A self-inflation device for maintaining pressure in a tire, the self-inflation device includes a body having a piston compartment and an intake opening external to an inner space of the tire and a piston housed in the piston compartment and having a piston opening internal to the inner space. The piston is moved to a pulled position by centrifugal force applied by rotation of the tire to open the intake opening, and moved to a pushed position by air pressure from the inner space to block the intake opening and create a compression chamber within the piston compartment. The self-inflation device further includes a valve separating the compression chamber and the piston opening. The valve is opened when the piston is in the pushed position to allow airflow between the compression chamber and the inner space.

Described are valve stems for wheels or other pressure vessels that may be installed from the exterior of a wheel or pressure vessel without access to the interior, pressure retaining areas. The valve stem may include a body with a barrel and taper. A neck may be between the body and a base that includes a flange, a flange landing, and an air aperture. An air channel runs vertically through the valve stem to allow air to pass from one side of the valve stem to another with a valve core or other flow control device. The base of the valve stem may include a groove that allows the valve stem to be installed into a hole by twisting such that the groove may ride along the rim of the hole and guide the valve stem into a fully seated and sealed position.

A highflow air coupling system is provided. The highflow air coupling system has a valve chamber housing having a plurality of openings including a user serviceable port and a reversible air flow valve. The interior of the valve chamber housing has a multi-tiered main valve with multiple large holes located on multiple levels. A unique exterior grip of the housing allows for easy grasping of the housing chamber. The device and system are especially suitable for use with, for example, inflating tires, especially in a military environment.

A central tire inflation system for maintaining tire inflation on a vehicle is provided. The central tire inflation system includes a rotary union assembly having a housing that is coupled to and rotates with the hubcap. The housing is rotationally coupled to a stationary shaft. A flexible torque transfer shaft is connected to the stationary shaft on one end and to an axle plug on the other end. The axle plug has a hub forming a bore where the hub is movable on a web of material. The flexible torque transfer shaft and hub have cooperative non-circular shapes to resist rotation. An air vent is provided in the rotary union assembly that is isolated from the lubrication area, which inhibits the pressurized air from the central tire inflation system from pressurizing the lubrication area.

A central tire inflation system for maintaining tire inflation on a vehicle is provided. The central tire inflation system includes a rotary union assembly having a housing that is coupled to and rotates with the hubcap. The housing is rotationally coupled to a stationary shaft. A flexible torque transfer shaft is connected to the stationary shaft on one end and to an axle plug on the other end. The axle plug has a hub forming a bore where the hub is movable on a web of material. The flexible torque transfer shaft and hub have cooperative non-circular shapes to resist rotation. An air vent is provided in the rotary union assembly that is isolated from the lubrication area, which inhibits the pressurized air from the central tire inflation system from pressurizing the lubrication area.

A wheel provided with a tire in tire installation in which an outer ground engaging tire is mounted on a rim of the wheel and an inner inflatable member is mounted on the rim inside the outer tire. The inner surface of the outer tire and the outer surface of the inner inflatable member are provided with respective electrically conductive members suitably in the form of induction loops. A controller determines when the respective electrically conductive members come into close proximity or contact, enabling manual or automated adjustment of air pressure to minimize abrasion between the outer tire and inner inflatable member.

An exterior installable air valve for a tire rim using an exterior operated nut compressing a gasket against a wedge to expand the gasket for sealing to a wheel rim.

A coupling for valve assemblies, for tubeless tires, includes an enclosure arranged to cover a rigid rim of a vehicle, to delimit a substantially tubular compartment, filled with gas under pressure. The coupling has a first element and a second element crossed respectively by a first through channel, threaded internally, and by a second through channel. The second element cooperates with a valve for the selective closure of the second channel. The first element rests on an internal surface of the rim, which can be activated following its hermetic insertion, from the inside of the compartment. The second element rests on an external surface of the rim, which can be activated following the hermetic screwing, from the outside of the compartment, of a threaded stem of the second element in the first channel, with consequent alignment between the channels to connect the compartment to the outside.

A pressure equalization valve assembly may include a valve body forming fluid chamber configured to receive pressurized fluid from a fluid pressure source, a first port configured for sealed communication with a first vehicle tire, and a second port configured for sealed communication with a second vehicle tire; a first one-way valve disposed in the valve body between the fluid chamber and the first port so as to allow one-way fluid communication from the fluid chamber to the first port when the first one-way valve opens; a second one-way valve disposed in the valve body between the fluid chamber and the second port so as to allow one-way fluid communication from the fluid chamber to the second port when the second one-way valve opens; and a two-way valve disposed in the valve body between the first port and the second port so as to allow two-way fluid communication between the first port and the second port when the two-way valve opens.

An air maintenance tire assembly includes a tire having a tire cavity bounded by first and second sidewalls extending to a tire tread region, air pumping means for generating pressurized air for maintaining air pressure within the tire cavity at a preset pressure level, the air pumping means including a soft tubing and compression fittings for mitigating dynamic loading on the compression fittings, and a valve housing disposed adjacent an outward end of the valve stem and operative to selectively open and close pressurized air flow from the valve stem internal passageway into the tire cavity. The valve housing is connected to the air pumping means by the soft tubing and compression fittings for mitigating dynamic loading on the compression fittings.