Koyo Seiko Company, Ltd.

Tomomasa Kubo

Yoshihisa Miura

Tetsuaki Numata

Satoshi Fujiwara

A one-way clutch includes a retainer ( ), a spring ( ), and sprags ( ) which are provided in pockets of the retainer and those of the spring in a pivotable manner and forced by tongue-like flaps formed in the spring in a direction in which the sprags ( ) are to be locked. A peripheral maximum width (La) of an outer cam surface of the sprag ( ) and a peripheral maximum width (Lb) of an inner cam surface are greater than a circumferential width (Lp) of the pocket of the retainer ( ). Further, a width (Lc) of the sprag ( ) in the direction of inclination is made smaller than a circumferential width (Lp) of the pocket of the retainer ( ).

One-way clutch

In a one way clutch, a sprag does not always turn around a center of curvature thereof, failing to move smoothly because the sprag contacts an outer ring and an inner ring on the surface. Accordingly, switching from idle rotation to locking of the clutch may cause hopping or the like of the sprag which will pop out of place to be broken. The present invention has an object to provide a one way clutch capable of allowing the stable motion of the sprag if the sprag should hop during pivotal movement and offering an increased freedom of design of a retainer and a ribbon spring. For achieving the object, a one way clutch comprises an annular space defined between an outer ring and an inner ring, sprags, a retainer and a spring, characterized in that the sprag comprises a cam surface contacting an inner circumferential surface of the outer ring, a cam surface contacting an outer circumferential surface of the inner ring and a protrusion opposing a wall surface of a pocket of the retainer. The latter cam surface and the protrusion are configured such as to have the respective curvature centers positioned at the same center of turning. On the other hand, the cam surface contacting the inner circumferential surface of the outer ring is configured to turn about the curvature center thereof positioned in the vicinity of the curvature center of the cam surface and protrusion.

One way clutch

A one-way clutch according to the present invention comprises an outer race fitted in a housing member, an inner race, a plurality of engaging members arranged between the outer race and the inner race, a cage for holding the engaging members, a spring for biasing each of the engaging member in one direction, annular members arranged on the opposite sides of the outer race so as to close a space between the inner and outer races, said inner race being formed of metal, one of said annular members being formed of synthetic resin, and an integral molding means for integrally forming the inner race and the annular member. According to a further embodiment, one annular member and the cage are integrally molded with synthetic resin.

Growing community of inventors

Kashiwara, Japan

Tomomasa Kubo