| 摘要 |
PURPOSE:To enable the electric power conservation and the miniaturization of a motor for the direct-coupled driven type rotary magnetic head drum by a method wherein the coil of motor is divided into a speed-detecting coil and each plase coil for stator, and plural position detecting hole elements are so equipped as to locate in the circumferential direction of coil. CONSTITUTION:Coils 12 consisted of a speed-detecting coil 12a and stator coils 12b-12d is attached to a soft ferrite 11 adhered to a stator bracket 9 fixed to a stationary cylinder 2, and position detecting hole elements 13 are so equipped to an under base plate 14 prepared on the stationary cylinder 2 as to be located in the circumferential direction of coil 12. By this way, utilizing the stator bracket 9, as the soft ferrite 11 is adhered to its side face facing a rotary magnet 23 to be used as a stator yoke, current is reduced, and by the application of the speed- detecting coil 12a and the position detecting hole elements 13, the miniaturization of motor can be obtained. |
