Patent ID: 7612556

Claim:
A rolling bearing apparatus, comprising: a rolling element formed as an inner ring of a bearing; a non-rolling element disposed concentrically with said rolling element; a rotation detector for outputting an induced voltage produced by an input exciting voltage according to a relative rolling state of said rolling element and said non-rolling element; said rotation detector comprising: a rotor provided as part of said inner ring; a stator provided on said non-rolling element: and an exciting winding and output windings wound to said stator, wherein said output windings output the induced voltage induced according to a gap permeance between said rotor and said stator in response to said exciting voltage inputted to said exciting winding; said stator including a plurality of polar teeth opposing said rolling element, and said exciting winding and output windings being wound to each of said polar teeth of said stator, and said rotor comprising a flat portion on a portion of a circumferential surface of said inner ring which opposes and is sensed by said plurality of polar teeth and is an outer peripheral shoulder of said inner ring.