Rotary seal systems and apparatus communicate a working fluid between first and second associated machine components that are rotatable relative to each other. A rotary seal apparatus includes annular inner and outer sleeve members for engaging the associated machine components, and a sealing system disposed between the inner and outer sleeve members. The sleeve members each define respective passageways extending through sleeve bodies thereof, and the sealing system forms a fluid chamber between the sleeve bodies defining an annular fluid channel operable to communicate the working fluid between fluid ports of the associated machine components via the passageways of the sleeve members. The rotary seal system may be provided in combination with an axle having a radial passageway opening outside of axially spaced apart first and second bearings carrying the axle.

An inflation viewing device has a main body which is externally provided with a transparent viewing portion and internally provided with an inner passage where an air path assembly is arranged. An air entrance connector is operatively connected to an external air source and to a first end of the main body. An air exit connector is connected to a second, opposed end of the main body and to an inflation valve. A guide spacer is provided between the air entrance connector and the main body. The guide spacer has an inner passage having a wider section in communication with the inner passage of the main body and a reduced section defining a communication opening with the air entrance connector. A filter is arranged in the communication opening. A plunger, biased by a spring, is slidably arranged within the inner passage of the guide spacer and guide section of the main body inner passage.

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.

A rotary union having a housing, a shaft rotatably disposed within the housing, and a tube having a first end sealingly disposed within the shaft and a second end sealingly coupled to the housing. A tire inflation system may comprise a rotary union externally mounted to a vehicle wheel end or mounted to a vehicle fairing.

A tire inflation system includes a first component rotating relative to a second component, a first passageway between the first and second components, the first passageway connecting a pressure source to a pressure consumer, a first seal in contact with an interface between the first and second components, the first seal maintaining pressurized fluid in the first passageway, a second seal in contact with the interface between the first and second components, the second seal spaced apart from the first seal forming a first chamber, a third seal in contact with the interface between the first and second components, the third seal spaced apart from the second seal forming a separate second chamber, and a second passageway connected to the separate second chamber and to the atmosphere.

A compact rotary union assembly for inflating and deflating a tire mounted to a hub having a hub housing. The compact rotary union assembly includes a spindle, an inner sleeve, and an outer sleeve. The spindle includes a spindle channel. The inner sleeve includes a flange portion, a cylinder portion coupled to the flange portion, a bore extending through the flange portion and the cylinder portion, and an inner sleeve channel located within the flange portion and the cylinder portion. The inner sleeve channel is coupled to a first port and to the spindle channel. An outer sleeve includes an outer sleeve channel, coupled to the spindle channel and to a second port, wherein the cylinder portion is located within an outer sleeve bore of the outer sleeve. A first and a second air seal are located within the outer sleeve on either side of an air track.

An axle assembly includes a first axle shaft. The first axle shaft includes a first conduit. A second axle shaft includes a second conduit. The first conduit and the second conduit are in fluid communication through a chamber. A differential is operatively connected to the first axle shaft and the second axle shaft. The chamber is at least partially disposed within the differential.

An air inflation system is provided for a vehicle including an axle that supports a wheel and an air supply structure. The air inflation system includes a rotary coupler having a tubular member for communicating with the air supply, a sleeve member connected to an end portion of the tubular member, a bearing receiving the sleeve member, a housing body having a passageway therethrough, wherein the tubular member is received in the passageway, and a housing cap attached to the housing body, wherein the housing cap is provided for communicating with at least one air connection element in communication with the wheel. A first seal for sealing an area between the tubular member and the housing body, and a second seal for sealing an area between the housing body and the housing cap are included. The rotary coupler is provided for supplying air from the air supply to the wheel.

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.

A rotary joint assembly for a tire inflation system for a vehicle includes a stationary portion defining a first fluid passage. The stationary portion includes a support portion and having a first annular sealing face. The first fluid passage ending in the first annular sealing face. The assembly also includes at least one bearing and a rotatable portion rotatably mounted on the support portion by way of the at least one bearing. The rotatable portion defines a second fluid passage and has a second annular sealing face, the second fluid passage ending in the second annular sealing face. The rotatable portion defines an axis of rotation of the rotatable portion and a radial direction oriented perpendicular to the axis of rotation. The at least one bearing supporting an inner face of the rotatable portion, wherein the inner face of the rotatable portion faces toward the axis of rotation. An annular seal chamber is radially disposed between the first annular sealing face and the second annular sealing face and provides fluid communication between the first fluid passage and the second fluid passage. The at least one bearing and the annular seal chamber at least partially overlap along an axial direction oriented in parallel to the axis of rotation.