GB1288030A - - Google Patents

Abstract

1288030 Aritiskid braking systems GOODYEAR TIRE & RUBBER CO 22 Oct 1970 [18 Nov 1969] 50114/70 Heading F2F An electrical signal, directly proportional to the brake pedal force is compared with a further signal, the amplitude of which is inversely proportional to the amount of skidding, and the lower of the two currents drives a valve 40 to decrease the hydraulic pressure supplied to a brake 44 for a rotating element 46. As shown, two pedals 10, 12 for different operators may be provided each of which actuates a pair of linearvariable differential transformers 18-18a and 20-20a respectively providing A.C. signals, of an amplitude directly proportional to the pedal force, which are rectified in rectifiers 22, 24, amplified at 26, 28 and fed to a circuit 30 that transmits only the higher of the two signals. The higher signal is fed to a circuit 36 having a second input which is an antiskid signal 52 which decreases in proportion to the amount of skidding by the provision of a shunt 56 and current to voltage circuit 58 which is fed with a current from a constant current source 54. When a skid develops signal 52 causes shunt 56 to divert from source 54 a current directly proportional to the amplitude of the antiskid signal. The output of circuit 58 is then zero and this is recognized as the lowest of the two inputs to a circuit 36 and is the controlling signal for valve 40. If the force on pedals 10, 12 is reduced so that the brake pressure is below the skid threshold, valve 40 once again becomes controlled by the braking circuits. Pedals 10, 12 are provided with springs 14, 16 which simulate the pedal action of a completely hydraulic braking system.