| 摘要 |
PURPOSE:To elevate the ability of detecting precise frequencies per one rotation and productivity for a speed generatr by a method wherein a magnetic circuit is constituted being able to utilize the magnetic flux of efficiently. CONSTITUTION:A magnet 11 is magnetized to form N, S poles in the direction of axis, and a yoke 2, a rotating part 7 and a stationary part 8 constitute a magnetic path confronting teeth at gaps in the middle. When the rotating part 7 rotates, each top of tooth TS of the stator and top of confronting tooth TR of the rotor, top of tooth and bottom of confronting tooth, come to confront alternately making variation in magnetic flux passing the magnetic path, and a speed signal having the same frequency with a number of teeth n is generated in a coil 5. As the magnet 11 has merely a pair of pole N, S, unevenness does not arise in magnetization, and enough quantity of flux can be obtained irrelevant to detecting frequency. Therefor the amplitude of output signal can be magnified by regulating the turn numbers of the speed signal detecting coil 5 wound around a bobbin 4. Each tooth part is processed highly precisely by press blanking process. By this way, a generator having good performance in frequency detection and high productivity can be obtained. |
