such as a photosensitive drum and a developing roller. The timing at which these are driven to rotate varies depending on the difference in their functions. However, if one dedicated drive source is provided for each, there is a problem in cost and apparatus configuration. Therefore, it is conceivable to drive a plurality of rotating bodies with a single drive source. For this purpose, a drive transmission device capable of switching between a state in which drive is transmitted from the drive source to the rotating body and a state in which the drive is not transmitted is required. This is because the drive source may be rotating for another rotating body even when the rotating body should be stopped.

Patent Document 1 describes an example of such a drive transmission device. The mechanical clutch of the drive device of the document has a drive side engaging part and a driven side engaging part. Then, by moving the driven side engaging component in the axial direction, the connected state where both engaging components are engaged with each other and the unconnected state where the engagement is released are switched. In this mechanical clutch, a groove is further provided on the inner peripheral surface of the driven side engaging component. A parallel pin is fixedly provided on the rotation shaft. This parallel pin is fitted in the groove of the driven side engaging component. As a result, the driven-side engaging component can be slid in the axial direction with respect to the rotating shaft, and is fixed in the rotating direction.
Japanese Patent Laid-Open No. 2003-208024

  However, the above-described conventional drive transmission device has the following problems. That is, it is vulnerable to an impact when switching from the unconnected state to the connected state. Naturally, in such a clutch mechanism, a certain amount of impact is applied when switching from the unconnected state to the connected state. The impact includes an axial component and a rotational component. In the mechanical clutch of Patent Document 1, it is considered that the impact in the axial direction is relaxed to some extent by the coil spring. However, with respect to the rotation direction, an impact is applied between the parallel pin and the groove on the inner peripheral surface of the driven side engaging component. In addition, the contact between the two is actually a line contact (point contact when viewed from the tip of the parallel pin toward the center of the rotation axis). For this reason, since the impact is concentrated on one place, the groove portion of the driven side engaging component may be damaged by repeated impact.

  The present invention has been made to solve the above-described problems of the prior art. That is, an object of the present invention is to provide a drive transmission device and an image forming apparatus using the drive transmission device that have improved the durability by mitigating the impact in the rotational direction when switching from the unconnected state to the connected state. .

  In order to solve this problem, a drive transmission device for an image forming apparatus according to the present invention is provided with a support shaft having a pin hole formed in a side portion, and a shaft fixed to the support shaft and rotatable. A first gear that is provided, a second gear that is slidable and rotatable in the axial direction with respect to the support shaft, and is located on the opposite side of the first gear as viewed from the second gear. On the other hand, it is fixed in the axial direction and is rotatably provided. The cam wheel having an axial cam portion that slides the second gear in the axial direction by the rotation, and the second gear and the cam wheel are positioned and supported. A connecting member that is slidably attached to the shaft in the axial direction, has an end on the cam wheel side that is in contact with the axial cam portion, and a guide groove that is parallel to the axial direction is formed on the surface on the support shaft side. It is inserted into the pin hole of the support shaft and the other end is in the guide groove. In the state where the second gear is slid in the direction approaching the first gear, the first gear and the second gear come into contact with each other and rotate integrally. Thus, rotation is transmitted from the drive source to the driven part via the first gear and the second gear, and when the second gear is slid away from the first gear, the drive source to the driven part is A drive transmission device for blocking transmission of rotation, wherein a first slide portion and a second slide portion that are in contact with both inner wall surfaces of the guide groove and have a finite length in the axial direction are formed at the other end of the guide pin. It is what has been.

  In the drive transmission device of this image forming apparatus, when the second gear is away from the first gear, the rotations of both gears are independent of each other. For this reason, rotation is not transmitted from the drive source to the driven part via both gears. In a state where the second gear is slid in the direction approaching the first gear, the first gear and the second gear come into contact with each other and rotate integrally, so that the drive source is connected via the first gear and the second gear. The rotation is transmitted to the driven part. The sliding movement of the second gear is performed by the cam member rotating through the axial cam portion pushing the connecting member. Here, the rotation of the connecting member is prevented by interference between the first slide portion and the second slide portion of the guide pin and both inner wall surfaces of the guide groove of the connecting member.

  An impact is applied to the contact portion between the first slide portion and the second slide portion and the inner wall surface particularly when switching from the non-transmission state to the transmission state. However, since the first slide portion and the second slide portion have a finite length in the axial direction, these contact portions are in surface contact. For this reason, the impact is alleviated without being concentrated in one place. Therefore, even if switching is repeated, there is no damage at the contact point and the service life is long.

  Here, a first meshing claw is formed on the second gear side end surface of the first gear, a second meshing claw is formed on the first gear side end surface of the second gear, and the second gear is the first gear. The first meshing claw and the second meshing claw mesh with each other when sliding in the direction approaching the gear, and the first meshing claw and the second meshing claw when sliding with the second gear sliding away from the first gear. It is desirable to disengage from.

  If it is such, rotation transmission in a transmission state is more reliable by meshing of both meshing claws. On the other hand, since the impact at the time of switching is large, the significance of impact dispersion by the first slide portion and the second slide portion is greater.

  In addition, the present invention is applied to an image forming apparatus, wherein a first gear is a gear that transmits rotational driving to a developing roller, and a second gear is a gear that receives rotational driving from a photoconductor drive source of the image forming apparatus. It is preferable to be. In this case, since the developing roller does not always rotate, it is appropriate to intermittently transmit the rotation from the photoconductor drive source by the drive transmission device of the present invention.

  Moreover, it is desirable that worm gear teeth that are driven from the cam driving motor via the worm are formed on the peripheral surface of the cam wheel of the present invention. Thereby, the cam wheel can be driven separately from the drive to the driven part via the first gear and the second gear.

  The present invention extends to an image forming apparatus that uses the drive transmission device described above, shares the drive source for the photosensitive member with the drive of the developing roller, and transmits the rotational drive from the second gear to the developing roller.

  According to the present invention, there are provided a drive transmission device and an image forming apparatus using the drive transmission device which have improved durability by mitigating the impact in the rotational direction applied when switching from the unconnected state to the connected state.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the best mode for embodying the present invention will be described in detail with reference to the accompanying drawings. The drive transmission system of the image forming apparatus according to this embodiment is configured as shown in FIG. FIG. 1 shows a drive transmission system to the photosensitive drum and developing roller for the three colors Y (yellow), M (magenta), and C (cyan) in the tandem four-color image forming apparatus.

  The image forming apparatus in FIG. 1 includes photosensitive drums 80Y, 80M, and 80C, and developing rollers 81Y, 81M, and 81C. And the motor shaft 82 of the motor which is a drive source of these rotary bodies is provided. The drive transmission system further includes a photosensitive drum series drive shaft 83 and a developing roller series drive shaft 84. The drive is transmitted from the motor shaft 82 to the photosensitive drums 80Y, 80M, and 80C via the photosensitive drum series driving shaft 83. Further, the drive is transmitted from the motor shaft 82 to the developing rollers 81Y, 81M, 81C via the developing roller series driving shaft 84. Although not shown in FIG. 1, the image forming apparatus is also provided with a drive transmission system for a black photosensitive drum and a developing roller.

  The developing roller series drive shaft 84 in FIG. 1 is provided with the clutch device 1 shown in FIGS. 2 is a front view when not connected, FIG. 3 is a front view when connected, and FIG. 4 is an exploded perspective view. The clutch device 1 includes a first docking gear 2, a second docking gear 3, a guide pin 4, a connecting member 5, and a cam wheel 6. The developing roller series drive shaft (hereinafter referred to as “support shaft”) 84 is fixed to the image forming apparatus. A pin hole 85 for inserting the guide pin 4 is formed on the side surface.

  The first docking gear 2 is fixed in the axial direction with respect to the support shaft 84 and is provided to be rotatable. A first meshing claw 20 is formed on one end surface of the first docking gear 2. The first meshing claw 20 is provided on the end surface of the first docking gear 2 on the second docking gear 3 side. The first docking gear 2 is a gear connected to the developing rollers 81Y, 81M, 81C in FIG. 1, and is a driven gear in the clutch device 1.

  The second docking gear 3 can slide in the axial direction with respect to the support shaft 84 and can also rotate. The second docking gear 3 is located on the first meshing claw 20 side when viewed from the first docking gear 2. A second meshing claw 30 is formed on one end surface of the second docking gear 3. The second meshing claw 30 is provided on the end surface of the second docking gear 3 on the first docking gear 2 side. An end surface of the second docking gear 3 opposite to the second meshing claw 30 is a sliding surface 31 that contacts the connecting member 5. The second docking gear 3 is a gear connected to the motor shaft 82 in FIG. 1 and is a drive gear in the clutch device 1.

  In the clutch device 1, the non-connected state of FIG. 2 and the connected state of FIG. 3 can be switched by the sliding movement of the second docking gear 3. That is, the state in which the second docking gear 3 is moved away from the first docking gear 2 is the unconnected state in FIG. In this unconnected state, the first meshing claw 20 and the second meshing claw 30 are not meshed. For this reason, the drive is not transmitted between the first docking gear 2 and the second docking gear 3.

  On the other hand, the state in which the second docking gear 3 moves in a direction approaching the first docking gear 2 is the connected state of FIG. In this connected state, the first meshing claw 20 and the second meshing claw 30 are meshed. For this reason, the first docking gear 2 and the second docking gear 3 can only rotate integrally. That is, the drive is transmitted between the first docking gear 2 and the second docking gear 3.

  The gear teeth of both the first docking gear 2 and the second docking gear 3 are bevel teeth. The direction of the inclined teeth of the second docking gear 3 is set so that the direction of the thrust force is on the connection release side. That is, the thrust force generated by driving from the motor shaft 82 side presses the second docking gear 3 from the connected state of FIG. 3 toward the unconnected state of FIG. However, in FIG. 2 and the like, illustration of gear teeth on the peripheral surface of the first docking gear 2 is omitted.

  The cam wheel 6 is fixed in the axial direction with respect to the support shaft 84 and is provided to be rotatable. The cam wheel 6 is located on the side opposite to the first docking gear 2 when viewed from the second docking gear 3. An axial cam portion 60 is formed at a position around the support shaft 84 on the surface of the cam wheel 6 on the second docking gear 3 side. The axial cam portion 60 is an inclined surface and is a surface on which the second docking gear 3 is slid.

  The cam wheel 6 further has gear teeth 61 and a half moon umbrella 62. The gear teeth 61 are for receiving rotational driving from a driving source. However, the drive source is different from the motor of the motor shaft 82 and is intended only for sliding the second docking gear 3. The gear teeth 61 are usually arranged so as to receive driving from the driving source via a worm. Therefore, the cam wheel 6 is also called a worm wheel.

  The half moon umbrella 62 changes its position as the cam wheel 6 rotates. The semi-moon umbrella unit 62 is for recognizing the rotation angle of the cam wheel 6 by detecting its position in the main body control unit of the image forming apparatus. In other words, the half moon umbrella unit 62 causes the main body control unit to recognize the position of the second docking gear 3.

  The connecting member 5 is a member disposed between the second docking gear 3 and the cam wheel 6. As shown in FIG. 5, the connecting member 5 is a substantially cylindrical member as a whole. The connecting member 5 shown in FIG. 5 has a sleeve portion 50 and a guide groove 52. The inner surface 51 of the sleeve portion 50 is a surface that slidably contacts the side surface of the support shaft 84. The guide groove 52 is formed in parallel with the axial direction of the support shaft 84. Two inner wall surfaces 53 and 54 are formed in the guide groove 52. Naturally, the inner wall surfaces 53 and 54 are parallel to the axial direction of the support shaft 84.

  One end surface 55 of the connecting member 5 is a sliding surface that slidably contacts the sliding surface 31 of the second docking gear 3. The other end surface 56 of the connecting member 5 is a cam surface that slidably contacts the axial cam portion 60 of the cam wheel 6. The cam surface 56 is an inclined surface, and the degree of the inclination is matched with the inclination of the axial cam portion 60.

  As shown in FIG. 6, the guide pin 4 has a hammer-like shape as a whole. The guide pin 4 in FIG. 6 has a pin part 40 and a head part 41. The pin portion 40 is a portion that is inserted into the pin hole 85 of the support shaft 84. The head portion 41 is a portion located in the guide groove 52 of the connecting member 5. Two sliding surfaces 42 and 43 are formed on the head 41. The sliding surfaces 42 and 43 are surfaces that slidably contact the inner wall surfaces 53 and 54 of the guide groove 52. The sliding surfaces 42 and 43 also have a finite length in the direction of arrow X in FIG.

  The assembly of the clutch device 1 is performed as follows. First, the pin portion 40 of the guide pin 4 is inserted into the pin hole 85 of the support shaft 84. Next, the support shaft 84 is inserted into the sleeve portion 50 of the connecting member 5. Then, the head 41 of the guide pin 4 is made parallel to the axial direction of the support shaft 84 and the connecting member 5 is slid to put the head 41 into the guide groove 52. Then, the second docking gear 3 and the cam wheel 6 are attached to both sides of the connecting member 5 in the support shaft 84. Finally, if the first docking gear 2 is attached to the support shaft 84, it is completed.

  In this state, the guide pin 4 is hidden in the connecting member 5 and cannot be seen from the outside. The sliding surfaces 42 and 43 of the head 41 of the guide pin 4 are parallel to the axial direction of the support shaft 84 and have a finite length in that direction. Moreover, the sliding surfaces 42 and 43 and the inner wall surfaces 53 and 54 are slidably in contact. As a result, the connecting member 5 can slide in the axial direction of the support shaft 84, but the rotation is blocked by the interference between the head 41 and the guide groove 52. Here, the contact between the sliding surfaces 42 and 43 and the inner wall surfaces 53 and 54 is surface contact (line contact as shown in FIG. 7 when viewed from the head 41 of the guide pin 4 toward the center of the support shaft 84). It is.

  The clutch device 1 having the above-described configuration operates as follows. First, it is assumed that the clutch device 1 is in the non-connected state shown in FIG. At this time, as described above, the first meshing claw 20 and the second meshing claw 30 are not meshed, and the first docking gear 2 and the second docking gear 3 are in a free state. For this reason, the transmission of the drive from the motor shaft 82 in FIG. 1 stops until the second docking gear 3 and does not reach the first docking gear 2. Therefore, the rotation of the motor shaft 82 is not transmitted to the developing rollers 81Y, 81M, 81C.

  From this state, the cam wheel 6 is rotated. The direction of rotation is a direction in which the axial cam portion 60 of the cam wheel 6 presses the cam surface 56 of the connecting member 5. Here, as described above, the connecting member 5 can only slide and cannot rotate. For this reason, the connecting member 5 is pushed up by the axial cam portion 60 and slides upward in FIG. As the connecting member 5 is raised, the second docking gear 3 is also pushed up. As a result, the first meshing claw 20 and the second meshing claw 30 mesh with each other, and the first docking gear 2 and the second docking gear 3 rotate integrally.

  This state is the connected state of FIG. When this state is reached, the rotation of the cam wheel 6 is stopped. In this state, the rotation of the motor shaft 82 is transmitted to the developing rollers 81Y, 81M, 81C via the clutch device 1. In this state, the sliding surface 55 of the connecting member 5 and the sliding surface 31 of the second docking gear 3 are in contact with each other and are sliding in the rotational direction.

  In the connected state of FIG. 3, as described above, the thrust force due to the inclined teeth acts in a direction to separate the second docking gear 3 from the first docking gear 2. However, such a movement is suppressed because the cam wheel 6 is stopped. As described above, since the cam wheel 6 is coupled to the drive source by the worm, it does not rotate with the thrust force. Further, the position of the half moon umbrella portion 62 of the cam wheel 6 differs between the state of FIG. 2 and the state of FIG. Therefore, the main body control unit of the image forming apparatus can recognize whether the clutch device 1 is in the state shown in FIG. 2 or FIG. 3 by detecting the position of the half moon umbrella unit 62.

  When the cam wheel 6 is rotated in the opposite direction from the state shown in FIG. 3, the axial cam portion 60 moves backward from the cam surface 56 of the connecting member 5. Then, the second docking gear 3 and the connecting member 5 move downward in FIG. 3 by the thrust force of the inclined teeth of the second docking gear 3. As a result, the first meshing claw 20 and the second meshing claw 30 are disengaged from each other, resulting in the unconnected state shown in FIG. When the state shown in FIG. 2 is reached, the rotation of the cam wheel 6 is stopped.

  In the above movement, the connecting member 5 is applied with a torque that tends to rotate in the same direction as the rotation of the second docking gear 3 due to friction with the second docking gear 3. In particular, the torque in the connected state of FIG. 3 is stronger than that in the non-connected state of FIG. This is because the pressure contact force between the connecting member 5 and the second docking gear 3 is stronger in the connected state than in the non-connected state. Actually, as described above, the rotation is prevented by the interference between the head 41 of the guide pin 4 and the guide groove 52 of the connecting member 5.

  The reason why the connecting member 5 is not rotated is because of the cam function of the axial cam portion 60. That is, if the connecting member 5 rotates with the cam wheel 6, the sliding movement of the connecting member 5 and the second docking gear 3 by the axial cam portion 60 cannot be performed. Further, if the connecting member 5 is rotated by the second docking gear 3 while the cam wheel 6 is stopped, the sliding position of the connecting member 5 and the second docking gear 3 is changed by the inclination of the axial cam portion 60. It will change. In particular, when the axial cam portion 60 and the cam surface 56 cross each other, it is conceivable that the connecting member 5 and the second docking gear 3 dance momentarily. In order to prevent these situations, the rotation of the connecting member 5 is prevented.

  On the other hand, the head 41 and the guide groove 52 are always stressed by the above torque when the second docking gear 3 is rotating. In particular, at the moment when the clutch device 1 is switched from the unconnected state in FIG. 2 to the connected state in FIG. 3, the stress rapidly increases and receives an impact. However, in the clutch device 1 of this embodiment, as described above, the sliding surfaces 42 and 43 of the head 41 and the inner wall surfaces 53 and 54 of the guide groove 52 are in surface contact. For this reason, since the impact is received and dispersed by the surface, no specific adverse effect is caused by the impact.

  If the conventional guide pin 9 having no head as shown in FIG. 8 is used instead of the guide pin 4 shown in FIG. 6, the impact is concentrated on one place. This is because the contact between the guide pin 9 and the inner wall surfaces 53 and 54 is a line contact (point contact as shown in FIG. 9 when viewed from the tip of the guide pin 9 in the direction of viewing the center of the rotation axis). For this reason, the part which is contacting the guide pin 9 among the inner wall surfaces 53 and 54 may be damaged by durable use. In this embodiment, such a harmful effect is eliminated by using the guide pin 4 of FIG. Thereby, the clutch apparatus 1 of this embodiment is excellent in durability.

  In general, in the image forming apparatus as shown in FIG. 1, the period during which the developing rollers 81Y, 81M, 81C are to be driven is a part of the period during which the photosensitive drums 80Y, 80M, 80C are to be driven. . That is, as shown in FIG. 10, the photosensitive drum starts to rotate (t1), and then the developing roller starts to rotate (t2). When the rotation is finished, conversely, the rotation of the developing roller is finished first (t3), and then the rotation of the photosensitive drum is finished (t4). Therefore, in the period from t1 to t2 and the period from t3 to t4 in FIG. On the other hand, in the period from t2 to t3, the clutch device 1 is in the connected state of FIG. In the period before t1 and the period after t4, the drive source itself may be stopped.

  As described above in detail, in this embodiment, the guide pin 4 prevents the rotation of the connecting member 5 that transmits the cam action by the axial cam portion 60 of the cam wheel 6 to the second docking gear 3. And the contact location of the guide pin 4 and the connection member 5 which is an impact part at the time of switching was made into the surface contact by the sliding surfaces 42 and 43 and the inner wall surfaces 53 and 54. FIG. As a result, the impact is not concentrated on one place, and each part is not damaged even if switching is repeated. Thus, an image forming apparatus drive transmission device and an image forming apparatus using the same have been realized in which the impact in the rotational direction applied when switching from the non-connected state to the connected state is mitigated to improve durability.

  Note that this embodiment is merely an example, and does not limit the present invention. Therefore, the present invention can naturally be improved and modified in various ways without departing from the gist thereof. Of course, the present invention is not limited to the three-color drive system of Y, M, and C shown in FIG. Therefore, it is naturally applicable not only to color machines but also to monochrome machines.

  For example, the material of each member is not particularly limited, such as resin or metal. Further, the relationship between drive and driven may be switched between the first docking gear 2 and the second docking gear 3. Moreover, if the friction coefficient of the mutual contact surface of the 1st docking gear 2 and the 2nd docking gear 3 is large enough, the 1st meshing claw 20 and the 2nd meshing claw 30 are unnecessary. Further, the guide groove 52 of the connecting member 5 may not be bottomed.

  A compression spring may be provided between the first docking gear 2 and the second docking gear 3. If there is a compression spring, its elasticity acts in the direction of pressing the second docking gear 3 when switching from the connected state of FIG. 3 to the unconnected state of FIG. Thereby, in the above description, the movement of pulling the second docking gear 3 away from the first docking gear 2, which was caused by the thrust force of the inclined teeth of the second docking gear 3, is added. In that case, the gear teeth of the second docking gear 3 may not be inclined teeth.

1 is a configuration diagram illustrating a drive transmission system of an image forming apparatus according to an embodiment. It is a front view which shows the clutch apparatus which concerns on embodiment (at the time of non-connecting). It is a front view (at the time of connection) which shows a clutch device concerning an embodiment. It is a disassembled perspective view which shows the clutch apparatus which concerns on embodiment. It is a see-through | perspective perspective view which shows the connection member in the clutch apparatus which concerns on embodiment. It is a perspective view which shows the guide pin in the clutch apparatus which concerns on embodiment. It is a front view which shows the contact condition of the head part of a guide pin and the groove part of a connection member in the clutch apparatus which concerns on embodiment. It is a perspective view which shows the guide pin in the conventional clutch apparatus. It is a front view which shows the contact condition of the guide pin in the conventional clutch apparatus, and the groove part of a connection member. 6 is a timing chart showing drive timings of the photosensitive drum and the developing roller in the image forming apparatus according to the embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Clutch apparatus 2 1st docking gear 20 1st meshing claw 3 2nd docking gear 30 2nd meshing claw 4 Guide pin 40 Pin part 41 of a guide pin Head parts 42 and 43 of a guide pin 5 Sliding surface 5 of a head Connecting member guide grooves 53 and 54 Guide groove wall surface 56 Connecting member cam surface 6 Cam wheel 60 Axial cam portion 61 Worm gear teeth 80Y etc. Photosensitive drum 81Y etc. Developing roller 82 Motor shaft 84 Support shaft 85 Pin hole

Claims (5)

A support shaft with pin holes formed on the sides,
A first gear fixed in the axial direction with respect to the support shaft and rotatably provided;
A second gear provided so as to be slidable and rotatable in the axial direction with respect to the support shaft;
Located on the opposite side of the first gear from the second gear, is fixed in the axial direction with respect to the support shaft and is rotatably provided, and the second gear is slid in the axial direction by rotation. A cam wheel having an axial cam portion;
Located between the second gear and the cam wheel, is attached to the support shaft so as to be slidable in the axial direction, and the end on the cam wheel side contacts the axial cam portion and is parallel to the axial direction. A connecting member having a guide groove formed on the surface on the support shaft side;
One end is fitted into the pin hole of the support shaft, and the other end is located in the guide groove and has a guide pin for preventing the connection member from rotating.
In a state where the second gear is slid in the direction approaching the first gear, the first gear and the second gear are rotated in contact with each other, so that the first gear and the second gear are rotated. Rotation is transmitted from the drive source to the driven part via
In the state where the second gear is slid in a direction away from the first gear, in the drive transmission device that blocks transmission of rotation from the drive source to the driven part,
A drive transmission device, wherein the other end of the guide pin is formed with a first slide portion and a second slide portion that are in contact with both inner wall surfaces of the guide groove and have a finite length in the axial direction. The drive transmission device according to claim 1,
A first meshing claw is formed on an end surface of the first gear on the second gear side,
A second meshing claw is formed on an end surface of the second gear on the first gear side;
In a state where the second gear is slid in the direction approaching the first gear, the first meshing claw and the second meshing claw mesh with each other,
The drive transmission device according to claim 1, wherein the first meshing claw and the second meshing claw are disengaged when the second gear is slid in a direction away from the first gear. The drive transmission device according to claim 1 or 2,
The first gear is a gear for transmitting rotational driving to the developing roller of the image forming apparatus;
The drive transmission device, wherein the second gear is a gear that receives rotational driving from a driving source for a photosensitive member of the image forming apparatus. In the drive transmission device according to any one of claims 1 to 3,
A drive transmission device characterized in that worm gear teeth that receive driving from a cam drive source via a worm are formed on a peripheral surface of the cam wheel. A support shaft with pin holes formed on the sides,
A first gear fixed in the axial direction with respect to the support shaft and rotatably provided;
A second gear provided so as to be slidable and rotatable in the axial direction with respect to the support shaft;
Located on the opposite side of the first gear from the second gear, is fixed in the axial direction with respect to the support shaft and is rotatably provided, and the second gear is slid in the axial direction by rotation. A cam wheel having an axial cam portion;
Located between the second gear and the cam wheel, is attached to the support shaft so as to be slidable in the axial direction, and the end on the cam wheel side is in contact with the axial cam portion and parallel to the axial direction. A connecting member having a guide groove formed on the surface on the support shaft side;
A guide pin having one end fitted into the pin hole of the support shaft and the other end positioned in the guide groove to prevent rotation of the connecting member;
A developing roller that receives rotational drive from the second gear;
A photoreceptor,
A drive source for rotationally driving the first gear and the photosensitive member;
In a state where the second gear is slid in the direction approaching the first gear, the first gear and the second gear are rotated in contact with each other, whereby the first gear and the second gear are rotated. The rotation from the drive source to the developing roller via
In an image forming apparatus that blocks transmission of rotation from the drive source to the developing roller in a state where the second gear slides away from the first gear,
An image forming apparatus, wherein a first slide portion and a second slide portion that are in contact with both inner wall surfaces of the guide groove and have a finite length in the axial direction are formed at the other end of the guide pin.

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