| 摘要 |
PURPOSE:To enable the rotation of a rotor to be exactly detected, by generating the output of the detected pulse of voltage adding up electromotive force induced in each gear winding, from FG coils. CONSTITUTION:A frequency generator 30 is provided with a FG board 34 with FG coils 32 on the surface in a ring shape, and the FG board 34 is fitted and fixed on the surface of a stator 20. The FG coils 32 are formed with gear windings 36 at a given pitch which are arranged along the outer peripheral face of the permanent magnet of a rotor 10. The FG coils 32 are provided so that four gear windings 36 may respectively correspond to each permanent magnet 14 of 8 poles of the rotor 10. The rotor 10 confronts the pitch of the gear windings of the FG coils 32, outside the S pole permanent magnet, and the first FG exciting salient section group 100 is provided, and outside the N pole permanent magnet, the second FG exciting salient section group 200 is provided at a pitch with phase different by 180 deg. to the first FG exciting salient section group 100. |
