| 摘要 |
A reset mechanism for a stop-watch is operable to rotate two cams on the staves of the minute and second hands respectively of the watch, back into datum angular positions. Depression of a reset button of the mechanism actuates an operating lever that engages with a cam surface of a pivotally-mounted support-member to pivot the support member towards the cams against the action of a spring. A striker of unitary construction and having camming surfaces for engaging the cams is pivotally mounted on the support member but is restrained from more than small angular displacement relative to the support member by a pin which from the striker member engages in an oversized hole in the support member. Pivoting of the support-member carries the striker to bring its two camming-surfaces into engagement with the two cams respectively, the loose mounting of the striker on the support member permitting it limited adjustment of orientation relative to the support-member to ensure that the camming surfaces are both brought into positive engagement with their respective cams. The striker is constrained to movement along a path which is defined by a slot in the base plate of the mechanism and which is spaced from the support-member pivot, the slot being engaged by a pin which is carried on the striker and which is spaced from the pivot of the striker with the support member. |
