| 摘要 |
<p>The timing mechanism has a lever movement (22) pivoted at position B, on a movement plate, designed to occupy three positions and is controlled by two mechanisms. A control mechanism (26), in particular the column wheel (3), sets the first and second positions of the lever. A first 'second hand stop' position in the lever end (24a) is engaged in the circle traversed by the teeth points of the gear (8) and thus blocks the rotation of the gear and the rotation of the second hand (6). A second 'second hand working' position in the lever end (24a) is entirely disengaged from the teeth of the gear (8) and permits the gear to turn for each pulse of the escape movement and to thus drive the second hand(6). -. A second mechanism(28) sets the third ' second hand zero reset' position of the lever(22), and includes a part(50) which moves between two positions, one active the other inactive. The part(50) consists of a strip which slides over the surface of the movement. It has a first end (52) which co-operates with an exterior push-button (54) and a second end(56) whose face (56a) is designed to act on the end (24c) of the lever (22) when the button (54) is pushed. The strip (50) is guided by two pins (58) fitted in slots (60) formed in the strip.</p> |
