HYDRAULIC POWER BRAKE APPARATUS

HYDRAULIC POWER BRAKE APPARATUS The hydraulic power braking apparatus comprises a fluid power apparatus (10) receiving fluid pressure from a power steering apparatus of the vehicle, the fluid power apparatus (10) connected at one end to the brake pedal of the vehicle and at the other end to a master cylinder (110). The master cylinder (110) is connected to a fluid displacement multiplier (210), fluid pressure developed by the master cylinder being communicated to the fluid displacement multiplier (210). The fluid displacement multiplier (210) comprises a housing (212) having therein a stepped chamber (211) with a differential area piston (213), the differential area piston (213) having a through passage (240) controlled by a poppet valve (250). A fluid pressure line (31) communicates the working chamber (18) of the fluid power apparatus (10) with a variable volume chamber (290) of the displacement multiplier (210) so that when actuation of the brake system causes operation of the fluid power apparatus (10), fluid pressure in the working chamber (18) is communicated directly to the displacement multiplier (210) in order to provide an additional fluid power boost to the differential area piston (213) activated by output fluid pressure received from the master cylinder (110).