STEPPING MOTOR

PURPOSE:To enable improvement of accuracy is assembly and the miniaturization by press stamping the pole tooth for the first phase and the pole tooth for the second phase into specified shapes out of a specified plate member by press processing, and then, bending them into cylindrical shape thereby uniting them. CONSTITUTION:For inner pole teeth 25, pole teeth 25A for A phases and pole teeth 25B for B phases are made to project in the shapes of trapezoid at both ends by press stamping a plate member 23 of iron material. Furthermore, the plate member 23 is bent into cylindrical shape, and then, the junction ends 25C and 25D are joined together, thus the pole teeth 25A and B for A phases and pole teeth 25B for B phases are made at the ends of both openings 26A and 26B of the cylinder. And the pole teeth 25A and 25B are positioned where the phases are shifted by the amount of a specified angle alpha each as an electric angle where one set of an S pole and an N pole of a rotor magnet is 360 deg., but the accuracy of the phase difference between pole teeth 25A and 25B is materialized by the accuracy in the stamping process by a press. Accordingly, a stepping motor can be gotten, wherein the phase difference between A phase and B phase can be improved exceptionally and the diameter becomes small.