Abstract: A step-by-step controlled servomechanism of the type comprising a drive element movable provided with a plurality of receiver ports, and a fixed distributor to supply said receiver ports and having a number of transmitter ports capable of being connected, in pairs, respectively to the low pressure and to the high pressure, a fixed manifold having a plurality of manifold ports capable of communicating with the chamber of the drive element, all the receiver ports being capable of being made to open in succession into one of said manifold ports, selecting means capable of connecting, in succession by permutation and simultaneously, at least one pair of transmitter ports to the high pressure and to the low pressure, respectively, and at least one manifold port to the chamber of the drive element.

Abstract: A disc brake of the type comprising a caliper or frame member slidably and floatingly mounted on a fixed member by way of two guide keys is disclosed. According to the invention, the guide keys slidably cooperate with one of the members by way of guide surfaces and floatingly cooperate with the other member by way of a cylindrical surface cooperating with a substantially plane surface. Preferably, the lines of contact defined between the cylindrical surfaces and the plane surfaces are comprised in a plane substantially parallel to the disc faces and which lies between the faces or offset relative to the latter towards an actuator.

Abstract: A control circuit for delivering control signals to interrupt admission of the fuel-air mixture in the low speed and idle circuit of the carburetor of an internal combustion engine. The control circuit is operated according to the engine operating conditions. The control signal is delivered in response to comparison of a signal whose level is representative of the positive or negative variations in the duration of an engine cycle with a substantially periodic signal to generate a pulse shaped signal. The width of the pulses increases when the vehicle is accelerating and decreases when the vehicle is decelerating.

Abstract: The invention relates to a servomotor for assisting the operation of a power brake system. The servomotor includes in a housing a power-assisting part and a part forming a hydraulic master-cylinder. The power-assisting part is adapted in use to be connected to an external power source such as a vacuum source. A valve assembly operated by an operator-operated intake member controls the generation of a pressure differential across a driving piston by allowing air to replace the vacuum on one side of the piston. The master-cylinder part includes an assembly having two coaxial pistons. The first piston is attached to the driving piston of the power assist part whereas the second piston is actuated by the intake member. Both coaxial pistons project into a chamber which is divided by a sealing ring. The central piston is adapted to pass through the sealing ring in response to an input force from the input member to further pressurize the fluid in the outlet portion of the chamber.

Abstract: A power steering mechanism comprises distributing means for communicating fluid pressure to the compartments of a fluid motor associated with the steering linkage of the vehicle. Each distributing means comprises a ball valve member disposed in a chamber of a housing. The valve member is urged towards a first valve seat defined in a low pressure supply passage, by means of spring means, and towards a second valve seat defined in a high pressure supply passage by means of an extension of an actuating piston, said extension extending through the low pressure passage. The piston is moved by way of a sleeve disposed intermediate between the input and output members and connected thereto by means of a spline and screw arrangement. In response to a torque applied to the input member, the sleeve is allowed to move axially for displacing the piston and modifying the position of the valve member, thereby changing the value of the pressure transmitted to the associated compartment.

Abstract: A disc brake comprising a caliper carrying a pair of friction pads and including a hydraulic fluid motor which directly applies one of said pads against a corresponding face of a disc and, by reaction through a sliding connection between the caliper and a fixed support, the other pad against the other face of the disc is disclosed. Extraction of the pad adjacent of the fluid motor is possible through a radial aperture in the caliper by moving the pad in front of a recess provided in at least one of circumferentially spaced edges of the aperture, said aperture being offset towards the fluid motor. A removable heat shield is normally inserted between the fluid motor and its adjacent pad to avoid escape of the latter and to avoid boiling of the hydraulic fluid in the fluid motor due to heating of the brake.

Abstract: A power steering device has a distribution valve inserted between a high pressure source formed by a pump and a reservoir for creating a pressure difference in a fluid motor connected to the steering linkage, in response to application of a torque to the steering shaft of the vehicle, thereby providing assistance to operation of the steering linkage. A by-pass passage connects the high pressure output from the pump with the reservoir and the cross section of the by-pass passage is controlled as a function of the pressure difference between the chambers of the fluid motor. The means for controlling the cross section of the by-pass passage comprise a slidable piston disposed substantially transverse in the path of the fluid flow. The piston comprises grooves and lands for respectively allowing and interrupting fluid flow in the by-pass passage. The axial position of the piston is a function of the pressure difference.

Abstract: The invention relates to a control valve of a hydraulic booster having an inlet orifice adapted to be connected to a hydraulic pump, an outlet orifice adapted to be connected to an open-center valve, a working orifice connected to the booster pressure chamber and an exhaust orifice connected to the reservoir. The control valve comprises mainly a first and a second valve members respectively controlling fluid connection between the working and the exhaust orifices. The first valve member is secured to a cylinder which partly covers the outlet orifice when this valve member is unseated.

Abstract: A drum brake of the type comprising two brake shoes adapted to be spaced apart by a wheel cylinder. The distance between the ends of the shoes which cooperate with the wheel cylinder is automatically increased to compensate for the wear of the brake linings by an adjusting device which defines the rest position of the ends. The device comprises an extensible member of the screw and nut type, two annular resilient members which grippingly engage corresponding cylindrical portions of the extensible member, and a cam which rotates the resilient members one relative to the other in a first direction upon a brake application and in the opposite direction upon brake release to limit extension of the extensible member to a predetermined value.

Abstract: The braking correcting device of the hydraulic type comprises a housing in which is defined a cavity. A stepped piston is disposed movable in the cavity and has one end which projects outwards from the housing, the piston having a head slidable in a bore formed in the cavity of the housing for separating the cavity into an inlet chamber which adjoins the piston end face having the smaller effective cross sectional area, and an outlet chamber which adjoins the piston end face having the larger effective cross sectional area. The piston head contains a peripheral groove which receives with axial and radial clearance a ring of elastomeric material capable of disconnecting the two chambers when the piston moves a predetermined distance from its idle position which is fixed relative to the housing, overcoming a return force. The bore comprises a first portion having a fluid tight side wall adjoining the inlet chamber, and a second portion contiguous to the first portion and adjoining the outlet chamber.

Abstract: A disc brake comprising a piston mounted in a cylinder associated with a carrying member movable towards a rotary disc from an idle position to urge directly a friction pad towards the corresponding face of the disc is disclosed. The friction pad slidably cooperates with appropriate surfaces defined on two circumferentially spaced edges of an aperture provided in the carrying member, at least one of the edges comprising a slot offset towards the piston relative to the appropriate surfaces to permit radial extraction of the pad when the latter is brought opposite the slot. The piston is adapted to be pushed back away from the disc towards its idle position in opposition to an automatic adjuster associated with the piston to permit radial extraction of the pad by introduction of a tool between the pad and the piston after removal of a wedge forming element normally inserted therebetween.

Abstract: A braking correction device comprising two correcting valves of which the inlets are separately connectible to two independent braking pressure sources and the outlets to two independent sets of brake actuators, each valve being capable of controlling the pressures at its inlet and outlet in accordance with a predetermined relationship and comprising a piston subject to resilient return spring. The correction device comprises force distributing member situated between the resilient return spring and the pistons of the correcting valves, the distributing member comprising a block of elastomeric material enclosed in a rigid shell comprising a cylindrical cavity in whose bottom the force distributing block is fitted, the cavity comprising a cylindrical edge slidable receiving an assembly comprising two projections contacting the block and co-operating with the pistons of the valves. The braking correction device is intended for a dual vehicle hydraulic brake system.

Abstract: The invention relates to a hydraulic servomotor comprising a housing provided with a bore slidably receiving two pistons separating an actuating chamber from an utilization chamber, said pistons including an annular outer piston and an inner piston received within the annular piston. Releasable coupling means are provided between both pistons to permit said pistons to move in unison when high pressure fluid is available in the actuating chamber and to permit the inner piston to be moved alone by the push rod in the event of a high pressure failure in the actuating chamber. The motion of the outer piston towards the interior of the actuating chamber is limited by an abutment fixed to the housing.

Abstract: The invention concerns a drum brake of the type comprising brake actuator inserted between two adjacent ends of two brake shoes, the opposite ends thereof cooperating with a fixed anchoring member. An adjusting lever is pivotable relative to one of the shoes upon wear of the linings carried by the shoes, to control relative rotation between two elements of an extensible member. According to the invention, a resilient means normally connect the extensible member to the one shoe and an adjustment limitor are provided to connect the extensible member to the lever when the relative motion between the free end of the lever and the one shoe exceeds a predetermined value.

Abstract: In a disc brake in which a movable member is slidably mounted on a fixed support member by means of at least one column at least one protecting device is associated to each column to prevent various particles such as mud, grease, etc. to be deposited on the sliding surfaces of the column. The protecting device includes a seal of resilient material which cooperates with the outside surface of the column by means of at least one lip, and which carries a rigid scraper element level with the outside surface of the column. The scraper element is mounted outside with respect to the lip of the seal to clean off the particles of solid materials in a first stage, the liquid particles being retained by the lip in a second stage.

Abstract: A disc brake of the type comprising a torque-taking member associated with an actuator is adapted to urge at least one friction element against a rotary disc. The friction element comprises a backing plate carrying a friction lining and anchors by its backing plate against guiding surfaces formed on the torque-taking member. An anti-noise spring cooperating with the friction element and with the torque member comprises a lock fixing the anti-noise spring axially with respect to the backing plate. A first portion of the spring traverses an aperture formed in the backing plate and cooperates with a second portion of the spring in such a way that the spring forms with the friction element a subassembly removable as a unit from the remainder of the brake.

Abstract: A solenoid valve is provided for controlling fluid communication in a passage defined between a first and a second orifices. A valve seat is defined in the passage and a valve member is adapted to be urged into contact with the valve seat to interrupt fluid communication between the first and second orifices. A coil and a fixed core control movement of the valve member in response to energization of the coil. The valve member is attached to a magnetized rod which is coaxial with the core. When the coil is not energized, the magnetized rod is normally attracted toward the fixed core in response to induced magnetization of the latter, to keep the valve member away from the valve seat. In response to energization of the coil, magnetization of the core is reversed and the rod 28 is repelled so that the attached valve member is urged into contact with the valve seat.

Abstract: In a disc brake of the type in which at least one fluid pressure actuated piston is associated with a caliper to urge a first friction element directly onto a first friction face of the disc, the caliper being slidable by way of at least one column on a torque-taking member to urge by reaction a second friction element on to the other side of the disc, a locking connection is provided between the second friction element and the column to immobilize the column with respect to the caliper through a removable support connection provided between the second friction element and the caliper. The locking connection is preferably comprised of at least one extension of the backing plate of the second friction element, this extension being designed to fit into a corresponding slot in the at least one column.

Abstract: Step by step controlled servomechanism of the cylinder-type comprising a drive element movable in a case which it divides into two chambers and provided with a plurality of receiver ports, a distributor adapted to be put in communication with the high pressure and the low pressure and to supply said receiver ports, wherein said distributor is fixed and provided with a number of supply or transmitter ports at least equal to three but independent of the number of receiver ports, the transmitter ports being capable of being connected by permutation, in succession and in pairs, respectively to the low pressure and to the high pressure, the distance between the receiver ports and their length, on the one hand, the distance between the transmitter ports and their length, on the other hand, being such that, by the step by step displacement in one direction of the drive element, on one hand, it is possible to bring each time at least one receiver port between the two transmitter ports of a pair in such position that

Abstract: A level indicator using an indirect method of measuring a gas pressure in order to check the level of a liquid such as the lubricant contained in the crankcase of an internal combustion engine. The level indicator includes preferably a liquid column gas-pressure gauge formed of a straight measuring tube having one end immersed in the barometric liquid contained in a reservoir, and an electrical heating resistance is located in the enclosure of the reservoir above the barometric liquid. The enclosure communicates with a tubular probe immersed in the liquid whose level is to be checked. Voltage applied to the resistance generates heat which as a result of the thermal expansion of the gas causes the gas-pressure in the enclosure to become sufficient for causing the gas to bubble in the liquid, so that the gas-pressure which is read off the pressure gauge is representative of the depth at which the probe is immersed.