| 摘要 |
<p>A sprag clutch having inner and outer concentric races (1, 2) with sprags (3) pivotally located between the races (1, 2). A circumferential garter spring (6) locates over the sprags (3) to bias them to a wedging position. Relative rotation of the races (1, 2) in one direction causes a centrifugal force (CF) to act on each sprag (3) to pivot it away from contact with the outer race (2). The centre of gravity (G) of each sprag (3) is located radially inwards of its centre of rotation (C) such that when the sprag (3) pivots the centrifugal couple (CF) increases to overcome the increased tension couple (SF) of the garter spring to allow a snap action lift off of each sprag (3). The snap action substantially reduces the contact time between the sprags (3) and the outer race (2) and hence wear is reduced.</p> |
