Braking pressure regulating device for a vehicle braking system

In a wheeled vehicle braking system of the type wherein braking pressure is applied to wheel cylinders of the vehicle wheels in response to pressure applied to a brake pedal and transmitted through a master cylinder, the improvement of a regulating device by which the braking pressure applied to the wheel cylinders is controlled in a fashion to ensure that the rate of reduction of the wheel speed corresponds to a deceleration rate set by the magnitude of the pressure applied to the brake pedal, said regulating device comprising:

• sensor means for detecting the rotational speed of at least one wheel of said vehicle and developing a wheel speed-responsive voltage representative thereof;
• memory means for storing said speed-responsive voltage, siad voltage being discharged in response to the application of braking pressure to said brake pedal;
• proportioning means operatively connected through said master cylinder to said brake pedal for setting the rate of discharge of said voltage in response to the magnitude of braking pressure applied to said brake pedal;
• comparator means for comparing said discharge voltage with said wheel speed-responsive voltage when said at least one wheel is being braked under said braking pressure;
• and
• pressure increasing means including a cut-off means for interrupting communication between said master cylinder and said wheel cylinders, said pressure increasing means supplying a pressure of a magnitude greater than that of the master cylinder pressure to said wheel cylinder when said wheel speed-responsive voltage is higher than said variably responding discharge voltage, thereby decreasing said wheel speed and ensuring that the rate of reduction of said wheel speed corresponds to the rate set by the pressure applied to the braking pedal.