JP2001228665A - Attaching structure for torque transmitting member and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attach a torque transmitting member provided at a coupling part between a photoreceptor drum and a motor output shaft by extremely easy operation without using a special part such as a snap ring in structure for attaching the torque transmitting member to the motor output shaft. SOLUTION: An engaging projection 3 is formed on the inner peripheral surface of the hole 1a of the torque transmitting member 1 in which the motor output shaft 11 is fit. A notched part 11c in an axial direction where the projection 3 can pass from its edge side, a notched part 11b in a peripheral direction where the projection 3 passing through the notched part 11c can be moved and rotated, and an engaging groove 11d having specified length in the axial direction in which the projection 3 moved and rotated by 180 deg. in the notched part 11b can be engaged by the energizing of a spring member 12 are formed on the shaft 11. Thus, the member 1 is attached to the shaft 11 by the extremely easy operation, that is, just by relatively moving and rotating the member 1, and the special part such as the snap ring need not be used. Namely, the attaching work is simplified and the number of parts is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure of a torque transmitting member provided at a connecting portion between a photosensitive drum and a motor output shaft in, for example, an image forming apparatus. A torque transmitting member provided between a second shaft coaxially and rotatably provided on a first shaft, the torque transmitting member always rotating integrally with the first shaft, and a torque transmitting member provided on the first shaft. On the other hand, by sliding in the direction of the central axis, the second shaft is disengaged from the second shaft, and the rotation of the first shaft is transmitted to or cut off from the second shaft to the first shaft. Mounting structure.

[0002]

2. Description of the Related Art For example, in an image forming apparatus in which a photosensitive drum is directly driven by a motor, a torque transmitting member for transmitting the rotation of the output shaft to the photosensitive drum on an output shaft of the motor. Is attached. FIG. 2 shows a conventional example of a connecting portion between the motor output shaft 74 and the photosensitive drum 28. The motor output shaft 74 includes a torque transmitting member 7.
0 is attached. As shown in FIG. 3, a groove 98 is formed on the torque transmitting member 70 on the side of the fitting surface with the motor output shaft 74, and this groove 98 is engaged with an engagement pin 100 fixed to the motor output shaft 74. I agree. Thus, the torque transmitting member 70 can rotate integrally with the motor output shaft 74 and can slide in the axial direction. Further, the end face 74 of the large diameter portion 74a of the motor output shaft 74
A spring member 97 is interposed between b and the end face 70b of the torque transmitting member 70, and constantly biases the torque transmitting member 70 toward the photosensitive drum 28 side. The motor output shaft 74 has a retaining ring 10 for regulating the axial position of the torque transmitting member 70 urged by the spring member 97.
4 is attached. As shown in FIG. 4, a plurality of projections 102 are formed on the surface 70a of the torque transmission member 70 on the side facing the photosensitive drum 28 so as to engage with the engaging grooves 101 of the photosensitive drum 28. . By engaging the tip 74c of the motor output shaft with the shaft hole 103 of the photosensitive drum 28 and engaging the projection 102 of the torque transmitting member 70 with the engaging groove 101 of the photosensitive drum 28,
The torque of the motor output shaft 74 is transmitted to the photosensitive drum 28 via the torque transmitting member 70. The engagement between the torque transmitting member 70 and the photosensitive drum 28 is established by sliding the torque transmitting member 70 in the axial direction of the motor output shaft 74 against the spring force of the spring member 97. By releasing, the transmission of torque between the motor output shaft 74 and the photosensitive drum 28 can be interrupted. Here, when attaching the torque transmitting member 70 according to the conventional example to the motor output shaft 74, the motor output shaft 74 to which only the spring member 97 and the engagement pin 100 are attached is attached.
Then, the torque transmitting member 70 is pushed in against the urging force of the spring member 97, and the motor output shaft 74 is further pressed in that state.
, It was necessary to attach the retaining ring 104.

[0003]

However, the above-mentioned method of mounting the torque transmitting member using the retaining ring not only requires a great deal of time to mount the motor on the output shaft but also removes the motor. There was also a problem that the score increased. The present invention has been made in view of the above circumstances, and an object of the present invention is to attach a torque transmitting member to a shaft with a small number of parts and by a very simple operation. Is to provide a structure.

[0004]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention comprises a first shaft and a second shaft provided coaxially and rotatably with the first shaft. A torque transmitting member, which always rotates integrally with the first shaft, and is disengaged from the second shaft by sliding with respect to the first shaft in the direction of its central axis, In the mounting structure of the torque transmitting member for transmitting or blocking the rotation of the first shaft to the second shaft to the first shaft, the first shaft of the torque transmitting member is rotatably fitted. An engagement projection is provided on the inner peripheral surface of the hole, and the first shaft has a first notch in the axial direction through which the engagement projection can pass from a tip end thereof, and the first notch. A second notch in the circumferential direction in which the engaging protrusion that has passed through is rotatable, and a second notch in the circumferential direction. A third notch having a predetermined length in the axial direction that can be engaged with the rolling engagement of the engagement protrusion by sliding the torque transmission member toward the shaft tip of the first shaft is formed. It is configured as a mounting structure of a characteristic torque transmitting member. According to the mounting structure of the torque transmitting member, it is possible to mount the torque transmitting member by an extremely simple operation of moving and rotating the torque transmitting member relative to the first shaft. There is no need to use That is, the mounting operation can be simplified and the number of parts can be reduced. The mounting structure of the torque transmitting member is applicable to, for example, an image forming apparatus in which the first shaft is connected to a drive source and the second shaft is connected to a photosensitive drum or its rotating shaft. .

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments and examples of the present invention will be described below with reference to the accompanying drawings to provide an understanding of the present invention. The following embodiments and examples are examples embodying the present invention, and do not limit the technical scope of the present invention. Here, FIG. 1 is a diagram showing a mounting structure and a mounting procedure of a torque transmitting member to a motor output shaft according to an embodiment of the present invention. In this embodiment,
The mounting structure of the torque transmitting member according to the present invention is the same as that of the conventional example described above, except that the motor output shaft of the torque transmitting member provided between the photosensitive drum of the image forming apparatus and the output shaft of the motor for driving the same. It is embodied as a structure for attaching to a vehicle, and has a schematic configuration as shown in FIG.

As shown in FIG. 1, a torque transmitting member 1 according to the present embodiment is formed in a ring shape having a through hole 1a in which a motor output shaft 11 (an example of a first shaft) is fitted at the center. Have been. The engaging surface 1b of the torque transmitting member 1 with the photosensitive drum 21 (an example of a second shaft) has a height L1 capable of engaging with the engaging groove 22 of the photosensitive drum 21.
Four projections 2 are attached. Further, an engagement protrusion 3 is formed on the inner peripheral surface of the through hole 1a. The motor output shaft 11 has a large-diameter portion 1 on the distal end side.
A small diameter portion 11b (an example of a second notch) is formed adjacent to 1a. The large diameter portion 11a and the through hole 1a of the torque transmitting member 1 have substantially the same diameter, and the small diameter portion 11b
Is formed to have a diameter substantially the same as or slightly smaller than the radius of the through hole 1a at the position of the engagement protrusion 3. Further, in the large-diameter portion 11a, a through hole 1 of the torque transmitting member 1 is provided.
A notch 11c (an example of a first notch) through which the engaging projection 3 can pass when fitted to a is formed over the entire length in the axial direction. Further, an engagement groove 11d (an example of a third notch) having an axial length L2 with which the engagement protrusion 3 can be engaged is provided at a circumferential position of the large diameter portion 11a opposite to the notch 11c. Are formed adjacent to the small diameter portion 11b.

Next, a procedure for attaching the torque transmitting member 1 to the motor output shaft 11 will be described with reference to FIG. Prior to mounting the torque transmitting member 1,
First, a spring member 12 is fitted into the motor output shaft 11 so as to contact the end face 11e of the small diameter portion 11b.
Then, the torque transmitting member 1 is fitted straight into the motor output shaft 11 in a state where the engaging projections 3 of the torque transmitting member 1 and the cutout portions 11c of the motor output shaft 11 are aligned. (FIG. 1 (a)). During the fitting, the surface 1c of the torque transmitting member 1 and the spring member 12 come into contact with each other. Is pushed further until the engaging projection 3 reaches the small diameter portion 11b against the urging force. Then, in this state, the torque transmitting member 1 is rotated by 180 ° relative to the motor output shaft 11 so that the engaging projection 3 and the engaging groove 11d are aligned (FIG. 1).
(B)). Here, when the force applied to the torque transmitting member 1 against the spring member 12 is relaxed, the torque transmitting member 1 is moved toward the distal end of the motor output shaft 11 by the urging force of the spring member 12. Thereby, the engaging projection 3 and the engaging groove 11d are engaged.

As described above, the engagement between the engagement projection 3 and the engagement groove 11d allows the rotation of the torque transmission member 1 and the rotation of the motor output shaft 11 to be integrated. The torque transmitting member 1 is connected to the motor output shaft 1 by the spring member 12.
1, the engagement between the engagement protrusion 3 and the engagement groove 11 d is not easily released. In this state, the tip 11 of the motor output shaft 11
f into the center hole 21a of the photosensitive drum 21,
Further, if the projection 2 of the torque transmitting member 1 is engaged with the engaging groove 22 of the photosensitive drum 21, the rotation of the torque transmitting member 1 and the photosensitive drum 21 is integrated (see FIG. c)). That is, the rotation of the motor output shaft 11 can be transmitted to the photosensitive drum 21 via the torque transmitting member 1. The torque transmitting member 1 is moved from the state shown in FIG.
When the projection 2 of the torque transmitting member 1 is disengaged from the engaging groove 22 of the photosensitive drum 21 when the torque transmitting member 1 and the photosensitive drum 21 are disengaged. The transmission of rotation with is interrupted. Here, the projection 2 of the torque transmitting member 1 and the engagement groove 2 of the photosensitive drum 21
2 so that the engagement projection 3 of the torque transmission member 1 and the engagement groove 11d of the motor output shaft 11 are not released even if the engagement with the projection 2 of the torque transmission member 1 is released. L
The relationship between 1 and the axial length L2 of the engagement groove 11d of the motor output shaft 11 needs to be L1 <L2.

As described above, in the torque transmitting member mounting structure according to the present embodiment, the torque transmitting member 1 is moved relative to the motor output shaft 11 without using a separate component such as a retaining ring. It can be mounted by a very simple operation just by rotating.

[0010]

In the above embodiment, the mounting structure of the torque transmitting member according to the present invention is the same as that of the above-described motor of the torque transmitting member provided between the photosensitive drum of the image forming apparatus and the output shaft of the motor for driving the photosensitive drum. Although an example has been described in which the present invention is embodied as a structure for mounting to an output shaft, it is needless to say that the present invention can be applied to other driving force transmitting portions of an image forming apparatus and further to other devices.

[0011]

As described above, the present invention relates to a torque transmission member provided between a first shaft and a second shaft rotatably provided coaxially with the first shaft. And the first
The shaft always rotates integrally with the first shaft, and slides in the direction of the central axis with respect to the first shaft to disengage with the second shaft and rotate the first shaft in the second shaft. In the mounting structure of the torque transmitting member for transmitting or interrupting to the first shaft to the first shaft, an engagement projection is provided on an inner peripheral surface of a hole in which the first shaft of the torque transmitting member is rotatably fitted. The first shaft has a first notch in the axial direction through which the engaging protrusion can pass from a tip end thereof, and the engaging protrusion having passed through the first notch is rotatable. The second notch in the circumferential direction and the engaging protrusion which has been rotated by a predetermined amount in the second notch are connected to the first notch of the torque transmitting member.
And a third notch having a predetermined length in the axial direction which can be engaged by sliding the shaft in the direction of the shaft tip. It is possible to mount the torque transmitting member by a very simple operation of merely moving and rotating the torque transmitting member relative to the first shaft, and it is not necessary to use another component such as a retaining ring. That is, the mounting operation can be simplified and the number of parts can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing a mounting structure and a mounting procedure of a torque transmitting member to a motor output shaft according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a structure for mounting a torque transmission member 70 to a motor output shaft 74 according to a conventional example.

FIG. 3 is a rear view of a torque transmission member 70 according to a conventional example.

FIG. 4 is a perspective view showing an engagement portion between a torque transmission member 70 and a photosensitive drum 28 according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Torque transmission member 1a ... Hole 2 ... Projection 3 ... Engagement projection 11 ... Motor output shaft (an example of a 1st shaft) 11a ... Large diameter part 11b ... Small diameter part (an example of a 2nd notch) 11c ... Notch Part (an example of a first notch) 11d ... an engagement groove (an example of a third notch) 12 ... a spring member 21 ... a photosensitive drum (an example of a second shaft) 21a ... a center hole 22 ... an engagement groove

Claims (2)

[Claims] 1. A torque transmission member provided between a first shaft and a second shaft rotatably provided coaxially with the first shaft, wherein the torque transmission member is provided at all times with the first shaft. While rotating integrally, it slides in the direction of the center axis with respect to the first shaft so as to be disengaged from the second shaft and transmit the rotation of the first shaft to the second shaft. Alternatively, in the mounting structure of the torque transmitting member to be cut off to the first shaft, an engagement projection is provided on an inner peripheral surface of a hole in which the first shaft of the torque transmitting member is rotatably fitted. The first shaft has a first notch in the axial direction through which the engagement protrusion can pass from the tip end thereof, and a circumferential notch in which the engagement protrusion has passed through the first notch and can rotate. A second notch portion and the engagement protrusion which has rotated the second notch portion by a predetermined amount are provided on the torque transmitting member. 3. A mounting structure for a torque transmitting member, comprising: a third notch having a predetermined length in an axial direction that can be engaged by sliding a first shaft in a shaft tip direction. 2. A torque transmission member mounting structure according to claim 1, wherein said first shaft is connected to a drive source, and said second shaft is connected to a photosensitive drum or its rotating shaft. Image forming apparatus.