Self-powered wireless sensor assembly for sensing angular position of the engine crankshaft in a vehicle

摘要

A self-powered, wireless sensor assembly is provided for sensing crankshaft position of an engine comprising a rotatable flywheel having a ring gear. The sensor assembly includes an electromagnetic sensor responsive to structural features on the ring gear when the ring gear rotates. A power supply is coupled to generate a direct current in response to the output signal from the electromagnetic sensor. A transceiver is coupled to one of the following sensors: a magnetostatic sensor energized by the power supply and responsive to the structural features on the ring gear to generate an output signal when the ring gear rotates, and the electromagnetic sensor. The transceiver is configured to wirelessly transmit the output signal from that one sensor, wherein the output signal from that one sensor comprises information indicative of the instantaneous speed of said engine.