Abstract: A trailer braking system for a towing vehicle has a trailer braking valve (26) is fed with a pressurized air supply which is modulated by the opening of the valve, as controlled by a first control pressure regulated by a trailer braking controller (24) in accordance with braking demand signals, to produce a trailer braking pressure. In order that a trailer braking pressure may be generated even if the above trailer braking valve control fails, the valve is supplied with a second control pressure independently of the first, and which is also capable of operating the trailer braking valve (26). In a preferred embodiment, the second control pressure is supplied from a braking line of the towing vehicle, such that the "back up" control pressure is a function of the towing vehicle braking.

Abstract: In an hydraulic braking system for a vehicle the rear wheel brakes are adapted to be applied by a fluid pressure generated by, and dependent upon, the pressure applied to at least one of the front wheel brakes. Control of the rear wheel brakes may be achieved by a fluid power unit under the control of at least one solenoid-operative valve which, in turn, is responsive to signals from sensing means responsive to the behaviour of the rear wheels.

Abstract: For measuring the rotational speed of a wheel is an antilocking protected vehicle brake system a rotational speed sensor is provided in which in accordance with the rotational speed of the wheel signals are electromagnetically induced which have an amplitude and frequency which increase regularly with the rotational speed. When due to error sources the amplitude of the induced signal does not increase with the frequency of the signal a rotational speed measured value is determined by means of the measured amplitude, i.e. not on the basis of the measured frequency. To avoid erroneous measuring signals it may likewise be provided that when the amplitude of the signal does not increase with its frequency the last measured value of the frequency of the induced signal at which the amplitude still increased with the frequency is used to determine the speed of rotation.

Abstract: A starting aid for a diesel engine comprises a housing (10) having a longitudinal passageway (12). Fuel is admitted to an upstream section (13) of the passageway via an inlet opening (14) and the fuel exits a downstream section (16) of the passageway via outlet openings (17). An electromagnetically-controlled plate valve (18) regulates a flow of fuel from the upstream, to the downstream section of the passageway, and a helical heater coil (32) heats the fuel as it passes along an annular part (31) of the downstream section (16) of the passageway (12).

Abstract: A clip for securing the inlet of a fuel injection nozzle within a tubular outlet extending from a petrol supply manifold has a pair of spaced side plates which are interconnected by a bridging member. The side plates have internal ears which locate in slots on opposite sides of the injector, slots in the side plates which receive a rim on the tubular outlet. The side plates are extended to define tongues which extend into engagement with the surface of the manifold to locate the clip and therefore the injector in a predetermined angular relationship in the tubular outlet.

Abstract: A fuel pumping apparatus has a pumping plunger operable by a cam to deliver fuel to an outlet. A spill valve is provided which when open permits fuel to spill from the bore in which the pumping plunger is located. An actuating piston is located in a first cylinder and is coupled to the spill valve and a storage piston is located in a second cylinder connected to the first cylinder. A control valve controls the pressure in the first cylinder and when the pressure is raised the actuating piston lifts the spill valve from the seating and the fuel from the bore can flow into the first cylinder and when the actuating piston is displaced therefrom, into the second cylinder.

Abstract: A first control valve which is normally open connects a master cylinder connection to a wheel cylinder connection. A second control valve which is normally closed connects the wheel cylinder connection to a storing chamber for returning brake fluid and to an inlet passage of a return pump when it is in open position. The return pump communicates through an output passage with a damping chamber. The damping chamber is arranged in a valve receptacle for the first control valve, and the storing compartment is arranged in a valve receptacle for the second control valve.

Abstract: A compound disc brake comprises a pair of pressure plates with a ball and ramp camming mechanism, one of the plates comprises a driven plate keyed to a rotating axle shaft to be braked, and the other plate comprises a servo plate carried from the driven plate by the camming mechanism. The servo plate has a torque-transmitting structure in the form of a separate annular disc keyed to the outer peripheral edge of the servo plate. The torque-transmitting structure transmits torque applied to that region by a primary braking apparatus to the central region of the servo plate. Retardation of the servo plate by the primary braking apparatus causes the pressure plates to separate axially and move into engagement with relatively stationary braking surfaces in the brake housing whereafter servo braking occurs.

Abstract: A method of controlling the brake pressure in an antilock vehicle brake system in which rotational velocities of the vehicle wheels are measured and the brake pressure is modulated in dependence upon the retardation and the slip of a wheel on exceeding threshold values provides that for each braked wheel the difference between the vehicle reference velocity and a wheel reference velocity is determined for adjusting the length of the pressure maintaining or pressure diminishing phase in dependence upon the difference.

Abstract: The fifth wheel of an articulated vehicle comprising the coupling between a semi-trailer and a tractor is provided with measuring apparatus for measuring forces imparted from the semi-trailer. The apparatus comprises a sensing device for measuring horizontal loads, and a sensing device for measuring vertical loads. The signals from the sensing devices and are fed into an electronic controller, in turn to cause the brakes on the trailer to be applied to achieve balanced braking, anti-lock control, and traction control of the wheels. A tractor fitted with a braking system of the brake-by-wire type with a conventional semi-trailer, without modifications to semi-trailer or to the braking components of the semi-trailer can therefore be used.

Abstract: A method of manufacturing elements of active material for use in the construction of electrodes for secondary electro-chemical cells characterized by comprising the steps of:rolling active material mixture in a first direction to produce elongate strip,cutting the strip to define cut sheets of rolled material,transporting a cut sheet in said one direction on a movable end, first, conveyor,moving the movable end of said first conveyor to transfer said cut sheet to a stationary, second conveyor extending substantially perpendicular to said first conveyor,operating said second conveyor to transfer said cut sheet in a second direction substantially perpendicular to said first direction to a laminating station wherein the cut sheet is laminated with other cut sheets, and,rolling the laminated cut sheets in said second direction. An apparatus for use in the manufacture of active material elements is also disclosed.

Abstract: A method of controlling the brake pressure in an anti-lock vehicle braking system provides for determining the deviation of a control magnitude, such as the slip or retardation of a wheel, from a given rated value Sw in the course of a control cycle. A threshold value which is decisive for the pressure decrease at a wheel subject to the risk of becoming locked is changed for the next successive control cycle in response to the amount of the deviation of the control magnitude from the rated value.

Abstract: A rotary distributor type of fuel pumping apparatus has a distributor member 10 mounting cam actuated pumping plungers 14. During inward movement of the plungers an electromagnetically operable valve 32 is operated which when open allows fuel under pressure to open a spill valve 31. The spill valve includes a spring loaded piston 23 which has a projection 22 engageable with a seating to prevent escape of fuel from the pumping chamber. Fuel under pressure is allowed to act on the piston when the valve is opened. The piston is pressure balanced by a plug 27 which is slidable in a drilling 25 in the piston, the drilling being connected by a passage 26 to the pumping chamber. The plug is held against movement and its diameter is substantially equal to the seat area to achieve pressure balance.

Abstract: A valve block (10) includes fluid passages (12), valves (14), and connections (30,32,34) for fluid operated devices. Electromagnets (36) are attached to the valve block (10) for actuating the valves (14). A hood (40) covering the electromagnets (36) is placed on the valve block (10). An external plug group (42) is arranged at the hood (40) and comprises plugs (44) which are accessible from outside and serve for connection to sensors and the like. A second plug group (46) including plugs (48) is arranged within the hood (40), the plugs thereof being connected to the plugs (44) of the external plug group (42). A third plug group (50) including plugs (52) is arranged at the valve block (10), the plugs thereof being adapted for connection to the plugs (48) of the second plug group (46) by donning of the hood (40). The electromagnets (36) are connected to the plugs (52) of the third plug group (50) by a conductor arrangement (56). The hood (40) encloses a space (53) in which electronic components are received.

Abstract: The invention is drawn to a pump having a piston which is reciprocable within a cylinder. The cylinder has a closed end including a liquid outlet and port means to introduce a liquid into the closed end of the cylinder. The piston has on its peripheral surface a helical groove means fluidly connected to the closed end of the cylinder and a second groove to communicate the port with the closed end of the cylinder when the piston is in a position between a location in which the port directly communicates with the closed end of the cylinder and a location in which the port communicates with the helical groove means. The second groove in the peripheral surface of the piston is located between the helical groove means and the part of the piston adjacent to the closed end of the cylinder. The second groove also communicates with a cutaway portion in the wall of the cylinder that is coaxial with the axis of the port.

Abstract: In a multi-hole fuel injector of the VCO type the holes are larger at their inner ends than their outer ends, i.e. they taper in some way, to achieve a bushy spray without making the wall of the nozzle too thin. They can best be formed by electro-erosion machining.

Abstract: An actuator for the throttle of an internal combustion engine comprises a torque motor and a return spring. The spring provides a monotonically increasing return force for increasing throttle opening. The motor has a torque characteristic such that, for constant motor current, the torque decreases monotonically for increasing throttle opening. The actuator thus has a single-valued function of throttle position versus motor current and allows open loop control as well as stable closed loop control.

Abstract: A dual computer cross-checking system includes a control computer for controlling a process in accordance with input data and a monitoring computer. The two computers are interconnected to exchange check data on a cyclic basis, each computer carrying out a number of processing operations on the received check data before transmitting the data thus processed to the other computer. In addition, each computer checks the received check data against an expected value. An error condition is detected if the result of at least one of these comparisons is found to be incorrect.

Abstract: A fluid control device for a braking system has a fluid flow path between an inlet port (9) and an outlet port (10) controlled by a first valve (17,18), and a fluid flow path between the outlet port (10) and an exhaust port (11,12) controlled by a second valve (20,22) and a stepper motor (30) actuated by an electronic controller (2) for driving a valve control piston (22) to which a pilot inlet pressure is applied (23) according to driver braking demand (5A). The stepper motor (30) and pilot inlet pressure act in parallel on piston (22) to control operation of the valves and thereby regulate braking. The stepper motor may operate in response to one or more vehicle operational parameters (A,B,C,D) fed to the controller (7).

Abstract: An insulated gate bipolar transistor comprises a body of semiconductor material having four layers of alternate conductivity-type disposed between emitter and collector electrodes and an insulated gate for establishing charge carrier flow to a base region of the device adjacent the emitter region, the device further comprising a conductive path enabling charge carriers to flow from the emitter region to the base region upon turn-off. As a result the device exhibits an improved speed of turn-off.