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US 3,942,843 AGranted
Method of braking a vehicle having an antiskid brake circuit, and a modulator for such a circuit
AssigneeSociete Anonyme D.B.A.
InventorAndre Tobiasz
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AssigneeSociete Anonyme D.B.A.
InventorAndre Tobiasz
Estimating the term…
A method of braking a vehicle having an antiskid brake circuit of the type having a modulator of which the modulator chamber is connected to a set of brake actuators, and a plunger projecting into the chamber, the plunger being moved by way of a driving assembly operated by a motor driven by an antiskid control device, responsive to rotary motion of the vehicle. The curve ploting the variation with time, in the volume of the modulation chamber from the position of maximum penetration by the plunger follows substantially the same course as the absorption curve for the set of brake actuators connected to the modulator. This absorption curve represents the increase in pressure in the brake actuator as a function of the increase in the volume of fluid contained in the brake actuator. A hydraulic pressure modulator for an antiskid brake circuit for a braked vehicle which comprises a housing containing a modulation chamber capable of being connected to a set of brake actuators for a vehicle and a plunger slidable in the housing and projecting into the chamber. The plunger is moved by way of a driving assembly operated by an antiskid control device responsive to rotary motion of at least one wheel of the vehicle, so as to permit variation of the braking pressure in the brake actuators. The driving assembly comprises a mechanical transmission with a cam driven by a continuously rotating electric motor. The angular motion of the cam in a given direction is associated with motion of the plunger in a given direction; whereas angular motion of the cam in the opposite direction causes motion of the plunger in the opposite direction. Each angular movement of the cam is responsive to rotation of the motor, said rotation being controlled by a signal generated by the antiskid device.
In a vehicle antiskid braking system, a modulator comprising a housing defining a modulating chamber therewithin, said housing having an inlet and an outlet communicating said modulating chamber to a pressure source and to the brakes of the vehicle respectively, valve means within said housing for controlling communication between the inlet and outlet, a plunger slidably mounted in said modulating chamber for controlling the fluid pressure level at said outlet, said plunger being shiftable between first and second positions to hold said valve means open when the plunger is disposed in the first position, said valve means closing when the plunger is moved away from the first position, driving means for actuating said plunger, said driving means including a rotatable cam operably connected with said plunger, an electric motor for driving said cam, said motor normally driving said cam in a normal direction moving said plunger to said first position, control means for detecting an incipient skidding condition of a vehicle wheel and operatively connected to said motor, said motor being responsive to said control means to drive said cam in a direction reverse to said normal direction when an incipient skidding condition is detected to thereby drive said plunger away from said first position, and switch means operatively connected to said cam for terminating rotation of the latter when said plunger reaches either said first or said second positions.
Dependencies are inferred from the claim text.