JP2019074119A - One-way clutch and image formation device - Google Patents

Abstract

Provided is a one-way clutch in which a gap between an inner ring and a shaft is reduced to prevent rattling between the two, and a shaft can be inserted from both directions. A one-way clutch (1) is an outer ring side plate (3) which is attached to an inner ring (2), an outer ring (4), and an inner ring (2) and covers one end of the outer ring (4) in the rotational axis direction. The inner ring 2 is bent so as to enter the insertion hole 20 and fitted into the inner peripheral portion of the inner ring 2. When the shaft 18 is inserted into the insertion hole 20, the shaft 18 comes into contact with the inner ring 2 and the shaft 18. An outer ring side plate 3 having an inner ring insertion portion 14 that can be elastically deformed so that the gap between the inner ring insertion portion 14 and the outer ring side plate 3 is inclined with respect to the rotation axis direction of the outer ring 4. A guide surface for guiding the shaft 18 to the insertion hole 20 is formed. [Selection] Figure 2

Description

  The present invention relates to a one-way clutch suitable for an image forming apparatus such as an electrophotographic copying machine, an electrophotographic printer, and an ink jet printer.

  Conventionally, in an image forming apparatus, rotational drive force in one direction is transmitted to a shaft for transmitting rotational drive force to a conveyance roller that conveys a sheet by rotation, and transmission of rotational drive force in the other direction is performed. A configuration is known in which a one-way clutch is mounted to shut off.

  FIG. 11 is a perspective view (FIG. 11 (a)) and a cross-sectional view (FIG. 11 (b)) of the one-way clutch 100 described in Patent Document 1. FIG. As shown in FIG. 11, the one-way clutch 100 described in Patent Document 1 is formed with an insertion hole 120 for inserting a shaft 118 and has an inner ring 102 for pivotally supporting the shaft 118. Further, it has an outer ring 104 to which a gear or the like is externally fitted. Furthermore, a plurality of needles 106 are disposed in the circumferential direction between the inner ring and the outer ring. In the one-way clutch 100, when the outer ring 104 receives a rotational drive force that rotates in one direction relative to the inner ring 102, the outer ring 104 and the inner ring 102 integrally rotate, and the rotational drive force rotates in the other direction. The outer ring 104 and the inner ring 102 rotate relative to each other. As a result, the rotational drive force in one direction is transmitted to a gear or shaft 118 (not shown), and the transmission of the rotational drive force in the other direction is shut off.

  An outer ring side plate 103 covering an end of the outer ring 104 in the rotational axis direction is attached to the inner ring 102 in the one-way clutch 100. Further, a plate spring portion 103 a bent so as to enter the insertion hole 120 of the inner ring 102 is formed on the outer ring side plate 103. In the one-way clutch 100, when the D-shaped tip of the shaft 118 is inserted in the direction of the arrow K1 with respect to the inner ring 102, the leaf spring portion 103a elastically deforms, thereby causing the inner ring 102 Absorbs the gap with the shaft 118. Thereby, rattling between the inner ring 102 and the shaft 118 is suppressed.

JP, 2015-190562, A

  FIG. 12 is a cross-sectional view of the one-way clutch 100 described in Patent Document 1 when the shaft 118 is inserted into the inner ring 102 from the arrow K2 direction opposite to the arrow K1 direction. As shown in FIG. 12, when the shaft 118 is inserted into the insertion hole 120 of the inner ring 102 in the direction of the arrow K2, the tip portion 103b of the plate spring portion 103a may interfere with the tip portion of the shaft 118. In this case, since the leaf spring portion 103a is in a cantilever shape, the leaf spring portion 103a may be deformed in the center direction of the inner ring 102 and the one-way clutch 100 may become unusable.

  Accordingly, the present invention has been made in view of such a current situation, and it is an object of the present invention to provide a one-way clutch in which a gap between an inner ring and a shaft is reduced to suppress rattling therebetween and the shaft can be inserted from both directions. With the goal.

  In order to achieve the above object, a typical configuration of a one-way clutch according to the present invention is mounted on a shaft, and transmits rotational driving force in a first direction to the shaft, and the first direction In a one-way clutch that does not transmit rotational driving force in the opposite second direction, an inner ring having a non-circular insertion hole into which the shaft is inserted and an outer peripheral portion of the inner ring are fitted to the inner ring An outer ring that rotates integrally with the inner ring when receiving a rotational driving force that rotates in a first direction, and that rotates relative to the inner ring when receiving a rotational driving force that rotates in the second direction; A flexible cover member attached to the inner ring and covering one end of the outer ring in the rotational axis direction, the cover member being bent so as to enter the insertion hole of the inner ring and being an inner periphery of the inner ring A cover member having a bending portion which can be elastically deformed such that when the shaft is inserted into the insertion hole, the shaft abuts against the shaft to reduce a gap between the inner ring and the shaft And a tip of the bent portion of the cover member is bent so as to be inclined with respect to the rotation axis direction, and a guide surface for guiding the shaft to the insertion hole is formed. I assume.

  According to the present invention, in the one-way clutch, the gap between the inner ring and the shaft can be reduced to suppress rattling therebetween, and the shaft can be configured to be insertable from both directions.

FIG. 1 is a schematic cross-sectional view of an image forming apparatus. It is a perspective view of a one way clutch. It is the front view and sectional drawing of a one way clutch. It is a disassembled perspective view of a one way clutch. It is a perspective view of an inner ring. It is a perspective view of an outer ring side plate. It is explanatory drawing for demonstrating the operation | movement which attaches an outer ring side plate to an inner ring. It is mounting | wearing explanatory drawing of the shaft of a one way clutch. It is mounting | wearing explanatory drawing of the shaft of a one way clutch. It is a figure which shows the shape of another one way clutch. It is a perspective view and sectional drawing of the conventional one-way clutch. It is sectional drawing of the conventional one way clutch.

First Embodiment
<Image forming apparatus>
Hereinafter, an entire configuration of an image forming apparatus including a one-way clutch according to a first embodiment of the present invention will be described together with an operation at the time of image formation with reference to the drawings. Note that the dimensions, materials, shapes, relative arrangements, and the like of the components described are not intended to limit the scope of the present invention to them unless otherwise specified.

  The image forming apparatus A transfers toners of four colors of yellow Y, magenta M, cyan C, and black K onto an intermediate transfer belt, and then transfers the image to a sheet to form an image. It is an apparatus. In the following description, members using the toners of the respective colors are suffixed with Y, M, C, and K, except that the configuration and operation of each member are different except for the color of the toner used. Since they are substantially the same, subscripts are appropriately omitted unless distinction is required.

  As shown in FIG. 1, the image forming apparatus A includes an image forming unit for transferring a toner image to a sheet S (recording material), a sheet feeding unit for supplying the sheet S toward the image forming unit, and A fixing unit is provided to fix the toner image.

  The sheet feeding unit feeds the sheet S fed from the pickup roller 71 and the pickup roller 71 (71a to 71d) for picking up the sheet S stacked and stored in the sheet feeding cassette 61 (61a to 61d). It has a roller 77 (77a to 77d). Further, conveyance rollers 76 (76 a to 76 d) and registration rollers 75 disposed downstream of the sheet supply roller 77 in the sheet conveyance direction are provided.

  The rotational driving force of the paper feed roller 77 and the conveyance roller 76 is transmitted from a drive source such as a motor by drive transmission means such as a belt pulley and a gear train. The pitch between the sheet feed roller 77 and the conveyance roller 76 is set to be narrower than the A4 size in the lateral direction 210 mm, and the sheet S is delivered from the sheet feed roller 77 to the conveyance roller 76 in a baton touch manner. .

  Here, a one-way clutch 1 is attached to a shaft 18 (see FIG. 7) for transmitting the rotational driving force of a driving source such as a motor to the sheet feeding roller 77. The one-way clutch 1 transmits the rotational drive force to the paper feed roller 77 via the shaft 18 when a gear (not shown) mounted on the one-way clutch 1 rotates clockwise due to the rotational drive force of the drive source. Further, when a gear (not shown) rotates counterclockwise, transmission of rotational driving force is interrupted. The configuration of the one-way clutch 1 will be described in detail later.

  Further, the rotational speed of the conveyance roller 76 is set to be faster than the rotational speed of the paper feed roller 77. As described above, when acceleration is performed by the conveyance roller 76 on the downstream side in the sheet conveyance direction, the conveyed sheet S is pulled by the conveyance speed difference between the conveyance roller 76 and the sheet feeding roller 77. Further, the surface of the transport roller 76 and the sheet feed roller 77 is covered with a material having high frictional force such as rubber, and the sheet S does not slip. Therefore, the rotational speed on the output side is faster than the rotational speed based on the rotational drive force of the drive source input to the one-way clutch 1, and the rotational drive force of the drive source is canceled. Following the conveyance speed of. Thus, the sheet conveyance speed is accelerated on the downstream side in the sheet conveyance direction, and the space between the conveyed sheets S is reduced to improve productivity.

  The image forming unit includes rotatable photosensitive drums 91 (91Y, 91M, 91C, 91K) as image bearing members, and charging rollers 92 (92Y, 92M, 92C, 92K) for charging the surface of the photosensitive drum 91. . The image forming apparatus further includes drum cleaners 95 (95Y, 95M, 95C, 95K), laser scanner units 93 (93Y, 93M, 93C, 93K), developing devices 94 (94Y, 94M, 94C, 94K), and an intermediate transfer unit 80.

  The intermediate transfer unit 80 includes a primary transfer roller 35 (35Y, 35M, 35C, 35K), an intermediate transfer belt 31, a secondary transfer roller 41, a secondary transfer opposing roller 32, a drive roller 33, a tension roller 34, a belt cleaner 99 and the like. Equipped with

  The intermediate transfer belt 31 is an endless cylindrical belt stretched around the primary transfer roller 35, the drive roller 33, the tension roller 34, and the secondary transfer counter roller 32. The intermediate transfer belt 31 rotates as the drive roller 33 receives a driving force from a motor (not shown) and is rotated by this rotation to perform a circumferential movement.

  Next, the image forming operation will be described. First, when a control unit (not shown) receives an image forming job signal, the sheet S stacked and stored in the sheet feeding cassette 61 is conveyed to the registration roller 75 by the pickup roller 71, the sheet feeding roller 77, and the conveyance roller 76. The registration roller 75 conveys the sheet S to the image forming unit after the timing of the operation of the image forming unit is matched.

  On the other hand, in the image forming portion, first, a predetermined charging bias is applied to the charging roller 92, whereby the surface of the photosensitive drum 91 is charged. Thereafter, the laser scanner unit 93 irradiates the surface of the photosensitive drum 91 with a laser beam in accordance with an image signal transmitted from an external device (not shown) or the like to form an electrostatic latent image on the surface of the photosensitive drum 91.

  Thereafter, a developing bias is applied to the developing sleeve of the developing device 94 so that the electrostatic latent image is supplied with toner and developed. Thus, toner images of the respective colors are formed on the respective photosensitive drums 91.

  The toner image formed on the photosensitive drum 91 is conveyed to the primary transfer portion formed by the photosensitive drum 91 and the primary transfer roller 35 by the rotation of the photosensitive drum 91. Thereafter, in the primary transfer portion, the primary transfer bias of the toner opposite to the regular charging polarity of the toner is applied to the primary transfer roller 35, whereby the toner images of the respective colors are primarily transferred onto the intermediate transfer belt 31.

  Thereafter, the toner image is sent to a secondary transfer portion formed by the secondary transfer roller 41 and the secondary transfer opposing roller 32 by the rotation of the intermediate transfer belt 31. Then, a secondary transfer bias is applied to the secondary transfer roller 41 at the secondary transfer portion, whereby the toner image on the intermediate transfer belt 31 is transferred onto the sheet S.

  The sheet S on which the toner image has been transferred is sent to the fixing device 83 via the conveyance belt 42, and is heated and pressed by the fixing device 83 so that the toner image is fixed to the sheet S. Thereafter, the sheet S on which the toner image is fixed is discharged onto the sheet discharge tray 65 by the discharge roller 82.

  The toner remaining on the surface of the photosensitive drum 91 after the primary transfer is scraped off by the drum cleaner 95 and removed. Similarly, toner remaining on the outer peripheral surface of the intermediate transfer belt 31 after the secondary transfer is scraped off by the belt cleaner 99 and removed.

<One-way clutch>
Next, the configuration of the one-way clutch 1 will be described.

  FIG. 2 is a perspective view of the one-way clutch 1. FIG. 3 is a front view of the one-way clutch 1 (FIG. 3 (a)) and a cross-sectional view taken along a line A1-A1 (FIG. 3 (b)). FIG. 4 is an exploded perspective view of the one-way clutch 1. The one-way clutch 1 according to the present embodiment is generally called a roller type or a needle type.

  As shown in FIGS. 2 to 4, the one-way clutch 1 is composed of an inner ring 2, an outer ring 4 and an outer ring side plate 3. The one-way clutch 1 is mounted on a shaft 18 (see FIG. 8). The shaft 18 has a flat surface 19 in which a part of the surface is flatly cut in the radial direction, whereby the cross-sectional shape of one end in the thrust direction is shaped to be D-shaped.

  The outer ring 4 is formed of a sintered material made of a metal powder material. The material of the outer ring 4 contains inclusions that increase the slidability, and the porous space of the porous structure is impregnated with a lubricant to enhance the lubricity.

  A plurality of anti-rotation grooves 5 are formed on the outer peripheral surface of the outer ring 4. The anti-rotation groove 5 is engaged with a convex portion of a gear (not shown) externally fitted to the outer ring 4 to prevent relative rotation between the outer ring 4 and the gear. The arrow-shaped inscription 25 formed on the outer ring 4 clearly indicates that the one-way clutch 1 transmits the rotational driving force only in one direction.

  Further, in the outer ring 4, six pocket portions 4 p having a wedge surface 4 s which is a wedge-shaped slope are formed circumferentially equally. The wedge surface 4 s forms a surface such that the radial width is narrowed from one side to the other side in the rotation direction of the outer ring 4.

  Further, in the pocket portion 4p, a needle 6 as a rotatable body and a spring (not shown) such as a compression spring, a plate spring, and a resin spring are disposed. The needle 6 is biased by a spring (not shown) in the direction in which the radial width of the pocket 4p is narrowed. As a result, the needle 6 is held by the pocket 4 p in a state of being engaged with the wedge surface 4 s and in contact with the outer peripheral portion of the inner ring 2.

  An insertion hole 20 for inserting the shaft 18 is formed in the center of the inner ring 2. The insertion hole 20 is a non-circular hole having a D-shaped cross section. Further, the inner ring 2 has two flat surfaces 10 (flat portions) in which a part of the inner peripheral portion is formed flat. By mounting the flat surface 10 of the inner ring 2 and the flat surface 19 of the shaft 18 opposite to each other, the rotation of the shaft 18 with respect to the inner ring 2 is suppressed.

  The outer ring side plate 3 (cover member) is attached to the inner ring 2 and covers one end of the outer ring 4 in the rotational axis direction. Further, the outer ring side plate 3 prevents the needle 6 from coming off and regulates the relative movement of the outer ring 4 and the inner ring 2 in the rotational axis direction.

  The outer ring side plate 3 is formed of a flexible metal plate formed by pressing a flat spring material such as a thin plate stainless steel plate for spring (SUS304CSP), a phosphor bronze plate for spring, a beryllium plate for spring, etc. It is a body. The outer ring side plate 3 has a spring property enhanced by heat treatment.

  With regard to the assembly of the one-way clutch 1, first, the inner ring 2 is inserted into the outer ring 4 until the flange portion 7 formed on the inner ring 2 abuts on the outer ring 4. As a result, the inner ring 2 is mounted on the outer ring 4 in a state in which the slippage in the thrust direction is prevented. Next, the outer ring side plate 3 is attached to the inner ring 2. Thus, the one-way clutch 1 is assembled.

  Next, the drive transmission operation of the one-way clutch 1 will be described.

  First, the outer ring 4 rotates in the clockwise direction (first direction) relative to the inner ring 2 by the clockwise rotation of a gear (not shown) externally fitted to the outer ring 4 or the counterclockwise rotation of the shaft 18 In this case, the needle 6 bites into and engages the wedge surface 4s and loses a relief. As a result, the contact surface pressure between the wedge surface 4s of the outer ring 4 and the needle 6 becomes high, and the outer ring 4 and the inner ring 2 are brought into an engaged state in which they rotate integrally. That is, when the outer ring 4 receives a rotational driving force that rotates in a clockwise direction relative to the inner ring 2, the outer ring 4 and the inner ring 2 integrally rotate to transmit the rotational driving force between the two. .

  On the other hand, when the outer ring 4 rotates in the counterclockwise direction (the second direction) relative to the inner ring 2 due to the counterclockwise rotation of the gear or the clockwise rotation of the shaft 18, the needle 6 The pocket portion 4p is moved by a minute distance in a direction in which the radial width is wide against the biasing force. As a result, the needle 6 is released from the state of biting into the wedge surface 4s, and the contact surface pressure between the wedge surface 4s and the needle 6 becomes low. As a result, the needle 6 slips with respect to the inner ring 2, and the outer ring 4 and the inner ring 2 rotate relative to each other (the outer ring 4 or the inner ring 2 slips), which is a non-engagement state. That is, when the outer ring 4 receives a rotational driving force that rotates in a counterclockwise direction relative to the inner ring 2, the outer ring 4 and the inner ring 2 relatively rotate, and the transmission of the rotational driving force is blocked between them. Be done.

<Inner ring>
FIG. 5 is a perspective view of the inner ring 2. As shown in FIG. 5, the retaining groove portion 11 and the side plate receiving portion 13 are on the outer peripheral portion 8 of the inner ring 2 at the end opposite to the side where the flange portion 7 is formed in the rotational axis direction Is formed. Further, a guide portion 12 is formed at an end portion of the inner peripheral portion 9 of the inner ring 2 opposite to the side where the flange portion 7 is formed in the rotational axis direction of the inner ring 2.

  Further, between the two flat surfaces 10 formed in the inner peripheral portion 9 of the inner ring 2, a passage groove 10a cut out in the direction (the outer peripheral portion side) in which the thickness becomes smaller penetrates in the rotational axis direction. Is formed. Further, on the outer side of the two flat surfaces 10 in the rotational direction of the inner ring 2, two fitting grooves 10b cut out in the direction of decreasing the thickness are formed to penetrate in the rotational axis direction. The fitting groove 10b is inclined with respect to the direction (direction of line G shown in FIG. 5 (b)) orthogonal to the rotation axis direction (direction of line H shown in FIG. 5 (b)) of the inner ring 2 (outer ring 4) Inclined grooves. The rotation axis of the inner ring 2 (outer ring 4) is an imaginary line connecting the rotation centers of the inner ring 2 (outer ring 4).

  In the inner ring 2, the inner circumferential portion 9 for axially supporting the shaft 18 is finished to a diameter defined by an intermediate offset dimension of the fitting tolerance and is formed concentric with the outer circumferential portion 8. Further, the inner ring 2 is set to an intermediate offset of the fitting tolerance so as to be fitted to the outer ring 4.

<Outer ring side plate>
FIG. 6 is a perspective view of the outer ring side plate 3. As shown in FIG. 6, the outer ring side plate 3 includes an annular side plate portion 3a, four locking claws 17 (engaging portions) obtained by bending the inner peripheral portion of the side plate portion 3a diagonally, and the side plate portion 3a. It has the inner ring insertion part 14 which bent the circumference part in the opposite side to the locking claw 17.

  At both end portions of the inner ring insertion portion 14, a plate spring portion 14a (abutment portion) bent obliquely is formed. Further, on both end portions of the inner ring insertion portion 14 and on the tip end side with respect to the plate spring portion 14a, a bent fitting portion 14b bent at an angle fitted to the fitting groove 10b (recessed portion) of the inner ring 2 is formed. It is done. Further, at the tip of the inner ring insertion portion 14, a bending guide portion 14c which is bent obliquely is formed.

  FIG. 7 is an explanatory view for explaining an operation of attaching the outer ring side plate 3 to the inner ring 2. As shown in FIG. 7A, when the outer ring side plate 3 is attached to the inner ring 2, first, the bending fitting portion 14b and the bending guide are guided while the inner ring insertion portion 14 is guided by the guide portion 12 formed on the inner ring 2. The portion 14c is inserted into the passage groove 10a and the fitting groove 10b of the inner ring 2, respectively.

  Next, the positioning portion 16 of the outer ring side plate 3 is abutted against the positioning receiving portion 13 of the inner ring 2 to determine the position of the outer ring side plate 3 with respect to the inner ring 2. Thereafter, as shown in FIG. 7C, the locking claws 17 of the outer ring side plate 3 are locked in a snap fit manner to the retaining grooves 11 of the inner ring 2. Thereby, the outer ring side plate 3 is fixed to the inner ring 2 and attached.

  In the state where the outer ring side plate 3 is attached to the inner ring 2, the tip end portion of the inner ring insertion portion 14 is disposed inside the end portion in the rotation axis direction of the inner ring 2 (the outer ring 4). The bending fitting portion 14b is loosely fitted to the fitting groove 10b.

  That is, the inner ring insertion portion 14 of the outer ring side plate 3 is bent so as to enter the insertion hole 20 formed in the inner ring 2, and the fitting groove 10b formed in the inner circumferential portion 9 of the inner ring 2 in the bending fitting portion 14b. And a bent portion that mates with the The bending fitting portion 14b is a fitting portion that fits with the fitting groove 10b. Further, as shown in FIG. 3 (b), the bending guide portion 14c of the inner ring insertion portion 14 is inclined relative to the rotation axis direction (the direction of the line H shown in FIG. 3 (b)) of the inner ring 2 (outer ring 4). It is bent like so.

<Mounting on the shaft>
Next, mounting of the one-way clutch 1 on the shaft 18 will be described.

  8 and 9 are explanatory views of the one-way clutch 1 mounted on the shaft 18. 8 (a) is a perspective view of the one-way clutch 1 before the shaft 18 is mounted, and FIG. 8 (b) is a perspective view of the one-way clutch 1 when the shaft 18 is mounted. 9 (a) is a front view of the one-way clutch 1 when the shaft 18 is attached, and FIG. 9 (b) is a cross-sectional view when attached in the A2-A2 cross section.

  As shown in FIGS. 8 and 9, when the one-way clutch 1 is mounted on the shaft 18, the flat surface 10 of the inner ring 2 and the flat surface 19 of the shaft 18 are formed in the inner ring 2 of the one-way clutch 1 The shaft 18 is inserted into the insertion hole 20 from the direction of the arrow K3.

  Here, when the shaft 18 is inserted into the insertion hole 20 of the inner ring 2, the flat surface 19 of the shaft 18 abuts on the plate spring portion 14a in the insertion process, and the tip of the plate spring portion 14a is bent. Thereby, the leaf spring portion 14a is stretched by repulsive elasticity between the flat surface 10 of the inner ring 2 and the flat surface 19 of the shaft 18 to absorb a gap between the shaft 18 and the inner ring 2 caused by dimensional tolerance or the like.

  That is, when the shaft 18 is inserted into the insertion hole 20, the inner ring insertion portion 14 of the outer ring side plate 3 abuts against the shaft spring portion 14a of the inner ring insertion portion 14 and the shaft 18 It is configured to be elastically deformable so as to reduce the gap between them. By making the gap between the two smaller by elastic deformation of the inner ring insertion portion 14 in this manner, rattling during rotational drive between the two is suppressed, and transmission of drive can be performed more accurately.

  In addition, since a frictional force is generated as the shaft 18 is inserted, it can be confirmed that there is no backlash between the shaft 18 and the inner ring 2 depending on whether or not the frictional force is satisfied. For this reason, it is possible to prevent in advance mixing of the one-way clutch 1 in which the shaft 18 and the inner ring 2 rattle.

  Further, in the configuration of the present embodiment, it is also possible to insert the shaft 18 into the insertion hole 20 formed in the inner ring 2 from the arrow K4 direction opposite to the arrow K3 direction shown in FIG. That is, the bending guide portion 14 c at the tip of the inner ring insertion portion 14 is bent so as to be inclined with respect to the rotation axis direction of the inner ring 2 (the outer ring 4), and serves as a guide surface for guiding the shaft 18 into the insertion hole 20 . Therefore, when the end of the shaft 18 abuts on the bending guide portion 14c, the shaft 18 moves along the inclined surface of the bending guide portion 14c and is guided to the insertion hole 20 of the inner ring 2 without interference. .

  Further, the bending fitting portion 14b of the inner ring insertion portion 14 is fitted in a fitting groove 10b which is inclined with respect to the direction orthogonal to the rotation axis direction of the inner ring 2 (the outer ring 4). For this reason, even if a strong load is applied to the bending guide portion 14c due to the abutment of the tip of the shaft 18, if the inner ring insertion portion 14 tries to deform, the bending fitting portion 14b interferes with the fitting groove 10b Is regulated. Therefore, even when the shaft 18 is inserted from the direction opposite to the direction of the arrow K4, the inner ring insertion portion 14 maintains a predetermined size, and the shaft 18 and the inner ring 2 are fixed without rattling.

  As described above, according to the one-way clutch 1 according to the present embodiment, rattling with the shaft 18 can be suppressed, and the shaft 18 can be inserted from both directions. Therefore, the drive can be accurately transmitted to the shaft 18, and the degree of freedom in the arrangement of the one-way clutch 1 can be improved.

  Further, in the one-way clutch 1 of the present embodiment, in order to dispose the tip of the inner ring insertion portion 14 of the outer ring side plate 3 inside the end of the inner ring 2 in the rotational axis direction, the locking claw 17 is the inner ring 2 (the outer ring 4). It can form in multiple numbers at equal intervals in the rotation direction of. That is, as shown in FIG. 10A, even if the inner ring insertion portion 14 is extended to the flange portion 7 of the inner ring 2 and the tip of the inner ring insertion portion 14 is bent along the flange portion 7 of the inner ring 2, the inner ring insertion portion Interference between the tip 14 and the shaft 18 can be avoided. However, in this configuration, the expanded shape in which the bent portion of the outer ring side plate 3 is extended in a planar shape becomes the shape shown in FIG. 10B, and the locking claws 17 can not be formed at equal intervals in the rotation direction of the inner ring 2. On the other hand, according to the present embodiment, in order to dispose the tip of the inner ring insertion portion 14 of the outer ring side plate 3 inside the end of the inner ring 2 in the rotational axis direction, the locking claw 17 is rotated by the inner ring 2 (the outer ring 4). A plurality of members can be arranged at equal intervals in the direction, and the mounting strength with the inner ring 2 can be improved.

  In the present embodiment, the image forming apparatus A is described as an example of the article on which the one-way clutch 1 is mounted, but the present invention is not limited to this, and the same effects can be obtained even when used for other articles. Can.

1 ... one-way clutch 2 ... inner ring 3 ... outer ring side plate (cover member)
4 outer ring 7 flange portion 10b fitting groove (recessed portion, inclined groove)
14 Inner ring insertion part (bent part)
14a ... leaf spring portion (contact portion)
14b: Bending fitting part (fitting part)
14c ... bending guide portion (guide surface)
17: Locking claw (engaging portion)
20: Insertion hole 77: Paper feed roller (conveying roller)
18: Shaft A: image forming apparatus

Claims (11)

A one-way clutch mounted on a shaft and transmitting rotational driving force in a first direction to the shaft and not transmitting rotational driving force in a second direction opposite to the first direction,
An inner ring having a non-circular insertion hole into which the shaft is inserted, the shaft supporting the shaft;
A rotation that rotates integrally with the inner ring and rotates in the second direction when fitted with the outer peripheral portion of the inner ring and receives a rotational driving force that rotates in the first direction with respect to the inner ring An outer ring that rotates relative to the inner ring when receiving a driving force,
A flexible cover member attached to the inner ring and covering one end of the outer ring in the rotational axis direction, the cover member being bent to enter the insertion hole of the inner ring and being an inner circumferential portion of the inner ring A cover member having a bending portion which can be elastically deformed such that when the shaft is inserted into the insertion hole, the shaft abuts against the shaft to reduce a gap between the inner ring and the shaft ,
Equipped with
A tip of the bent portion of the cover member is bent so as to be inclined with respect to the rotation axis direction, and a guide surface for guiding the shaft to the insertion hole is formed. .   2. The one-way clutch according to claim 1, wherein a tip end portion of the bent portion is disposed inward from an end portion in the rotation axis direction of the inner ring.   The one-way clutch according to claim 1 or 2, wherein a side end of the bent portion is bent to be in contact with the shaft to form an elastically deformable contact portion. A recess is formed in the inner circumferential portion of the inner ring,
The fitting part bent so that it may be fitted in the said recessed part is formed in the side edge part of the said bending part, and the position different from the said contact part is characterized by the above-mentioned. One-way clutch.   The one-way clutch according to claim 4, wherein the recess is an inclined groove which is inclined with respect to a direction orthogonal to the rotation axis direction.   The one-way clutch according to any one of claims 1 to 5, wherein the cover member further includes an engaging portion that engages with the outer peripheral portion of the inner ring.   The one-way clutch according to claim 6, wherein a plurality of engaging portions are formed at equal intervals in a rotational direction of the outer ring. The inner ring includes a flat portion in which a part of the inner circumferential portion is formed flat,
The one-way clutch according to any one of claims 1 to 7, wherein the bent portion is disposed at a position facing the flat portion.   A flange for determining the position of the outer ring with respect to the inner ring is formed at the end of the inner ring in the direction of the rotation axis and opposite to the side where the cover member is attached. The one-way clutch according to any one of claims 1 to 8, characterized in that   The one-way clutch according to any one of claims 1 to 9, wherein the cover member is formed of a metal plate. An image forming unit that forms an image on a recording material;
A conveyance roller that rotates to convey the recording material;
Equipped with
An image forming apparatus, wherein the one-way clutch according to any one of claims 1 to 10 is mounted on a shaft for transmitting a drive to the transport roller.

Images