| 摘要 |
PURPOSE:To detect torque applied to a shaft as variation in the magnetic characteristics of a thin film without contacting by plating the external surface of a metallic sleeve with an amorphous magnetic thin film with nearly the same coefficient of heat expansion. CONSTITUTION:The external surface of the metallic sleeve 30 is plated in a vapor-phase state with the amorphous magnetic thin film 40 to manufacture a strain receiver 20. The thin film 40 is given bias magnetic anisotropy at a constant tilt angle to a peripheral direction by vapor-phase plating in a magnetic field. The body part 31 of the sleeve 30 of the strain receiver 20 has an internal diameter a little bit larger than a shaft 10 and the strain receiver 20 is fitted and fixed to the shaft 10 through a seating part 32. Exciting winding 70 and detection winding 80 are rotationally symmetrical about the shaft 10 and fixed to a fixed ring 90 through a bobbin 50, and they are further mounted on the outer peripheries of both ends of the sleeve through bearings 60. When the torque T is applied to the shaft 10, the magnetic thin film 40 varies in magnetic permeability and variation in the inductance of the winding 80 is outputted to an AC voltmeter 110 as variation in the induced voltage compared with the winding 70, so that the torque T is detected. The torque direction is determined by being compared with the state where there is no torque.
|
