Cam clutch unit

Abstract

A cam clutch unit includes a plurality of cams and a plurality of rollers disposed so as to be aligned in a circumferential direction between an inner ring and an outer ring, a cage ring having a plurality of pocket portions which regulate relative movement in a circumferential direction of the cam and the roller, and an annular spring which urges the cam, in which the cam has an engagement stepped portion capable of engagement with the spring, the cage ring has an end-part circumferential annular portion continuing in the circumferential direction on an end surface in the axial direction, the pocket portion regulates movement of the roller to the outer ring side and the inner ring side and has a claw portion capable of insertion of the roller from the outer ring side or the inner ring side by elastic deformation.

Claims

1. A cam clutch unit comprising a plurality of cams and a plurality of rollers disposed between an inner ring and an outer ring coaxially provided capable of relative rotation, a cage ring having a plurality of pocket portions which regulate relative movement in a circumferential direction of the cams and the rollers, and an annular spring which urges the cams, wherein the cams have an engagement stepped portion capable of engagement with the spring; the cage ring has an end-part circumferential annular portion continuing in the circumferential direction on an end surface in the axial direction; a surface of one of the pocket portions adjacent to the corresponding roller in the circumferential direction is formed having a shape which regulates movement of the roller to the outer ring side and the inner ring side and has a claw portion capable of insertion of the roller from the outer ring side or the inner ring side by elastic deformation, wherein the cage ring has a plurality of hook portions which regulate movement of the annular spring in the axial direction, and the hook portion has a hook bottom portion which regulates the movement in a radial direction of the annular spring.

2. The cam clutch unit according to claim 1, wherein the claw portion has chamfering, which facilitates insertion, on an end part on an insertion side of the roller.

3. The cam clutch unit according to claim 1, wherein the pocket portion which accommodates the roller has a contact-stop portion which regulates movement in an axial direction of the roller to the spring side.

4. The cam clutch unit according to claim 1, wherein the claw portion includes a plurality of claw portions provided in plural in an axial direction with a length smaller than an axial length of the roller.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a perspective view of a cam clutch unit of an Embodiment of the present invention;

(2) FIG. 2 is an exploded perspective view of the cam clutch unit shown in FIG. 1;

(3) FIG. 3 is a side view of the cam clutch unit shown in FIG. 1 on a spring side;

(4) FIG. 4 is a side view of the cam clutch unit shown in FIG. 1 on a side opposite to FIG. 3;

(5) FIG. 5 is a partially sectional perspective view of the cam clutch unit shown in FIG. 1;

(6) FIG. 6 is a partially sectional view of the cam clutch unit shown in FIG. 1;

(7) FIG. 7 is a partially plan view of a cage ring of a cam clutch unit according to another Embodiment of the present invention;

(8) FIG. 8 is a perspective view of a conventional cam clutch unit;

(9) FIG. 9 is a side view of the cam clutch unit shown in FIG. 8 viewed in a rotation axis direction;

(10) FIG. 10 is a side view and a front view of a cam of the cam clutch unit shown in FIG. 8;

(11) FIG. 11 is a side view and a front view of a roller of the cam clutch unit shown in FIG. 8;

(12) FIG. 12 is a partial side view and a sectional view of the cam clutch unit shown in FIG. 8;

(13) FIG. 13 is a perspective view of a cam clutch unit according to a reference example;

(14) FIG. 14 is a side view of the cam clutch unit shown in FIG. 13 viewed in a rotation axis direction;

(15) FIG. 15 is a side view and a front view of a cam of the cam clutch unit shown in FIG. 13;

(16) FIG. 16 is a side view and a front view of a roller of the cam clutch unit shown in FIG. 13; and

(17) FIG. 17 is a partial side view and a sectional view of the cam clutch unit shown in FIG. 13.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

(18) A cam clutch unit 100 according to an Embodiment of the present invention includes, as shown in FIGS. 1 to 6, a plurality of cams 130 as engagement elements which transmit and shut off a torque between an inner ring and an outer ring in an annular space between a track surface of the inner ring and a track surface of the outer ring coaxially provided capable of relative rotation, a plurality of rollers 140 which freely rotate the inner ring and the outer ring, a cage ring 150 having a plurality of pocket portions 151, 152 which regulate relative movement in a circumferential direction of the cam 130 and the roller 140, and an annular spring 160 which urges each of the plurality of cams 130 to a meshing direction with respect to the inner ring and the outer ring.

(19) Each of the plurality of cams 130 has, as shown in FIG. 2 and the like, an engagement stepped portion 131, which is engageable with the annular spring 160, on one of end surfaces in an axial direction.

(20) In this Embodiment, the engagement stepped portion 131 has an inclined shape which is a protruding part at an eccentric position, and when the spring 160 presses the protruding part of the engagement stepped portion 131, the cam 130 is urged toward the inner ring side and is urged to swing in a direction in which the cam 130 is operated.

(21) The plurality of rollers 140 do not have a groove or a stepped part as shown in FIG. 2 and the like, and in this Embodiment, an axial dimension of the roller 140 is equal to or smaller than an axial dimension of the cam 130 excluding the engagement stepped portion 131.

(22) In this Embodiment, outer-peripheral edge parts on both end surfaces of the roller 140 are chamfered, which smoothens insertion of the cam clutch unit with respect to the inner/outer ring.

(23) The cage ring 150 has the pocket portion 151 which accommodates the cam 130 and regulates relative movement in the circumferential direction as well as the pocket portion 152 which accommodates the roller 140 and regulates relative movement in the circumferential direction and a plurality of hook portions 153 which regulate movement in the axial direction of the annular spring 160.

(24) The cage ring 150 has an end-part circumferential annular portion 155 continuing in the circumferential direction on an end surface on the hook portion 153 side in the axial direction and an end-part circumferential annular portion 156 continuing in the circumferential direction on the end surface on a side opposite thereto (rear surface side) and is constituted so that rigidity of the entire cage ring 150 is improved by a member in the axial direction forming each of the pocket portions 152 being supported on both sides.

(25) In this Embodiment, the pocket portions 151 of the cage ring 150, which accommodate the cams 130, are uniformly disposed at 8 spots and the pocket portions 152 which accommodate the rollers 140 at four spots.

(26) Moreover, a surface on the cam side of the end-part circumferential annular portion 155 constitutes an end surface on outer sides of the plurality of hook portions 153 and a surface on the cam side of the end-part circumferential annular portion 156 constitutes a contact surface in the axial direction of the cam 130, the roller 140 in each of the pocket portions 151, 152.

(27) In each of the pocket portions 151, 152, the cam 130 and the roller 140 have the movement regulated by the spring 160 on the one of end surface sides in the axial direction and the movement to the other side in the axial direction is regulated by the end-part circumferential annular portion 156 on the rear surface side.

(28) Moreover, the surface adjacent to the roller 140 of the pocket portion 152 which accommodates the roller 140 is formed having a shape which regulates movement of the roller 140 to the outer ring side and the inner rig side.

(29) Furthermore, on the surface adjacent to the roller 140 of the pocket portion 152 accommodating the roller 140, a claw portion 157 capable of insertion the roller 140 from the outer ring side by elastic deformation is provided.

(30) In this Embodiment, as shown in FIG. 6, the claw portion 157 is chamfered on the end part on the insertion side in order to facilitate the insertion of the roller 140, and by setting an interval tw=3.7 mm at distal ends of the opposing claw portions 157 with respect to a diameter T=4.145 mm of the roller 140, and an angle =30 with respect to a tangent by the chamfering in a straight-line sectional state, facilitation of the insertion and maintaining after the insertion are both realized.

(31) Moreover, as shown in FIG. 2, the cage ring 150 has the hook portion 153 which regulates the movement of the annular spring 160 in the axial direction, and the hook portion 153 has a hook bottom portion 154 which regulates the movement of the annular spring 160 in the radial direction.

(32) As a result, the roller 140 does not restrict tension of the spring 160 at all, and the spring 160 presses the protruding part at an eccentric position of the engagement stepped portion 131 of the cam 130 and thus, each of the cams 130 is independently pressed in the vicinity of the center of the spring 160 extended between the two hook bottom portions 154, whereby a uniform and highly accurate operation can be performed without being influenced by the change in the attitude of the other cams 130.

(33) It is to be noted that, in this Embodiment, the eight cams 130 and the four rollers 140 are in the same numbers and are alternately disposed, but the number and the disposition of each of the cams 130 and the rollers 140 and may be arbitrary.

(34) Moreover, the shape of the cam 130 may be arbitrary and may be a sprag shape, for example.

(35) Moreover, a height in the radial direction of each of the hook bottom portions 154 may be uniform or may be different depending on a position in the circumferential direction.

(36) By setting the height of the hook bottom portion 154 depending on the number, disposition of each of the cams 130 and the rollers 140 as appropriate, similarly to the aforementioned Embodiment, each of the cams 130 can perform the uniform and highly accurate operation.

(37) The cam clutch unit according to another Embodiment of the present invention has, as shown in FIG. 7, a contact-stop portion 158 which regulates movement in the axial direction of the roller 140 to the spring 160 side on the pocket portion 152 accommodating the roller 140.

(38) As a result, contact between the roller 140 and the spring 160 can be completely eliminated, and rotational resistance can be further reduced.

(39) Moreover, the claw portion 157 provided on the surface adjacent to the roller 140 of the pocket portion 152 accommodating the roller 140 does not continue in the axial direction of the roller 140 but is provided by being divided into plural.

(40) In this Embodiment, they are provided in the vicinity of both end parts in the axial direction of the roller 140, but the spots thereof, the number of divisions, and the length in the axial direction may be designed arbitrarily or may be different between the opposing surfaces.

(41) The Embodiments of the present invention have been described in detail, but the present invention is not limited to the aforementioned Embodiments but are capable of various design changes without departing from the present invention described in the scope of claims.

(42) For example, in the aforementioned Embodiments, the engagement stepped portion capable of engagement with the spring is provided on one of the end surfaces in the axial direction of the cam, but it may be so configured that the cam has the engagement stepped portion provided at the center as conventional, the spring is extended at the center part in the axial direction, and the plurality of rollers are inserted with the spring sandwiched into the pocket accommodating each of the rollers.

(43) Moreover, it may be so configured that the engagement stepped portion is provided on both end surfaces in the axial direction of the cam, and the hook portion is provided on both sides in the axial direction of the cage ring and is urged by two annular springs.