| 摘要 |
PURPOSE:To improve the responsiveness of a stepping motor by shortening the axial length by axially overlapping parts of the projections of adjacent pole plates and equalizing the circular-arc length of a rotor to that of the part overlapped with the projections. CONSTITUTION:A plurality, for example, 4 of pole plates 21-24 are fixed to a hollow stator shaft 1, and four projections 21a-24a whcih are radially projected to the plates 21-24 are formed at every 90 deg.. In this case, the opening angle between the projections 21a and 24a is set to 60 deg., and the opening angle between the projections 22a and 23a is set to 90 deg., and the adjacent projections 21a-24a are disposed axially to be overlapped partly, and the overlapped part is sequentially moved in the rotating direction. A rotor 6 is formed in a ring shape, a window is formed at the rotor 6, thereby forming the pole teeth 6a of the circular-arc length (opening angle of 30 deg.) corresponding to the length of the overlapped part of the projections 21a-24a are formed at the interval of 90 deg.. Three coils 3, 4, 5 disposed between the pole plates 21-24 are sequentially energized, thereby stepwisely driving the rotor. |
