Patent ID: 8322800

Claim:
Braking control system for automotive vehicles comprising a braking control member ( 1 ), a brake booster ( 4 ) which comprises a vacuum chamber ( 40 ) and a working chamber ( 41 ) separated by a servomotor piston ( 42 ), said brake booster ( 4 ) being operable to provide increased braking control according to the difference in pressure existing between said two chambers, a brake master cylinder ( 5 ) receiving increased braking commands from the brake booster ( 4 ) and producing a braking pressure in the hydraulic braking circuit ( 6 ) of the vehicle, the system further comprising a simulator ( 3 ) coupled one of pneumatically and hydraulically to the piston ( 42 ) of the brake booster ( 4 ), said simulator ( 3 ) receiving at least one braking command from the braking control member ( 1 ) and being operable to one of establish and monitor, in return, a difference in pressure between the vacuum chamber ( 40 ) and the working chamber ( 41 ) of the brake booster so as to control the displacement of the piston ( 42 ) characterized in that said simulator ( 3 ) comprises a hydraulically controlled pneumatic three-way valve operable to: the event of a braking command initiated by the braking control member ( 1 ), to put the working chamber ( 41 ) in communication with a greater pressure than that of the vacuum chamber ( 40 ) to control operation of the brake booster and, as a result, actuation of the master cylinder ( 5 ), and when the pressure in the hydraulic braking circuit ( 6 ) of the vehicle exceeds a pressure threshold, to stop the communication of the working chamber ( 41 ) with said pressure which is greater than that of the vacuum chamber, characterized in that a control piston ( 31 ) is hydraulically controlled by the braking control member ( 1 ) and operable to control displacement of a probe ( 32 ), characterized in that the three-way valve comprises: an axially mobile probe ( 32 ), an axially mobile check valve ( 33 ), capable of bearing against said mobile probe ( 32 ), an axially mobile check valve seat ( 34 ), capable of bearing against the check valve ( 33 ), the mobile probe ( 32 ) being controlled by the braking control member ( 1 ) so as to move away from the check valve ( 33 ) and thus put the working chamber ( 41 ) in communication with atmospheric pressure, and said check valve seat ( 34 ) being controlled by the pressure prevailing in the hydraulic braking circuit ( 6 ) to move away from said check valve ( 33 ) and permit said check valve to move toward the mobile probe ( 32 ) and to interrupt the communication of the working chamber ( 41 ) with atmospheric pressure when the pressure in the braking circuit exceeds said pressure threshold.