Abstract: The invention relates to a pneumatic booster operated by a plunger (9) housed in a bore (61) and carrying a moving seat (102) intended to interact selectively with a shut-off member (111), this member being itself capable of interacting selectively with a fixed seat (101).According to the invention, the plunger (9) comprises a cylindrical body (91) and a collar (92) sliding between a front stop (911) and a rear stop (912) of the body, an anterior section (921) of the collar (92) being engaged between the cylindrical body (91) and the bore (61), a posterior section (922) of the collar (92) carrying the moving seat (102), and it being possible furthermore for the collar (92) to be held temporarily stationary in the bore independently of the movement of the body (91), by means of a channel (14) and of a snap ring (13), in order to allow extended operation of the booster after a sharp braking action.

Abstract: A pneumatic brake booster having a valve (7) actuated by movement of an operating rod (8) within a hub (6) from a position of rest to an extreme actuation position. In the position of rest, the valve (7) is closed to a pressure source (A) and when moved toward the extreme actuation opened to the pressure source (A). A purification filter (9) located between the pressure source (A) and valve (7) is made of a compressible material which has a minimum volume with the valve in the rest position and a maximum volume when the operating rod (8) reaches the extreme actuation position.

Abstract: A pedal arrangement for a motor vehicle having a bulkhead (10) which forms a barrier between an engine compartment (C) and a passenger compartment (H) for a driver and passengers. The pedal arrangement includes a transverse brace (32) which is rigid in bending, a mount (12) for a pedal (14) which is secured to the bulkhead (10) on the passenger compartment (H) side of the bulkhead (10) and at least one rigid force-transmission element (30). The pedal (14) has a lever (16) with a first end articulated to the pedal mount (12) and a second end with an operating shoe (18) attached thereto. The force-transmission element (30) has a first end (28) articulated to the transverse brace (32) and a second end (34) which extends between the pedal mount (12 and lever (16).

Abstract: A master cylinder having a main piston (12) located in a main bore (110) of a body (11) to define a working chamber (13), a reaction piston (3) located in a stepped bore (120) of the main piston (12) to define a reaction chamber (4) with components to providing a hydraulic reaction to a pneumatic booster. The main piston (12) slides in the main bore (110) in response to a boost force to develop an actuation force while the reaction piston (3) slides in the stepped bore (120) in response as a function of the actuation force. A first shut-off seat (41) is located on a front face of the reaction piston (3) is located in the reaction chamber (4) while a second shut-off seat (42) located in the reaction chamber (4) is mounted on a seat support (7) carried by the main piston (12). A first spring (51) urges the reaction piston (3) in a direction most likely to move the first shut-off seat (41) away from the second shut-off seat (42).

Abstract: A brake-control device having a vacuum booster (1), a master cylinder (2) and an electro-hydraulic module (3) for controlling brake pressure. The booster (1) has a front shell (10) and a rear shell (11) having a cylindro-frustroconcal shape with first (R10) and second (R11) outsider radii. The master cylinder (2) and module (3) being secured to the front shell (10) at least three fixing points (71, 72, 73). The fixing points defining a peripheral ring (100) on the front shell which is delimited by an inside radius (Ri) that is equal to half of the outside radius (R10) of the front shell (10).

Abstract: A brake device having a master cylinder (1) connected to a pneumatic booster (2). The pneumatic booster (2) having a rigid casing (3) in which a partition (4) moves to delimit a front chamber (5) from a rear chamber (6). The casing (3) has a front shell (31) which is secured to the master cylinder (1) to form a first wall for the front chamber (5) and a rear shell (32) which forms a second wall for the rear chamber (32). In order to increase the absorption of kinetic energy in the event of an impact force being applied to the front shell (31), the front shell (31) has a peripheral member (311) secured to the rear shell (32) and a central member (312) secured to the master cylinder (1). The peripheral member (311) has a larger relative diameter (D1) than the diameter (D2) for the central member (312).