Individual fire escape from high rise building - has cable descent speed controlled by friction spring brakes with centrifugal arms

摘要

An individual fire escape has a housing (1) containing a spindle (2) and a drum (3) carrying the descent cable (4). At the other end is a plate (20) with a hub (6) with inclined slideways (14) cut around its periphery. These retain L shaped spring blades (16, 17) on sliding blocks (13). Each block is connected to a pivot arm (24) having a weight (26) on the end. As the cable unwinds, the blades, supported by a pin (18) under the corner, pass under a roller (22). The friction effect controls the rate of descent. This is regulated by the weighted arms, moving under centrifugal force, altering the relative curvature of the blades.