A valve assembly for a tire inflation/deflation system includes a body having a control port and a tire port, and a valve member for fluidly connecting or disconnecting the control port with the tire port. In one embodiment, the valve includes a fluid-operated damper having a damper chamber for controlling a timing of the valve member. A vent valve is provided for permitting excess fluid pressure to escape from the damper chamber. In another embodiment, the valve member includes a diaphragm separating first and second fluid chambers. A vent passage and at least one resilient fluid pressure-operated valve element are provided for enabling fluid to vent from the first chamber to the second chamber. Multiple-redundant valve elements may be provided to form an isolation gap that restricts contamination of the valve assembly.

Disclosed herein are devices and systems for continuous control of tire pressure. In one aspect, a device for continuously controlling tire pressure includes a bracket, a fixed non-rotating member fixedly attached to the bracket, and a non-fixed rotating member rotatably attached thereto. The fixed non-rotating member has at least one first seal surface, the at least one seal surface configured to be in fluid communication with a compressed air source. The non-fixed rotating member has at least one second seal surface, wherein an air chamber defined within a volume between interacting the at least one first seal surface and the at least one second seal surface causes fluid communication between an interior space of the tire and the compressed air source.

An agricultural vehicle and method of controlling the same are provided, the vehicle having a motive power unit providing a driving torque to at least one driven wheel and having at least one tyre or track frictionally coupled with the periphery of the driven wheel. A vehicle operating parameter is controlled in dependence on the driving torque and a slippage characteristic relating the respective driving torque at which the frictional coupling between driven wheel and tyre or track begins to slip for a range of vehicle operating parameter values. The operating parameter is suitably a tyre pressure or track tension, and the control may involve reducing driving torque or increasing pressure/tension to prevent slipping.

A central tire inflation/deflation system (CTIS) with a novel valve that may deflate more quickly and may deflate to a lower pressure than the previously known central tire inflation/deflation system valves. Also, the present valve may not be temperature sensitive, at least because the present valve does not require trapped air behind a diaphragm to operate the valve. The present valve may be placed into existing CTIS's in place of existing valves, without modifying pneumatic lines of the existing CTIS's. Thus, the present valve may be operated by a single fluid flow line, receive pressure from the single fluid flow line, and exhaust to the single fluid flow line. A second communication line, either a pneumatic pilot line or an electrical line, is not necessary, which allows the present valve to be retrofit into an existing CTIS without adding weight or complication from additional components.

A wireless sensor for a wheel end assembly of a heavy-duty vehicle is provided. The wheel end assembly includes a wheel hub and a hub cap mounted on the wheel hub. The sensor includes mounting means disposed in the hub cap. Sensing means are mounted on the mounting means to sense at least one condition of the vehicle. A processor is mounted on the mounting means and is electrically connected to the sensing means to process data from the sensing means. Communication means are mounted on the mounting means and are electrically connected to the processor to communicate the processed data to a user. An electrical energy storage device is mounted on the mounting means and is electrically connected to the sensing means, the processor and the communication means, enabling the sensor to be independent from the vehicle power supply. The sensor also accommodates components of a tire inflation system.

A wheel end assembly having a spindle, a hub, and a rotary seal assembly. The spindle defines a spindle air passage, a vent passage, and a spindle hole. The hub defines a hub air passage. The rotary seal assembly fluidly connects the spindle air passage to the hub air passage. The vent passage fluidly connects an inboard cavity to the spindle hole.

A pressure medium supply device for a tire of a wheel unit, a wheel unit, and a valve arrangement for a rotationally fixed transition of a pressure medium supply device for a wheel unit are provided. The valve arrangement has a housing part through which a pressure medium can flow, a control piston, in particular an axially movable control piston which is received on the housing part, and a discharge element with an outlet for conducting the pressure medium. The housing part and the discharge element are received in a rotatable manner relative to each other. The control piston has a flow channel for the pressure medium, has a force application surface to which the pressure medium can be applied, and can be moved between a disengaged position and an engaged position. A pressure medium line can be established between the housing part and the discharge element in the engaged position.

A tire pressurization arrangement on a vehicle in which the pressurization of the tire is controlled by a vehicle control unit and the vehicle control unit is notified of a desired tire pressure or desired tire volume. An air flow rate in a supply line to the tire is established so that the time to pressurize the tire to the desired tire pressure/volume is calculable, or the time taken to pressurize the tire to an interval pressure/volume is calculable, said interval pressure/volume being between a current tire pressure/volume and the desired pressure/volume, and if the time to pressurize the tire to the desired pressure is exceeded, the control unit gives a warning signal and/or stops deflation or inflation.

A pressure and temperature compensated valve assembly includes a flow valve allowing inflation flow from a control port to a tire port and controlling deflation flow from the tire port to the control port. A throttle valve restricts deflation flow between the tire port and the control port when deflating the tire at high flow rates or when tire pressure is high, thus enabling the flow valve to be closed. The throttle valve includes a throttle diaphragm that throttles in response to flow from the tire port and which does not restrict inflation flow from the control port. The valve assembly further includes a temperature responsive member engaging the flow valve, and which deforms in response to a change in temperature in the valve assembly, thus negating temperature effects on the flow valve, allowing the flow valve to close at a consistent force across a range of operating temperatures.

A rotary union for a tire inflation system of a heavy-duty vehicle that includes energy harvesting structure for generating electricity to power electronic components of the heavy-duty vehicle. The energy harvesting structure is integrated with and protected by the rotary union. The energy harvesting structure includes components that are attached to respective static and rotatable components of the rotary union that generate electricity for powering the electronic components during rotational movement of the rotatable components relative to the static components during operation of the heavy-duty vehicle. The components of the energy harvesting structure can be entirely removed or separated and sealed from a flow path of pressurized air through the rotary union.