A wheel hub assembly having a non-rotating outer bearing flange and an inner bearing flange disposed at least partially concentrically within the outer bearing flange. At least one rolling element is disposed radially between the outer bearing flange and the inner bearing flange. A port is disposed in the outer bearing flange, and a first conduit is disposed through the outer bearing flange in fluid communication with the fluid port. A second conduit is disposed through the inner bearing flange, wherein the second conduit is in fluid communication with the first conduit. A rotating spindle is disposed at least partially through the inner bearing flange, and the spindle is coupled for rotation with the inner bearing flange.

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.

Systems and methods for determining the health of a seal in a tire inflation system are provided. In one example, a method of determining the health of a seal of a tire inflation system on a vehicle includes obtaining one or more pressure measurements of a tire of the vehicle with a pressure transducer in communication with an electronic control unit and sending the one or more pressure measurements to a computer network via a communication network that receives signals from the electronic control unit, the communication network including a telematics device in communication with the computer network, wherein the computer network is configured to determine the health of the seal based on the one or more pressure measurements communicated by the telematics device.

The present disclosure relates a device that includes a rotary union body. Included with the rotary union body is a circumferential air channel, a seal channel, and an intake air channel. The intake air channel is connected to the circumferential air channel. Also disclosed is a hub assembly system that includes a hub and a rotary union body. Included with the rotary union body is a circumferential air channel, a seal channel and an intake air channel. Here the intake air channel is connected to the circumferential air channel.

The present disclosure relates a device that includes a rotary union body. Included with the rotary union body is a circumferential air channel, a seal channel, and an intake air channel. The intake air channel is connected to the circumferential air channel. Also disclosed is a hub assembly system that includes a hub and a rotary union body. Included with the rotary union body is a circumferential air channel, a seal channel and an intake air channel. Here the intake air channel is connected to the circumferential air channel.

A rotary union for a tire inflation system includes an axle housing and a wheel axle rotatably mounted in the axle housing. The wheel axle has a flange for attachment of a wheel rim. The wheel axle is received by a passage socket that is connected for conjoint rotation to the wheel axle and supported by a radial bearing relative to a bearing seat within the axle housing. A compressed air duct is disposed inside a cylindrical wall of the passage socket such that the compressed air duct is connected at one end to a pressure connector mounted on the axle housing and at the other end to a tire connector mounted on the passage socket. The passage socket is sealed rotationally movably with respect to an adjacent inner side of the axle housing such that an enclosed chamber is formed between the pressure connector and the compressed air duct.

A load based tire pressure regulation system for trucks or trailers employing an air spring maintained at a variable pressure P.sub.AS depending upon the load on the truck or trailer, includes an air pilot pressure regulator receiving air at pressure P.sub.AS and air at the pressure of at least one tire of a truck or trailer, and configured to feed air to and bleed air from the at least one tire of the truck or trailer as a function of the load on the truck or trailer. The pressure regulator is configured to feed air to and bleed air from the at least one tire of the truck or trailer based upon the pressure of the air spring P.sub.AS as a function of the load on the air spring (F.sub.AS), and further upon the recommended pressure P.sub.T of the at least one tire as a function of the load on the tire (F.sub.T).

A rotary feedthrough assembly for a tire inflation system for a vehicle. The assembly may have a stationary part including a first section of a main fluid line and a first section of a pilot fluid line. A rotatable part may be rotatably mounted on the stationary part support a pneumatic tire. The rotatable part may have a second section of the main fluid line and a second section of the pilot fluid line. A first annular seal chamber may be radially disposed between the stationary part and the rotatable part. The first annular seal chamber may provide fluid communication between the first section of the main fluid line and the second section of the main fluid line. A second annular seal chamber may be radially disposed between the stationary part and the rotatable part. The second annular seal chamber may provide fluid communication between the first section of the pilot fluid line and the second section of the pilot fluid line.

A rotary transmission leadthrough is part of a tire pressure control system for a tire of a vehicle, the tire having a hub mounted in a rotatable manner on an axle, the rotary leadthrough having a stator unit mounted on the axle of the tire in such a manner that its position in the axial direction is adjustable relative to the axle. The stator unit has a disc like end member and a bearing member extending in the axial direction from the end member with a bearing surface on its outer radial surface, the end member projecting outwards in a radial direction from the bearing surface. The bearing member retains an inner bearing shell of a rolling bearing carrying the hub. A connector is mounted on the end member connected to an air supply of the tire pressure control system, and an air conduit connecting the connector with an air passage extending in the axial direction under the bearing surface. An opening in the bearing surface connects to the air passage with an air chamber arranged radially to the outside of the bearing surface. A rotor unit connects to the hub in a torque fit manner, and the rotary unit is arranged radially outside to the bearing member of the stator unit and has a connector in a radial outside position connected to the tire valve of a tire mounted on the hub. An air conduit connecting the connector with the air chamber is arranged between the rotary unit and the bearing member; and a sealing unit is arranged between the bearing surface of the stator unit and the rotary unit having at least two sealing rings held in place and arranged with a spacing between them in the axial direction, the spacing defining the air chamber.

A hub cap assembly with a retaining device (100), and at least one housing portion (34) with an annular recess (98) in an inner surface with a sight glass (12) disposed in the annular recess and positioned axially between the retaining device and the housing portion. The hub cap assembly can be part of a wheel end assembly for use with a central tire inflation system (CTIS).