Abstract: A power steering mechanism includes a control valve which acts both to control the flow of pressurized fluid to and from a pair of working chambers of the mechanism and as a pressure relief valve to limit the maximum pressure which may be communicated to the working chambers. The valve includes a stack of plane annular discs which are relatively rotatable and arranged coaxially with the control shaft of the steering mechanism. The discs are resiliently biased together and define valve ports and compartments which cooperate to control the flow of pressure fluid dependent upon the relative rotational positions of the discs. Rotation of the control shaft causes rotation of one of the discs relative to the others to correlate the ports and chambers so as to supply pressure fluid to one chamber and to vent fluid from the other chamber.

Abstract: A hydraulic brake booster defines a pressure chamber (24) and includes a control valve (26). A sleeve (40) on the control valve includes a spacer (58) and the control valve includes an annular member (60). The spacer is engageable with a booster housing (14) to limit movement of the sleeve and the annular member is engageable with an accumulator valve assembly (32) during a failure mode to provide a safety power assist. The spacer is also maintained in spaced relation to the accumulator valve assembly.

Abstract: A hydraulic brake booster includes a housing substantially defining a pressure chamber and movably supporting a control valve and a piston. An input assembly extends into the pressure chamber and cooperates with the control valve to communicate fluid pressure to the pressure chamber. The input assembly is pivotal relative to the piston to a first position wherein fluid pressure communicated to the pressure chamber acts against the piston to move the same while the input assembly remains substantially stationary in the first position. In particular, the input assembly includes a lever with a slot for receiving a portion of the piston. When the lever is pivoted to the first position, the piston portion moves within the slot from one end of the slot to the other end. A pair of springs extend between the housing and the piston and lever, respectively, to bias the piston and lever to a rest position abutting the housing.

Abstract: A wheel cylinder includes a housing defining a bore. A piston is reciprocably received in the bore and cooperates with the housing to define a pressure chamber. The wheel cylinder comprises a passage for supplying pressurized fluid to the pressure chamber from a fluid pressure source. The supply passage includes a first portion defined by an annular groove on the piston and a blind axial bore in the piston which communicates with both the annular groove and with the pressure chamber. A valve apparatus is received in the blind bore and modulates the fluid pressure supplied to the pressure chamber as a function of the fluid pressure provided by the pressure source.

Abstract: A vehicle load-leveling system includes a fluid actuated strut connected between the vehicle frame and axle. A piston moves to transfer actuating fluid to the strut in response power steering fluid pressure. A solenoid-controlled spool valve regulates communication of power steering fluid with the piston. Another solenoid-controlled valve assembly controls communication of actuating fluid with the strut. A height sensor cooperates with the solenoids so that selected amounts of actuating fluid are communicated to the strut to maintain the separation of the frame and the axle substantially between a predetermined range.

Abstract: A valve assembly is disposed between an accumulator and a pressure chamber in a hydraulic brake booster. The valve assembly operates to communicate the pressurized fluid to the pressure chamber when the pressurized fluid within the pressure chamber is insufficient to provide a power assist during braking. The valve assembly comprises a base which is received within a housing separating the accumulator from the pressure chamber. The base defines an opening leading to the housing bore and a body extends into the opening to define a clearance between the base and the body. The clearance leads to a recess on one end of the body which cooperates with a recess on the other end of the body to define a shear line for the body. The body is cut out on the one end of the body adjacent the recess to define a secondary passage and a portion of the body is movable after shearing into engagement with the base to substantially take up the clearance.

Abstract: A wheel cylinder comprises a bore closed by two pistons which define a pressure chamber therebetween. The pressure chamber is divided into two compartments by a partition member placed in the bore and which comprises a passage communicating the two compartments. One of the compartments is connected to a source of pressurized fluid and a control valve is mounted in the passage for controlling the pressure in the other compartment as a function of the pressure in the one compartment, whereby the wheel cylinder acts as a proportioning valve.

Abstract: A control system for hydraulic servomechanisms comprising a double-acting jack the working chambers of which are selectively and alternately connectable to a source of pressurized fluid and to a fluid discharge through a reactive switching valve which itself is operated by a control member.According to the invention, there are provided between the valve and each working chamber of the jack means for intercepting the passage of fluid toward said chamber as long as the upstream pressure does not reach a predetermined threshold value.The application may be advantageously used in power-assisted steering systems for automotive vehicles.

Abstract: A suspension member is pivotally secured to a vehicle frame at one end and is connected with a wheel assembly at the other end. In order to connect the wheel assembly to the suspension member, at least one ball joint is fixed to the suspension member for releasably engaging the wheel assembly. The ball joint includes a socket, a bearing and a stud. The socket defines a cavity for receiving the bearing and the stud extends radially outwardly from the socket. Before the ball joint is assembled, the socket is welded to the suspension member. Next, the socket is machined to define a contoured surface within the cavity which mates with the bearing as the bearing and stud are disposed within the socket cavity. Finally, the socket is deformed to trap the bearing and stud within the cavity.

Abstract: A hydraulic brake booster includes a housing which defines a pressure chamber and a piston within the housing is movable in response to pressurized fluid within the pressure chamber to effectuate a brake application. The piston encloses a storage chamber and forms a passage communicating the storage chamber with the pressure chamber. A valve member is disposed within the passage to control communication between the storage chamber and the pressure chamber. An operator actuator cooperates with a control valve to communicate pressurized fluid to the pressure chamber and a finger is actuated by the operator actuator to engage the valve member, thereby opening communication between the storage chamber and the pressure chamber. The valve member comprises a unitary assembly having a sleeve sealingly engaging the wall of the piston passage, a seat member biased into engagement with a shoulder defined by a stepped bore on the sleeve, and a stem extending through a bore on the seat member.

Abstract: A disc brake assembly includes a rotor and a pair of friction elements which are engageable with the rotor to retard rotation of the latter. A support carries the rotor and movably disposes the pair of friction elements adjacent the rotor. An actuator is pivotally mounted on the support and is provided with a cam member to urge the pair of friction elements into engagement with the rotor as the actuator moves from a neutral position to a braking position. The actuator includes at least one friction pad which is engageable with the rotor to move the actuator from the neutral position to the braking position. An input member on the actuator is operated by a vehicle operator to control the engagement of the one friction pad with the rotor. The actuator rotates about its pivotal mounting on the support and in the direction of rotation of the rotor when it moves from the neutral position to the braking position.

Abstract: A universal joint between a pair of members provides for transmitting torque between the pair of members when the pair of members are oriented at varying angles relative to each other. One of the members terminates in a cavity which is substantially cylindrical. The other member extends into the cavity and a pair of sockets cooperate with the other member to secure the latter within the cavity. The pair of sockets includes outer surfaces which substantially match the wall of the cavity to enable the pair of sockets to rotate in a first plane relative to the one member. The pair of sockets include projections which are received in an opening on the other member to enable the other member to pivot relative to the pair of sockets and the one member in a second plane substantially perpendicular to the first plane. At least one spring clip cooperates with the other member and the pair of sockets to bias the pair of sockets into engagement with the wall of the cavity.

Abstract: A disc brake assembly includes a torque member which carries at least one pin for slidably supporting a caliper. The one pin threadably engages the torque member and extends on both sides of the disc. A pair of friction elements are engageable with the disc to retard rotation of the latter. On one side of the disc the one pin slidably engages the caliper, while on the other side of the disc the one pin slidably engages one of the pair of friction elements. The one pin is spaced from the caliper on the other side of the disc where the one pin engages one of the pair of friction elements. The one pin cooperates with a resilient bushing on the caliper to form a sliding connection therebetween and also cooperates with a resilient bushing on the one friction element to form a sliding connection therebetween. An optional thermoplastic sleeve may be disposed between the resilient bushing on the caliper and the one pin.

Abstract: The object of the invention is a synchronized hydropneumatic control of clutch and gearbox.In accordance with the invention a hydropneumatic servomotor clutch control has been provided which includes a jack the piston of which is assisted by a pneumatic motor and a master cylinder which feeds the said jack with hydraulic fluid and controls the feed of air to the said motor, characterized in that the control chamber of the said jack is connected to the hydraulic circuit for locking/unlocking the gearbox, the feed to the said circuit being carried out through a valve mounted in the piston. The admission of the hydraulic fluid from the master cylinder having as its effect during a first period the closing of the said valve, thus interrupting the admission of fluid into the said chamber, then the causing of the transfer of the fluid contained in the latter towards the circuit for the gearbox which becomes unlocked in synchronism with the clutch.Application to controls of clutch and gearbox of vehicles.

Abstract: A leveling device is attached to a vehicle to assist in maintaining a body assembly at its preferred height even when added weight is installed in the body assembly of the vehicle. The leveling device includes a housing which is connected to either the body assembly or a wheel mounting assembly and a piston which is movably supported in the housing extends therefrom to connect with the other of the body assembly and the wheel mounting assembly. The piston cooperates with the housing to substantially define a pair of chambers and a passageway within the piston connects the chambers with each other. A pressure source, such as a vacuum or low pressure air pump, is in communication with the passageway and a first valve normally closes communication between the pair of chambers and the pressure source.

Abstract: A wheel cylinder in a brake assembly includes a housing for movably carrying a pair of pistons. An intermediate wall of the housing separates the pair of pistons from each other and cooperates with each piston to substantially form a first chamber facing one of the pistons and a second chamber facing the other piston. An inlet communicates fluid pressure to the chambers via a first path and a second path within the housing. A pressure responsive member is disposed within one of the paths and is biased to a position opening communication through the one path. When the fluid pressure within one of the chambers reaches a predetermined value, the pressure responsive member is movable to restrict fluid communication to the one chamber while the fluid pressure within the other chamber is free to increase in value during actuation of the wheel cylinder.

Abstract: A master cylinder includes a bore communicating with a reservoir and movably receiving a pair of pistons. The pair of pistons cooperate with the housing to substantially form a pair of pressure chambers. An outlet port communicates one of the pressure chambers with a brake circuit and a valve assembly within the outlet port is responsive to the fluid pressure therein to vary communication to the brake circuit. A sleeve within the housing bore movably receives one of the pair of pistons and forms a clearance to communicate the valve assembly with the reservoir independently of the outlet port. The valve assembly is movable in response to a pressure differential between the pair of pressure chambers to close communication between the valve assembly and the reservoir and open communication between the one pressure chamber and the valve assembly independently of the outlet port so as to deactivate the valve assembly. The sleeve also forms an aperture communicating the reservoir with the one pressure chamber.

Abstract: A rack and pinion steering assembly includes a housing with a first bore for rotatably receiving the pinion and a second bore for movably receiving the rack. A support member slidably engages the rack and includes a pair of arms opposing the wall of the first bore to prevent separation of the support member and rack away from the pinion. A resilient cooperates with one of the arms to bias the support member to pivot about the other arm. An optional ring cooperates with the other arm to adjust the position of the support member and the rack to take up wear between the rack and pinion or between the rack and support member.

Abstract: A disc brake assembly includes a frame which is movably disposed relative to a rotor and a central opening on the frame carries a pair of friction elements facing opposite sides of the rotor. An adjuster assembly is disposed within the central opening to control the position of the pair of friction elements relative to the rotor. The adjuster assembly includes a lever pivotally engaging the frame and an extendible assembly cooperating with the lever and frame to control the pivotal position of the lever relative to the frame. An actuator extends into the central opening and is engageable with one of the friction elements and the lever. Upon operation of the actuator, the one friction element separates from the lever to engage the rotor and the frame moves to engage the other friction element with the rotor. A pawl is responsive to movement of the actuator to control extension of the extendible assembly.

Abstract: A drum brake assembly includes a pair of brake shoes which are movable from a non-braking position to a braking position in engagement with a rotatable member. A hydraulic actuator is engageable with the pair of brake shoes to move the latter to the braking position and a strut extends between the pair of brake shoes to substantially define the non-braking position. The strut comprises a unitary sleeve with a bore for receiving projections extending from the pair of brake shoes. The bore is stepped with a threaded portion and a tapered diameter portion. The threaded portion engages one of the projections on one of the brake shoes such that rotation of the unitary sleeve by a pawl causes the unitary sleeve and other brake shoe to move away from the one brake shoe. The unitary sleeve is radially expanded at an intermediate location to define a ratchet wheel in engagement with the pawl.