Braking systems for vehicles

Claim 2

A braking system for a vehicle wheel, comprising in combination circuit means producing an output dependent upon the rate of change of rotational speed of said wheel, an amplifier coupled to said circuit means, said amplifier operating when the deceleration of the wheel exceeds a predetermined value to release the brakes from said wheel, an inhibiting circuit coupled to said circuit means, said circuit means providing a triggering input to said inhibiting circuit when the acceleration of the wheel exceeds a set value, delay means within said inhibiting circuit, said delay means holding said inhibiting circuit in a triggered condition for a predetermined period after said triggering input is removed, and means whereby said inhibiting circuit when in said triggered condition prevents release of said brakes by said amplifier.

Claim 3

A system as claimed in claim 1 in which said inhibiting circuit includes a transistor which is biased to conduction, said circuit means turning said transistor off when the acceleration of the wheel exceeds said set value, and said delay means comprising a capacitor associated with said transistor, said capacitor charging when said transistor is turned off, but maintaining the inhibiting circuit in its triggered condition for said predetermined period.

Claim 4

A braking system for a vehicle wheel, comprising in combination means producing an electrical signal representing the rotational speed of the vehicle wheel, a differentiating circuit to which said signal is applied, said differentiating circuit producing an output representing the rate of change of rotational speed of the wheel, an amplifier operable by the output from said differentiating circuit to release the brakes from the wheel when the rotational deceleration of the wheel exceeds a predetermined value, a transistor, circuit means biasing said transistor to conduction, means operable when said transistor is non-conductive for inhibiting said amplifier to prevent release of said brakes, a capacitor associated with said transistor, said transistor when conductive holding said capacitor discharged, but said capacitor charging when said transistor turns off, means coupling said transistor to said differentiating circuit, said differentiating circuit producing an output to turn said transistor off when the acceleration of said wheel exceeds a set value, said capacitor then charging, and said capacitor serving when said transistor is no longer biased off by the output from the differentiating circuit to hold said transistor off for a predetermined period of time.

Claim 5

A braking system for a vehicle wheel, comprising in combination means producing an electrical signal representing the rotational speed of the vehicle wheel, a differentiating circuit to which said signal is applied, said differentiating circuit producing an output representing the rate of change of rotational speed of the wheel, an amplifier operable by the output from said differentiating circuit to release the brakes from the wheel when the rotational deceleration of the wheel exceeds a predetermined value, a transistor, circuit means biasing said transistor to conduction, means operable when said transistor is non-conductive for inhibiting said amplifier to prevent release of said brakes, a capacitor associated with said transistor, said transistor when conductive holding said capacitor discharged, but said capacitor charging when said transistor turns off, means coupling said transistor to said differentiating circuit, said differentiating circuit producing an output to turn said transistor off when the acceleration of said wheel exceeds a set value, said capacitor then charging, and said capacitor serving when said transistor is no longer biased off by the output from the differentiating circuit to hold said transistor off for a predetermined period of time.