Patent ID: 8362720

Claim:
A linear motor position detection system comprising: a linear motor having one of a mover and a stator in which magnetic poles of N pole and S pole are arranged alternately in an axial direction and an other of the mover and the stator including a plurality of coils and provided for obtaining thrust for linear movement by a magnetic field generated by one of the mover and stator and current passing through the coils of the other of the mover and stator; a magnetic sensor having a magneto-resistive element of which a resistance varies depending on a direction of the magnetic field and provided for outputting a sine wave signal and a cosine wave signal which are 90° phase shifted to each other, depending on change in direction of the magnetic field generated by the linear movement of the mover relative to the stator; and a position detecting circuit for detecting a position of the mover relative to the stator based on the sine wave signal and the cosine wave signal, wherein the magnets sensor is disposed at a position where a magnetic field magnitude, greater than that in a saturation sensitivity range, is applied, the saturation sensitivity range being such that resistance change of the magneto-resistive element is saturated.