ARBETSFORFARANDE FOR EN ELEKTROMOTORISK BROMSMANOVERANORDNING, SPEC VID SKENFORDON OCH EN ANORDNING FOR UTFORANDET AV FORFARANDET

摘要

An electromechanically reciprocable load has a driving spring tending to displace it from a retracted position into a working position upon the release of a locking brake. The spring force is opposed by the countervailing force of an electric motor which, during the working stroke, is progressively reduced in keeping with the diminishing force of the relaxing spring. When the load includes a caliper of a power brake arresting a rotary element in its working positon, the motor is controlled by a bridge circuit with two potentiometers whose wipers are entrained, with a relative lag, by the load so as to establish a variable null position advancing with progressive wear of the brake linings in order to keep constant the travel of the load during a return stroke brought about by the energization of the electric motor with an overriding signal. An accelerometer monitors the speed of the rotary element to soften the impact of sudden deceleration in the final phase of the brake-actuating stroke by temporarily increasing the countervailing motor force if the rate of deceleration exceeds a predetermined threshold.