Abstract: A master cylinder for an hydraulic pressure system has a pressure cylinder (1) on which is mounted a reservoir (11), the cylinder having an open end closed by a cap (3). The cap is positively coupled to the cylinder (1) by a coupling device (26) arranged so that resulting from pressure applied to the interior of the cap (3) is transmitted via said device to the cylinder.

Abstract: The characteristics of an energizing voltage pulse and of the spark discharge in an ignition device for a gas turbine engine are monitored by providing a voltage whose magnitude and duration correspond to those of an electrical field in the ignition device. An output signal is provided only when the duration and magnitude of the energizing pulse are respectively not greater than and not less than predetermined values, and when the time integral over a preset period of spark discharges in the device is greater than a predetermined value.

Abstract: A fluid powered actuator system includes two identical fluid powered actuators operable by respective supply pressures which are controlled by respective identical valve arrangements. Operating positions of flow control elements of the valve arrangements are applied through respective couplings to a differential arrangement which operates, if these positions differ by an unacceptable amount, to apply an error indication through respective coupling to prevent the supply pressures from being applied to the respective actuators.

Abstract: A liquid fuel pumping apparatus of the rotary distributor type has a rotary distributor which is also axially movable to determine the quantity of fuel supplied by the apparatus. Inclined stop surfaces are provided to limit the outward movement of the pumping plungers during the filling strokes and an axial reaction is applied to the distributor member when the surfaces engage. The axial position of the distributor member is controlled by applying fluid pressure to one end thereof, the fluid being supplied to a chamber. A supply pasage to the chamber includes a check valve and escape of fluid from the chamber is controlled by a sleeve which covers a port. When the axial reaction is applied the port is closed by the sleeve and the check valve closes to form a hydraulic lock.

Abstract: A wedge and roller actuator, primarily for a vehicle drum brake, has a wedge disposed between opposed tappets with interposed thrust-transmitting rollers. Inwardly directed thrust arising on one of the tappets is transmitted to a fixed surface of the actuator housing either by additional rollers or by one of the rollers. In the latter case, the surface of the housing reacting the inwardly directed force is inclined to the longitudinal axis of the wedge in the opposite direction to the opposed wedge surface.

Abstract: Direction of rotation of a device is sensed by means of a rotor which is coupled to the device and which carries at least two permanent magnets which are angularly spaced and present opposite magnetic poles to two sensors. One of the sensors is responsive to one only of the magnetic polarities to produce a voltage signal and the other sensor produces a voltage signal whose polarity is dependent on the polarity and direction of rotation of the magnet which induces that signal. The two detector voltage are compared and their correspondence or otherwise indicates the direction of rotation.

Abstract: A fuel pumping apparatus of the rotary distributor type has a spill control sleeve mounted on the distributor member. The sleeve is axially movable to vary the quantity of fuel delivered by the apparatus and in addition the distributor member is also axially movable by means of a pressure responsive piston, the pressure applied to which varies in accordance with the speed of the associated engine.

Abstract: An epicyclic gear arrangement includes a plurality of substantially axially aligned epicyclic gear trains each having two relatively rotatable output ring gears, a sun input gear and planet gears drivingly connecting the sun and ring gears. Adjacent ends of the ring gears are spaced to permit axial misalignment, the teeth of the planet gears have reducing cross sections in directions away from the planes of their median cross sections to permit effective driving engagement with the ring gears in the event of axial misalignment of the latter, and the sun gears of the gear trains are drivingly interconnected in a manner that permits their axial misalignment. The arrangement is intended for a drive between parts which may flex, as for example an aircraft wing and a control surface thereon.

Abstract: A dipstick assembly for an internal combustion engine comprises a first tube arranged to extend from an engine sump and housing a conventional dipstick, a second tube secured about a portion of the first tube and extending within the sump and a sensor at the end of the second tube remote from the first tube. Between the sensor and the first tube, the second tube is deformed so as to lie substantially on one side of the dipstick and the deformed portion of the second tube accommodates electrical connections to the sensor.

Abstract: A brake pad (34) has a rear surface (46) for support on an actuating member (32,64) of a disc brake and a braking surface (56) constituted by friction material (38). At least one hole (48) is arranged in the brake pad (34) at right angles with respect to the rear surface (46) to guide the brake pad (34) on a guide pin (60). A protective sleeve (54) for the guide pin (60) extends coaxially with the hole (48) in a direction towards the plane of the braking surface (56). The protective sleeve (54) is made of a material which wears down together with the friction material (38) and it is embedded, at least for part of its length, in the friction material (38).

Abstract: A missile flight control system includes a plurality of fins movable by actuators and a corresponding plurality of valves each of which regulates gas flow through a pair of outlets which are oppositely directed perpendicularly of the missile axis, the valve being operated by respective ones of the actuators.

Abstract: A closed loop vehicle deceleration control system comprising a plurality of pressure control channels controlled by a fed forward driver's demand signal representing a deceleration requirement, and a closed loop feedback circuit which is adapted to produce a deceleration error signal representative of the difference between a deceleration level demanded by the driver and the actual vehicle deceleration. The driver's demand signal is arranged to be adjusted by means of a correction signal dependent on an integral function of the deceleration error. Adjustment of the demand signals is made by way of a multiplier in which one input is the driver's demand signal and the other input is a correction signal derived from a deceleration integrator. The correction signal is provided continuously by the integrator which the closed deceleration loop is adapted to be disabled at any selected time by disconnection of the deceleration error from the integrator input.

Abstract: A disc brake comprises a pair of brake pads (34) each associated with either side of a brake disc (10). At least one brake pad (34) comprises a backplate (36) having at least one projection (40) which is free of friction lining and by which it is guided on a guide pin (46) for displacement towards the brake disc (10). The guide pin (46) is fastened at a brake carrier member (12), extends through the corresponding projection (40) into a protective sleeve (56) fixed to the same, and has a free end (54) adjacent the brake disc (10). The protective sleeve (56) is designed to be elastic in longitudinal direction and has an end (60) remote from the corresponding projection (40) of the backplate (36). This end (60) is fixed tightly at the free end (54) of the corresponding guide pin (46). The fastening of the guide pin (46) at the carrier member (12) is releasable.

Abstract: A pulse generating circuit for a plasma ignition system includes a thyristor connected between a supply terminal and earth. A primary winding (Wp) of a transformer (TR) and a first capacitor (C.sub.1) are connected across the thyristor. The supply terminal is also connected through a secondary winding (W.sub.s) and a diode (D) to an output terminal. A saturable core inductor (L) and a second capacitor (C.sub.2) are connected in series across the output terminal and earth. A plasma plug is also connected across the output terminal and earth. In operation, the first and second capacitors are charged and the thyristor is fired. A high voltage pulse is applied by the secondary winding (W.sub.s) to the plasma plug causing electric breakdown. The second capacitor (C.sub.2) then discharges through the inductor (L) and the plasma plug. Four alternative circuits are also described.

Abstract: A fuel pumping apparatus for supplying fuel to a compression ignition engine includes a high pressure pump to which fuel is supplied from the outlet of a low pressure pump of the vane type. The vanes of the pump are mounted in slots in the pump rotor and are spring biased outwardly. A cavity defined by the inner ends of the slots is connected by a spring loaded valve to the outlet when the output pressure is above a predetermined value and to a space in the housing of the apparatus through a valve when the output pressure is below said value. The space contains fuel which accumulates during the operation of the apparatus.

Abstract: In a disc brake of the spreading type, angular movement of the pressure plates to apply the brake is effected by a brake-applying member which co-operates with at least one of the balls comprising a rolling actuator body and located in complementary opposed recess in the two plates. The member may comprise a wedge disposed between a pair of balls and radially displaceable to separate the balls. Alternatively the balls may be received in openings in the inner ends of a pair of toggle links, or in a fitting or other member which can be withdrawn from the brake in a radial direction. In another construction a ball is received in an opening in a bell-crank lever of which one arm reacts against one of the pressure plates.

Abstract: A gas turbine engine fuel control has spill value responsive to an input control signal, for spilling fuel from a supply passage. A pressurizing valve controls flow from the supply passage to the engine, in response to the pressure in the supply passage. A throttle valve in series with the pressurizing valve maintains the pressure difference across the pressurizing valve substantially constant. A selector valve is operable to shut both the pressurizing valve and a shut-off element in the throttle valve.

Abstract: In an hydraulic anti-skid braking system in which a modulator is fitted to each front wheel brake with which it forms a separate braking circuit, a valve assembly is connected between the circuits on the downstream of the modulators, between the modulators and the front wheel brakes. The valve assembly is responsive to differential pressures applied to both front wheel brakes and is operative to restrict the rate of pressure increase applied to the front wheel brake which is at the higher pressure.

Abstract: A vehicle suspension strut 1 comprising a telescopic hydraulic damper 2 and coaxial main suspension spring 3 is fitted with a brake pressure control valve 23. The control member 22 of the valve is acted on by a lever 20 pivotally mounted on a bracket 18 fast with the damper body. The lever 20 supports the end of a tubular support 7 which is movable axially of the damper body and which carries the support plate 9 for the main suspension spring. A compensating spring 12 acts between a ring 13 supported on bracket 18 and an adjustable collar 14 mounted on the tubular element. The compensating spring 12 reacts part of the main suspension spring load onto the damper body, and the remaining suspension spring load is transferred to the body via the lever 20 which distributes the force equally between the bracket 18 and the control member 22.

Abstract: The present invention provides a brake actuation and adjuster system comprising means for applying brake actuation pressure both to a brake actuator member and to a pump. The pump is arranged to pump pressure fluid to an adjuster control valve and an adjuster actuator, and the brake actuator member is arranged to be moved by said brake actuation pressure to then open the adjuster control valve against the pressure of the pressure fluid after the brake actuator has moved to a predetermined release position. Thus, in one embodiment, brake actuation pressure primes the pump causing the pump to force pressure fluid to the adjuster actuator. If adjustment is necessary, it is effected until the adjuster control valve is opened to release the pressure fluid. Thus a simple, independent adjuster arrangement is provided which does not affect available brake performance.