Abstract: Hydraulic assistance device for brake actuation comprising a body (10) having a bore (12) in which first and second piston mechanisms (34, 56) are slidably mounted, the first piston mechanism (34) being displaceable under the effect of the actuation of a third piston (16) mounted slideably in the bore (12), and the second piston mechanism (56) being displaceable by way of a hydrostatic connection formed in a presure chamber (60) defined between the first and the second piston mechanism (34, 56), there being associated with each piston mechanism (34, 56) a respective valve mechanism (52, 78) in a respective hydraulic circuit between a fluid source under pressure (54, 84) and a respective brake circuit (62,88), and a third chamber (30) defined in the bore (12) between the first piston mechanism (34) and the third piston (16), characterized in that the third chamber (30) is partially delimited by a fourth piston (92) which is displaceable under the effect of the pressure in the third chamber (30) as it meets a f

Abstract: The hydraulic assistance device incorporates a casing (10) enclosing first and second sliding components (18, 20) arranged in line, the first component (18) being capable of being displaced under the effect of the displacement of a pushrod (34) and the second component being capable of being displaced through the intermediary of a hydrostatic connection, and associated with each component (18, 20) is a valve mechanism (36, 46) in a respective hydraulic circuit between a source of fluid under pressure and a respective braking circuit (I, II), characterized in that the first and second components (18, 20) each constitute a piston sliding in a bore (14) in the casing (10) and each encloses a valve assembly (26, 40; 36, 46) each controlled by a plunger (30, 44), the plunger (30) of the first valve assembly (26, 36) being actuated by the pushrod (34), and the plunger (44) of the second valve assembly (40, 46) being actuated by the hydrostatic connection between the two pistons (18, 20).

Abstract: Hydraulic assistance device, comprising a body (10) comprising a bore (12) in which a first piston mechanism and a second piston mechanism (18, 20) are slideably mounted, the first piston mechanism (18) being movable under the effect of the actuation of a third piston (16) slidably mounted in the body (10), and the second piston mechanism (20) being movable by the intermediary of a hydrostatic connection formed in a pressure chamber (22) defined between the first and the second piston mechanism (18, 20), a respective valve mechanism (60, 100) being associated with each piston mechanism (18, 20) in a respective hydraulic circuit between a source of fluid under pressure (52, 96) and a respective braking circuit (74, 110); and a third chamber (36) defined in the bore (12) between the first piston mechanism (18) and the third piston (16), the third chamber (36) being connected to a low pressure reservoir (25) through a passage in which a valve mechanism (42 ) is mounted, characterized in that the device incorpora

Abstract: The inertial brake corrector comprises a body (1) closed by a cover (7), with a stepped piston (10) incorporating a tubular extension part (13) extending in a direction opposite the outlet chamber (20) and interacting on the inside by sliding in a leak-proof manner with a central projection of reduced diameter (14) of the cover (7), which extends in the body and which delimits, together with the tubular extension part of the piston, an inlet chamber (21) in which is located an inertial shut-off member (24), of which the retention and guide structure forming a slope (27") is advantageously fixed to the stepped piston (10).

Abstract: The brake comprises a torque control valve comprising a main piston which cooperates via a bearing piece with a shoe of which the bearing force is representative of the torque supplied by the brake during operation of the brake motor. The main piston controls the pressure admitted to the brake motor by a cut-off valve responsive to displacement of the main piston and by a variable volume decompression chamber of which a movable wall decompresses the fluid contained in the brake motor when the torque generated by the brake exceeds the limit of a predetermined torque-pressure law.

Abstract: The correcting valve comprises two identical parallel pistons which control the opening or closing of two valves which are disposed between two inputs and two outputs of two braking circuits. Two thrust members which are subjected to a control pressure urge the pistons in the direction for opening the valves. Two reaction springs co-operate with two transmission members for urging the thrust members in the opposite direction. When the two brakes circuits are supplied, the correcting valve has an identical cut-off pressure for the two circuits. In the event of failure of one of the circuits, the transmission members come into mutual engagement, resulting in a doubling in the cut-off pressure in the circuit which is still intact. The invention is used for dual-circuit braking systems for motor vehicles.

Abstract: The corrector comprises two identical parallel pistons which control the opening and closing of two valves located between two inlets and two outlets of two braking circuits. Two push rods subjected to a control pressure urge the pistons in the direction for opening the valves. A reaction spring cooperates with a transmission element to urge the push rods in the opposite direction. When both braking circuits are being supplied, the corrector presents an identical cut-off point for the two circuits. In the event of one of the circuits failing, the transmission element undergoes tilting which results in an unequal sharing of the reaction force and an increase in the cut-off point in the undamaged circuit.

Abstract: A wheel cylinder includes a housing defining a bore. A piston is reciprocably received in the bore and cooperates with the housing to define a pressure chamber. The wheel cylinder comprises a passage for supplying pressurized fluid to the pressure chamber from a fluid pressure source. The supply passage includes a first portion defined by an annular groove on the piston and a blind axial bore in the piston which communicates with both the annular groove and with the pressure chamber. A valve apparatus is received in the blind bore and modulates the fluid pressure supplied to the pressure chamber as a function of the fluid pressure provided by the pressure source.