Abstract: A wear indicator for a disk brake having a caliper that slides in a carrier to apply friction pads against a disk. The wear indicator comprises a continuous variation sensor, such as a capacitive sensor, connected to a monitor. The capactive sensor has first and second electrodes having a variable overlap area. A guide pin for the caliper forms the first electrode. As the guide pin moves during a brake application, the monitor periodically measures the overlap area to define a current operational output signal which is compared with a predetermined signal and when the comparison differs from a normal result a failure signal is provided to indicate that the disk brake in not properly operating.

Abstract: A power-assisted steering device having a piston located in a casing and driven by a rotational input from an input shaft. The piston has a sealing section for separating a first chamber from a second chamber and a transmission section. The transmission section having a U-shaped profile formed by two branches which are coplanar with the main axis of the casing. The branches form racks and mesh at respective geometric sites with toothed sectors which are integral with one another and an output shaft. A sleeve located in the U-shaped profile and connected to the piston prevents relative rotation of the piston and sleeve with respect to the main axis of the input shaft while allowing some relative radial translations with respect to the input shaft as the piston is moved in response to a pressure difference in fluids supplied to the first and second chambers to provide assistance in rotating the output shaft in response to an input applied to the input shaft.

Abstract: An electromagnetic valve for controlling a passage for a flow of fluid or for a difference in the pressures between an inlet (48;56) and an outlet (56;48), comprises a body (10;16;46) on which is arranged a solenoid coil (22), a bore (26) in which is slideably mounted valve member (30) progressively displaceable in response to actuation of the solenoid coil (22) between a first position and a second position. The valve member (30) and the body (46) comprises cooperating valve surfaces (54;62) defining the passage. One valve surface (62) has in axial section a variable profile so that the area of the passage, in a radial section is a predetermined function of the intensity of the current applied to the solenoid coil (22).

Abstract: The invention relates to a rotary hydraulic distributor comprising a primary rotary element (3) coupled to an actuating device and connected for rotation with a valve rotor, a secondary rotary element (5) coupled to a driven device and connected for rotation with a valve stator, the valve stator and the valve rotor mutually cooperating to control a double acting servomotor of the driven device, a limited relative angular displacement being permitted between primary and secondary elements (3, 5) on either side from a central rest position, and a reaction mechanism being provided in order to bias the primary element (3) toward the central rest position. According to the invention, the reaction mechanism consists of a pair of independent substantially U-shaped pistons (7) able to tilt within respectively one bore (12) of a pair of bores symmetrically provided in secondary element (5), the legs (15) of U-shaped pistons (7) engaging and biasing opposite radial ends (4) of primary rotary element (3).

Abstract: A variable rate shock absorber comprising a tubular working cylinder (10) destined to be mounted on a suspended part of a vehicle, a piston rod assembly (24) slidably received in the working cylinder (10) and having an end (34) destined to be mounted on a fixed part of a vehicle, the piston rod assembly (24) having at its free end a piston member (48) cooperating with the working cylinder (10) to divide the interior thereof into an upper (44) and a lower working chamber (56), a valve mechanism in the piston member (48) to permit controlled two-way flow between the upper and lower working chambers an electro-magnetic valve mechanism (62) disposed between the upper working chamber (44) and a reservoir (18) and selectively actuatable to allow fluid flow therebetween, the valve mechanism (62) comprising a first member (80, 114) slidably mounted with respect to a second member (72, 116) between a closed position and an open position, characterized in that the first member (80, 114) is movable into at least one par

Abstract: The present invention relates to a tandem rotary master-cylinder for a vehicle brake circuit comprising a body (10;102) in which a first vane (20;114) is mounted for rotation in response to rotation of an input shaft (12;100) in order to generate pressure in a first working chamber (18;126) formed in the body (10;102) and delimited in part by the first vane (20;114).According to the invention the master-cylinder further comprises a second vane (30;120) rotatably mounted in the body (10;102) and delimiting with the first vane (20;114) the first working chamber (18;126) the second vane being rotatable in response to rotation of the first vane (20;114) to generate pressure in a second working chamber (62;128).A rotary master-cylinder with braking assistance is also described.

Abstract: A hydraulic pressure generator comprises a body in which is formed a bore, at least one piston mounted slidably in the bore, an annular sealing mechanism located in the bore, and the piston being slidable from a rest position during operation of the generator to cooperate with the sealing mechanism and divide the bore into a working chamber connectable by an output passage to a hydraulic actuator. A refill passage is connected to a source of hydraulic fluid. The output passage is formed in part between a first surface fixed in the bore and a second surface formed on a member mounted in the bore.

Abstract: Recirculating ball mechanism comprising a body (10), an actuator shaft (16) rotatably mounted within the body (10) and turnable in response to rotation of an input shaft (12), an output piston (18) slidably mounted in the body (10), a bore (22) within the output piston (18) in which is received an end (26) of the actuator shaft (16), the bore (22) having an internal threaded surface (24), the end (26) of the actuator shaft (16) being formed with a threaded surface (28), a series of balls (30) located between the two threaded surfaces (24, 28) so as to operatively connect the actuator shaft (16) to the output piston whereby a given rotation of the actuator shaft (16) produces an associated displacement of the output piston (18) in the body (10), and mechanism (42, 44) for recirculating the balls (30) to a point of origin in the thread (28) formed on the actuator shaft (16) characterized in that the thread (28) comprises at least one closed loop (40) extending around the circumference of the actuator shaft (16)

Abstract: Variable ratio steering mechanism comprising a body in which is rotatably mounted an input shaft, a drive shaft having a longitudinal axis, and coupled to the input shaft so as to be rotatable therewith, an output member slidably mounted in the body, a screw mechanism connecting the drive shaft and the output member so that rotation of the drive shaft produces a corresponding displacement of the output member in the body, characterized in that the drive shaft is axially slidable with respect to the input shaft, the steering mechanism further comprising a displacement mechanism to selectively displace the drive shaft axially with respect to the input shaft, the displacement mechanism comprising a screw connection between the drive member mounted in the body.

Abstract: A variable rate shock absorber having the interior of a working cylinder divided by a piston into an upper and lower working chamber. The lower working chamber is connected to a reservoir by a bi-directional valve member. A solenoid valve housed in a hollow piston rod has an actuated state connecting the upper working chamber to the reservoir. The output of the solenoid valve is connected to the reservoir by an axially disposed telescoping cylinder passing through the piston and the bi-directional valve member. Other embodiments are also disclosed.

Abstract: The end zones (11) of the C-springs (9) of the resilient device for the centering and coupling with backlash of first (1) and second (7) coaxial rotary components form lugs (12) extending radially inward in order to cooperate with stop surfaces (15) in the first rotary component (1), and external shoulders (19) in order to cooperate with facing shoulders (18) formed in the inside wall (16) of the second rotary component (7), the shoulders (18) being angularly offset from the stop surfaces (15) and substantially contiguous with the latter in projection onto the median plane (M) of the device in the centered position of the rotary components (1, 7).

Abstract: The hydraulic distributor, of the type comprising, in each of two parallel circuits (.alpha., .alpha.'), between a pressure source (S) and a tank (R), two modulable restrictions in series (A, B; A', B'), comprises in addition, in each circuit (.alpha., .alpha.'), a first (C; C') and a second (D; D') fixed restriction adapted to be put into operation alternately in synchronism with the modulable restrictions downstream of each of the latter, the fixed restriction put into operation being the one directly downstream of the modulable restriction operated in its closing direction.

Abstract: A modulator assembly is interposed in a fluid circuit between a source (S) and a user device (U), said assembly being composed of a metering electrovalve (E) forming a first restriction (.sigma.1) in the fluid circuit, a pressure regulation valve (R), loaded by a spring (22), being subjected to the pressure of fluid delivered by the metering electrovalve to the user device and forming a second variable restriction (.sigma.2) between the outlet of the electrovalve (E) and a tank (33). The pressure regulation valve (R) is integrated into the metering slide (14) of the electrovalve.

Abstract: The torque sensor comprises first (11) and second rotary structures coupled respectively for rotation to first (5) and second (4) coaxial rotary members mutually coupled by a dead-travel resilient coupling (6), the rotary structures having adjacent zones each formed with a series of angularly spaced optical windows (13, 14) arranged to cross a light path, two corresponding windows belonging to each series being in partial overlapping relationship in the light path when the rotary members are in a relative neutral position.

Abstract: The piston of the generator (6, 8) has a smooth lateral surface and cooperates in sliding sealing engagement with a pair of seals (9a, 9b) fixedly mounted in annular grooves formed in the interior surface of the single bore (2) of the tubular body (1) of the generator. The bore opens at either end of the body and comprises, in its interior surface, at least one longitudinal groove (17) extending over the entire length of the bore, the bore being closed at one end by an obturator element (4) fitted onto the body (1).

Abstract: The system for generating braking pressure, consisting of a pneumatic assistance servomotor (2) mounted so as to overhang on a master cylinder (1) which it actuates by a tubular pullrod component (14) in which extends the control pushrod (11) of the distribution valve (10), incorporates a pre-assembled unitary valve assembly (10) screwed to the end of the tubular pullrod component (14) so as to connect the latter to the movable piston wall (6) of the servomotor, the valve (10) being linked by a cylindrical flexible sealing component (50) to a central annular zone (19) of the front wall (4) of the servomotor casing which is closed by a labyrinth filtering structure (80) with draining means (86).

Abstract: The distributor (10, 11), typically with a star-type rotor in a discoid stator, incorporates a valve means with an OR logic function (5, 5') of preselection of the direction of the reaction (22, 23) to be applied to the input component as a function of the relative displacement between the primary and secondary components of the distributor, formed in one piece with the distributor and consisting of pairs of edges cooperating between two cavities (39a, 39b) of the stator (28, 30) and a cavity (44) of the rotor (31) advantageously formed in a reaction arm (41) of this rotor and permanently communicating with the source of pressure (14) of the distributor via a restriction (4) which can be externally modulated. The restrictions (5, 5') providing the OR logic function come into operation first, before the actual distribution restrictions (1, 2, 3; 1', 2', 3') of the distributor supplying the assistance actuator (19).

Abstract: The distributor (10), typically with a star-shaped rotor in a discoid stator, comprises a reaction device (11) advantageously integrated in the distributor and providing the actuating member (17) of the distributor with a reaction opposite to the actuating torque exerted on this actuating member and proportional to the power-assistance force supplied by a jack (12) controlled by the distributor (10). A regulating valve (30, 31) is associated with the reaction device (11), being typically located upstream of the latter, and is put into effect when the reaction force applied by the reaction device reaches a maximum predetermined value, in order to limit the reaction force to this predetermined value.

Abstract: The distributor comprises a primary rotating member having a prolongating portion (11) surrounding coaxially the primary rotating member (5) and forms a seat for at least a C-shaped rection spring (27) the ends of which (48) resiliently been upon a radial finger (37a) secured to the primary member and cooperate in engagement with aperatures (43a) formed in the prolongating portion (11) of the secondary member, thus forming a lost-motion coupling between the two members.

Abstract: Two pistons (5, 8) are mounted in the same casing (1) so as to slide in a sealed manner, the two pistons (5, 8) being firmly fixed to one another and having corresponding actuating chambers (21, 22; 23, 24) which are separated from one another and are supplied sequentially by two distribution valves (A, B) which are situated in the casing (1) and are actuated by the input shaft (14). The second piston (8) is formed by an extension (7) of the first piston (5) and its corresponding actuating chambers (22, 24) are formed in the piston structure (5, 8) and by a housing (4) in the casing (1), respectively, the housing (4) being coaxial with the main housing (3) for the first piston (5). The two valves (A, B) are advantageously of the type having a star-shaped rotor (30, 40).