| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce the number of magnetic field detection parts and to accurately count a rotational speed and a rounding frequency even when detection pulse omission occurs.SOLUTION: Magnets 51 to 54 are arranged at a movable part 43 rotated with an object to be detected. Magnetic sensors 61 to 63 are arranged on the outer peripheral side of the movable part 43 to output detection pulses by a large Barkhausen effect. The arrangement of the magnets 51 to 54 and the magnetic sensors 61 to 63 is set to satisfy a condition that with points for reversing the magnetizing direction of the magnetic sensors 61 to 63 while the movable part 43 rotated right set as right-rotation reaction points R1, R2, R3, and R4, when one of the magnetic sensors 61 to 63 faces one of the right-rotation reaction points, the others of the magnetic sensors 61 to 63 do not face any of the right-rotation reaction points.</p> |
