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 tire pressure control arrangement for a vehicle having at least two tires connected to an air supply. Each tire is connected to the air supply via a supply line having a first valve connected to a second valve. The arrangement further includes a pressure sensor between the two valves. The first valve is closed while the supply line is connected to a pressure supply and the pressure in the supply line is monitored for a pre-determined period of time by a control system on the vehicle to detect whether there are any leaks in the arrangement.

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.

The invention relates to a rotary transmission apparatus (1) for the transmission of control and/or working pressures to a fluid duct (51) which is received or configured at least in regions in the interior of a shaft (50), in particular a drive shaft. The rotary transmission apparatus (1) has a stator assembly (2) which is arranged in a stationary manner with respect to a rotational movement of the shaft (50) and has at least one fluid feed/discharge line (3) and a control element (4) which can be displaced in the shaft longitudinal direction (L) relative to the shaft (50) between a first position and a second position. A flow connection between the at least one fluid feed/discharge line (3) and the fluid duct (51) is interrupted in the first position of the control element (4), and a flow connection between the at least one fluid feed/discharge line (3) and the fluid duct (51) is established in the second position of the control element (4).

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 feed-through, designed to transfer a fluid between two entities in rotary motion with respect to one another. The rotary feed-through includes an inner cylindrical ring and an outer cylindrical ring, which are free to turn with respect to one another and provided with channels for passage of the fluid. The channels are connected via at least one annular space axially delimited by seal rings housed in a cylindrical seat. The cylindrical seat faces radially outwards or inwards and is axially delimited, on one side, by an axial abutment of the inner and outer cylindrical rings and, on the other side, by an axial abutment of a lid, a closing ring, or an intermediate ring. The seal rings are interference fitted to the inner or outer cylindrical ring and provided with an elastic portion for contact with the surface of the inner or outer cylindrical ring.

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 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 rotary joint is configured to transfer a fluid between two entities, one of which is in rotary motion with respect to the other. The rotary joint comprises a cylindrical internal element, apt to be fixed to the entity in rotary motion, and a plurality of annular external elements. The external elements comprise at least two head elements, at least two housing elements of respective gaskets, two bearing elements, and at least one fluid inlet. The fluid inlet is placed between said two bearing elements. Housing elements of respective gaskets are arranged externally to the bearing elements, and head elements are arranged externally to the housing elements. The gaskets define an annular shaped sealed area. The sealed area is accessible on one side through said fluid inlet and on the other side through at least one fluid passage channel passing through the body of said internal element.