Abstract: A reservoir assembly for a vehicle hydraulic braking system includes two chambers (2, 3) for the storage of hydraulic fluid. The reservoir assembly is provided with a structure for increasing the effective volume of one of the chambers (2), for example a bellows (12) or a bucket (30), and which may be operable in conjunction with the fitting of a filler cap (17) to seal a filler opening (5) for that chamber. This enables a volume of fluid to be accommodated in a chamber of increased volume, thereby substantially eliminating the possibility of volume in excess of a given volume from overflowing from the chamber (2, 3). When the reservoir assembly is installed in a vehicle braking system of a brake-by-wire electro-hydraulic type (EMB) having a first power circuit (51), and a second back-up hydrostatic circuit (60), the one chamber (2) supplies fluid to the hydrostatic circuit, and the other chamber (3) supplies fluid to the power circuit.

Abstract: An output stage for an electronic sensor including two transistors connected in series to a junction therebetween to form a push/pull arrangement relative to a pair of supply lines provided with fixed supply voltages that are different for each line that are connected with different ones of the two transistors. The junction between the two transistors being connected to a sensor output line. Each of the transistors is driven by a respective drive line from an amplifier which receives an input signal corresponding to a sensor input signal. A fault detecting circuit is provided which includes circuitry to detect an open circuit fault condition in either of the two fixed voltage supply lines to disconnect the signal drive line leading to the associated one of the two transistors which is connected to the respective supply line that has been detected to have an open circuit fault.

Abstract: A rotor for an electric machine, the rotor comprising: a rotor body having a plurality of axially extending, circumferentially spaced slots therein; at least one winding conductor disposed in each said slot; and a retainer located in each said slot radially outwardly of the or each said winding conductor for limiting radial outward movement of the or each winding conductor; wherein each retainer has a radially inwardly directed surface configured so as to locate the or each winding conductor in a predetermined position in its respective slot. The invention further resides in a retainer and in a method of manufacturing a rotor.

Abstract: A fluid flow system for supplying fuel to an engine, the system including a fluid flow valve having a valve element movable alternatively to a first operative position in which a relatively low fluid flow rate is permitted through the valve, for achieving a normal gradual shut-off of fuel supply, and a second operative position in which a relatively high fluid flow rate is permitted through the valve, for achieving a rapid emergency shut-off of fuel supply. Also disclosed is a fluid flow valve for use in the system. The invention has application in aircraft gas turbine engines.

Abstract: An annular sealing element (16) for sealing an annular gap between the inner surface of a cylindrical wall and a cylindrical piston which can be displaced axially relative to said wall and is arranged concentrically therewith, has two separate annular and axially adjoining parts (42, 44), of which the first part (42) consists of an elastomer material and the second part (44) consists of a rigid material. In order to ensure, in conjunction with a displaceable body of a valve, that the opening and closing behavior of the valve is as constant as possible, the two parts (42, 44) are connected to one another in a releasable manner, and the part (44) made of rigid material has an axial protrusion (46) which is formed integrally with it, runs around it in the form of a ring, passes more or less to the full extent through the part (42) made of elastomer material and has its end surface covered over to the full extent by the part (42) made of elastomer material.

Abstract: A spring assembly comprises a helical compression spring engaged between first and second spring abutments and a collar limiting movement of the second spring abutment away from the first spring abutment.

Abstract: A terminal clamp for a battery terminal post including first and second relatively movable jaws defining between them a passage for receiving a battery terminal post, and a screw-operated clamping arrangement for closing the first and second jaws about the terminal post, in use, to grip the post against the action of a resilient restoring force urging the jaws apart, the screw-operated clamping arrangement including first and second components in screw-threaded arrangement with one another, the first component being held against rotation relative to the jaws, the second component having a frusto-conical cam surface cooperable with corresponding part frusto-conical cam surfaces of the jaws, whereby rotation of the second component relative to the first component and the jaws causes rotational and axial movement of the frusto-conical cam surface of the second component relative to the part frusto-conical surfaces of the jaws either to close the jaws or to release the jaws.

Abstract: A fuel injector comprises a valve needle slidable within a bore and engageable with a seating to control the supply of fuel to an outlet opening, an end surface of the valve needle being exposed to the fuel pressure within a control chamber defined, in part, by a piston member moveable under the influence of a piezoelectric actuator. The control chamber may be supplied with fuel under pressure, in use, through a restricted flow path. The piston member may have an effective area exposed to the pressure within the control chamber which is greater than that of the needle.

Abstract: A fuel injector comprises first and second housing parts, the first housing part being located within a bore or recess formed in the second housing part, the housing parts defining therebetween an inlet chamber, a delivery chamber axially spaced from the inlet chamber, and a filtration flow path interconnecting the inlet and delivery chambers to remove particulate contaminants from the flow of fuel therebetween.

Abstract: An electrical power-assisted steering system comprising a brushless electric motor which has a plurality of phase windings connected at a star point and in which a switching device such as a relay is provided in at least one phase of the motor, the switching device being movable between a closed position in which current is able to flow in the phase winding and an open position which prevents current flowing in the respective phase in the event of a fault.

Abstract: A method of controlling the operation of a fuel injector of a fuel system using a control system of the type comprising an accelerometer associated with an engine and arranged to sense vibrations thereof, and monitor means arranged to monitor the output signal of the accelerometer to detect vibrations of the engine, is described. The method comprises applying a drive pulse to the injector, using the monitor means and the accelerometer to determine whether or not the application of the drive pulse results in combustion in the cylinder of the engine associated with the injector, and modifying the duration of the drive pulse to determine the minimum pulse length which must be applied to the injector to cause combustion.

Abstract: A fuel metering arrangement has a fuel flow metering valve, a pressure drop regulator valve arranged and operable to maintain the pressure drop across the metering valve substantially constant and a throttle device arranged and operable to regulate fuel flow upon failure of the regulator valve in an insufficiently closed or fully open position.

Abstract: An hydraulic braking system of the brake-by-wire type has an hydraulic pressure source comprising an hydraulic accumulator adapted to be charged by a pump. An accumulator isolating valve is so positioned and biased to correspond to the direction of flow from the accumulator to a solenoid-operated proportional valve. The valve is biased into a closed position in opposition to the flow from the pump to the accumulator.

Abstract: The invention relates to a vehicle brake system of a motor vehicle, with an electronically controllable brake booster, comprising a vacuum chamber and a pressure chamber which are separated from each other by a movable wall, a control valve arrangement which can be actuated by an electro-magnetic actuator, wherein a pressure difference between the pressure chamber and the vacuum chamber is adjustable, with the movable wall changing its position as a function of the pressure conditions in the vacuum chamber and in the pressure chamber, thereby actuating a master cylinder, with the electromagnetic being supplied with current signals by an electronic control unit during operation, which the electronic control unit generates as a function of driving dynamics conditions or external influences, characterised in that upon the presence of certain driving dynamics conditions or external influences, or combinations thereof which render the actuation of the master cylinder necessary with a predetermined probability with

Abstract: An electronically controllable brake booster with a vacuum chamber and a pressure chamber, which are separated from each other by a movable wall, a control valve arrangement which can be actuated by an electromagnetic actuation device, through which a pressure difference between the pressure chamber and the vacuum chamber can be adjusted, with the control valve arrangement, as a function of a current flowing through the electromagnetic actuation device, assuming a holding position in which the current ranges between a higher value and a lower value without the control valve arrangement leaving the holding position, a first pressure changing position in which the current is higher than the higher value, and a second pressure changing position in which the current is lower than the low value, characterised in that upon a changeover of the control valve arrangement from the holding position into the first or the second pressure changing position, or upon a changeover from the first or the second pressure changin

Abstract: An advance arrangement is described including an advance piston slidable within a bore and defining, with the bore, a control chamber. A restricted passage permits fluid to escape from the control chamber at a controlled rate. A pump supplies fluid to the control chamber, the rate at which fluid is supplied to the control chamber relative to that at which the fluid can escape controlling the position of the advance piston. The pump is independent of a feed pump used to supply fuel to the high pressure pump with which the advance arrangement is used.

Abstract: A fuel metering system having a fuel pump operable to supply fuel at high pressure to a metering valve from which metered fuel is fed, in use, via a pressure raising valve to a gas turbine engine, a spill valve connected between the high pressure (HP) supply upstream of the metering valve and low pressure (LPp), and a restrictor device connected between the spill valve and low pressure (LPp), the pressure (LPf) arising at or upstream of the restrictor device, which varies according to spill flow through the device from the spill valve, being applied to the pressure raising valve, such that the pressure required to open the pressure raising valve varies in response to the amount of fuel spilled by the spill valve.

Abstract: A valve comprises a valve member which is engageable with a first seating to control communication between first and second ports and a second seating to control communication between second and third ports. The second seating is provided upon a separate seating member.

Abstract: An actuator comprising a drive arrangement arranged to rotate a first drive member, the first member being in screw-threaded engagement with a second member, the second member being in screw-threaded engagement with a third, output member, wherein the screw-threaded engagement between the first and second members is such that, when the first member rotates at a given speed relative to the second member, the second member moves axially relative to the first member at a first speed, the screw-threaded engagement between the second and third members being such that, when the second member rotates at the said given speed relative to the third member, the third member moves axially relative to the second member at a second, higher speed. The invention also resides in an aircraft engine thrust reverser system utilizing one or more of the above actuators for deploying cowls of the system.

Abstract: A brake (10) for a hydraulic vehicle brake system has a housing (14) with a bore (18) which is formed therein and in which a brake piston (20) is received in a sealingly and slideably displaceable manner. The brake piston (20) is adapted to press a brake lining (32) against a brake disk (12) by means of hydraulic pressure. For sealing, the brake piston (20) is sealed off relative to the bore (18) by means of a sealing ring (26) made of elastic material. In order to optimize the adhesive and sliding properties between the sealing ring (26) and brake piston (20), the sealing ring (26) and/or at least that outer surface of the brake piston (20) which cooperates with the sealing ring (26) is coated with a lacquer which contains an organic binder and a solid lubricant.