GB676834A - Improvements relating to hydraulic pressure transmission systems - Google Patents

Abstract

676,834. Hydraulic brakes. FIAT SOC. PER AZIONI, and BALDWIN, P. S. May 3, 1950 [May 4, 1949; April 21, 1950], No. 10925/50. Class 103 (i). In a master cylinder for hydraulic brakes, when the pressure is being supplied to the brake cylinders through connection 2, the connection 3 to the reservoir is sealed off by means of freely floating valve elements 4, 5, 6 located between the end of the cylinder and a stopring 9, which may be a spring ring of annular form. In the construction shown in Fig. 3, the valve element 4 is an elastic ring of smaller diameter than the cylinder bore, the ring 5 a metallic spacer element, and element 6 an elastic sealing ring having a convex outer surface of maximum diameter normally slightly greater than the cylinder bore. Located between element 4 and the stop-ring 9 is a cup-like thrustmember 16 having in its end a reduced bore of such size that when the piston 12 is operated to apply the brakes the resistance of the fluid to flow through the bore is such that the member 16 is moved and compresses the elements 4, 5, 6 sufficiently to seal off the reservoir connection 3. In Fig. 5 there is a plunger shaft 17 of smaller diameter than the cylinder bore and the thrust member is in the form of an axially-bored piston 25. Fig. 7 shows a similar arrangement with a normal size piston 12 and in both Figs. 5 and 7 the pressure-fluid passes out of the brake cylinder connection 2 without having to pass through the restriction in the thrust member.