JP2002005269A - Drive power transmission unit and drives - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drive power transmission unit, wherein the housing can be coupled and decoupled without any constraint in the processing steps of the coupling and decoupling in the case where a fixed shaft and a rotatably shaft obtainable of its inserted or retracted states are disposed in a mingled way in the housing that forms the transmission unit, and the transmission unit is equipped with a setup preventing parts equipped on the housing from dropping out. SOLUTION: The drive power transmission unit 1 has the housing 1A, one face of which is open and the bottom face of which opposing the open face has a base supporting rotatably a plurality of gears. The setup for receiving and supporting the rotatably shaft 3 that form a rotation transmitting part, apart from the fixed shaft 1B formed integrally with the housing 1A, comprises a stop ring 3A put on the rotatably shaft and a preventing means disposed near the drive power transmission means 8 mounted on the rotatable shaft 3. The preventing means prevents the shaft 3 from traveling in the direction opposite to that of the stop ring 3A and prevents the shaft 3 from moving to. Thus the setup of the unit features preventing the rotating shaft from dropping out regardless of the direction of the open face of the housing 1A.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving force transmitting unit and a driving device, and more particularly, to a supporting structure of a driving force transmitting member.

[0002]

2. Description of the Related Art There are various mechanisms for transmitting a driving force from a driving source such as a motor to a driven member. For example, there is a configuration in which a roller or other driven member located on the output side is driven via a transmission gear meshing with a gear provided on an output shaft of a motor or a reduction or speed increasing gear group. Conventionally, a group of gears arranged on a transmission path on the way from a driving source to a driven member is often provided at a necessary position in an apparatus housing, however, in recent years, housings have been considered in consideration of assembly workability. There is a case where the housing is attached to the apparatus housing part by being collectively provided in a unit using. In a housing used as a unit, there is a configuration in which a support shaft for supporting a gear on a bottom plate side by opening a surface attached to an apparatus housing side is available. In this configuration, the support shaft is integrally formed with the housing, thereby reducing the man-hour for mounting the support shaft. When a gear is installed in a housing in which a support shaft is integrally formed, the gear is inserted into the support shaft, an E-shaped retaining ring is attached to the support shaft, and the gear is rotated. Support freely.

FIG. 8 and FIG. 9 are views showing an example in which gears are provided on a housing in which a support shaft is integrally formed. Each gear is inserted into a housing A having an open surface. Possible support shafts A1 to A9 are integrated in an upright state in advance, and gears B1 to B9 are inserted into these support shafts A1 to A9, respectively. One surface of the opened housing A is a surface facing the device housing side, and corresponds to a side on the device housing side that can transmit a driving force to a power transmission unit.

The housing A has a gear B1 on the bottom surface.
A motor C, which is a drive source, is attached to the back surface opposite to the side where B9 to B9 are inserted (see FIG. 9), and a gear provided on the output shaft of the motor C is used as a drive side for each gear. Driving force is transmitted. In many cases, the housing A in which the support shaft is integrally formed in advance is detachably mounted on a driving unit of the apparatus main body (not shown) using a fastening member or the like.

In order to transmit the driving force from the drive source to the driven member, unlike the case where the support shafts of all the gears are integrally formed in advance in the housing described above, some of the support shafts are formed in the housing A depending on the specifications of the mechanism. There is a case where it is provided rotatably with respect to. In such a case, the case where the support shaft of the gear itself is used as the driving force transmitting member corresponds. That is, when it is assumed that the support shaft of the gear is interlocked with another rotatable support shaft via a clutch or a coupling member, the corresponding support shaft is supported among the support shafts supported by the housing. The shaft needs to be supported so that it can rotate independently of housing A.

In the case of a support shaft rotatable independently of the housing, that is, a so-called rotary support shaft, the housing is mounted so that the rotary support shaft inserted into the bottom surface of the housing can be connected to the rotary shaft on the apparatus housing side. When the housing is attached to the device housing, when the housing needs to be removed from the device housing, only the rotation support shaft may remain on the device housing side when the housing is removed. FIG. 10 is a view showing this case. When the housing A is detached from the device housing D, the rotation support shaft (indicated by the symbol RS for convenience) inserted and supported on the device housing D side is the same as the housing A. It may fall out of the insertion support portion and remain on the device housing D side as it is. Such a phenomenon is often caused by the structure of the support portion of the rotating shaft on the housing A side and the device housing D side. That is, the rotation support shaft R provided on the device housing D side
In the case where S is supported on the insertion supporting portion D1 via the bearing E, the frictional force at the location where the bearing E is press-fitted is larger than the frictional force on the rotary support shaft RS. Is removed from the device housing D, the rotary support shaft RS remains on the device housing D together with the bearing E.

Conventionally, the following procedure has been performed when assembling a housing of this type to an apparatus housing. First, the rotation support shaft RS is supported together with the bearing E on the insertion support portion D1 of the device housing D in advance. Since the rotation support shaft RS is located on the device housing side, the rotation support shaft RS is inserted into the insertion support portion of the housing A. For this reason, the slide bearing S is mounted on the insertion support portion of the housing A, and the slide bearing S has a flange S1 on the inner surface side of the housing A corresponding to the upstream side in the insertion direction of the rotation support shaft RS. This prevents the inserted rotary support shaft from falling off the insertion support portion.

A gear, which is a driving force transmitting means, is mounted on another support shaft integrally formed with the housing A, and finally, the housing A and the device housing D are integrally mounted by fastening or the like. At this time, the rotation support shaft RS is inserted into the slide bearing of the housing A.

[0009]

In a conventional driving force transmission unit, when a housing is provided with a supporting shaft that rotates independently of the housing, separately from the supporting shaft integrally formed with the housing, the housing is required to be provided. There is a problem that a process procedure when attaching and detaching the device to and from the device housing is restricted. As a result, since assembly and removal of the drive transmission means cannot be performed only for the housing, it is possible to simplify the work procedure by enabling the work to be performed in a small number of places, which is the initial purpose of the unit. It becomes difficult to plan.

[0010] In the housing, drive transmission means is provided for each support shaft or rotary support shaft.
As described above, the driving force transmission means provided on the rotating shaft that can be inserted into and removed from the housing may fall off depending on the direction of the open surface of the housing, and may cause a problem such as loss of parts.

SUMMARY OF THE INVENTION In view of the above-mentioned problems in the conventional driving force transmission unit and the driving device, an object of the present invention is to provide a stationary support shaft and a rotatable support shaft capable of being inserted and removed in a housing constituting the unit. When provided in a mixed manner, the housing can be easily attached / detached without any restriction on the process procedure for attaching / detaching the housing, and the components mounted on the housing can be dropped, particularly, the housing can be inserted / removed. It is an object of the present invention to provide a driving force transmission unit and a driving device having a configuration capable of preventing the rotation support shafts from falling off.

[0012]

According to the first aspect of the present invention,
A driving force transmission unit including a housing having one surface opened and a support provided on a bottom plate for rotatably supporting a plurality of gears, wherein the support shaft has a support shaft of the gear integrally formed with the housing in advance. And a configuration for rotatably supporting the support shaft independently of the housing, wherein the support shaft is rotatably formed on the bottom surface of the housing as a configuration for rotatably supporting the support shaft. And a restricting means provided in the vicinity of the insertion part for restricting movement of the rotatable support shaft in one axial direction, wherein the restricting means comprises a rotatable support. It is disposed close to and opposed to the driving force transmitting means mounted on the shaft, and is mounted on the shaft end of the rotatable support shaft to restrict the movement of the support shaft in the other axial direction. Retaining ring and the restricting means In is characterized in that said rotatable support shaft to restrict the movement to one of the axial direction.

According to a second aspect of the present invention, in the driving force transmitting unit according to the first aspect, the restricting means is formed as a single piece integrally formed on an inner surface of the housing and protruding near the driving force transmitting means. It is characterized by being.

According to a third aspect of the present invention, in the driving force transmitting unit according to the first aspect, the driving force transmitting means provided on the rotatable support shaft is a helical gear, and the helical gear is provided. It is characterized in that the torsional direction of the gear teeth is set to a torsional direction that generates a moving force in a direction away from the regulating means at the time of meshing.

According to a fourth aspect of the present invention, in the driving force transmitting unit according to any one of the first to third aspects, the insertion portion provided in the housing has a bearing of the rotatable support shaft. Is provided.

According to a fifth aspect of the present invention, in the driving force transmission unit according to the fourth aspect, the press-fit holding portion is constituted by a convex portion formed on a part of the inner surface of the insertion portion. Is characterized in that it can be compressed and deformed by inserting a bearing that supports the rotatable support shaft.

According to a sixth aspect of the present invention, in the driving force transmitting unit according to any one of the first to fifth aspects, the driving force transmitting means mounted on the rotatable support shaft is provided with another support. An arrangement is provided in which at least one of the driving force transmitting means provided on the rotatable support shaft among the driving force transmitting means provided on the shaft is not moved to one open side of the housing. And

According to a seventh aspect of the present invention, in the driving force transmitting unit according to the sixth aspect, one of the driving force transmitting means provided on the rotatable support shaft is the other in the axial direction. It is characterized in that it is arranged on one open side of the housing and at that position the movement in the axial direction is restricted by the restricting means and the retaining ring.

According to an eighth aspect of the present invention, a driving force transmitting unit according to one of the first to seventh aspects is used.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view of a driving force transmission unit according to an embodiment of the present invention, and FIG. 2 is a view taken in the direction indicated by reference numeral (2) in FIG. In FIG. 1, a driving force transmission unit 1 is used for a latent image carrier or a developer carrier in an image forming apparatus such as a copying machine, a printer, or a facsimile machine. The driving force transmission unit 1 shown in FIG. 1 includes a housing 1A as a main part. The housing 1A is a dish-shaped resin molded part whose one surface is open. As shown in FIG. 3, a plurality of support shafts 1B are immovably erected by integral molding inside a bottom surface facing the open surface. ing. Hereinafter, the support shaft 1B is referred to as a fixed support shaft. A gear 1C and an idle gear 1D constituting a speed reduction mechanism are respectively inserted and fixed to the fixed support shaft 1B. In FIG. 3, the housing 1A
A plurality of bosses 1E are provided on the outer surface of the bottom surface in a state protruding from the outer surface, and screw holes (not shown) are formed in the boss 1E. As shown in FIG. 2, a motor M is mounted on the boss 1E and is fastened and held.

In FIG. 2, on the bottom surface of the housing 1A,
In addition to the fixed support shaft 1B described above, an insertion support hole 1F is formed as an insertion portion capable of supporting a support shaft rotatable independently of the housing 1A (hereinafter, this support shaft is referred to as a rotation support shaft). . A bearing 2 having a flange on the outer surface of the bottom surface of the housing 1A is inserted into the insertion support hole 1F. The bearing 2 has a rotatable support shaft (hereinafter referred to as a rotation support shaft). ) 3 can be supported in a state where it can be inserted and removed.

In FIG. 2, the rotation support shaft 3 includes a compression spring 5
A rotation transmitting member provided with a joint member 6 which is biased toward a shaft end portion by a bearing, and a bearing 7 at a position opposite to the joint member 6 with the compression spring 5 interposed therebetween.
Is inserted. Of the bearings 2 and 7, the bearing 2 is a bearing that supports the rotation support shaft 3 on the housing 1A side, and the bearing 7 is a device housing to which the housing 1A is assembled as shown in FIG. The slide bearing is mounted on a shaft support MB1 of a body (indicated by a symbol MB for convenience) and supports the rotation support shaft 3 with the apparatus housing MB.
An E-shaped retaining ring 3A is fitted to the shaft end of the rotation support shaft 3 inserted and supported by the bearing 2, and restricts the rotation of the rotation support shaft 3 from moving toward the open surface side of the housing 1A. ing.

The bearing 2 for supporting the rotary shaft 3 on the housing 1A side is inserted into an insertion support hole 1F of the housing 1A. The insertion support hole 1F has a structure for preventing the bearing 2 from dropping off. Provided. FIG. 5 shows the bearing 2
It is a front view of 1 F of insertion support holes for demonstrating the fall prevention structure. In the figure, a part of the insertion support hole 1F includes:
A press-fit portion 1F1 formed of a convex portion protruding toward the center of the hole is provided. The press-fit portion 1F1 is a part integrally formed with the housing 1A, and can be compressed and deformed when the bearing 2 is inserted. For this reason, when the bearing 2 is inserted, the press-fit portion 1F1 is crushed and deformed by compression, so that the bearing 2 can be pressed against the inner peripheral surface of the insertion support hole. The bearing 2 does not fall out of the insertion support hole 1F even if the orientation is correct.

A gear 8 as a driving force transmitting means is integrated at a position adjacent to the bearing 7 in the axial direction of the rotary support shaft 3. In this embodiment, a helical gear is used as the gear 8. Have been. As shown in FIG. 4, the helical gear 8 is integrated with the rotation support shaft 3 by a holding member 9 such as a key pin that penetrates the rotation support shaft 3 in the diameter direction.

As a structure for supporting the rotation of the rotary support shaft 3, a restricting means 10 for controlling the movement of the rotary support shaft 3 in the axial direction is used in addition to the insertion support hole 1F. Details of the regulating means 10 are shown in FIGS. 2 and 3. FIG.
In FIG. 3 and FIG.
In the vicinity of the insertion support hole 1F, a driving force transmission means, which is a rib arranged opposite to one end of the helical gear 8 in the width direction. The rib serving as the restricting means 10 is a part formed as a screen-like piece (see FIGS. 1 and 5) over the inside of the side surface and the inside of the bottom surface of the housing 1A, and faces one end in the width direction of the helical gear. ing.

In this embodiment, the torsional direction of the teeth of the helical gear 8 is determined by the following conditions. In other words, the direction is a torsion direction in which the helical gear 8 generates a moving force in the direction away from the restricting means 10 when the helical gear 8 meshes. Thus, when the helical gear 8 rotates while meshing with the adjacent reduction gear, the helical gear 8 does not come into contact with the restricting means that faces the one end in the width direction. A situation in which the rotation of the gear 8 is obstructed can be avoided. The rotation of the rotary support shaft 3 in the axial direction is restricted by the retaining ring 3A mounted on the shaft end and the restricting means 10. That is, in FIG. 2, the movement of the helical gear 8 toward the open surface side of the housing 1 </ b> A
The movement to the side opposite to the open surface side is regulated by abutment between the regulating means 10 and the helical gear 8.

The housing 1A is not limited to a single support shaft that can rotate by itself, that is, a so-called rotary support shaft. That is, the plurality of rotating shafts are connected to the housing 1A.
In some cases. In this embodiment, for such a case, a configuration is provided in which one of the rotating shafts can prevent the other rotating shaft from falling off. FIG. 6 shows a housing 1A in an apparatus housing MB for explaining the above configuration.
FIG. 7 is a view showing a case where the rotary support shafts 3 and 11 are further provided in a housing 1A.

In FIG. 6, the rotation support shaft indicated by reference numeral 3 is
The rotating shaft shown by the reference numeral 11 corresponds to a portion for linking the latent image bearing member in the image forming apparatus. As shown in FIGS. 1 to 3, the rotation support shaft 11 is inserted into and supported by a bearing 12 having a flange positioned inside the bottom surface with respect to an insertion support hole 1F ′ formed on the bottom surface of the housing 1A. In this case, the bearing 12
The flange is inserted into the insertion support hole 1F 'in a state where the flange is located inside the bottom surface of the housing 1A.

The rotation support shaft 11 is provided with a joint member 14 urged toward the shaft end by a compression spring 13 at a shaft end located on the open surface side of the housing 1A.
A slide bearing 15 is mounted on the opposite side of the compression spring 13 from the joint member 14.

As shown in FIG. 6, the joint members 6 and 14 provided at the shaft ends of the rotating shafts 3 and 11 are provided on the side of the developer carrier (the member indicated by DP in FIG. 6) and the latent image. It is interlocked with the carrier side (member indicated by XR in FIG. 6). As an interlocking structure, as shown in FIG. 7B, the joint member 6 on the side of the rotation support shaft 3 has a gradient surface in the axial direction, and can be connected by joining the gradient surfaces in opposite directions. As shown in FIG. 7B, the joint member 14 on the side of the rotating shaft 11 has a shape in which a convex portion and a concave portion are adjacent to each other in a cross direction, and the facing convex portion and concave portion are fitted. It is configured to be connected by being combined. The joint member 14 on the rotation support shaft 11 side is prevented from falling off from the rotation support shaft 11 by the retaining ring 16.

A helical gear 17 forming a driving force transmitting member is mounted on the rotation support shaft 11 similarly to the rotation support shaft 3.
The helical gear 17 on the rotating shaft 11 has the following arrangement relationship with the helical gear 8 on the rotating shaft 3. FIG.
, The rotation support shaft 3 whose movement in the axial direction is restricted by the retaining ring 3A and the restricting means 10 is smaller than the helical gear 17 provided on the other rotation support shaft 11 in the open surface of the housing 1A (see FIG. 6, a helical gear 8 is located on the side indicated by reference numeral BL) (a position indicated by reference SP in FIG. 6).
In addition, they are in a relationship of being adjacent to each other. Thus, when the open surface of the housing 1A is directed downward, the helical gear 17 on the rotary support shaft 11 abuts against the helical gear 8 on the rotary support shaft 3 so that the rotary support 11 The helical gear 17 on the side is prevented from moving, so that the rotation support shaft 11 does not fall off.

Since the present embodiment has the above configuration,
As shown in FIG. 6, the housing 1A is fastened to the device housing MB and assembled. In the housing 1A, necessary gears are mounted on the fixed support shaft in advance, and the rotary support shafts 3 and 11 are inserted into the insertion support holes 1F and 1F ', and
Retained by retaining ring. One of the rotating shafts 3
Before the shaft end is inserted into the insertion support hole 1F, the members up to the bevel gear 8 including the joint member 6 are attached,
When the shaft end is inserted into the insertion support hole 1F, the helical gear 8 is adjacent to the regulating means 10. Thereby, movement of the rotation support shaft 3 in any axial direction is restricted.

In the rotary shaft 11, which has the bevel gear 17 adjacent to the rotary shaft 3, the bevel gear 17 is positioned at a position deep from the open surface of the housing 1A, and a part of the end surface is formed. Bevel gear 8 of the rotating shaft 3 located on the open surface side
Therefore, even if the housing 1A is turned to the side having the open surface before assembling to the apparatus housing MB, the housing 1A is maintained in a state where it does not fall off. Thereby, there is no assembling of the support shafts on the device housing MB side, and all the support shafts are assembled for the housing 1A, so that the support shaft assembly work can be performed collectively in the housing 1A.

When the housing 1A mounted on the apparatus housing MB is to be removed, the rotation support shaft 3 whose movement is restricted in any axial direction and a helical gear on the rotation support shaft 3 side. When the housing 1A is detached from the apparatus housing MB due to the configuration of the rotation support shaft 11 in which the movement of the housing 1A to the open surface side is restricted by the
Neither of the rotating shafts 3 and 11 remains on the device housing MB side.

According to the above-described embodiment, the rotation support shaft 3 whose movement in the axial direction is restricted is not only restricted in its own movement but also as a member for restricting the movement of another rotation support shaft. Since it is used, there is no need to provide a movement restricting member for each of the rotation shafts, thereby simplifying the configuration.

[0036]

According to the first aspect of the present invention, usually, a retaining ring used as a retaining member for a shaft and a driving force transmitting means provided on a rotatable support shaft are arranged close to each other. It is possible to restrict the rotatable support shaft from moving in any direction in the axial direction only by using the restricting means for restricting the movement of the driving force transmitting means in one axial direction. As a result, the rotatable support shaft that can be inserted into and removed from the housing is kept at the housing side, and the rotatable shaft does not drop out when the housing is attached or detached. Can be released to improve the detachability.

According to the second aspect of the present invention, since the piece integrally formed with the housing is used as the restricting means, it is possible to restrict the movement of the rotatable support shaft without requiring special assembly or the like. This is possible, and since it is integrally molded, there is no need to add new components. Thus, it is possible to prevent the components from falling off when the housing is attached and detached and to simplify the attaching and detaching process without increasing the component cost.

According to the third aspect of the present invention, the driving force transmitting means and the regulating means which are close to each other have a simple structure which only defines the twist direction of the helical teeth formed on the driving force transmitting means. This prevents contact even if they are close to each other. Thereby, the movement of the rotatable shaft itself in the axial direction can be restricted, and the operation of the driving force transmitting means can be prevented from being hindered by the restricting means.

According to the fourth and fifth aspects of the present invention, since the insertion portion on the housing side through which the rotatable support shaft is inserted is provided with the press-fit portion which can be compressed and deformed by the support of the support shaft, It is possible to prevent the bearing from falling out of the housing regardless of the insertion direction of the bearing. Accordingly, since there is no restriction that the housing is set in a direction in which the bearing does not fall off, the attaching / detaching operation becomes easy.

According to the sixth and seventh aspects of the present invention, among the respective driving force transmitting means arranged on the open surface side of the housing, the rotatable state capable of being inserted into and removed from the housing is obtained. The driving force transmission means provided on the support shaft is arranged so as not to move toward the open surface, and in particular, a support that is restricted from moving in the axial direction by using the restriction means and the retaining ring. Since the driving force transmitting means mounted on the shaft is located closer to the open surface side of the housing than the driving force transmitting means mounted on the other rotatable support shaft, the other driving force transmitting means The movement of the rotatable support shaft in the axial direction, in particular, the movement toward the open surface side is restricted. As a result, the axial movement of one rotatable support shaft can be restricted, and the axial movement of the rotatable support shaft can be restricted only by setting the positional relationship of the other rotatable support shaft with respect to this support shaft. With a simple configuration in which only one of the rotatable spindles is restricted in axial movement, it is possible to prevent the rotatable spindle that can be inserted into and removed from the housing from falling off.

According to the eighth aspect of the present invention, it is possible to obtain an apparatus capable of preventing an increase in operation cost without being restricted by an operation procedure for attaching and detaching the housing to and from the apparatus housing. .

[Brief description of the drawings]

FIG. 1 is a front view of a driving force transmission unit according to an embodiment of the present invention.

FIG. 2 is an arrow view in a direction indicated by reference numeral (2) in FIG.

FIG. 3 is a sectional view showing a housing used in the driving force transmission unit shown in FIG.

FIG. 4 is a development view of a gear group provided in the driving force transmission unit shown in FIG.

FIG. 5 is a partial arrow view in a direction indicated by reference numeral (5) in FIG. 3;

FIG. 6 is a diagram showing a state in which the driving force transmission unit shown in FIG. 1 is assembled to an apparatus housing.

FIG. 7 is a front view of a joint member provided on a rotating shaft used in the driving force transmission unit shown in FIG.

FIG. 8 is a perspective view of a housing for explaining a conventional example of a driving force transmission unit.

FIG. 9 is a rear view of the housing shown in FIG. 8;

FIG. 10 is a diagram for explaining the operation of the conventional structure shown in FIG. 8;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Driving force transmission unit 1A Housing 1B Fixed support shaft 1C, 1D Gear 1F, 1F 'Insertion support hole 1F1 Press-fit part 2, 7, 12, 15 Bearing 3,11 Rotation support shaft 3A Retaining ring 8, 17 Drive force transmission means One helical gear 10 Regulation means MB Device housing MB1 Shaft support

Claims (8)

[Claims] 1. A driving force transmission unit comprising: a housing having one surface opened and a support portion provided on a bottom surface facing the surface to support a plurality of gears for rotation; A structure in which the support shaft of the gear is formed integrally with the housing in advance, and a structure in which the support shaft is rotatably supported independently of the housing, wherein the structure for rotatably supporting the support shaft is as described above. An insertion portion formed on the bottom surface of the housing and through which the rotatable support shaft is inserted, and a restricting means provided near the insertion portion and configured to restrict movement of the rotatable support shaft in one axial direction, The restricting means is arranged in a state of being close to and facing the driving force transmitting means provided on the rotatable support shaft, and is mounted on a shaft end of the rotatable support shaft so that the support shaft is in the axial direction. Restrict movement in other directions A driving force transmission unit, wherein the rotation of the rotatable support shaft is restricted in any of the axial directions by the retaining ring and the restricting means. 2. The driving force transmitting unit according to claim 1, wherein the regulating means is formed as a single piece integrally formed on an inner surface of the housing and protruding near the driving force transmitting means. And a driving force transmission unit. 3. The driving force transmitting unit according to claim 1, wherein the driving force transmitting means provided on the rotatable support shaft is a helical gear, and the torsion direction of the teeth of the helical gear. The driving force transmission unit is set in a torsional direction that generates a moving force in a direction away from the restricting means at the time of engagement. 4. The driving force transmission unit according to claim 1, wherein the insertion portion provided in the housing has a structure for holding a bearing of the rotatable support shaft. A driving force transmission unit characterized in that: 5. The driving force transmitting unit according to claim 4, wherein the press-fit holding portion is constituted by a convex portion formed on a part of the inner surface of the insertion portion, and the convex portion is rotatable. A driving force transmission unit, which can be compressed and deformed by inserting a bearing that supports a support shaft. 6. The driving force transmitting unit according to claim 1, wherein the driving force transmitting means mounted on the rotatable support shaft is mounted on another support shaft. A driving force transmission unit, wherein the driving force transmission unit provided at least on the rotatable support shaft of the driving force transmission unit is arranged so as not to move to the open one side of the housing. . 7. The driving force transmission unit according to claim 6, wherein one of the driving force transmission means provided on the rotatable support shaft is more open than the other driving force transmission means in the axial direction. A driving force transmission unit, wherein the driving force transmission unit is disposed on one surface side, and at that position, movement in the axial direction is restricted by the restricting means and the retaining ring. 8. A driving device using the driving force transmission unit according to claim 1.