| 摘要 |
1406784 Mechanical switches AMP Inc 20 March 1973 [13 April 1972] 13308/73 Heading H1N A switch, Fig. 3, includes an insulating rotary cam operating member 30 having stop shoulders 60, 70 co-operating respectively with surfaces 80, 79 of an insulating housing 34 to define first and second cam positions, and resilient contacts 10, 12 which are acted upon against their resilient bias by cam surface projections 66, 62. In the second cam position shown by Fig. 3, following clockwise rotation of the cam, projection 66 is biased by contact 10 and projection 62 is biased by contact 12 with the nett resultant turning moment holding the switch in the open condition. In the first cam position (Fig. 5, not shown) anticlockwise rotation of cam 30 causes projection 62 to be disengaged from contact 12 and the contacts 10, 12 to be held in biased engagement with one another by virtue of their overlapping relationship and the registration of projection 66 in the detent recess 14 of contact 10 with a nett turning moment to hold the contacts closed. In an interim position (Fig. 4, not shown) both contacts have been moved to an extreme position and a wiping action is obtained during their engagement. Fig. 2 gives an exploded view of a single switch unit of a multiunit assembly in which the contacts have recesses 18, 24 for registration with projections formed on the base 2, upstanding walls 4 form a compartment for the switch, slots 26 form bearing surfaces for the cam shaft 28 and a cover 34 for snapping over latching portions 6 to retain the assembled parts in position. The cam 30 has faces 52, 54 which protrude through the cover to act as a rocker type operating member and holes 76 provide for locking wires. The contacts 10, 12 terminate in extensions 16, 22 which are spaced suitably for engagement with a printed circuit board 44. |
