Method and system for detecting an axial position of a shaft

摘要

A shaft (28) comprises a hardened outer metallic layer (26) having a first hardness level with a generally uniform radial depth. A first strip (91) extends in a generally longitudinal direction in the outer metallic layer. The first strip (91) has a second hardness level different from the first hardness level. A second strip (93) in the outer metallic layer has the second hardness level. The first strip (91) and the second strip (93) are spaced apart from each other over at least a longitudinal region. A sensor assembly (22) senses a magnetic field. A data processor (82) references an established relationship between a position of the shaft (28) and the angular difference between magnetic fields associated with the first strip (91) and the second strip (93) to detect a position of the shaft (28) with respect to a reference point.