Abstract: A compliance unit (8) for use in an hydraulic braking system is disclosed which is adapted to absorb hydraulic fluid from a master cylinder (1) during normal braking and, in the event that a fault in the braking system is detected the unit is adapted to return fluid to the master cylinder (1). The compliance unit (8) therefore effectively decreases its compliance in the event of a fault. The unit (8) may comprise a pair of pistons (14, 15) working in a stepped bore against a first and second biasing force, with a third variable biasing force provided to cancel out the second biasing force during normal operation to provide an increased compliance.

Abstract: A brake-pressure-transmitter arrangement (1) for a hydraulic motor-vehicle brake system, after an actuating force (F) has been introduced via an input member (brake pedal 2), by reduction in the volume of a hydraulic chamber (4) to be filled with brake fluid, provides a brake pressure at the output of the hydraulic chamber (4) for at least one wheel brake (3). In addition to the hydraulic chamber (4), there is a hydraulic chamber (6) for brake fluid, and the volume of this hydraulic chamber (6) is likewise reduced after introduction of the actuating force (F). To amplify the brake force, an output of this additional hydraulic chamber (6) is in fluid connection with the input side (10e) of a booster pump (10), which delivers brake fluid in the direction from the additional hydraulic chamber (6) to the at least one wheel brake (3).

Abstract: A power switching circuit includes first and second semiconductor switches providing parallel paths connecting a load across a power supply. A circuit maintains the second switch in an off state except when the current in the first switch exceeds a predetermined value.

Abstract: An axle journal (20), especially for the front axle of a front wheel drive motor vehicle comprises a main body (30) made of shaped sheet metal parts (32, 34) which enclose a circumferentially extending cavity (36). The cavity (36) houses portions (43) and (46) of mounting components (brake carrier member 42 and a combination 45 steering tie rod mount and transverse link seat) which portions stiffen the axle journal (20). The section of the cavity not taken up by the stiffening portions of the mounting components may be foam-filled. This composite-structure axle journal can be manufactured at low cost due to the reduced mechanical finishing required and can sustain heavy loads, whereby it meets present day requirements of lightweight construction.

Abstract: A reversible gerotor-type pump having an angularly moveable reversing ring rotatably supporting an internally toothed rotor which in turn cooperates with an externally toothed gear received within the rotor and rotatable therewith about an axis parallel to but spaced from the axis of rotation of the rotor, and, magnet means magnetically attracting the rotor towards the reversing ring so as to provide drag between the rotor and the reversing ring at least at the commencement of rotation of the rotor relative to the reversing ring.

Abstract: A solenoid-controlled valve assembly comprises a solenoid (1) for controlling operation of a spool valve (2), and the solenoid is contained within a solenoid body (3). The spool valve comprises a spool (40) working in a bore (41, 42) in a spool housing (12), and the housing is, in turn, sealingly received in a spool body (10). The housing (12) may be of differential area and may be sealingly received in a complementary stepped bore (11) in the spool body, with the housing arranged in such a manner that when subjected to equal pressures over different area a resultant force tends to urge the housing in a given direction. In a modification the housing (12) may be resiliently biased away from the spool body (10) and relatively towards the solenoid (1) by a resilient member such as an annular ring (70) of elastomeric material, or a spring washer (71).

Abstract: In an electrically-operated disc brake assembly for a vehicle in which a friction member (10) is applied to a brake disc by a brake-applying means including an electric motor (5) which forms part of the assembly and a linear actuator (15) in the form of a screw device apply an axially directed brake-applying force to the friction member (10) in response to operation of the motor (5), the linear actuator (15) comprises differential screws (16, 19) which translate rotation of the motor (5) into axial movement of the friction member (10) in a brake-applying, direction.

Abstract: An electronic braking system for trailers. A control system is incorporated into the braking equipment of a towing vehicle to provide a trailer braking command signal. This signal is regulated so as to balance the braking between the towing vehicle and the trailer through the assessment of forces in the coupling between the two vehicles. The assessment is made indirectly and is calculated from forces measured in the suspension components of at least two axles of the towing vehicle and the changes occurring therein during braking.

Abstract: A lock for a thrust reverser mechanism having actuator means for operating a thrust reverser mechanism, includes a first lock device connectable, in use, to the actuator means for preventing actuation of the latter. The first lock device is operable hydraulically to unlock the lock so as to free the actuator means for operation. An electro-mechanical second lock device is arranged so as normally to prevent actuation of the first lock device and is operable to permit actuation of the first lock device when required.

Abstract: An actuation unit for an electronically controlled hydraulic vehicle braking system, comprising a brake booster which can be actuated by a brake pedal and which comprises a master cylinder and a reservoir for hydraulic fluid, a first brake which is coupled with at least a first vehicle wheel and which is connectable with the master cylinder via an electronically controlled valve arrangement in a basic position or, in an actuation position is disconnectable from same, a brake pedal behaviour simulator which is connectable with the master cylinder and comprises a spring arrangement adapted to act against the hydraulic pressure from the master cylinder, and with which a characteristics modeling is associated.

Abstract: A fuel injector including a nozzle body having a bore defining a seating, a valve member having a plurality of passages providing fluid communication between the bore and a plurality of outlet openings, the outlet openings defining a first group of openings at a lower axial position on the valve member and a second group of openings at a higher axial position on the valve member. The valve member is slidable within the bore and is engageable with the seating to control fuel flow from the outlet openings. The outlet openings are shaped and orientated such that the sprays formed at the first and second groups of outlet openings do not interfere with one another.

Abstract: A vehicle braking system in which a stored volume of working fluid is used by a brake control system to apply the brakes under the control of an electronic control unit. The stored volume is replenished by pumping additional working fluid using a pump driven by an electric motor. The electric motor is periodically energized. An inferred value is established for the accumulator pressure based on an assessment of the motor response during the periods of energization. The electric motor can be arranged to be energized for short periods at predetermined intervals and the motor response during these periods assessed.

Abstract: A delivery valve includes a body defining a chamber into which from one end thereof extends a tubular support member. The interior of the member is connected to the outlet of a fuel pump and an outlet extends from the chamber to a fuel nozzle. Slidable about the support member is a first valve element which defines a seating in its end presented to the other end of the chamber. A second valve element is provided for engagement with the seating and a spring urges the first valve element into engagement with the second valve element. The first valve element also defines a surface against which the fuel pressure in the interior of the tubular member can act to lift the first valve element away from the second valve element to allow fuel flow from the outlet.

Abstract: A brake lining wear monitor is disclosed for a brake assembly having a body and a friction lining having an operative face adapted to be applied to a brake rotor. The monitor includes an actuator which applies the brake lining to the rotor, an adjuster driven by the actuator to maintain the linings in close proximity to the brake motor, and having a wheel, and a wear sensor responsive to actuation movement of the brake which is housed within the body of the brake itself without increasing the overall package size of the brake. The wear sensor is driven from the wheel of the adjuster with an end of the sensor remote from the wheel being formed into a connector to provide a compact and integrated unit which can be removed from the brake for service without dismantling the brake assembly itself.

Abstract: A control strategy for a multiple phase brushless motor (1) is disclosed in which the top (2, 3, 4) and the bottom (5, 6, 7) switching devices in two arms of the motor bridge are driven using complementary pulse width modulated waveforms, so that the top device (2, 3, 4) in one of the arms is in the ON state while the bottom device (5, 6, 7) is in the OFF state and vice versa. In an alternative arrangement, the control strategy described hereinbefore is used at high motor speeds while at low motor speeds a conventional modulation scheme is used in which a top switching device (2, 3, 4) in one arm of the bridge is in the ON state and a bottom device (5, 6, 7) in a different arm of the bridge is pulse width modulated. In another aspect, a method of calculating the position of the motor rotor is disclosed.

Abstract: A connector is disclosed which is intended for use with an injector. The connector comprises a projection defining an inlet passage sealed, in use, within a bore provided in the injector. The inlet passage communicates with at least one outlet passage. The connector further comprises at least one tooth received within a recess provided in the injector to secure the connector to the injector. The recess is conveniently defined by a body and nut forming part of the injector.

Abstract: A valve arrangement, comprising a first and a second fluid connection (16, 20) of respective, predetermined flow cross-sections, at least one valve element (44) which is biased by a first spring arrangement (106) in a first position in which the first and second fluid connection (16, 20) are communicating via a flow path, and a valve actuating means (42) by means of which the valve element (44) can be moved in order to assume a second position in which the first and second fluid connection (20) are closed against each other, is characterized in that the bias of the first spring arrangement (106), the force that can be applied to the valve element (44) by the valve actuating means (42), and the flow cross-sections of the fluid connections (16, 20) are dimensioned in such a manner that with a predetermined fluid pressure at the second fluid connection (20), the valve element (44) opens the second fluid connection (20) to such an extent that a flow path is obtained to the first fluid connection (16).

Abstract: A pressure regulator for use with a low pressure fuel pump comprises a pressure relief valve connected between the inlet and outlet of the pump to permit fuel flow from the outlet to the inlet upon the pressure difference therebetween exceeding a predetermined level, and an accumulator independent of the pressure relief valve communicating with the outlet of the pump.

Abstract: A variable speed rotary electric machine comprises a stator having windings and a rotor having windings mounted within the stator for rotation about an axis; a cooling fluid inlet into a first end region of the rotor; at least one first fluid duct having an inlet orifice in the first end region of the rotor and an outlet orifice arranged to discharge fluid onto a first region of the stator windings; and at least one second fluid duct having an inlet orifice in an opposite end region of the rotor and an outlet orifice arranged to discharge fluid onto a second region of the stator windings. A flow path extends through the rotor from the first end region to the opposite end region, the rotor windings being in the flow path. The machine also comprises at least one third fluid duct having an inlet orifice in said opposite end region of the rotor and an outlet orifice.

Abstract: A control strategy for a multiple phase brushless motor (1) is disclosed in which the top (2, 3, 4) and the bottom (5, 6, 7) switching devices in two arms of the motor bridge are driven using complementary pulse width modulated waveforms, so that the top device (2, 3, 4) in one of the arms is in the ON state whilst the bottom device (5, 6, 7) is in the OFF state and vice versa. In an alternative arrangement, the control strategy described hereinbefore is used at high motor speeds whilst at low motor speeds a conventional modulation scheme is used in which a top switching device (2, 3, 4) in one arm of the bridge is in the ON state and a bottom device (5, 6, 7) in a different arm of the bridge is pulse width modulated. In another aspect, a method of calculating the position of the motor rotor is disclosed.