GB573513A - An improved safety device for road and rail vehicles and aircraft - Google Patents

Abstract

573,513. Emergency door fastenings. PRESSED STEEL CO., Ltd., and WIGHTMAN, C. Sept. 10, 1943, No. 14855. [Class 44] In an emergency fasting for the doors of vehicles or aircraft wherein the bolt is positively released from the striking plate or keeper in the event of abnormal change of motion in any direction such as might occur in a crash, a spring-loaded plunger mounted in the door joint is held retracted by a trigger under control of a pendulum and, when released, is projected into the keeper to thrust the bolt therefrom. As shown a U-form frame 19 is mounted in the door jamb adjacent to the striking plate 16 with which the bolt 15 engages, and provides bearings for a plunger comprising a tail 24 surrounded by a compression spring 29, a nose plate 25, and an intermediate gapped plate 23. The plunger is normally held retracted by the hooked end 33 of a lever pivoted on frame 19 at 32, held up to engagement by a spring 38 which can be adjusted by screw 39. Resting in a hemispherical seat in a fixed bracket 37 is a hemispherical me nber 36 from which depends a weight 35. The flat upper face of member 36 is in contiguity with the arm 31 of the detent lever. With a sufficiently violent change of vehicle motion member 35 can swing from its normal position, raising arm 31 against the action of spring 38 and releasing plate 23 from engagement by hook 33. Spring 29 then shoots the plunger to project plate 25 through registering slots in member 19, door jamb 14, and striking plate 16 to thrust the bolt 15 clear of plate 16. In a modification spring 38 is omitted and the pendulum member is in the form of a hollow cone suspended on the upper end of a vertical pin situated below and near the hook end of the detent lever. This lever is held up to engagement by a pin projecting upwards from the apex of the cone and in contact with the lower end of a pin depending from the lever. When the pendulum swings its pin moves out of contact and alignment with the detent pin. The engaging face of the detent hook is inclined so that spring 29 shoots the plunger, the detent lever being cammed out of engagement. In a further modification for the simultaneous control of several vehicle doors by a single pendulum device, the pendulum, placed in any suitable position, normally holds a spring-loaded contact lever in " open " position and the detents of the plungers mounted in the door jambs are in the form of solenoid cores. The circuits of the solenoids are closed, retracting the cores to release the plungers, when the pendulum moves from normal position, freeing the contact lever. To facilitate opening of the doors their edges 13 may be inclined as shown.