| 摘要 |
840,034. Automatic circuit - breakers; mechanical switches. MECHANICAL PRODUCTS Inc. Nov. 5, 1956 [March 5, 1956], No. 33749/56. Class 38 (5). An automatic circuit-breaker has a moving contact assembly which is normally latched by a current-responsive bimetal or trimetal latch 21 to an actuating- member 37 normally retained in the closed position by a second mechanical latch comprising an apertured fixed cage 65 housing balls 63 which are urged into engagement with a detent 61 in the member 37 by pivoted levers 67. Springs 25, 73 are connected between the levers 67 and pivoted contact carrying levers 17. When an overload occurs, the latch 21 disengages from an abutment 34 on the member 37 and permits the springs 25, 73 to pull down the moving contact assembly to open contacts 13, 15. The opening of the contacts causes the springs 25, 73 to return to their unstressed state so removing the spring bias from the levers 67 and balls 63. This permits a spring 51 to move the actuating member 37 down into the off position, so enabling the latch 21 to reset on cooling. The contacts may then be reclosed by pushing the knob 54. The contacts may be opened manually by pulling the knob 54 so that the detent 61 cams the balls 63 outwardly from the member 37 to permit the member 37 to move to its off position without disengaging the latch 21. Specification 756,764 is referred to. |
