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 present invention relates to an assembly comrising a bulkhead (10) separating an engine compartment from a passenger compartment of a vehicle and a pneumatic booster (12) assisting the braking of the vehicle and comprising essentially a tube into which an operating rod (16) actuated by a brake pedal situated in the passenger compartment penetrates and a closed casing defining the pneumatic chambers of the booster disposed in the engine compartment. According to the invention the tube (14) is fastened to a collar (18) which has a diameter substantially smaller than that of the opening; the collar (18) is shaped in such a way as to have, at least in part, an end wall (20) parallel to the bulkhead; the collar (18) has a peripheral groove housing a ring (22); the ring (22) has, at least in part, an elastic edge (24) projecting outwards.

Abstract: The invention relates to a pneumatic brake-booster comprising a casing (10) inside which is a piston formed by a hub (20) and by a skirt (14) and which, with the aid of an unrolling membrane (12), defines a front chamber (16) permanently connected to a partial vacuum source and a back chamber (18) connected selectively to the front chamber (16) when a first valve passage (56, 58) is opened or to the atmosphere when a second valve passage (76, 78) is opened, the first and second valve passages (56, 58; 76, 78) being formed by first valve means (58, 78) co-operating with second valve means (56, 76), and being actuated by a control rod (35) capable of bearing, through the intermediary of a plunger (32), against one of the faces of a reaction disk (42) securely attached to a push rod (44).According to the invention, the first valve means (58, 78) are formed on the hub (20) of the piston.

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).

Abstract: The invention relates to a pneumatic brake-booster comprising a casing (10), inside which is situated a piston (20) comprising a rear tubular part (22) and a movable wall (12) defining a front chamber (16) permanently connected to a vacuum source and a rear chamber (18) selectively connected to the front chamber (16) or to the atmosphere by a valve mechanism (20a, 32a, 40) actuated by a control rod (34) adapted to bear, by way of a plunger (32) against one face of a reaction disk (58) fastened to a push rod (56), the valve mechanism comprising a valve closure member (40) cooperating by an active part with a first valve seat (32a) formed on the plunger (32) and with a second valve seat (20a) formed on the piston (20). According to the invention, a guide mechanism (62) for the air in movement are provided upstream of the valve mechanism.

Abstract: The invention relates to a pneumatic brake-booster comprising a casing (10), inside which is situated a piston (22) consisting of a rear tubular part (22) which supports a skirt (14) and which with the aid of an unwinding diaphragm (12) defines a front chamber (16) permanently connected to a vacuum source and a rear chamber (18) selectively connected to the front chamber (16) or to the atmosphere by a valve mechanism (20a, 32a, 40) actuated by a control rod (34) adapted to bear, by way of a plunger (32) sliding in a bore (30) of the piston (20), against one face of a reaction disk (58) fastened to a push rod (56), the valve mechanism (20a, 32a, 40) comprising a valve closure member (40) cooperating with a first valve seat (32a) formed on the plunger (32) and with a second valve seat (20a) formed on the piston (20 ), a retaining member (50), for the plunger (32) disposed in a radial space (38) in the piston (20) and having an inner end region extending the bore (30) of the piston (20) and forming a stop surfac

Abstract: The invention relates to a pneumatic brake-booster comprising a casing (10), inside which is situated a piston (20) consisting of a rear tubular part (22) which supports a skirt (14) and which with the aid of an unwinding diaphragm (12) defines a front chamber (16) permanently connected to a vacuum source and a rear chamber (18) selectively connected to the front chamber (16) or to the atmosphere by a valve mechanism (20a,32a, 40) actuated by a control rod (34) adapted to bear, by way of a plunger (32), against one face of a reaction disk (58) fastened to a push rod (56), the valve mechanism (20a, 32a, 40) comprising a valve closure member (40) cooperating with a first valve seat (32a) formed on the plunger (32) and with a second valve seat (20a) formed on the piston (20). According to the invention, the plunger (32) and the piston ( 20) are provided with a second valve mechanism (65, 70).

Abstract: The invention relates to a pneumatic brakebooster possessing a casing (10), within which is located a piston (22, 14, 102) formed from a rear tubular part (22) supporting a skirt (14) and, with the aid of an unrolling diaphragm (12), defining a front chamber (16) connected permanently to a vacuum source and a rear chamber (18) connected selectively to the front chamber (16) or to the atmosphere by a valve mechanism (136, 138, 140) actuated by a control rod (34) capable of bearing by way of a plunger (32) on one of the faces of a reaction disk (58) fixed to a push rod (56), a return spring (150) for the control rod (34) being arranged between the skirt (14) of the piston and the plunger (32), the valve mechanism (136, 138, 140) possessing a shutter (138) interacting by an active part made rigid by an insert (118) with a first valve seat (136) formed on the plunger (32) and with a second valve seat (140) formed on the piston (14), the shutter (138) being formed by a flexible tubular diaphragm (114), the active

Abstract: The invention relates to a pneumatic brake booster comprising a casing (10), within which is located a piston (22, 14, 102) formed from a rear tubular part (22) supporting a skirt (14) and, by way of an unrolling diaphragm (12), defining a front chamber (16) connected permanently to a vacuum source and a rear chamber (18) connected selectively to the front chamber (16) or to the atmosphere by a valve mechanism (136, 138, 140) actuated by a control rod (34) capable of bearing by way of a plunger (32) on one of the faces of a reaction disk (58) fixed to a push rod (56), the valve mechanism (136, 138, 140) possessing a shutter (138) made rigid by an insert (118) and interacting by an active part with a first valve seat (136) formed on the plunger (32) and with a second valve seat (140) formed on the piston (14), the shutter (138) being formed by a flexible tubular diaphragm (114), the active part of the shutter (138) being located between the two ends (112, 116) of the flexible tubular diaphragm (114), a stop me

Abstract: The invention relates to a pneumatic brake booster comprising a casing (10), within which is located a piston (22, 14, 102) formed from a rear tubular part (22) supporting a skirt and which, by way of an unrolling diaphragm (12), defining a front chamber (16) connected permanently to a vacuum source and a rear chamber (18) connected selectively to the front chamber (16) or to the atmosphere by a valve mechanism (136, 138, 140) actuated by a control rod (34) capable of bearing, by way of the front face (32b) of a plunger (32), on the rear face (58a) of a reaction disk (58) fixed to a push rod (56), a spring (150) for the return of the control rod (34) being arranged between the skirt (14) of the piston and the plunger (32), the valve mechanism (136, 138, 140) comprising a shutter (138) made rigid by an insert (118) and interacting by an active part with a first valve seat (136) formed on the plunger (32) and with a second valve seat (140) formed on the piston (14), the shutter (138) being formed by a flexible

Abstract: The invention relates to a pneumatic brake-booster comprising a casing (10), inside which is situated a movable wall (12, 14) returned to a rear position of rest by a resilient mechanism and defining a front chamber (16) permanently connected to a vacuum source (61) and a rear chamber (18) selectively connected to the front chamber (16) or to the atmosphere by a valve mechanism (20a, 32a, 40) actuated by a control rod (34) adapted to bear, by way of a plunger (32), against one face of a reaction disk (58) fastened to a push rod (56). According to the invention, the resilient mechanism returning the movable wall (12, 14) to its rear position of rest exerts a modulable force on the movable wall (12, 14).

Abstract: The invention relates to a device for measuring the position of a push rod (30) of a pneumatic booster consisting of a housing (10) divided into a front chamber (20) and a rear chamber (22) by way of a moveable wall (18) returned to its rest position by a restoring spring (34), the booster actuating a piston (84) of a master cylinder (86) by means of the push rod (30), the measuring device comprising a first part (40) stationary relative to the housing (10) of the booster and a moveable second part (60), the first part (40) and second part (60) carrying electrical contacts (46, 46', 48, 48', 84; 76, 78).According to the invention, the first part (40) and second part (60) are cylindrical and coaxial, and they are arranged round the push rod.

Abstract: The invention relates to a vacuum brake-booster of the tandem type comprising two compartments (22, 24) separated by a stationary plate (20), each of the compartments being divided into a front chamber and a rear chamber by way of a piston (26, 28) and of an isolating diaphragm, at least the inner edge of which is equipped with a bead (38), each of the pistons (26, 28) being fixed to a movable hub (42) containing a valve mechanism, the piston (26) of the front compartment being so fixed by way of a cylindrical sleeve (30). According to the invention, the hub (42) possesses, on its periphery, a groove (32) into which penetrate respectively the inner end (34) of the piston (28) of the rear compartment (24) and the rear end (26) of the cylindrical sleeve (30), the bead (38) of the inner edge of the diaphragm (40) of the rear compartment (24) ensuring the locking of the assembly as a whole.

Abstract: The actuating device for a master cylinder is constituted by an actating rod (10) acting on a piston (12) of the master cylinder. Elastic centering mechanism (26) are arranged between the actuating rod (10) of the master cylinder and the piston (12) of the master cylinder, and are compressed therebetween.

Abstract: The invention relates to an assembly consisting of a brake booster and of a master cylinder (50), the booster comprising, in a casing (10), at least one movable wall (14, 14') which sealingly divides the interior of the casing (10) into a front chamber (16, 16') and a rear chamber (18, 18'), an input member (24) intended to be connected to a brake pedal and displacing the movable wall (18, 18'), and an output member (28) actuating a piston (46) of the master cylinder (50). According to the invention, a transfer member (40) is arranged between the front face of the casing (10) and the master cylinder (50), this transfer member (40) being actuated by the output member (28) of the booster along a first axis (A--A) and actuating the piston (46) of the master cylinder (50) along a second axis (B--B), and the brake booster, the transfer member (40) and the master cylinder ( 50) form a modular construction.

Abstract: In the booster are mounted movably a hollow booster piston (20) and a control rod (30) carrying a plunger (28) seated in the piston (20), the rear end of the plunger (28) forming a first annular valve seat (28a) concentric with a second annular valve seat (20a) carried by the booster piston (20), the first valve seat (28a) and second valve seat (20a) interacting with an annular shutter (34) carried by the booster piston (20), and a reaction disk (48) being interposed between an annular front face (20b) of the booster piston (20) and a rear face of a push rod (46). The process for adjusting the value of the pump of the booster comprises the following steps:applying to the push rod (46) a force equal to the boost force corresponding to the desired jump of the booster,moving the seat (20a) of the booster piston (20) away from the shutter (34),putting the front face of the plunger (28) and the rear face of the reaction disk (48) into contact and maintaining this contact during the next step.

Abstract: The assembly comprises a brake-booster and a master cylinder having, in an outer casing (10), a space divided in leakproof fashion into a front chamber (12) and a rear chamber (14) by a movable partition (16), at least a first resilient mechanism (18) tending to displace the movable partition towards the rear chamber. The front chamber is connected to a vacuum source, and a pressure difference is established between the front and rear chambers by a valve mechanism (20) capable of connecting the rear chamber to the atmosphere upon actuation of a control rod (22) in order to displace the movable partition towards the front chamber. A master cylinder (30) is fixed on the front wall of the casing and has a bore (40) in which a tappet (42) integral with the movable partition and delimiting an enclosed space (28) in the master cylinder slides in leakproof fashion. This tappet has a bore (32) in which a reaction piston (24) subjected to the pressure of the enclosed space (28) slides in leakproof fashion.

Abstract: The booster comprises, arranged coaxially, a piston 4, a plunger 20 seated in the piston and integral with a control rod 12, a push rod 16, a reaction disc 14 and an assembly of valve shutters interacting with one end of the plunger and with a seat 18 forming part of the piston. The assembly of valve shutters comprises a first shutter 24 coming to bear on the seat 18 and a second shutter 34 accompanying the plunger 20 until its stroke is stopped by a counterstop 58, the axial position of which is adjustable from outside.

Abstract: In the double brake-booster and master cylinder assembly, the booster comprises, in an outer casing 10, a fixed partition 11 defining, inside the casing 10, a front space A and a rear space B, each space A, B being divided in a sealed manner into a front chamber 12, 18 and a rear chamber 14, 20 by a movable partition 16, 22, at least one elastic mechanism 31 tending to displace one 16 of the movable partitions 16, 22 rearward, at least one passage 38 connecting the two front chambers 12, 18, at least one passage 53 connecting the two rear chambers 14, 20, a pressure difference being established between the front 18 and rear 20 chambers of the rear space B by a valve mechanism 35 on actuation of a control rod 27 in order to actuate an output rod, the output rod actuating a piston of the master cylinder.

Abstract: A pneumatic brake-booster comprises a casing on which is formed a well (12) housing operating valve mechanism, a first wall (10) having at least one opening (14) cooperating with a mechanism for fastening the casing on a fixed part of a vehicle, a second wall having at least one opening cooperating with a mechanism for fastening a master cylinder on the casing, at least one annular member (16) being disposed in the casing, against a wall. The fastening mechanism consists of at least one projecting portion (18) of the annular member (16).