Abstract: A one-way clutch includes multiple rollers, a first collar and a second collar that are concentric and rotate relatively to each other, and a circular holding frame. The first collar has multiple cavities each having an inclined bottom surface. The circular holding frame has multiple slots corresponding to the rollers and exposing the cavities. The second collar is rotated to drive the circular holding frame rotating through friction force so that each roller is pushed to contact a higher portion of the inclined bottom surface and also the second collar drives the first collar rotating via pushing of the rollers. When rotational speed of the first collar is greater than that of the second collar, each roller enters a lower portion of the inclined bottom surface and separates from the second collar without transmitting torsional force between the second collar and first collar.

Abstract: A one-way clutch includes multiple rollers, a first collar and a second collar that are coupled together to form relative rotation between them, and a circular holding frame. The first collar has multiple cavities each having an inclined bottom surface. The circular holding frame has multiple slots corresponding to the rollers and exposing the cavities. The second collar is rotated to drive the circular holding frame rotating through friction force so that each roller is pushed to contact a higher portion of the inclined bottom surface and also the second collar drives the first collar rotating via pushing of the rollers. When rotational speed of the first collar is greater than that of the second collar, each roller enters a lower portion of the inclined bottom surface and separates from the second collar without transmitting torsional force between the second collar and first collar.

Abstract: A bearing structure, for example of a needle roller bearing, has an outer surface defined in part by a composition comprising a first polymeric material having a Rockwell hardness (m scale) in the range 80 to 130. Preferred materials are polyaryletherketones, for example polyetheretherketone.