A hydraulic brake assembly (12) includes a housing (24) having first and second side-by-side bores (30), each defining a respective master cylinder assembly. Each master cylinder assembly includes a master cylinder piston (32) slidably movable by actuation of a respective brake pedal (18a, 18b) to and between an active position and an inactive position. A spool (74) slidably disposed within a piston bore (70) of the master cylinder piston (32) is operable in a first mode to direct hydraulic fluid from a quick-fill chamber (62) to a master cylinder chamber (50) at a first pressure upon initial movement of the master cylinder piston (32) from the inactive position toward the active position. The spool (74) is operable in a second mode to direct hydraulic fluid from the quick-fill chamber (62) to a tank (20) when pressure in the master cylinder chamber (50) reaches a predefined threshold.

A braking circuit including at least an auxiliary right valve (200) and an auxiliary left valve (300) suitable to allow braking on both sides, right and left of a vehicle, when this is required, but allowing to apply a pressure braking only on one of the two sides, right or left, when this is required to provide a steering function, characterized in that the circuit further comprises a master valve (400) having two positions: a first position when the vehicle has a velocity under a threshold wherein separate and selective right or left braking is authorized and a second position when the vehicle has a velocity above said threshold wherein said master valve (400) connects both a right braking line (204, 1205) and a left braking line (304, 1305) to an output braking line (110) so that if a braking is requested both right braking line (204, 1204) and left braking line (304, 1305) are under pressure and selective right or left braking is forbidden.

A braking circuit including at least an auxiliary right valve (200) and an auxiliary left valve (300) suitable to allow braking on both sides, right and left of a vehicle, when this is required, but allowing to apply a pressure braking only on one of the two sides, right or left, when this is required to provide a steering function, characterized in that the circuit further comprises a master valve (400) having two positions: a first position when the vehicle has a velocity under a threshold wherein separate and selective right or left braking is authorized and a second position when the vehicle has a velocity above said threshold wherein said master valve (400) connects both a right braking line (204, 1205) and a left braking line (304, 1305) to an output braking line (110) so that if a braking is requested both right braking line (204, 1204) and left braking line (304, 1305) are under pressure and selective right or left braking is forbidden.

A master cylinder includes: a cylinder housing; a piston which is movably disposed in the cylinder housing so as to form a pressure chamber and a hydraulic fluid supplying chamber; a sealing member which is interposed between the cylinder housing and the piston. The piston has a plurality of communication holes for connecting the pressure chamber and the hydraulic fluid supplying chamber, and the plurality of communication holes are formed on a slanted surface which is provided to an outer surface of the piston.

A master cylinder includes: a cylinder housing; a piston which is movably disposed in the cylinder housing so as to form a pressure chamber and a hydraulic fluid supplying chamber; a sealing member which is interposed between the cylinder housing and the piston. The piston has a plurality of communication holes for connecting the pressure chamber and the hydraulic fluid supplying chamber, and the plurality of communication holes are formed on a slanted surface which is provided to an outer surface of the piston.

A brake apparatus improved in mountability on a vehicle is provided. The apparatus includes a master cylinder 4 that generates hydraulic brake pressure by a driver's brake operation, and a stroke simulator 5 that creates an artificial operation reaction force of a brake operation member when the brake fluid flown out of the master cylinder 4 enters the stroke simulator 5. The master cylinder 4 and the stroke simulator 5 are integrally arranged to overlap each other in a perpendicular direction (as viewed from the perpendicular direction) when installed in the vehicle.

A brake apparatus improved in mountability on a vehicle is provided. The apparatus includes a master cylinder 4 that generates hydraulic brake pressure by a driver's brake operation, and a stroke simulator 5 that creates an artificial operation reaction force of a brake operation member when the brake fluid flown out of the master cylinder 4 enters the stroke simulator 5. The master cylinder 4 and the stroke simulator 5 are integrally arranged to overlap each other in a perpendicular direction (as viewed from the perpendicular direction) when installed in the vehicle.

A master cylinder for a hydraulic brake comprises a compensating chamber, a cylinder in which a piston is movably disposed, a pressure chamber disposed in the cylinder and connected to the compensating chamber through at least one connecting opening, and a gasket for interrupting the connection between the pressure chamber and the compensating chamber. The gasket seals the compensating chamber and the pressure chamber against the environment.

A master cylinder for a hydraulic brake comprises a compensating chamber, a cylinder in which a piston is movably disposed, a pressure chamber disposed in the cylinder and connected to the compensating chamber through at least one connecting opening, and a gasket for interrupting the connection between the pressure chamber and the compensating chamber. The gasket seals the compensating chamber and the pressure chamber against the environment.

A braking circuit including at least an auxiliary right valve (200) and an auxiliary left valve (300) suitable to allow braking on both sides, right and left of a vehicle, when this is required, but allowing to apply a pressure braking only on one of the two sides, right or left, when this is required to provide a steering function, characterized in that the circuit further comprises a master valve (400) having two positions: a first position when the vehicle has a velocity under a threshold wherein separate and selective right or left braking is authorized and a second position when the vehicle has a velocity above said threshold wherein said master valve (400) connects both a right braking line (204, 1205) and a left braking line (304, 1305) to an output braking line (110) so that if a braking is requested both right braking line (204, 1204) and left braking line (304, 1305) are under pressure and selective right or left braking is forbidden.