| 摘要 |
PURPOSE: To provide an inexpensive speed sensor with a small mounting space by simplifying a magnetic circuit, in the speed sensor which detects the speed of the drive shaft moving in a body with the pickup of a linear motor used for a CD-ROM device, etc., with a magnetic circuit and a detection coil, and a linear motor using it. CONSTITUTION: A permanent magnet bar 5, which doubles as a guide shaft in parallel with the center yoke 8 of a drive linear motor 1, is attached, and a detection coil 5 is attached in a body with the drive shaft 14 mounting a pickup 4 driven with a drive coil 7, being wound at a right angle with the longitudinal direction of the permanent magnet bar 5. |
