Patent ID: 7469575

Claim:
An engine assembly, comprising: an engine body; an engine component which is configured to rotate relative to the engine body; and a sensing apparatus configured to sense rotation of the engine component relative to the engine body, the sensing apparatus including: a sensor, a bracket configured to position the sensor in a fixed location relative to the engine body, and a starter ring having (i) a support portion configured to rotate in tandem with the engine component, (ii) a starter interface mounted to the support portion, the starter interface being configured to receive drive from a starter motor during operation of the starter motor, and (iii) a trigger portion mounted to the support portion, the trigger portion being configured to provide a series of indicators during rotation of the engine component, the series of indicators being readable by the sensor; wherein the support portion of the starter ring is formed substantially of non-magnetic material; wherein the trigger portion of the starter ring includes a pattern of trigger teeth; and wherein each trigger tooth is formed substantially of magnetic material to provide, as the series of indicators, a series of magnetic field perturbations during rotation of the engine component.