Abstract: A waste outlet fitting for a bath, basin, sink or the like comprises a tubular body in which a plug is captively mounted. The plug includes a part-spherical periphery which is complementary to a part-spherical seat formed in the tubular body. The plug may be rotated between the closed position shown and an open position in which the plug member stands up-right within the tubular body by application of finger pressure to the edge of the plug. The tubular body may comprise an outer tubular member and insert member as illustrated, or may be in the form of an integral plastics moulding.

Abstract: An anti-skid braking system incorporates a modulator assembly through which fluid from a source is supplied to a brake. The modulator assembly comprises a de-boost piston working in a bore in a housing, an expander chamber connected to the brake and defined in the bore between one end of the piston and a first valve, and a second valve for controlling the application to the piston of support fluid to determine the relative position of the piston in the bore, the second valve being manipulated in response to a skid signal. The operation of the first valve is controlled independently of the piston by a flow-control regulating valve which is arranged to open the first valve upon failure of a supply of support fluid irrespective of the position of the de-boost piston.

Abstract: A brake circuit for a vehicle having selectively brakeable rear wheels comprises separate master cylinders each connected to one rear wheel brake and separately operable by means of foot pedals. The outputs of the master cylinders are connected to a control valve which in turn is connected to front wheel hydraulic brakes of the vehicle. When either of the pedals is depressed without depressing the other pedal the control valve is effective to isolate the front brakes from the pressurized rear brake circuit. However, when the brake pedals are linked together by a plate so that both rear brakes are operated together with control valve establishes a communication between the output of one master cylinder and the front brakes, thereby allowing four wheel braking.

Abstract: In a master cylinder and servo booster assembly for a vehicle braking system a mounting plate is connected to the rear end of a vacuum operated servo booster. A tubular extension integral with the mounting plate extends sealably through the movable wall of the booster substantially to relieve the booster housing of braking reaction forces. Circumferentially spaced axially extending slots divide the extension into axially extending arms which are secured to the master cylinder housing at their free ends by the engagement of a radially extending projection on the end of each arm with an annular recess in the outer surface of the rear end of the master cylinder housing. A sleeve integral with the front shell of the booster housing encircles the ends of the arms and holds the arm ends in interlocking engagement with the master cylinder housing. Alternatively, projections on the master cylinder housing and recesses on the ends of the arms may be provided to secure the arms to the master cylinder housing.

Abstract: An hydraulic brake actuator comprises opposed pistons which work in bore portions in a housing and fluid pressure in a pressure chamber urges the pistons in opposite directions to separate adjacent ends of a pair of brake shoes. A pressure proportioning valve controls communication between pressure spaces constituted by the pressure chamber. The valve is normally open to equalize the pressure in the pressure spaces but closes at a predetermined pressure so that any further increase in pressure is operative in only one pressure space, the pressure in which space acting to keep the valve closed. In use in a brake of the one-leading one-trailing shoe-drum type the increased pressure acts on the piston which applies the trailing shoe to the drum, in order to equalize the torque.

Abstract: A convertible shoe having a sole and releasable upper strap portions. Anchoring means attached to the sole edge cooperate with ring means at the ends of the strap portions to releasable secure the upper and sole portions.

Abstract: An hydraulic actuator comprises a first piston and a second piston both working in a bore in a housing and the actuator incorporates a pressure proportioning valve. The valve comprises a valve head for engagement with a seating, first and second stems projecting from the head and through the first piston in each of two opposite directions, each stem being of an area smaller than that of the head, a seal between the first stem and the first piston, a first spring acting between an abutment adjacent to the seal and a shoulder on the first stem to urge the head in a first direction away from the seating and into engagement with a stop, and a second spring acting on an enlargement on the second stem also to urge the head in the first direction and to augment the force in the first spring. The second piston is provided with a longitudinally extending recess into which the second stem and the second spring both project.

Abstract: In an hydraulic system a solenoid-operated valve mechanism is used to control delivery of pressure fluid to a part of the system, the fluid being circulated by a pump from a reservoir through the valve mechanism and back. The valve mechanism has a solenoid-operated valve biassed open, and closed when the solenoid is energized to generate pressure fluid, the valve then being operated in response to the pressure and a pressure-responsive valve-opening mechanism, such that when the pressure rises above a first threshold level the pressure acts to keep the valve closed, until the pressure reaches a second threshold level at which the valve-opening mechanism is operative to cause the valve to open provided the solenoid is de-energized. The valve-opening mechanism comprises a valve which opens at the second threshold level to allow pressure fluid into a cavity defined by a piston to cause the pressure to fall and the valve to open.

Abstract: A collet for an automatic bar feed machine tool having an outer sleeve 20 and an inner sleeve 21 reciprocable in the outer sleeve, a spring 26 to bias the inner sleeve 21 away from the gripping region 28 of the outer sleeve. Bar stock 33 is gripped in the collet by the outer sleeve end 22 acting on the end 29 of the inner sleeve, the bar being fed through the collet and short ends 36 falling away from the collet during feeding so that bar can be continuously fed through the collet without having to stop the machine to remove short ends.

Abstract: A seal assembly primarily for use with the stern bearing of a ship comprises inner and outer face seal elements mounted on a rubber body for rotation with the propeller shaft. Any oil from the bearing which leaks past the inner element, or sea water which leaks past the outer element, enters a void space formed by pockets in the rubber body. These pockets are separated by inclined vanes which act as a centrifugal pump to expel the leakage material through a passage in a seat for the seals. The assembly can also be used in other applications where the leakage material is corrosive or is likely to cause blockages.

Abstract: A friction pad assembly comprises a backing plate having friction material secured thereto, and an anti-rattle spring having a bent portion intermediate its ends, the bent portion seating in a recess in the backing plate. To avoid problems caused by heat when the spring is held in place in the recess by the friction material and located before heat bonding of the friction material, the recess is accessible to secure the spring to the backing plate after the friction material is secured to the backing plate. The bent portion is preferably retained in position in the recess by its own resilience.

Abstract: Valve assemblies for single and dual circuit braking systems are described. An assembly for a single circuit (FIG. 1) has a primary piston provided with a normally open valve seat engageable by a deceleration sensing ball housed in the primary piston. An annular secondary piston is slidably mounted on the larger diameter end of the primary piston. Primary piston has an area (A.sub.2) exposed to outlet pressure in a chamber and a smaller area (A.sub.1) exposed to inlet pressure in a housing bore portion, and is capable of rearward movement against biassing of a spring. Rearward movement of secondary piston is restricted firstly by a flange on the primary piston and secondly by a step on the housing.

Abstract: An hydraulic booster has a housing provided with an input member, a boost piston, an output member, and connections to a source of pressure and a fluid reservoir. A force applied to the input member is transmitted to the output member and augmented by the boost piston in response to pressurization of a boost chamber controlled by a valve mechanism in response to operation of the input member. An auxiliary chamber is defined between the boost piston and the output member. In a first stage of operation to take up lost-motion in the system, the auxiliary chamber is supplied with fluid from the source to advance the output member relative to the boost piston through a distance determined by a limiting mechanism. In a second stage of operation the output member and the boost piston move together in response to pressurization of the boost chamber. The area of the boost piston on which the auxiliary pressure acts is greater than or equal to the effective area of the boost piston.

Abstract: A vehicle gas suspension system consists of a suspension unit, a high pressure reservoir, a low pressure reservoir and an electrically driven pump. Control valves are disposed in connection lines between the unit and the reservoirs for respectively controlling the flow of gas to and from the suspension unit so as to maintain the ride height of the vehicle at a suitably adjusted attitude irrespective of vehicle loading. The pump comprises a tubular barrel, a valve at one end of the barrel, and a piston and flexible seal which reciprocate in the barrel reservoirs. A vacuum relief valve in the wall of the low pressure reservoir allows air to be drawn into the reservoir from the atmosphere, and a dump valve opens to allow gas to flow from the high pressure reservoir to the low pressure reservoir when a maximum permitted pressure is reached in the high pressure reservoir.

Abstract: In an hydraulic booster for a vehicle braking system a boost piston provides an output force in response to pressurization of a boost chamber under the control of a boost valve mechanism, which controls communication between the boost chamber and a pressure source and the boost chamber and a fluid reservoir. The operation of the boost valve mechanism is controlled by pressure in a control chamber which is pressurized by operation of a pedal-operated input piston. A recuperation valve controls communication between the boost and control chambers, and is operated in response to movement of the input piston. Pressure in the boost chamber acts on the input piston to urge it in a direction to keep the recuperation valve closed. This enables the input piston to work in a bore in the boost piston, with the control chamber in the boost piston and forward of the boost chamber.

Abstract: In dual control assemblies for hydraulic braking systems of vehicles, the valve assemblies comprise a pair of control valves clamped together in side-by-side relationship in each of which a back-up piston works in a greater diameter portion and a hollow spool works in a smaller diameter portion of a stepped bore, the piston and the spool being operated by a push- or pull-rod in turn operated by a pedal. The spool controls communication between pressure spaces of the valves and their respective recuperation, inlet and transfer ports. The recuperation ports are connected to a common reservoir for fluid, the inlet ports are connected to a common hydraulic power source and the transfer ports are interconnected. Each pressure space is connected to a brake via an outlet port.

Abstract: Clips are known in which a worm wheel is meshed with teeth provided on an end portion of a band for encircling the member to be clamped, but such clips are relatively costly to produce and problems arise in maintaining the band threads meshed with the worm. Various clips are described in which an end portion of the band is provided on one side with external screw thread portions which are complementary to the internal screw threads of a nut through which the band end portion extends. The opposite end of the band may be integral with a body on which the nut is supported, or it may be identical to the first end portion also be meshed with the nut threads, so that both end portions of the band are drawn through the nut on turning of the nut.

Abstract: The invention is directed to an improved joint between building panels, e.g. molded roof panels for prefabricated bay windows, wherein the joint consists of a slot in the edge of one of the panels. The slot has side walls, each of which is at a different angle relative to the plane of the panel. The edge of the other panel is inserted into the slot and the respective side walls thereof are engaged by one side or the other of the edge of the other panel to locate the other panel in one angular position or another with respect to the plane of the first panel.

Abstract: In a fluid-pressure-operable relay valve a control piston works in a bore in the valve housing to control sequential communication between an inlet port and an outlet port, and between the outlet port and an exhaust port. An exhaust valve seating on the control piston is engageable with an exhaust valve member coupled to one end of a lever pivotally mounted in the housing, and a spring acts on the exhaust member to urge an inlet valve member towards an inlet seating surrounding the inlet port. Since the spring acts in opposition to fluid pressure at the inlet port, a relatively small `cracking force` is required to the urge the inlet member away from the inlet seating to open the inlet valve.In alternative constructions the inlet and exhaust members are combined into a single valve member which is urged directly by the spring towards the inlet seating.