GB756367A - Improvements in and relating to latching devices - Google Patents

Abstract

756,367. Locking devices. ENGLISH ELECTRIC CO., Ltd. Sept. 24, 1954, [Sept. 25, 1953], No. 26470/53. 'Class 80(3) [Also in Group XXXVII] To prevent the rebound of a moving member, e.g. the moving contact carrying member 13 of a circuit-breaker, on the impact of stops 25, 26 when the member 13 reaches the limit of its movement, a movable latch 28 is arranged to enter into engagement with a co-operating locking member 27, biasing means causing their disengagement after an interval at least sufficient for the member 13 to come to rest. In Fig. 1, when the catch 15 is disengaged from the detent 16, the member 13 is opened by the spring 24. Just before the impact of the stops 25, 26, the pin 27 strikes a face 28a of the latch 28 causing the latch to turn about its pivot 29 so bringing a locking face 28b behind the pin 27 to prevent any rebound of the member 13 other than that due to the small clearance between the parts 27, 28b. When the member 13 is at rest, the latch 28 is disengaged by. gravity. A pin 30 passing through a slot in the latch limits the angular movements of the latch. In an alternative arrangement, Fig. 5, the latch 32 is pivotally mounted on the member 13 and is caused to engage with the fixed pin 34 by its own inertia when the member 13'is arrested at the end of its travel. In this arrangement, a spring 35 disengages the latch when the member 13 is at rest and the stops 25 and 26 may be resiliently mounted to increase the duration of the impact to ensure correct engagement of the latch