Abstract: A braking system (110, 1110) operable to assess valve operation and a method including: an electronic control unit (132), a supply line (116, 1116) for connection to a pressurised fluid supply, a control line (124, 1124) for connection to a pressure demand, a modulator valve assembly (113, 1113) for controlling fluid supplied to one or more brake actuators (112, 1112), an electrically operable valve arrangement, which has a first state and a second state, wherein in the first state, the control line (124, 1124) is connected to the modulator valve assembly (113, 1113), and in the second state, the supply line (116, 11116) is connected to the modulator valve assembly (113, 1113), and a pressure sensor (128, 1128) positioned to monitor the pressure in the control line (124, 1124), wherein the electronic control unit (132) is operable to perform a testing cycle in which the electrically operable apply valve arrangement is moved to its second state, for a predetermined test pulse duration, and wherein the electron

Abstract: An electro-pneumatic vehicle braking system including a control line, a modulator valve for controlling the supply of pressurised fluid to at least one brake actuator, a primary valve assembly and a secondary valve assembly, the primary valve assembly and the secondary valve assembly each being fluidly communicable with a source of pressurised fluid, and each of the primary and secondary valve assemblies being fluidly communicable with a control valve assembly, the control valve assembly being configurable in a first configuration to enable fluid communication between the primary valve assembly and the modulator valve, to provide a pneumatic control signal to the modulator valve, in a second configuration to enable fluid communication between the secondary valve assembly and the modulator valve, to provide a pneumatic control signal to the modulator valve, and in a third configuration in which fluid communication between either of the primary and secondary valve assemblies and the modulator valve is prevented

Abstract: A vehicle braking system including a control unit (340) which is operable to communicate with at least one sensor (320, 350), the sensor (320, 350) being operable to provide signals corresponding to a characteristic of a vehicle to the control unit (340), and the control unit (340) being in communication with a brake demand source (300) to receive brake demand data, and the control unit (340) also being in communication with a plurality of wheel end units, each wheel end unit including a brake torque control unit (310) which is operable to control an associated brake actuator to apply a braking torque dependent upon a signal received from the control unit (340).

Abstract: An air suspension system of a commercial vehicle comprises an electronic control device with a level control valve device. A valve element is coupled to a drive element mechanically coupled to a vehicle wheel or axle. In a first relative position of the valve element and a counter valve element, a port for an air suspension bellow is blocked. In a second relative position, the port for the air suspension bellow is connected to a port for an aeration device. In a third relative position, the port for the air suspension bellow is connected to a port for a deaeration device. Control logic generates a control signal for an actuator which, when a level change is set by an operator, correspondingly changes the relative position of the valve element and the counter valve element or the relative position of the counter valve element and a valve housing.

Abstract: An electro-pneumatic vehicle braking system including a control line, a modulator valve for controlling the supply of pressurised fluid to at least one brake actuator, a primary valve assembly and a secondary valve assembly, the primary valve assembly and the secondary valve assembly each being fluidly communicable with a source of pressurised fluid, and each of the primary and secondary valve assemblies being fluidly communicable with a control valve assembly, the control valve assembly being configurable in a first configuration to enable fluid communication between the primary valve assembly and the modulator valve, to provide a pneumatic control signal to the modulator valve, in a second configuration to enable fluid communication between the secondary valve assembly and the modulator valve, to provide a pneumatic control signal to the modulator valve, and in a third configuration in which fluid communication between either of the primary and secondary valve assemblies and the modulator valve is prevented

Abstract: A method of adjusting test braking pulses during stability control of a vehicle (10) including the steps of: applying a first test braking pulse to at least one wheel of the vehicle (10), the application of the test braking pulse comprising operating a brake actuator (112) to apply a low level braking pressure of the wheel, determining a first longitudinal acceleration (ALong1) of the vehicle (10) during the test braking pulse, obtaining a second longitudinal acceleration (ALong2) indicative of the longitudinal acceleration of the vehicle (10) when a test braking pulse is not being applied, calculating a change in longitudinal acceleration during the test braking pulse, and determining whether the change in longitudinal acceleration is acceptable, and if not, adjusting the level of the braking pressure applied in a subsequent test braking pulse.

Abstract: A vehicle braking system including a control unit (340) which is operable to communicate with at least one sensor (320, 350), the sensor (320, 350) being operable to provide signals corresponding to a characteristic of a vehicle to the control unit (340), and the control unit (340) being in communication with a brake demand source (300) to receive brake demand data, and the control unit (340) also being in communication with a plurality of wheel end units, each wheel end unit including a brake torque control unit (310) which is operable to control an associated brake actuator to apply a braking torque dependent upon a signal received from the control unit (340).

Abstract: A mechanically actuated level control valve device for a commercial vehicle with an air suspension system is a level control valve and comprises a drive element that can be mechanically coupled to a vehicle wheel or axle. A valve element and a counter valve element have a first relative position, wherein the port for the air suspension bellow is closed, a second relative position, wherein the port for the air suspension bellow is connected to the port for the aeration device, and a third relative position, wherein the port for the air suspension bellow is connected to the port for the deaeration device. The valve element is coupled to a rotatable driveshaft of the level control valve by a drive mechanism. An integrated actuator changes the relative position of the valve element and the drive element or the relative position of the counter valve element and a valve housing.

Abstract: An air suspension system of a commercial vehicle comprises an electronic control device with a level control valve device. A valve element is coupled to a drive element mechanically coupled to a vehicle wheel or axle. In a first relative position of the valve element and a counter valve element, a port for an air suspension bellow is blocked. In a second relative position, the port for the air suspension bellow is connected to a port for an aeration device. In a third relative position, the port for the air suspension bellow is connected to a port for a deaeration device. Control logic generates a control signal for an actuator which, when a level change is set by an operator, correspondingly changes the relative position of the valve element and the counter valve element or the relative position of the counter valve element and a valve housing.

Abstract: A mechanically actuated level control valve device for a commercial vehicle with an air suspension system is a level control valve and comprises a drive element that can be mechanically coupled to a vehicle wheel or axle. A valve element and a counter valve element have a first relative position, wherein the port for the air suspension bellow is closed, a second relative position, wherein the port for the air suspension bellow is connected to the port for the aeration device, and a third relative position, wherein the port for the air suspension bellow is connected to the port for the deaeration device. The valve element is coupled to a rotatable driveshaft of the level control valve by a drive mechanism. An integrated actuator changes the relative position of the valve element and the drive element or the relative position of the counter valve element and a valve housing.

Abstract: An apparatus for controlling the stability of a vehicle including a controller which is adapted to detect when conditions exist under which vehicle rollover is likely and, when such conditions exist, to trigger an alarm signal or initiate a control intervention by means of which the vehicle travel is controlled to reduce the likelihood of vehicle rollover, wherein the apparatus further includes an accelerometer, the accelerometer being configured to measure the acceleration of the vehicle along two non-parallel axes.

Abstract: A method of operating a vehicle wherein the method comprises: using a distance sensor to determine the distance between a part of the vehicle and an object, and implementing a speed control procedure if the distance detected by the distance sensor falls below a first predetermined value, characterised in that the method further includes the step of operating at least one vehicle brake momentarily to apply a low level braking force pulse to the vehicle following the engagement of a reverse gear of the vehicle.

Abstract: A method of controlling travel of a vehicle equipped with an antilock braking system, including the steps of determining potential for one or more wheels to lift off the ground, deactivating the system in respect of the wheels with the lift off potential so the speed of these wheels is not taken into consideration when determining if anti-lock braking is required, applying a low-level test braking force to one or more of the wheels that has the lift off potential, monitoring the speed of the one or more wheels, and if the test braking force causes the wheel speed to fall below a predetermined percentage of the vehicle speed, triggering a stability alarm signal and/or applying a controlled braking force to reduce the vehicle speed.

Abstract: A method of controlling travel of a vehicle equipped with an antilock braking system, including the steps of determining potential for one or more wheels to lift off the ground, deactivating the system in respect of the wheels with the lift off potential so the speed of these wheels is not taken into consideration when determining if anti-lock braking is required, applying a low-level test braking force to one or more of the wheels that has the lift off potential, monitoring the speed of the one or more wheels, and if the test braking force causes the wheel speed to fall below a predetermined percentage of the vehicle speed, triggering a stability alarm signal and/or applying a controlled braking force to reduce the vehicle speed.

Abstract: An apparatus for controlling the stability of a vehicle including a controller which is adapted to detect when conditions exist under which vehicle rollover is likely and, when such conditions exist, to trigger an alarm signal or initiate a control intervention by means of which the vehicle travel is controlled to reduce the likelihood of vehicle rollover, wherein the apparatus further includes an accelerometer, the accelerometer being configured to measure the acceleration of the vehicle along two non-parallel axes.

Abstract: A control system for a vehicle includes a first electronically controlled vehicle system, a second electronically controlled vehicle system, and a control unit. The control unit controls operation of at least one component of the first electronically controlled vehicle system while the vehicle is moving and preferably also while the vehicle is stationary, and controls operation of at least one component of the second electronically controlled vehicle system only while the vehicle is stationary.

Abstract: A control system for a vehicle includes a first electronically controlled vehicle system, a second electronically controlled vehicle system, and a control unit. The control unit controls operation of at least one component of the first electronically controlled vehicle system while the vehicle is moving and preferably also while the vehicle is stationary, and controls operation of at least one component of the second electronically controlled vehicle system only while the vehicle is stationary.

Abstract: A method of affixing a plurality of tubes having oval ends into a plurality of corresponding oval openings of equal circumference in the header wall of a heat exchanger. The minor diameter of the tube ends is greater than the minor diameter of the header openings and the major diameter of the tube ends is less than the major diameter of the header openings. The tube ends are inserted into corresponding openings in the header wall whereupon the minor diameter of the tube ends is reduced and the major diameter of the tube ends is increased to create a substantially fully contacting fit around the circumference with said header openings. Ends of the tubes are welded to corresponding collar openings in the header wall to form a plurality of tube-to-header joints. Flux is applied to the air-facing side of the tube-to-header Joints, and molten solder is applied to the opposite liquid-facing side and flowed into any voids in the welded joints to substantially seal the joints against leakage of liquid.