GB841071A - Improvements in and relating to hydraulic control systems - Google Patents

Abstract

841,071. Hydraulic brakes. CITROEN S.A., A. June 14,1957 [July 19,1956], No. 18910/57. Class 103 (1). [Also in Group XXIX] In an automatic clearance adjustment device for an hydraulic control system, e.g. an hydraulic braking system, a hollow body 1 having a chamber 2 filled with hydraulic fluid is connected with the movable member to be controlled and a differential piston 8 is adapted to move to a predetermined limited extent within this chamber, the rear face of the piston being subjected to the pressure of the fluid fed through pipe line 10 from a source of fluid under pressure; the pipe line 10 also being connected with a chamber 2 through a non- return valve 11 permitting the ingress of hydraulic fluid into the chamber after the clearance has been taken up. The brake arrangement illustrated indicates a disc brake having an hydraulic cylinder 4 in which piston 5 is operatively connected to axially slidable brake lining pressure plate 5 against the force of return springs 13. When fluid from a pressure source is fed into pipe line 10, differential piston is displaced downwardly until it reaches its abutment such that a volume of liquid V has been displaced from chamber 2 into the cylinder 4 and other cylinders (if any) through pipe line 3<SP>1</SP> to take up the clearance of the brake. Further pressurization of the fluid in line 10 lifts spring-loaded valve 11 off its seat and allows fluid to pass into chamber 2.