| 摘要 |
<p>A ratchet wrench comprises an output drive member (13, 37) rotatable about a first axis, a drive housing (15) containing the output drive member, and a handle (14) on the drive housing for rotating the drive housing about the first axis. A rotary member (24) within the handle is rotatable about a second axis and a drive ring (21) extends around the output drive member. A coupling means (25) couples the rotary member to the drive ring so that rotation of the rotary member about the second axis causes rotation of the drive ring about the output drive member. The wrench also includes primary ratchet means (17, 42) for selectively uni-directionally coupling the output drive member to the housing, and secondary ratchet means (23, 43) for selectively uni-directionally coupling the output drive member to the rotary member through the drive ring whereby the output drive member (13, 37) can be rotated in a selected direction either by rotation of the handle (14) or by rotation of the rotary member (24).</p> |
