| 摘要 |
<p>In order to provide a ratchet which can be made from inexpensive parts, it comprises a pair of discs (5 and 6) having ramps (5a, 6a) upset from a peripheral zone of the discs and terminating in shoulders (5b, 6b). The discs are loaded together by a spring 9 which enables the drive to be transmitted via the faces of the ramps (5 and 6) up to a predetermined limit before the discs separate and the ratchet clicks over. In the opposite direction the drive is transmitted through the shoulders (5b, 6b), which may then be inclined to provide a torque limitation. The ratchet may for example be used in wheel braces (as illustrated in Figure 1) or in spark plug spanners.</p> |
