Abstract: A master cylinder is described. The master cylinder includes a chamber delimited by a piston and supplied from a brake fluid reservoir installed on the top of the master cylinder by an end fitting engaged in a nozzle on the body of the master cylinder. The piston has a nose of reduced section upstream of its skirt guided in the bore hole of the master cylinder and the nozzle is connected to the chamber by a drill hole issuing into the chamber at least partly upstream of the piston in rest position. A valve module is installed in the drill hole to manage communication between the reservoir and the chamber as a function of the position of the piston and the pressure in the chamber with respect to the pressure in the reservoir.

Abstract: A master cylinder is described. The master cylinder includes a chamber delimited by a piston and supplied from a brake fluid reservoir installed on the top of the master cylinder by an end fitting engaged in a nozzle on the body of the master cylinder. The piston has a nose of reduced section upstream of its skirt guided in the bore hole of the master cylinder and the nozzle is connected to the chamber by a drill hole issuing into the chamber at least partly upstream of the piston in rest position. A valve module is installed in the drill hole to manage communication between the reservoir and the chamber as a function of the position of the piston and the pressure in the chamber with respect to the pressure in the reservoir.

Abstract: The invention relates to a brake booster with a short actuating travel, in which booster the three-way valve has a moving valve seat borne by a sleeve (54). The movement of this sleeve is controlled by the piston. The invention provides a device that comprises a face (100) that is inclined with respect to the axis of the sleeve in order to allow the sleeve (54) to move gradually.

Abstract: The invention relates to a tandem pneumatic brake booster (1) for a vehicle. The objective is to prevent a blocking of a booster thrust rod (4) in the maximum travel position. The blocking appears following a sealed adhesion of a first plate skirt (12) on a seal (22) of the tandem booster. This seal blocks a vacuum in a first front chamber (5). To prevent this blocking, provision is made to crenelate a first lip (23) pressed against the pneumatic piston (3) of a seal. Merlons prevent a sealed adhesion of the plate skirt (12) over the whole seal (22). This absence of adhesion creates a leakage of air to the first front chamber (5) and allows a return to a rest position.

Abstract: The invention relates to a brake booster with a short actuating travel, in which booster the three-way valve has a moving valve seat borne by a sleeve (54). The movement of this sleeve is controlled by the piston. The invention provides a device that comprises a face (100) that is inclined with respect to the axis of the sleeve in order to allow the sleeve (54) to move gradually.

Abstract: The invention relates to a tandem pneumatic brake booster (1) for a vehicle. The objective is to prevent a blocking of a booster thrust rod (4) in the maximum travel position. The blocking appears following a sealed adhesion of a first plate skirt (12) on a seal (22) of the tandem booster. This seal blocks a vacuum in a first front chamber (5). To prevent this blocking, provision is made to crenelate a first lip (23) pressed against the pneumatic piston (3) of a seal. Merlons prevent a sealed adhesion of the plate skirt (12) over the whole seal (22). This absence of adhesion creates a leakage of air to the first front chamber (5) and allows a return to a rest position.

Abstract: A tie rod (40) for mounting a booster and the brake control master cylinder on a bulkhead (3) of the vehicle engine compartment. The tie rod (4) comprises, at each of its ends, a shoulder (43, 44) defining a bearing surface having a frustoconical shape. Each shoulder is situated in such a way that a narrow part of its frustoconical surface is near a threaded part (41, 42) used to secure the booster and is located inside of the booster in such a way that each frustoconical surface is in contact with a corresponding frustoconical hole (81, 82) in a wall of the booster.

Abstract: A tie rod (40) for mounting a booster and the brake control master cylinder on a bulkhead (3) of the vehicle engine compartment. The tie rod (4) comprises, at each of its ends, a shoulder (43, 44) defining a bearing surface having a frustoconical shape. Each shoulder is situated in such a way that a narrow part of its frustoconical surface is near a threaded part (41, 42) used to secure the booster and is located inside of the booster in such a way that each frustoconical surface is in contact with a corresponding frustoconical hole (81, 82) in a wall of the booster.

Abstract: A braking amplifier for a vehicle having a vacuum chamber (10), a working chamber (12) separated by a housing (14), a shutter (30) and an intermediate chamber (64). The intermediate chamber (64) is located in the housing (14) and defined by a plurality of circular zones (44) arranged around and axis (6) of the amplifier that are in communication with the vacuum chamber (10). The end of the circular zones (4) have a rear section (50) that form a seat (52) for the shutter (30). The shutter (30) selectively engaging seat (52) to interrupt communication between the vacuum chamber (10) and the intermediate chamber (64) and thereafter place the intermediate chamber (64) in communication with the working chamber (12) to effect a brake application.

Abstract: Braking device including a master cylinder (2), a primary piston (3), a control member (4), a booster (6) coupled to the control member (4), and an assist valve (VA) defined by a reaction piston (17) with a bore (18) therein for receiving a ratio control member (24). The control member (24) has a piston (29) with a head (25) located in a chamber (26) between the reaction piston (17) and a bushing (27) retained in the bore (18). The bushing (27) has an axial passage (28) that receives a head (25) of piston (29) to form a valve (36) for closing an inlet to a passage (30) in the piston (29). The bushing (27) slides within bore (18) to limit a pressure difference between the chamber (26) and a front part (18a) of the bore (18) to a value below a pressure difference that causes the valve (36) to open.

Abstract: A pneumatic brake booster comprising an envelope of longitudinal axis formed of a dish having a rim and a lid. The envelope defines an interior volume that is divided into a variable-pressure work chamber and a low-pressure chamber by a skirt. The skirt is mounted to sealingly slide along the longitudinal axis of the envelope. The skirt has a central orifice with a pneumatic piston sealingly mounted therein. The sealing between the variable-pressure work chamber and the low-pressure chamber is achieved by a first sealing member arranged between a radially internal first end of the skid and a radially external end of the piston and a second sealing member arranged at a radially external second end of the skid and an internal surface of the rim. The skid provides sealing between the radially external first end of the skirt and the radially internal second end of the skirt.

Abstract: The present invention mainly relates to an improved-safety braking device, intended for reducing the injury risks concerning the driver, owing to the brake pedal if a collision happens, in particular a front impact and, more particularly, the invention deals with an electrohydraulic braking device having a variable hydraulic reaction. A braking device according to the present invention comprises a master cylinder (1) fitted with a pedal-feeling simulation cartridge (3), said master cylinder (1) being actuated by an actuating rod (11) connected to a brake pedal (12), said cartridge (3) comprising a resilient means (29) and compression means (38) for the resilient means (29). These compression means (38) can be actuated by a computer (81) on the detection of an injury risk concerning the driver's legs, so as to reduce the compression rate of the resilient means (29).

Abstract: A pneumatic brake booster comprising a rigid casing (10) locally shaped into a hollow shaft (3), a hub (5) slideably mounted in an opening (30) of the hollow shaft (3), an annular seal (6) inserted between the hub (5) and the hollow shaft (3), and members designed to set the hub (5) in a rest position with respect to the hollow shaft (3). The seal (6) comprises an elastomeric material (61) shaped into an annulus and an annular metal insert (62), the position-setting members (71, 72) being partially formed by the insert (62).

Abstract: The present invention mainly relates to an improved-safety braking device, intended for reducing the injury risks concerning the driver, owing to the brake pedal if a collision happens, in particular a front impact and, more particularly, the invention deals with an electrohydraulic braking device having a variable hydraulic reaction. A braking device according to the present invention comprises a master cylinder (1) fitted with a pedal-feeling simulation cartridge (3), said master cylinder (1) being actuated by an actuating rod (11) connected to a brake pedal (12), said cartridge (3) comprising a resilient means (29) and compression means (38) for the resilient means (29). These compression means (38) can be actuated by a computer (81) on the detection of an injury risk concerning the driver's legs, so as to reduce the compression rate of the resilient means (29).

Abstract: A braking amplifier for a vehicle, comprising: a depression chamber (10); a working chamber (12); a shutter (30); and an intermediate chamber (64) communicating with the depression chamber (10) and forming a seat (52) for the shutter such that the shutter is able to place the intermediate chamber in communication with the working chamber and to prevent this communication. The seat (52) is formed by several separate zones arranged around an axis (6) of the amplifier.

Abstract: Braking device comprising a master cylinder (2), a primary piston (3), a manual-control member (4), a booster (6) coupled to the manual-control member (4), and an emergency assist valve (VA) comprising a reaction piston (17) through which there passes a ratio control (24) having a head (25) located in a chamber (26) lying between the reaction piston (17) and a bushing (27) housed further forward in a bore (18) of the primary piston, this bushing (27) having an axial passage (28) in which there can slide a rapid piston (29), the rear end of which forms, with the head (25), a valve (36) capable of closing the inlet to a passage (30) in the rapid piston. The device comprises a means (E), consisting in the bushing (27) being mounted so that it can slide, for limiting the pressure difference between the chamber (26) and a zone (18a) of the bore situated forward of the bushing, to a value below the one which can cause the valve (36) to open.

Abstract: A braking device comprising a master cylinder (2), a primary piston (3), a manual control member (4), a booster (6) coupled to the manual control member (4) and an emergency assist valve (VA). The emergency assist valve comprising a reaction piston (17) through which there passes a ratio control (T) having a head (26a) situated in a chamber (35) lying between the reaction piston (17) and a bushing (36) located further forward in a bore (18) in the primary piston. The bushing (36) has a bore (37) in which there can slide a rapid piston (38), the rear end (45) of which forms, with the head (26a) of the ratio control, a valve (C). The valve (C) is capable of closing the inlet to a passage (39) in the rapid piston against the action of a spring (41). The braking device comprises a means (26, 27, 30) for preventing a sharp retreat of the reaction piston (17) when the manual control member (4) is released after slow braking.

Abstract: A pneumatic brake booster comprising a rigid casing (10) locally shaped into a hollow shaft (3), a hub (5) slideably mounted in an opening (30) of the hollow shaft (3), an annular seal (6) inserted between the hub (5) and the hollow shaft (3), and members designed to set the hub (5) in a rest position with respect to the hollow shaft (3). The seal (6) comprises an elastomeric material (61) shaped into an annulus and an annular metal insert (62), the position-setting members (71, 72) being partially formed by the insert (62).

Abstract: A pneumatic brake booster comprising an envelope (101) of longitudinal axis (Y) formed of a dish (105) having a rim (153) and a lid (103). The envelop (101) defining an interior volume (107) that is divided into a variable-pressure work chamber (109) and a low-pressure chamber (111) by a skirt (113). The skirt (113) is mounted to sealingly slide along the longitudinal axis (Y) of the envelope (107). The skirt (113) has a central orifice (115) with a pneumatic piston (117) sealingly mounted therein. A three-way valve (123) is mounted in the pneumatic piston (117) and is actuated by an actuating rod (125) connected to a brake pedal.

Abstract: Braking device comprising a master cylinder (2), a primary piston (3), a manual control member (4), a booster (6) coupled to the manual control member (4) and an emergency assist valve (VA) comprising a reaction piston (17) through which there passes a ratio control (T) having a head (26a) situated in a chamber (35) lying between the reaction piston (17) and a bushing (36) located further forward in a bore (18) in the primary piston, this bushing (36) having a bore (37) in which there can slide a rapid piston (38), the rear end (45) of which forms, with the head (26a) of the ratio control, a valve (C) capable of closing the inlet to a passage (39) in the rapid piston against the action of a spring (41). The device comprises a means (26, 27, 30) for preventing a sharp retreat of the reaction piston (17) when the manual control member (4) is released after slow braking.