Patent ID: 7357164

Claim:
A device for maintaining a desired inflation pressure of an interior of a tire mounted on a wheel of a vehicle, the wheel rotatably connected to a stationary member of a vehicle wheel assembly and defining an axis of rotation, the device comprising: at least one magnetic element mounted on the stationary member at a radial distance from the axis of rotation, the magnetic element producing a magnetic field; an electrical coil mounted on the wheel and radially disposed from the axis of rotation relative to the magnetic element to pass through the magnetic field during each revolution of the wheel, the coil operative to induce electrical voltage pulses in response to transiting the magnetic field and to output the electrical voltage pulses for powering at least a portion of the device; an air compressor mounted on the wheel, the air compressor powered by one of transiting the magnetic field and the electrical voltage pulses induced in the coil, the air compressor in fluid communication with the interior of the tire and operative to output compressed air to the interior of the tire; and means for regulating output pressure of the compressor to the desired inflation pressure without off-wheel aid, wherein the magnetic element is an electromagnet that serves as the primary winding of an intermittent split transformer with the electrical coil forming the secondary winding of the split transformer, the split transformer operative while the primary and secondary windings are in magnetic communication, the split transformer performing at least one of transferring electrical power from the vehicle to the wheel and providing two-way pulse data communication between the vehicle and the wheel.