| 摘要 |
PROBLEM TO BE SOLVED: To provide a magnetic encoder improved in rotation detecting accuracy with regard to a rotary part by reducing a variation in output voltage amplitude of a magnetic sensor, even when the rotary part consisting of a magnetic body is eccentric with respect to a rotational shaft.SOLUTION: A magnetic encoder 1 comprises: a discoid rotary part 4 consisting of a magnetic body and fixed to a rotational shaft 2 so that a flat surface of the rotary part 4 is perpendicular to an axis center of the rotational shaft 2; at least one or more magnetic sensors 6A and 6B arranged in predetermined spaced relation to the rotary part 4; and at least one or more bias magnets 12A and 12B provided for each of the magnetic sensors 6A and 6B. The rotary part 4 includes a plurality of shape changing portions 4a along a circumferential direction of the rotary part 4 that bring about a change in distance to the magnetic sensors 6A and 6B when the rotary part 4 rotates. The magnetic sensors 6A and 6B are arranged on a flat surface which is perpendicular to the axis center of the rotational shaft 2, so as to face the shape changing portions 4a in a plate thickness direction of the rotary part 4. |
