JP2018062965A - One-way clutch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a coil spring to expand or contract in a state where a posture of the coil spring is stabilized without forming a through hole at an outer ring in a one-way clutch.SOLUTION: This one-way clutch includes: an outer ring 3; a roller 4; a coil spring 5; a spring cap 6; and a spring seat 7. The outer ring 3 has a pocket part 10 which is provided so as to be recessed toward the radial outer side and disposed at the radial outer side of a shaft member 2. The roller 4 is stored in the pocket part 10. The coil spring 5 is stored in the pocket part 10 and biases the roller 4 in a circumferential direction. The spring cap 6 is disposed between the coil spring 5 and the roller 4 and supports at least a part of an outer periphery of the coil spring 5. The spring seat 7 is disposed between the coil spring 5 and a wall surface of the pocket part 10 and supports at least a part of an inner periphery of the coil spring 5.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a one-way clutch.

  The one-way clutch is generally provided on the radially outer side of the shaft member. This one-way clutch mainly includes an outer ring, a plurality of rollers, and a plurality of coil springs. The outer ring is disposed on the radially outer side of the shaft member and has a plurality of pocket portions. The roller and the coil spring are accommodated in the pocket portion, and the roller is biased in one direction of rotation by the spring. The one-way clutch includes a cover and a plate arranged so as to cover both sides of the pocket portion in the axial direction.

  In the conventional one-way clutch, a through hole may be formed so as to face the pocket portion from the outer periphery of the outer ring (see, for example, FIG. 4 of Patent Document 1). In such a type of one-way clutch, a cylindrical spring cap is put on the front end of the coil spring, and the spring cap and the coil spring are inserted into the through hole so that the front end contacts the roller. In this case, the coil spring is prevented from falling.

  On the other hand, there is also provided a one-way clutch in which a roller is pushed by using an accordion spring without using a coil spring without forming a through hole in the outer ring (Patent Document 2).

JP 2003-214461 A JP 2010-138923 A

  In the one-way clutch of Patent Document 1, since the accordion spring is used, the problem of the spring falling does not occur. Therefore, the through hole of the outer ring can be eliminated. However, the accordion spring is expensive and hinders cost reduction.

  An object of the present invention is to enable a one-way clutch to be expanded and contracted in a state in which a posture of a coil spring is stabilized without forming a through hole in an outer ring.

  (1) The one-way clutch according to the present invention is provided on a shaft member. The one-way clutch includes an outer ring, a roller, a coil spring, a spring cap, and a seat member. An outer ring | wheel has a pocket part provided so that it might become depressed toward the radial direction outer side, and is arrange | positioned at the radial direction outer side of a shaft member. The roller is stored in the pocket portion. The coil spring is housed in the pocket portion and biases the roller in the circumferential direction. The spring cap is disposed between the coil spring and the roller, and supports at least a part of the outer periphery of the coil spring. The seat member is disposed between the coil spring and the wall surface of the pocket portion, and supports at least a part of the inner periphery of the coil spring.

  Here, the outer periphery is supported by a spring cap on one side of the coil spring, and the inner periphery is supported by a sheet member on the other side. For this reason, the fall at the time of expansion / contraction of a coil spring can be suppressed, without inserting a coil spring in a through-hole.

  (2) Preferably, a guide member for guiding the circumferential movement of the spring cap is further provided.

  In this case, when the coil spring expands and contracts, the spring cap moves in the same manner, but the movement of the spring cap is guided by the guide member. For this reason, the fall of the coil spring can be further suppressed.

  (3) Preferably, it further includes a cover and a plate arranged so as to sandwich the outer ring and the roller in the axial direction. The guide member is provided on at least one of the cover and the plate so as to support the inner peripheral side of the spring cap.

  Here, a guide member is provided on the cover and / or the plate, and the inner peripheral side of the spring cap is supported by the guide member. For this reason, the coil spring is reliably prevented from falling, and the spring cap moves smoothly.

  (4) Preferably, the guide member is formed by bending a part of the cover and / or the plate. In this case, the guide member can be realized with a simple configuration.

  (5) Preferably, the spring cap has a spring contact portion and a side wall portion. The spring contact portion contacts the roller-side end surface of the coil spring. The side wall portion extends from the spring abutting portion to the coil spring side and demarcates an accommodation space for accommodating an end portion of the coil spring on the roller side. The side wall portion has a first slit and a second slit. The first slit communicates the housing space and the outside on the radially outer side and extends along the length direction of the coil spring. The second slit communicates the housing space and the outside on the radially inner side and extends along the length direction of the coil spring.

  In order to insert the end portion of the coil spring into the spring cap, the diameter of the coil spring needs to be sized so as to fit in the spring cap. For this reason, the outer diameter of the coil spring is relatively small.

  However, in the present invention, the side wall portion of the spring cap has the first slit and the second slit. For this reason, the diameter of the coil spring arrange | positioned in the accommodation space of a side wall part can be enlarged by the part of each slit. Thus, since the diameter of the coil spring can be increased as compared with the conventional one, the coil spring can be expanded and contracted in a stable posture.

  (6) Preferably, the side wall portion of the spring cap is set longer than the contact length of the coil spring. The spring cap has a tapered surface whose diameter increases toward the outside at the opening.

  Here, when the spring cap collides with the spring seat due to impact or the like, if the spring cap collides with the center of the spring seat being coincident, the coil spring is compressed straight, so that the coil spring is not damaged. .

  However, if the spring cap and the spring seat are misaligned and the two collide, a part of the coil spring is sandwiched between the opening end of the spring cap and the spring seat (for example, a protruding portion), and the coil spring is plastically deformed. There is a case.

  Therefore, here, a tapered surface is formed in the opening of the spring cap. For this reason, when a spring cap collides with a spring seat by impact etc., it is prevented that a coil spring is damaged.

  (7) Preferably, the sheet member has a support part and a projection part. The support portion contacts the wall surface of the pocket portion and supports the end surface of the coil spring. The protrusion extends from the contact portion into the coil spring and supports the inner peripheral portion of the coil spring.

  In the present invention as described above, in the one-way clutch, the coil spring can be expanded and contracted in a state where the posture of the coil spring is stabilized without forming a through hole in the outer ring.

1 is a front view of a one-way clutch according to an embodiment of the present invention. The longitudinal cross-sectional view of FIG. The pocket part enlarged view of FIG. The figure which shows the state which the roller moved from the position of FIG. VV sectional view taken on the line of FIG. VI-VI sectional view taken on the line of FIG.

  1 and 2 show a one-way clutch 1 according to an embodiment of the present invention. In the following description, the axial direction refers to the direction in which the rotating shaft of the one-way clutch 1 extends. The radial direction refers to the radial direction of a circle centered on the rotation axis of the one-way clutch 1. The circumferential direction refers to the circumferential direction of a circle around the rotation axis of the one-way clutch 1.

[overall structure]
The one-way clutch 1 is used for a driving system or a starting system of a motorcycle or the like, and is attached to the outside of the shaft member 2 in the radial direction. The one-way clutch 1 includes an outer ring 3, a plurality of rollers 4, a plurality of coil springs 5, a plurality of spring caps 6, and a plurality of spring seats 7. The one-way clutch 1 includes a plate 8 and a cover 9.

[Outer ring 3]
The outer ring 3 is an annular member to which torque is transmitted from the shaft member 2. The outer ring 3 is disposed on the radially outer side of the shaft member 2. The outer ring 3 has a plurality of pocket portions 10 in the inner peripheral portion. The outer ring 3 has a plurality of holes 12. The holes 12 are arranged at equal intervals in the circumferential direction. The hole 12 is for allowing a bolt to pass therethrough in order to attach the one-way clutch 1 to another member of the drive system. The pocket portion 10 is formed between two adjacent holes 12.

  The plurality of pocket portions 10 have the same shape. The pocket portion 10 is provided at the inner peripheral end portion of the outer ring 3 so as to be recessed outward in the radial direction. As shown in FIG. 3, each pocket portion 10 includes a first side wall portion 15, a second side wall portion 16, a first peripheral wall portion 17, and a second peripheral wall portion 18.

  The 1st side wall part 15 and the 2nd side wall part 16 are arrange | positioned so that it may oppose in the circumferential direction. The first peripheral wall portion 17 and the second peripheral wall portion 18 connect the first side wall portion 15 and the second side wall portion 16 at the bottom of the pocket portion 10.

  The first side wall 15 and the first peripheral wall 17 form a space in which the roller 4 is accommodated. This space has a narrower radial gap as it approaches the first side wall 15 from the side away from the first side wall 15. The second peripheral wall portion 18 has a smaller inner diameter than the first peripheral wall portion 17. A space in which the coil spring 5, the spring cap 6, and the spring seat 7 are accommodated is formed by the second peripheral wall portion 18 and the second side wall portion 16.

  As is clear from FIG. 2, the outer ring 3 has a larger diameter on the cover 9 side than the plate 8 side, and a stepped portion is formed.

[Roller 4]
As shown in FIG. 3, the roller 4 is a member for transmitting the power from the shaft member 2 to the outer ring 3. The roller 4 is formed in a columnar shape extending along the rotation axis of the shaft member 2 and is accommodated in the pocket portion 10.

[Coil spring 5]
The coil spring 5 is disposed inside the pocket portion 10 and biases the roller 4 in the circumferential direction. Specifically, the coil spring 5 urges the roller 4 in the circumferential direction via the spring cap 6. The coil spring 5 is set by being compressed between the roller 4 and the spring seat 7. For this reason, the roller 4 is always urged toward the first side wall 15 by the coil spring 5.

  The coil spring 5 has a circular cross section. One end of the coil spring 5 contacts the spring cap 6 and the other end contacts the spring seat 7.

[Spring cap 6]
The spring cap 6 is disposed between the coil spring 5 and the roller 4 and supports a part of the outer periphery of the coil spring 5. The spring cap 6 is made of resin and includes a spring contact portion 61 and a side wall portion 62 as shown in FIGS. 4 to 6. The spring contact portion 61 has a rectangular shape, the outer surface contacts the roller 4, and the end surface of the coil spring 5 contacts the inner surface.

  The side wall part 62 is cylindrical and extends from the spring contact part 61 to the coil spring 5 side. The side wall 62 is set to be longer than the contact length of the coil spring 5, and defines a storage space 63 for storing the end of the coil spring 5 on the roller side. The accommodation space 63 has a circular cross section and is larger than the outer diameter of the coil spring 5, but has an inner diameter that is substantially the same as the outer diameter of the coil spring 5. That is, the side wall 62 supports the outer periphery of the coil spring 5.

  The side wall 62 has a first slit 62a and a second slit 62b that are formed to face each other. The first slit 62 a communicates the housing space 63 and the outside on the radially outer side, and extends along the length direction of the coil spring 5. The second slit 62 b communicates the accommodation space 63 and the outside on the radially inner side and extends along the length direction of the coil spring 5. The outer surface of the coil spring 5 enters these slits 62a and 62b.

  In addition, a tapered surface 62c whose diameter increases toward the spring seat 7 is formed in the opening of the side wall 62. More specifically, the tapered surface 62 c is formed on a part of the inner peripheral surface of the side wall portion 62. The tapered surface 62c is formed so that the outer diameter gradually increases from the substantially central portion in the longitudinal direction of the side wall portion 62 toward the spring seat 7 side.

[Spring seat 7]
The spring seat 7 is disposed between the coil spring 5 and the second side wall portion 16. As shown in FIG. 5 and the like, the spring seat 7 has a support portion 71 and a protrusion 72.

  The support portion 71 is formed in a substantially rectangular shape, and has a first support surface 71 a that abuts on the second side wall portion 16 and a second support surface 71 b that abuts the end surface of the coil spring 5. The first support surface 71 a is formed along the shape of the second side wall portion 16. The second support surface 71b is planar.

  The protrusion 72 is formed at the center of the support 71, extends toward the roller 4, and is inserted into the coil spring 5. The outer diameter of the protrusion 72 is smaller than the inner diameter of the coil spring 5, but is substantially the same as the inner diameter of the coil spring 5. That is, the protrusion 72 supports the coil spring 5 from the inside.

[Plate 8 and cover 9]
The plate 8 covers the side surface on one side of the outer ring 3 in the axial direction. The cover 9 covers the other side surface of the outer ring 3 in the axial direction. The pocket portion 10 is covered with the plate 8 and the cover 9. That is, the plate 8 and the cover 9 prevent the roller 4 and the coil spring 5 in the pocket portion 10 from dropping from the pocket portion 10.

  As shown in FIG.1 and FIG.2, the plate 8 is a disk-shaped member, and has the hole 8a in the center part. The shaft member 2 passes through the hole 8a. The plate 8 is fixed to the outer ring 3 by bolts (not shown).

  The cover 9 is a disk-shaped member and has a hole 9a at the center. The shaft member 2 passes through the hole 9a. The cover 9 has a cylindrical portion 9b at the outer peripheral end portion. The cylindrical portion 9 b covers the outer peripheral large diameter portion of the outer ring 3. For example, the cylindrical portion 9b is formed by bending the outer peripheral end portion of the cover 9 in the axial direction. The tip of the cylindrical portion 9 b is caulked to the step portion of the outer ring 3. With such a structure, the cover 9 is fixed to the outer ring 3.

  The cover 9 is formed with a plurality of guides 9c. The guide 9 c is formed so as to enter the pocket portion 10 from the inner peripheral end of the cover 9. The guide 9c is formed by bending a part of the inner periphery of the cover 9 to the plate 8 side. As is clear from FIG. 3 and the like, the guide 9c has a length that covers almost the entire length of the side wall portion 62 of the spring cap 6. And the guide 9c supports the inner peripheral side of the side wall part 62, and guides that the spring cap 6 moves to the circumferential direction. As shown in FIG. 4, even if the roller 4 has moved to a position where it abuts against the side wall 15 (this state does not occur in normal operation), the guide 9 c abuts against the spring cap 6. It is set to such a length.

[Operation]
When the shaft member 2 rotates relative to the outer ring 3 in the direction R shown in FIG. 1, the rotation of the shaft member 2 causes the roller 4 to move toward the first side wall portion 15 side of the pocket portion 10 and By engaging with the first peripheral wall portion 17, the torque of the shaft member 2 is transmitted to the outer ring 3 via the roller 4.

  On the contrary, when the shaft member 2 rotates relative to the outer ring 3 in the direction opposite to R, the roller 4 resists the urging force of the coil spring 5 by the rotation of the shaft member 2, and the second side wall of the pocket portion 10. Move to the part 16 side. For this reason, the engagement of the roller 4 with the shaft member 2 and the outer ring 3 is released, and the roller 4 enters a free state between the shaft member 2 and the outer ring 3. As a result, the shaft member 2 idles and torque is not transmitted from the shaft member 2 to the outer ring 3.

  During the operation as described above, the coil spring 5 expands and contracts. At this time, the outer periphery of the coil spring 5 is supported by the side wall 62 of the spring cap 6, and the inner periphery is supported by the protrusion 72 of the spring seat 7. The spring cap 6 is guided to move in the circumferential direction by a guide 9c. Therefore, the coil spring 5 expands and contracts straight along its central axis without being deformed to the outer peripheral side or the inner peripheral side.

  In addition, when the spring cap 6 collides with the spring seat 7 due to an impact or the like, there is a case in which the spring cap 6 and the spring seat 7 collide with their centers being shifted by a gap existing around the spring cap 6.

  Even in such a case, since the tapered surface 62 c is formed in the opening of the spring cap 6, a part of the coil spring 5 is sandwiched between the opening end of the spring cap 6 and the protrusion 72 of the spring seat 7. Thus, the plastic deformation of the coil spring 5 can be avoided.

[Other Embodiments]
The present invention is not limited to the above-described embodiments, and various changes or modifications can be made without departing from the scope of the present invention.

  (A) The number of pocket portions, rollers, and coil springs is not limited to the above embodiment.

  (B) The guide 9c may be formed on the plate side. Moreover, you may form in both a cover and a plate.

  (C) In the above embodiment, the spring cap is formed of resin, but the plate member may be formed by sheet metal processing.

  (D) Although the plate 8 is provided in the embodiment, the plate 8 may be omitted.

DESCRIPTION OF SYMBOLS 1 One-way clutch 2 Shaft member 3 Outer ring 4 Roller 5 Coil spring 6 Spring cap 61 Spring contact part 62 Side wall part 62a 1st slit 62b 2nd slit 62c Tapered surface 63 Accommodating space 7 Spring sheet 71 Support part 72 Projection part 10 Pocket Part

Claims (7)

An outer ring disposed on a radially outer side of the shaft member, the one-way clutch provided on the shaft member, having a plurality of pocket portions provided so as to be recessed toward a radially outer side;
A roller housed in the pocket portion;
A coil spring housed in the pocket portion and biasing the roller in the circumferential direction;
A spring cap disposed between the coil spring and the roller and supporting at least a part of an outer periphery of the coil spring;
A sheet member disposed between the coil spring and the wall surface of the pocket portion and supporting at least a part of the inner periphery of the coil spring;
One-way clutch with   The one-way clutch according to claim 1, further comprising a guide member that guides the circumferential movement of the spring cap. A cover and a plate arranged to sandwich the outer ring and the roller in the axial direction;
The guide member is provided on at least one of the cover and the plate so as to support the inner peripheral side of the spring cap.
The one-way clutch according to claim 2.   The one-way clutch according to claim 3, wherein the guide member is formed by bending a part of the cover and / or the plate. The spring cap includes a spring contact portion with which an end surface of the coil spring on the roller side contacts, and a housing that extends from the spring contact portion to the coil spring side and houses an end portion of the coil spring on the roller side. A side wall that defines a space, and
The side wall portion is
A first slit that communicates between the housing space and the outside at a radially outer side, and extends along a length direction of the coil spring;
A second slit that communicates the housing space and the outside on the radially inner side and extends along a length direction of the coil spring;
Having
The one-way clutch according to any one of claims 1 to 4. The side wall portion of the spring cap is set longer than the contact length of the coil spring,
The spring cap has a tapered surface whose diameter increases toward the outside at the opening,
The one-way clutch according to claim 5. The sheet member is
Abutting against the wall surface of the pocket portion and supporting the end surface of the coil spring;
A protrusion that extends from the support into the coil spring and supports an inner periphery of the coil spring;
Having
The one-way clutch according to any one of claims 1 to 6.

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