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 tire pressure management system includes at least an axle enclosing a pressurized fluid, a hubcap supported by the axle and having an interior and an exterior, a rotary union axially aligned with the axle and mounted to the hubcap, the rotary union includes at least rotary union housing providing a central bore, a fluid conduit having upstream and downstream ends, a first bearing and a second bearing. Each of the bearings are in contact engagement with the fluid conduit via an inner race, and in pressing engagement with a bearing sleeve via an outer race, the bearing sleeve in pressing contact with the central bore; and a first and second seal, the first seal is disposed between the first bearing and the downstream end of the fluid conduit, and the second seal is disposed between the second bearing and the upstream end of the fluid conduit.

A rotary air connection for an automatic tire inflation system having an air pressure source, the rotary air connection comprising a stationary portion and a rotatable portion rotatably mounted to the stationary portion, the rotary air connection having a central channel with a one-way check valve disposed in the central channel so as to allow fluid to flow from the air pressure source in one direction through the central channel but not in the opposite direction toward the air pressure source.

The air transmission structure includes a statorhaving an annular outer wall with at least one aperture, an air inlet, and an air passage between the air inlet and the at least one aperture on the annular outer wallbiased against the non-rotating spindle. A housing includes interior annular walls mounted in radially spaced relation with the annular outer wall of the stator to form an annular cavity therebetween, and at least one aperture formed through the interior annular wall, and air outlet, and an air passage between the at least one aperture and air outlet. A seal is inserted within the annular cavity and defines a radial air passage between the apertures defined within the stator annular outer wall and the housing interior annular wall. An annular bearing between the stator and housing is configured to allow the housing to rotate with respect to the stator.

A rotary union assembly for use with a tire inflation system includes a hollow tube configured to deliver air between proximal and distal ends, a bullet having a central axial aperture receiving the tube therethrough, a proximal retaining structure defined on the proximal end of the tube, and a distal retaining structure defined on a distal end of the tube, configured to retain the bullet on the tube therebetween. A cartridge is coupled to a distal end of the tube and includes one or more apertures on a sidewall thereof in fluid communication with the tube. In use, the rotary union assembly is coupled between a non-rotating axle of a vehicle and the rotating hubcap of a tire rotating about the axle and may be removed as a unit for repair and/or replacement of wear parts on the assembly.

A wheel end high-temperature warning system for a vehicle having a wheel-end assembly mounted to an axle is described. The system may include a first temperature sensor including a sensor head configured for mounting within a spindle section of the wheel end assembly, the sensor head in a heat exchange relationship with a bearings of the wheel-end assembly. The system may further include a transmitter disposed on the axle to which the wheel-end assembly is mounted, the transmitter being configured to receive a first sensor signal from the first temperature sensor indicative of a wheel-end temperature and transmit the signal to a receiver. A vehicle data acquisition module may be coupled to the receiver, the data acquisition system being programmed to receive the first sensor signal and process the signal to determine a measured temperature of the spindle.

A steer axle spindle may have one or more channels formed therein. A rotary union may be mounted to a steer axle wheel end assembly. The rotary union may be sealingly connected to a pressurized fluid source through the channel, and sealingly connected to a vehicle tire.

A tire inflation system for a small trailer may include a fluid pressure source mountable to the trailer, and fluid conduits providing sealed fluid communication between the fluid pressure source and the small trailer's pneumatic tires. The system may further include a fluid connector configured for connection to an external fluid power source.

A vehicle axle assembly is provided having a hub which is mounted on a cylindrical axle body by way of a ball bearing so as to be rotatable about a central longitudinal axis, wherein the ball bearing has an inner race connected to the axle body and has an outer race connected to the hub. The vehicle axle assembly includes an axially inner shaft sealing ring and an axially outer shaft sealing ring which are sealingly arranged between the two races and which delimit a ring-shaped chamber between the two races a first pressure medium line which extends through the inner race or one of the two shaft sealing rings and which opens into the ring-shaped chamber; and a second pressure medium line which extends from the ring-shaped chamber through the outer race and which is configured to be connected to a wheel fastened on the hub.

A method for detecting a leak in a pressure vessel of a system including a plurality of pressure vessels in fluid communication with a common header comprises: reducing a fluid pressure in the common header to a first predetermined value below an operating pressure of the plurality of pressure vessels; gradually adding fluid to the common header at a first flow rate to increase the fluid pressure in the common header from the first predetermined value; monitoring, after gradually adding the fluid to the common header, the fluid pressure in the common header; and determining, based on the fluid pressure in the common header after gradually adding the fluid to the common header, a leak in at least one pressure vessel of the plurality of pressure vessels.