| 摘要 |
<p>A hand wheel 10 for a nursery gate frame adjustment mechanism comprises a ratchet member 12 received in a housing. The ratchet member 12 has respective ratchet surfaces 24, 26 on opposite faces thereof. A screw-threaded bore 22 is formed through the ratchet member 12. The housing has a first part 14 for co-operating with the ratchet surface 24 on one face of the ratchet member 12 and a second part 16 for co-operating with the opposite ratchet surface 26 on the other face of the ratchet member 12. A compression spring 18 biases the ratchet member 12 towards the first part of the housing. In that way the hand wheel 10 rotates the ratchet member 12 in one direction by engagement of the first part 14 with the ratchet surface 24. In order to rotate the ratchet member in the opposite direction, the housing and ratchet member must be moved relative to each other against the bias of the spring 18 so that the second part 16 of the housing engages the ratchet surface 26. <IMAGE></p> |
