Patent ID: 8181538
Filing Date: 2012-05-22
Classification: B62D,G01L,Y10T

Abstract:
1. A magnestostrictive torque sensor comprising: a rod-shaped rotating shaft; a magnetostrictive film which is formed on a surface of the rotating shaft so as to extend along a full circumference of the surface in a circumferential direction; and a first detection coil, a second detection coil and a third detection coil which are disposed along a circumference of the magnetostrictive film, wherein the magnetostrictive film is formed as an area which extends continuously in an axial direction of the rotating shaft and includes on the continuously formed area a first magnetostrictive film portion and a second magnetostrictive film portion having magnetic anisotropies which are opposite to each other and a third magnetostrictive film portion which is formed between the first magnetostrictive film portion and the second magnetostrictive film portion, and wherein the first detection coil, the second detection coil and the third detection coil are provided so as to correspond to the first magnetostrictive film portion, the second magnetostrictive film portion and the third magnetostrictive film portion, respectively.