Abstract: The brake comprises two shoes lined with friction elements stressed by a clamping mechanism located between two first ends of the shoes, a fixed anchoring block located between the other two ends of the shoes, and a spacer (44) mounted in the vicinity of the clamping mechanism and bearing by each of its ends on each of the shoes.

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 two chambers (8, 9) on either side of the movable wall structure forming a piston (7) are each sealingly delimited internally by a first and a second flexible impervious walls (23) which connect the central hub part (11) incorporating the control valve (12) to the central annular end zones (22 ; 24) of the corresponding end walls (2 ; 3) of the housing, the central zones delimited peripherally by said flexible walls being interconnected by at least a passage (39) traversing the central hub part, thus providing in the center of the housing a neutral cylindrical zone (32). In this neutral zone (32) there extend force-transmitting elements (38) which have at their ends fastening means (40), for example with assembly flanges (41, 42), and which slidingly pass through said passages (39) formed in the body of the central hub part (11), thus in no way interfering with the control and fluid actuation system of the servo-motor.

Abstract: The braking pressure corrector is controlled by the load of the vehicle by means of a controlling unit. This controlling unit (20) comprises a push rod (22), a preloading spring (26) exerting a thrust of fixed magnitude on the push rod (22), and a controlling spring (42) exerting on the push rod, through a reversing device (36), a traction of variable magnitude as an inverse function of the load of the vehicle. According to the invention, the reversing device (36) is mounted to pivot with respect to the casing (12,24) of the corrector by means of an articulation (38) of the swivel joint type.

Abstract: A solenoid valve comprising a housing having opposed inlet and outlet ports which communicate via a passage containing a poppet member movable in response to energization of a coil is disclosed. A flexible wall is further provided in said passage to define inlet and outlet chambers communicating respectively with said inlet and outlet ports. A second passage in said flexible wall connects said chambers, and a resilient spring urges a valve seat defined in said second passage into fluid tight engagement with the poppet member, whatever the position of the latter. The poppet member is movable between a first position in which it urges the wall against an abutment, thereby preventing any communication between the inlet and outlet ports, and a second position in which the wall is movable relative thereto, whereby said wall acts as a non-return valve between the inlet and outlet ports.