Abstract: In a valve assembly for a telescopic damper, comprising a piston with flow channels controlled by valve members located on opposite sides of the piston, axially directed, annular valve seats which cooperate with the valve members are provided on separately formed seat members positioned against the side faces of the piston and having apertures aligned with the piston channels.

Abstract: In a boot assembly for forming a dust seal between an axially movable guided member, such as a piston, and a guide member, such as a vehicle brake actuator housing, a seal which seals with the guide member is carried by a rigid carrier member and one part of the seal is movable relative to the carrier so as to be axially elongated and radially reduced in thickness during assembly thereby to reduce the force required to assemble the seal into position on the guide member.

Abstract: A sliding caliper disc brake comprises a torque member, a caliper member slidably mounted on the torque member for straddling a minor portion of the periphery of a rotatable disc, and an actuator for directly urging a friction pad against one side of the disc to cause the caliper member to slide relative to the torque member to apply by reaction an opposite friction pad onto the other side of the disc. The caliper member is slidably mounted on the torque member by a sliding connection which includes a pin element having a portion slidably received in one of the members. The latter pin element is connected to the other of the members by an arrangement which permits lateral displacement of the pin element with respect to the other of the members. Laterally extending friction surfaces are provided on the pin element and on the other of the members. The latter friction surfaces are axially biassed towards each other so as to provide frictional resistance to the aforegoing lateral displacement.

Abstract: A disc brake assembly for a vehicle comprises a first inboard and a second outboard rotatable disc which are both relatively fixed and spaced axially. Superimposed friction pads for engagement with opposite faces of the discs are guided in a common drag-taking member which takes the drag on the pads when the brake is applied. A mechanical expander mechanism is housed between and acts directly upon the oppositely directed inner friction pads for engagement with the adjacent faces of the discs to apply the said oppositely directed pads to the discs, and a clamp assembly extending over the peripheral edge of both discs comprises coupled beams. The clamp assembly incorporates an actuator acting between one of the beams and one of the remaining friction pads to apply that friction pad to the inboard face of the inboard disc, and the other beam acting on the other remaining pad to apply thereto a reaction force in turn to apply that pad to the outboard face of the outboard disc.

Abstract: An automatic slack adjuster for a vehicle brake linkage comprising a housing constituting a lever in the linkage, and the lever is angularly movable about the axis of a shaft to impart to the shaft a brake-applying rotary movement which it transmits to it through a meshing worm and worm wheel assembly. Automatic worm driving means are incorporated for rotating the worm for adjustment of slack in the linkage in response to relative movement between the lever and a relatively stationary part, and the worm driving means incorporates a connection having a degree of lost-motion equivalent to a desired braking clearance, and a spring-loaded clutch of the multi-plate type disposed between the worm and a slidable pawl connected to the stationary part. The clutch includes primary clutch plates and secondary clutch plates with each secondary clutch plate being provided with a tooth, and all the teeth being received in a common notch in the pawl.

Abstract: An hydraulically operated disc brake includes a yoke slidably mounted on a stationary member for movement in a direction parallel to the disc and two pistons for actuating the brakes. The first piston acts directly on a friction pad and the second piston acts directly on the yoke and indirectly on a second friction pad through the yoke. The yoke is mounted on the second piston and on a retaining member which extends between the yoke and the stationary member to locate the friction pads against radial movement. The retaining member is rigidly secured to the stationary member and a resilient connection is provided between the stationary member and the yoke.

Abstract: In a pressure differential warning actuator for detecting when a differential between the pressure of separate brake circuits of an hydraulic braking system exceeds a predetermined value, at least two separate pistons work in separate bore portions in a common housing and are movable between a neutral position when the predetermined value of the differential pressure is not exceeded and an operative position, in which an indicator mechanism is actuated, when the predetermined value is exceeded, and the pistons act through a lever ratio change mechanism to restore them from the operative position to the neutral position when the differential is reduced to less than the predetermined value.

Abstract: A pressure reducing valve for a vehicle braking system, comprises an inlet and an outlet communicating with each other through a radial port, and an elastomeric seal movable relative to the port between a closed position in which the seal covers the port and an open position. The seal is arranged to cover the port on the outlet side thereof so that the interface between the seal and the port is subjected to inlet pressure.

Abstract: A booster operated master cylinder piston for use in an anti-skid braking system includes a modulator piston located between the master cylinder piston and the booster valve assembly. In the event of a skid the pressure of booster fluid acting on the modulator piston is equalized across the modulator piston.

Abstract: A disc brake having a caliper mounted for sliding on a torque plate has a facility for forming a temporary pivotal connection between the caliper and torque plate so that the caliper may be supported by the torque plate when the sliding connection is released for servicing. The pivotal connection is preferably formed by inserting a pivot pin such as the pin which normally supports the friction pads into openings in the caliper and torque plate.

Abstract: A brake comprises a rotor which is permitted to float axially and a friction pad which is carried by a support. The support is movable towards and away from a braking surface of the rotor and is urged to a datum position under the action of a return force. A spring or other resilient device is provided which is yieldable when the return force exceeds a predetermined amount to permit movement of the friction member beyond its datum position to compensate for float of the rotor surface, the spring urging the friction pad towards the datum position when the return force is reduced below the predetermined amount.

Abstract: An anti-skid braking system including a plurality of independent solenoid energizing circuits which are controlled in accordance with the outputs of sensors on separate wheels of a vehicle, has a failure detection circuit comprising a timer triggered into operation each time any one of the solenoids is energized, and reset when a back e.m.f. generated by the deactivation of any solenoid is detected. If the timer is not reset within a fixed period the system is disabled and a warning lamp is energized. The system also includes a circuit utilizing the back e.m.f. signals for testing the system each time it is switched on.

Abstract: A disc brake caliper consists of a body member including a cylinder portion, and a bridge member attached to the body member by two bolts. The body and bridge members of the caliper abut one another at two pairs of parting faces lying in a common plane, aligned bolt holes for the two bolts being formed in the parting faces. The cylinder portion of the body member extends axially beyond the parting plane so that a recessed portion of the bridge member overlies but is spaced from the cylinder portion to form an air pocket which is adequately vented. The two parting faces on the body member can be machined simultaneously by means of two broaching tools which clear the cylinder portion.

Abstract: A sliding caliper disc brake comprises a caliper member adapted to straddle a minor portion of the periphery of a rotatable disc, a carrier member for fixing to a vehicle, guide means guiding the caliper member for sliding relative to the carrier member, and an actuator for directly urging a friction pad onto one side of the disc to cause the caliper member to slide relative to the carrier member to apply by reaction an opposite friction pad to the other side of the disc. The guide means includes a pair of pins connected to one of the members and slidable within respective openings in receiving means connected to the other of the two members. In order to locate the caliper member against undue movement about either of the two pins, each pin is a snug sliding fit within the respective opening. Furthermore, at least one of the pins or receiving means is connected to the associated member by a resilient element adapted to flex so as to limit forces transmitted between the pins and receiving means.

Abstract: In a power control valve assembly in which the position of an inlet valve member relative to its seat is controlled by a control rod extending through a passage terminating in the seat, an end portion of the control rod has a profile which gives a variable throttling of flow through the passage in dependence upon the axial position of the control rod. In the valve described the end portion of the rod has an end part of constant diameter connected to a further part of reduced diameter by a sloping shoulder. Two such valve assemblies are shown arranged in parallel and operated through a single resilient block and a balance beam.

Abstract: A control valve assembly for a vehicle braking system comprises a control valve having a control valve operating member operable to control communication between an inlet and an outlet, a pivoted lever arrangement subjected to an input force applied by a spring and applying an output force to the valve operating member, and a device for varying the lever ratio of lever arrangement in dependence upon vehicle loading. The input force applied to the lever arrangement by the spring is substantially constant and independent of vehicle loading, variations in the lever ratio varying the load transmitted to the valve operating member.

Abstract: In a disc brake in which the brake applying mechanism is actuated by movement of a first pull rod, the hydraulic actuator which effects movement of the pull rod comprises an assembly of piston and cylinder members of which one is rigidly fixed with respect to a housing and the other is movable relative thereto and acts on the first pull rod. A second pull rod is coupled to the first pull rod and is used for parking or emergency braking.

Abstract: In a liquid level contents indicator for a vehicle hydraulic system of the float-operated electric switch type manually operable mechanism for testing the circuit comprises a push-button located in an end closure cap for a reservoir and the push-button acts on contacts of the electric circuit through a resilient diaphragm which also acts as a return spring for the push-button and provides a seal between the push button and the cap.

Abstract: In an automatic slack adjuster for a vehicle brake, an adjuster member acts on a part of an adjustable strut assembly for maintaining a substantially constant braking clearance between a braking member and a rotatable braking surface, the adjuster member acting on the part through a driven ring, and an overload spring urges a clutch face on the driven ring into engagement with a complementary clutch face on the part so that the driven ring and the part are movable together unless the reaction between the clutch faces exceeds the loading of the overload spring whereafter the driven ring can rotate relative to the strut assembly to preclude adjustment.

Abstract: A brake assembly comprises opposed brake parts arranged to be applied in unison to associated rotor surfaces. Each brake part comprises a friction pad or shoe and an adjustable length strut which transmits brake-actuating forces to the friction pad and which adjusts the position of the friction pad relative to the rotor surface to compensate for wear. Also provided is an equalizing device which ensures that the lengths of the adjustable struts are adjusted equally.