| 摘要 |
PROBLEM TO BE SOLVED: To provide a revolution sensor in which the effective inductance of an exciting coil is uniform along the circumferential direction irrespective of a change in an ambient temperature. SOLUTION: The revolution sensor is provided with a first rotor attached to a first rotating shaft, a fixed core 12 which is fixed to a fixation member and which comprises the exciting coil 12b, a second rotor which is adjacent to the first rotor, which is attached to a second shaft relatively turned with reference to the first shaft and which is arranged between the first rotor and the fixed core 12 and an oscillation means which is connected to the exciting coil 12b and which oscillates an oscillation signal at a specific frequency. The fixed core 12 is covered with a case 12c, whose outer circumference is composed of a conductive member, via a nonmagnetic insulating layer 12g between itself and a core body 12a. |
