GB1316278A - Descent device - Google Patents

Abstract

1316278 Safety lowering apparatus J L ELMER 3 May 1971 [3 Feb 1970] 5072/70 Heading B8B [Also in Division E2] A controlled speed descent device comprises a rotatable wheel 10 engageable by an escape line 1 achored to an elevated point of a building or structure and means for controlling rotation of the wheel such that it rotates at a substantially constant speed when a load is applied to the device or the line. The wheel 10 rotatably mounted in a casing 14, is serrated and the line is biased by springs 36 into engagement therewith, an extension shaft of the wheel mounting centrifugally displaceable brake pads engageable with a brake drum rigid with the casing 14. Part of the casing 14 with the springs 36 is manually displaceable to permit insertion or removal of the line to and from the device, a spring catch 40 locking an operating arm therefor to a static arm 38 on the casing. A slip ring is roller mounted around the brake drum to engage and ride over any passing projection and prevent fouling of the device. A harness 42 depends from the device and is associated with both said arms such that locking together thereof is assisted by the load on the harness. In the embodiment of Figs. 8 and 9 (not shown) movement of the device along the line is variably controlled by a clockwork mechanism and the line engaging wheel is formed as a sprocket with the teeth engaging indents in a tape replacing the line. In the embodiment of Figs. 2 and 3 (not shown) the device is secured to a line reel to restrict downward velocity of the reel as it pays out line anchored at its upper end to a building or the like.