Abstract: A method and device for adjusting the dead travel of a booster (12) and master cylinder (30) assembly by adjusting the length of a push rod (26) connecting the piston (20) of the booster to a piston (28) of the master cylinder. The length of the push rod (26) being adjusted by plastic deformation in axial compression.

Abstract: A plunger arrangement (46,56,58) for a braking servomotor that has an actuating piston to provide a force to activate a master cylinder. The plunger arrangement (46,56,58) is located in a bore of a movable wall (14) that separates the interior of the servomotor into a front chamber and rear chamber, The plunger arrangement (46,56,58) is connected to a resiliently returned control rod (38) and slides in bore as a function of an input force to define a braking application. The end of the plunger arrangement (46,56,58) is slidingly fitted so as to bias a reaction disk of the actuating rod and transmit a reaction force to the control rod. The plunger arrangement (46,56,58) includes a unidirectional clutch device (56) comprising a key (60) and a sleeve (58) that are slidably mounted on a plunger (46) such that when the control rod (38) is actuated at a given speed the sleeve (58) is locked in the bore of the movable wall (14), independently of the control rod (38), to maintain a braking application.

Abstract: A pneumatic servomotor for an assisted braking of a motor vehicle having a unidirectional clutch device (56). The clutch device (56) has a coaxial sleeve (58) that slides on a plunger (46), and a substantially ring-shaped key (60) that is arranged with a given clearance around the sleeve (58) and driven by a moving piston (22). When an input force is applied at a determined speed onto a control rod (38) that is integral with the plunger (46), the key (60) rocks and locks a finger (52) that biases the piston (22) with respect to the sleeve (58) in an axial position. The key (60) includes a peg (78) for axial indexing of the locking position of the sleeve (58).

Abstract: A braking servomotor (10) having a rigid casing (12) with a movable wall (14) location therein to define a front chamber (16) and a rear chamber (18). The movable wall (14) carries a piston (22) that slidably receives an actuating rod (28) for a master cylinder (36). A control rod (28) is sliding located in a bore inside a piston (22) and moved as a function of an input force. The control rod (28) has an end that bears against a plunger (46) that has a finger (52) that biases a reaction disk (32) located at the rear surface of the actuating rod (28) to transmit a reaction force from the actuating rod through the plunger to the control rod. The servomotor (10) is characterised by a unidirectional clutch device (56) that responds to a predetermined speed at which an input force is applied to the control rod (28) to lock the actuating rod in relation to the piston (22), independently, of the reaction disk (32), the plunger (22) and the control rod (28).

Abstract: A master cylinder having a body (1) pierced with a bore (100) that is partially closed by a guide ring (11). A piston (3) mounted to slide in the guide ring (11) and bore (100) to define a pressure chamber (4) within the bore (100). An inlet (2) having a filling duct (21) which connects the bore (100) with a source of hydraulic fluid having a low pressure when the piston (3) is in a position of rest. The filling duct (21) is located between a flared portion (104) of the bore (100) and a front edge (62) of a ring (6) which slides in the body (1) between the guide ring (11) and pressure chamber (4). The piston (3) and sliding ring (6) have respective a first stop (31) and a second stop (61) which allows the piston (3) to drive the sliding ring (6) along when the piston returns to a position of rest.

Abstract: The invention relates to a master cylinder with hydraulic reaction, comprising a working chamber (12) in which there slides, under the action of a pushrod (50), a hollow main piston (13) inside which a reaction piston (14), itself moved by a plunger (80), delimits a reaction chamber (15) which communicates with the working chamber (12), a prestressed spring (16) offering resistance to a movement of the reaction piston (14) in the opposite direction (X+X−) from its actuating direction (X−X+). According to the invention, a sliding ring (18) is arranged opposite the plunger (80) so that actuation of the reaction piston (14) by the plunger (80) is also accompanied by compression of the spring (16).

Abstract: A master cylinder with hydraulic reaction. The master cylinder having a housing with a working chamber (12) therein in which slides a hollow main piston (3). The main piston (3) has a bore (130) for retaining a reaction piston (14) to define a reaction chamber (15). The reaction chamber (15) is connected to the working chamber (12) through a non-return valve (22) and a restriction (17). The non-return valve (22) and restriction (17) are mounted to independently move with respect to the main piston (3) to avoid a defect with a rise in pressure in the reaction chamber (15) when brake fluid retained in the working chamber has an excessively high viscosity.

Abstract: A master cylinder with a main piston (12) located in a main bore (110) of a body (11). A reaction arrangement including a reaction piston (3) which slides in a secondary bore (120) in the main piston (12) for providing a reaction to a pneumatic booster. The reaction arrangement includes a shut-off seat (31) associated with the reaction piston (3), an annular wall (4) located in the secondary bore (120) at a distance from the reaction piston (3), a ratio change-piston (5) located in a leaktight sliding in a central passage of the annular wall (4) and a floating piston (6) mounted in a leaktight sliding within the ratio change piston (5) for providing the reaction piston (3) with a reaction force when an actuation force is applied to quickly to the reaction piston (3).

Abstract: A master cylinder and pneumatic brake booster having hydraulic reaction means. The hydraulic reaction means which is mounted to slide within a main piston (12) in the master cylinder includes a central shut-off piston (4), a stepped and hollow reaction piston (5) and a ratio-change piston (6). First (71), second (72) and third (73) springs are associated with said hydraulic reaction means such that a push rod (3) receives only a portion of a reaction force is an actuation force is applied rapidly which is proportional to a difference between an internal cross section of the reaction piston (5) and an external cross section of the reaction piston (5).

Abstract: A tandem hydraulic master cylinder having body (1) pierced with a bore having first (2a) and second (2b) inlets for receiving hydraulic fluid at low pressure. A primary piston (3) and a secondary piston (4) respectively slide in first (S1) and second (S2) length sections of the bore of body (1). A primary pressure chamber (5) is located in the bore between the primary piston (3) and the secondary piston (4) and a secondary chamber (6) is located between the secondary piston a bottom of the bore. First and second upstream and downstream sealing cups (91a,91b) and 92a,92b) respective seal the bore and the primary chamber (5) and the secondary chamber (6). The primary chamber (5) has a first re-supply duct (21) and a first outlet orifice (41) and the secondary chamber (6) has a second re-supply duct (22) and a second outlet orifice (42) for receiving and communicating hydraulic fluid.

Abstract: A disc brake having a caliper (1) which straddles a brake disc (D) and a carrier (2) which is fixed to a vehicle. A cylinder (3) is secured to the caliper and closed by a piston 31. Guides (21a,21b,22a,22b) allow the caliper to slide with respect to the carrier (2) in response to an input to bring first (41) and second (42) friction pads into engagement with the brake disc (D) to effect a brake application. At least one of the first (41) and second (42) friction pads has ears (41a,42a) inserted in corresponding housings in the carrier (2). The housing constitutes guides for each ear which engage a lateral star-shaped spring (52a). The star-shaped spring (52a) provides a recoil which moves the first (41) and second (42) pads away from the brake disc (D) after each braking application.