| 摘要 |
PURPOSE:To generate pulses proportional to a rotating speed and detect the rotating speed and an angle accurately by recording magnetically binary information at the circumference of the outer circumferential surface of the magnetic thin film on the surface of a rotary disk alternately on vertical magnetization basis. CONSTITUTION:An input shaft 2 is supported in a bearing 3 fitted and held in cases 12 and 13, and the rotary disk 4 is fitted to the input shaft 2. The magnetic thin film 11 is formed on the surface of the disk 4 and binary information is recorded magnetically and alternately at the circumference of the outer circumferential surface of the thin film 11 on vertical magnetization basis. Then, when the disk 4 rotates, information recorded magnetically by a magnetic head 9 for vertical magnetization response arranged facing the thin film 11 is detected to output an AC signal. The output signal is differential by a control circuit 10 and converted into a speed control signal, which is applied to a servomotor 1 to control the speed, so the resolution is improved; and the need to use a speed reducing gear, etc., in combination is eliminated to attain size reduction. |
