GB1004136A - Fluid pressure braking system - Google Patents

Abstract

1,004,136. Fluid pressure brakes. D.B.A. S.A. March 11, 1963 [March 14, 1962], No. 9579/63. Heading F2F. A vehicle brake control for distributing the braking pressure between the front and rear wheels in proportion to the load on the wheels comprises two valves 46 (only one shown, Fig. 2), or master cylinders controlling braking pressure to front and rear brakes 30, 30<SP>1</SP> and operated by a pedal 24 through a spring 96, rod 90, a lever 66, balls 68 and tappets 62, each ball 68 (only one shown) being carried in the end of a piston rod 72 which is moved axially to vary the mechanical advantage of the linkage by supplying pneumatic pressure to a cylinder 82 from the suspension system and thus automatically varying the braking pressure in accordance with vehicle load. As shown a pump 16 supplies pressure liquid to accumulators 26, 26<SP>1</SP> of front and rear braking circuits 32, 34; 32<SP>1</SP>, 34<SP>1</SP> controlled by the valves 46. Each valve comprises a plunger 46, a doubleheaded valve member 48 and a balanced guide member 50 and the members are biased by springs 52, 58 to the position shown wherein the valve member 48 closes a part between the pressure supply line 32 and the brake line 34 and opens a port 56 between the brake line 34 and exhaust line 33. On depression of the brake pedal 24 the force transmitted to the arm 66 is divided into two forces inversely proportional to the distance between the pivot 88 of the arm 66 and the balls 68, which forces act on the valves 46 to move down the valve members 46, 48, 50 and thus close the exhaust port 56 and open the port between the pressure and brake lines 32, 34. The braking pressure supplied to the brakes increases until the reactive pressure on the plunger 46 equals the applied force. On release of the pedal 24 the brake line 34 is exhausted through the exhaust port 56 and line 33.