摘要:
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).
摘要:
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. The primary (3) and secondary (4) are guided by the wall (100) of the bore while the body (1) has a first longitudinal passage (51) connecting the first downstream cup (91b) the second upstream cup (92a) and the first outlet orifice (41) with the primary chamber (5) via a first radial passage (61) situated between the first and second length sections (S1,S2).
摘要:
A hydraulic control device comprises a valve (4) which can be moved inside a casing (1) and a stop for opening the valve at one point, the position of which may be set. The stop (6) slides in an axial housing (7) under the effect of a spring (8) and a stop screw (9). The opening position of the valve (4) may be easily set from outside the casing (1).
摘要:
A device (100) for assembling a pneumatic booster (200). A cover (203) of the booster is housed in a support (101). A cylindrical cap (104) whose internal volume (107) is greater than a volume of a cylinder (206) of the booster, covers the cylinder placed on the cover. A gearing element (110) of the device rotates two sets of rollers (109A and 109B) about the booster. An eccentric (118) controlled by the gearing element allows an oscillating movement of the rollers against a wall of the booster. The swaging is achieved by alternately applying the rollers (109A) and (109B). An angle of attack (114A) of the first rollers is greater than an angle of attack (114B) of the second rollers. The invention also relates to a method of swaging a booster and such a booster.
摘要:
Pneumatic brake booster, in particular for a motor vehicle, comprising a reaction disk (30) interposed between a plunger (28) carried by a control rod actuated by the brake pedal and a thrust rod (32) acting on the primary piston of a tandem master cylinder, the reaction disk (30) being housed inside an annular metal part (36) which cooperates with a stop (50) of the thrust rod (32) by the intermediary of thermal expansion element (48) designed to compensate for the thermal expansion of the reaction disk (30) and its effect on a point of change of assistance ratio.
摘要:
A pneumatic brake booster with reduced dead travel comprising a skirt (10) which can move in a sealed manner in a casing, delimiting a low-pressure chamber and a variable-pressure chamber, with respect to a pneumatic piston (16) over a certain travel. The displacement of the pneumatic piston being controlled by the skirt in a first direction when the skirt comes into contact with a first face of an annular plate (100) which is arranged in the low-pressure chamber and is fastened rigidly to the pneumatic piston, and the displacement of the piston in a second direction is controlled by an elastic means mounted in the low-pressure chamber and bearing by one of its ends on a second face of the annular plate (100).
摘要:
A pneumatic brake booster for use in a motor vehicle having a feeler (42) mounted to slide on a plunger (32) located at the end of a control rod (22) and pivoting key (62) for axially blocking the movement of the feeler (42) with respect to the plunger (32) during a normal brake application and unblocking the movement during an emergency brake application to reduce the length of a plunger-feeler assembly and thus increase the jump phase of an output force.
摘要:
A pneumatic servomotor for providing an assisted braking of a motor vehicle. The servomotor includes a plunger arrangement with 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) with a given clearance around the sleeve (58). The key (60) is driven by a moving piston (22) in response to a predetermined rate of speed being applied to a control rod (38) by an input force. The predetermined rate of speed causes the key (60) to rock and lock the sleeve (58) with respect to the piston (22) independently of the control rod (38). The unidirectional clutch device (56) comprises at least one locking transverse face (76) for engagement with the sleeve (58). The face (76) is axially directed rearwards from a front end of the sleeve (58) to form a stop for a peg (78) located on the key (60) that extends radially towards the sleeve (58) for axial indexing an end locking position for the sleeve (58).
摘要:
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).
摘要:
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).