Abstract: A master cylinder comprising a body (4) pierced with a bore (5) closed on a first side by an end (6) and on a second side by a piston (7). The piston (7) slides in the bore (5) to delimit a pressure chamber (8). The pressure chamber (8) is connected by a pressure pipe (12) to at least one brake motor through an outlet (11) therein. The chamber (8) and the pressure pipe (12) together delimiting a working volume filled with a hydraulic fluid. The working volume is partially delimited by a leak-off device (19) which is responsive to an impact to selectively allow hydraulic fluid to leak off toward the outside of the working volume.

Abstract: This boosted braking device comprises a pneumatic brake booster (1) associated with a master cylinder (2) and provided with an automatic control solenoid valve (26), this booster operating according to a mixed reaction principle and comprising a movable pneumatic piston (5) carrying a control valve (7) actuated by a rod (8), as well as a partition (4) which can be moved under the effect of a pressure difference, this movable wall (4) being mounted slidingly with respect to the pneumatic piston (5). The device of the invention makes it possible, with very few elements, to provide automatic braking without disturbing the normal operation of the booster.

Abstract: A pneumatic brake booster having a casing (10) with an axis of symmetry (X-X') divided in a leaktight fashion by a movable wall structure (12) into a front chamber (14) permanently connected to a source of low pressure, and a rear chamber (16). The rear chamber (16) is connected selectively to the front chamber (14) or a source of high pressure by a three-way valve means (36). The three-way valve means (36) is actuated by a control rod (30) capable of pressing, via a front face of a plunger (28), on a rear face of a push rod (56) secured to a reaction disc (58) when a plunger (28) slides in a bore (26) of the movable wall (12). The three-way valve (36) includes a valve element (36) located in a tubular rear part (22) of the movable wall (12) and interacts via of an annular front face (40) with a first annular valve seat (28a) formed on the plunger (28) and with a second annular valve seat (20a) formed on the movable wall (12).

Abstract: A pneumatic servo for assisting braking. The servo has a casing with an axis of symmetry which is divided in leaktight fashion by a movable wall structure into a front chamber and a rear chamber. The front chamber is permanently connected to a source of partial vacuum while the rear chamber is connected selectively to the front chamber and to air in the surrounding environment by a three-way valve. A sleeve divided an annular bore located in a projection that extends through the movable wall through the casing into a static volume and a concentric annular volume. The sleeve engages the projection to position the three-way valve in the bore. A return spring located in the static volume engages the control rod while an end plug engages the sleeve to seal the static volume from the surrounding environment. The annular volume being is respectively connected by first and second openings to the surrounding environment and bore.

Abstract: An assembly of a pneumatic brake booster (100) and a master cylinder (200) for a motor vehicle. The pneumatic brake booster (100) has a casing (20) fixed to the bulkhead (10) of the vehicle. The casing is divided in leaktight fashion by a movable wall structure (22) into a front chamber (24) permanently connected to a source of partial vacuum and a rear chamber (26) connected selectively to the front chamber (24) or to the atmosphere by a valve means (16). The valve means (16) is actuated by a control rod (14) for actuating a push rod (28). The master cylinder (200) has a body (21) formed with at least first and second flanges (38, 38'; 40, 40'). The first and second flanges (38, 38'; 40, 40') interact with corresponding screws and nuts to fix the body (21) with the casing (20) of the booster (100). The body (21) has a bore (34) for slidingly receiving at least one piston (32) which is actuated by the push rod (28) of the brake booster (200).

Abstract: A pneumatic brake booster having a casing (10) with a piston located therein. The piston has a hub (22,22') with a tubular part (24,24'), a portion of which extends in a sealed fashion through the casing (10). The hub (22,22') has an annular groove (29) which receives an internal peripherial bead (19) of a rolling seal (18) which holds a skirt (16) against a shoulder. The rolling seal (18) engages the casing (10) to define a front chamber (12) which is permanently connected to a source of depression and a back chamber (14) selectively connected to the front chamber (12) and to atmosphere via valve apparatus (22a,32a,36). The valve apparatus (22a,32a,36) is actuated by a control rod (34) capable of pressing, by way of a front face on a plunger (32), on a first face of reaction disk (40) secured to a second face on a push rod (42). The tubular part (24') of the piston is connected to the hub (22) by clipping.

Abstract: A pneumatic brake-booster having a casing with a piston located therein consisting of a hub and a skirt to define a front chamber and a rear chamber. The front chamber is connected permanently to a vacuum source and the rear chamber is connected selectively through a bore in the hub to one of the front chamber and atmosphere by a control valve. The control valve is actuated by a control rod capable of pressing through a front face of a plunger on a back face of a reaction disk fastened securely to a thrust rod. A return spring for the control rod is located between the piston and the plunger. The control valve includes a shutter valve which interacts with a first circular valve seat formed on the plunger and a second circular valve seat formed on the piston. The shutter valve is characterized by a flexible membrane having a first bead fixed in a leaktight manner to a peripheral edge of the hub and a second bead connected in a leaktight manner to an internal peripheral edge of a rigid tubular component.

Abstract: This device comprises in a manner known per se a valve (7) cooperating with two valve seats (10b, 16a) to control the operation of the booster.The second seat (16a) is formed on a sliding sleeve (16) in such a manner as to accelerate the admission of air and to shorten the response time of the booster.

Abstract: The invention relates to a pedal for a motor vehicle, particularly a brake pedal.The pedal rod (50) is articulated on a pin borne by a yoke securely attached to the end of the control rod (56). According to one embodiment, the yoke and the pedal rod are held against the pin by a resilient system constituted by a spring-forming wire (100) which interacts with the surface (54) of the pedal rod and the ends of which are securely attached to the yoke.

Abstract: A pneumatic brake booster having a piston which slides in a casing with a portion that extends outside of the casing. A tubular protective bellows has a first end connected to the casing and a second end that engages an input rod through which an operational signal is communicated to a valve retained the valve. The bellows is made of a porous and deformable material such that air communicated to the valve in response an input force applied to the control rod is directly passes through the porous bellows. The porous bellows has a pore size such that any contamination in the air is removed or filtered before being presented to the valve.

Abstract: The invention relates to means for adjusting the jump in a pneumatic braking assistance servomotor, said means including a cup (50) encircling the reaction disk (11) and a radial widening (13) integral with the push-rod (12). The adjustment is carried out by partial screwing of the cup in the piston or recoil of the push-rod without initial strain of the reaction disk (11).

Abstract: This brake-booster device comprises a pneumatic brake-booster (1) associated with a master cylinder (2). The booster comprises a movable pneumatic piston (5) bearing a valve (7) and functions according to a hydraulic reaction principle, the hydraulic piston (11) of the master cylinder comprising in fact a hollow movable cylinder (13) receiving a boost force, and a secondary hydraulic piston receiving an input force, these two forces constituting the total actuation force. A helical spring (22), exerting an adjustable resilient force, is disposed between the secondary hydraulic piston and the movable cylinder so as to permit the adjustment of the non-zero minimal value of the actuation force.

Abstract: A brake actuation apparatus includes a pneumatic booster and a master cylinder. A control rod in the booster responds to an input force for actuating a valve in the brake booster to develop an actuation force which is applied to a main hydraulic piston located in the master cylinder to pressurize fluid and effect a brake application. The main hydraulic piston includes a cylinder member with a bore therein for retaining a secondary hydraulic piston connected to the control rod. The cylinder member has at least one opening whereby pressurized fluid is communicated between the master cylinder and bore as function of a flow-rate reducer located in the one opening. The communication of fluid between the master cylinder and bore is always from the higher fluid pressure toward the lower fluid pressure.

Abstract: This boosted brake device comprises a pneumatic brake booster (1) associated with a master cylinder (2), the booster operating according to a hydraulic reaction principle and comprising a movable pneumatic piston (5) carrying a control valve (7) actuated by a rod (8), as well as a partition (4) which can move under the effect of a pressure difference and which develops a boost force.The movable wall (4) is mounted slidingly with respect to the pneumatic piston (5) in order to act early on the master cylinder.The device of the invention allows greater braking for small values of the travel of the control rod.

Abstract: The invention relates to a removable thrust rod in a brake-booster of the partial vacuum type. The thrust rod (24) is attached securely to a skirt-shaped component (42) which surrounds the reaction disk (30) and to a component (44). A detachable component (50) comprises clipping fingers (54) which interact with the periphery of the component (44) and an annular part (52) which is flattened onto the piston (18) of the booster by a return spring (34).

Abstract: A pneumatic brake booster has a thrust rod (13) guided by a sleeve (16) supported by a hydraulic piston (14) of a master cylinder (2). The thrust rod has a thrust washer (15) fixedly attached, which bears against a flat bottom of a cup (12) housing a reaction disc (11). The thrust washer is able to slide relative to the flat bottom.

Abstract: The invention relates to a brake-booster comprising a casing (10) within which is found a piston structure which, with the help of an unrolling membrane (12), defines a front chamber (16) permanently connected to a partial vacuum source by a valve (17) and a back chamber (16) selectively connected to the front chamber (16) or to the atmosphere via a valve means (34) when a control rod (30) is actuated, and a device (36) for fastening the booster on a wall (38) adjacent to a first face of the casing (10). According to the invention, apertures (50, 60) are made in the piston structure (14) and in a second face of the casing (10) and are aligned in the axial direction of the booster so as to permit the actuation of the fastening device (36) through the aperture (60) made in the second face of the casing (10).