Patent ID: 8878523
Filing Date: 2014-11-04
Classification: G01D

Abstract:
1. An inductive detection encoder, comprising: first and second members which are oppositely disposed so as to relatively move in a measurement direction; a transmitting coil formed in the first member; a magnetic flux coupled body which is formed in the second member and coupled with a magnetic field generated by the transmitting coil to generate a track in which the magnetic field is periodically changed in the measurement direction; and a receiving coil formed in the first member and having receiving loops periodically formed along the measurement direction corresponding to the track of the magnetic flux coupled body, at least one of the transmitting coil and the receiving coil having: a specific pattern that impairs the uniformity and periodicity of a pattern; and a dummy pattern formed in a position corresponding to a specific phase relationship of a cycle generated by the track with respect to the specific pattern, and when the wavelength of the receiving coil in the measurement direction is λ, the specific pattern and the dummy pattern are formed to be the same patterns in locations spaced apart from each other by (n+[½])λ (in this case, n is an arbitrary integer).