IMPROVEMENTS IN HYDRAULIC ANTI-SKID BRAKING SYSTEMS FOR VEHICLES

摘要

In a modulator assembly of the kind including a dump valve operable by skid sensor to cause closure of a valve to isolate a master cylinder from a brake and initiate operation of a pump, the modulator assembly incorporates a time-delay piston of differential outline working in a stepped bore in a housing. The piston is exposed a its end of smaller area to pressure in the master cylinder which is applied to the brake through a flow-control regulator valve and at its end of greater area to pressure in an expansion chamber through fixed outline . Equalization of the pressures acting on the piston causes the piston to move in a direction to open the regulator valve whereby to ensure that fluid from the master cylinder can flow to the brake at a rate faster than the rate at which it is returned from the brake by the pump.