Abstract: A system for monitoring tire pressure and producing a first signal in the event that a low tire pressure condition has been sensed and a second, different signal in the event that a low tire pressure condition has not been sensed and a third signal in the event that the system is not operable. The system comprises a sensor for each tire and an associated transceiver antenna coil. Each sensor comprises a pressure switch and a circuit that has a first resonant frequency when the pressure switch is in a first state and a second, different resonant frequency when the switch is in a second state. An excited circuit associated with each transceiver antenna coil generates an AC electromagnetic field across the transceiver antenna coil and a detector circuit is operable to demodulate information communicated passively by the sensor that reflects its resonant frequency.

Abstract: A new transfer case with a new and improved clutch actuator and operator is disclosed. The operator is operably connected to a first element of a ball ramp type transfer case clutch actuator that can be rotated, relative to a second element of the clutch actuator, to effect or release compression in the disk pack of the transfer case clutch. The operator comprises a moving coil linear actuator having a stationary magnet and a coil that is mounted adjacent to the stationary magnet for reciprocating movement which is controlled by controlling the flow of current through the coil. Linear movement of the coil is translated into rotational movement of the first element of the clutch actuator by a connecting rod.

Abstract: An actuator for selectively causing axial compression of friction elements in a clutch is disclosed. The actuator comprises a pair of beveled wedge washers and a bearing race supported between the washers. The race supports conical bearing rollers in a generally radial orientation. An actuator plate is mounted for rotation relative to the bearing race and includes bearing ramp surfaces that are operable to move the conical bearing rollers radially inwardly thereby forcing the washers to move apart axially and to thereby cause compression of and torque transfer through the friction elements. A clutch including the actuator is well suited for inclusion in a transfer case.