A rotary joint assembly for a tire inflation system includes a rotating portion. The rotating portion is attached to a wheel rim for rotation therewith. The rotating portion includes a center portion which has an air passageway formed therein. The rotary joint assembly also includes a non-rotating portion. The non-rotating portion has a non-rotating portion air passageway formed therein. The non-rotating portion air passageway is in fluid communication with the air passageway formed in the rotating portion via a chamber. A pair of annular sealing members are attached to the rotating portion and sealingly contact a sealing surface of the non-rotating portion. The annular sealing members define an inboard end and an outboard end of the chamber.

An on-board centralized system for regulating pressure of tyres of a vehicle includes a pressurized air source, a circuit communicating the source with a plenum of each wheel, and an arrangement for connecting the plenum of each wheel to the inner chamber of the respective tyre that includes first and second connection lines for deflation and inflation, respectively, of the tyre, and first and second one-way valves interposed, respectively, in the first and second connection lines to allow only a flow of air respectively from and to the inner chamber. The first valve includes a spring having a pre-set load so as to isolate the inner chamber from a part of the circuit upstream of the first valve when said upstream part is at atmospheric pressure, and to guarantee a pre-set minimum value of pressure in the inner chamber when the upstream part is at a pressure lower than atmospheric pressure.

A tyre inflation pressure control system including a vehicle wheel having a tyre interior providing a first fluid chamber and an air reservoir providing a second fluid chamber. A first valve arrangement is installed remote from the wheel and is connectable to a pressurised fluid source. A second valve arrangement, suitably mounted on the wheel, is connected to the first valve arrangement by means of first and second fluid connections. The second valve arrangement is controllably operable to connect the first fluid connection to either fluid chamber. Controlled variation of fluid pressure in and between the fluid connections is provided by the first valve arrangement to control said second valve arrangement for operating the tyre pressure control system to connect the second fluid chamber to the first valve arrangement, and to connect the first and second fluid chambers.

The invention provides an automatic constant pressure device for a hub tire system. The device comprises a valve nozzle, air pipes, valves, a pneumatic slip ring, a hub, a pressure relief valve, a tire, a main shaft, an air storage tank, a vehicle-mounted air source and the like. Two valve holes are machined in the hub of the device. The valve nozzle with a tire pressure sensor is installed at one valve hole, and the pressure relief valve is installed at the other valve hole. The tire pressure is detected by the tire pressure sensor. The valve is controlled to inflate through the valve nozzle, and the pressure relief valve is controlled to relieve the pressure. The device has the characteristics of scientific detection principle, simple and reasonable structure and the like.

A tire deflation and inflation system for a vehicle. The system includes a unit bearing having a plurality of wheel flanges for mounting a wheel thereto. The unit bearing is configured to receive therein a portion of an axle of the vehicle. A wheel hub is mounted to the unit bearing. An air chamber is defined by the unit bearing. In response to positive air pressure generated by an air pressure source, air flows through the air chamber to a tire of the wheel mounted to the unit bearing to increase air pressure of the tire. In response to negative air pressure generated by venting the system to atmosphere, air is drawn out of the tire through the air chamber.

A tire inflation viewing device that enables to view the proper operation of the inflation arrangements and that, in turn, enables to determine which of all of the tires is being inflated and has an air leak.

A valve assembly system including a supply valve assembly, a control valve assembly and a connecting module and the tire pressure management system made therewith.

An on-board centralized system for regulating pressure of tyres of a vehicle includes a pressurized air source, two pneumatic rotary joints each associated to a driving wheel of the vehicle, and a circuit that sets in communication the pressurized air source with each rotary joint. An output member of a constant-velocity joint and a wheel spindle have an internal duct for air passage, connected to the respective rotary joint and to a plenum of the respective driving wheel. Each non-driving wheel has its wheel spindle traversed by an axial bore for air passage, connected to the circuit via a pneumatic rotary joint and a plenum of the non-driving wheel, which is connected to the inner chamber of the tyre. Each driving or non-driving wheel has its plenum connected to the inner chamber via two parallel lines, for deflating and inflating, respectively, the tyre interposed in which are respective one-way valves.

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 wheel end assembly having a spindle, a hub, and a rotary seal assembly. The spindle may have a spindle air passage. The hub may have a hub air passage and an annular hub chamber that may extend around an axis. The rotary seal assembly may fluidly connect the spindle air passage to an inlet of the annular hub chamber.