JPS54120809A - Dc motor - Google Patents

Abstract

PURPOSE: To provide a lower level of electrical noise with a rotating torque obtained without switching the drive current, by such means that, with a field magnet rotated on its own axis in accordance with a rotational position of the rotor, an interlinkage be made between the coil current and the flux through a switching of the magnetic pole at the side of facing the coil.

CONSTITUTION: Magnets M1 to M8, installed in the interior of a rotor 1, rotate with the rotor 1 while making three turns on its own axis in one revolution of said rotor 1 according to the gear ratio. And for instance, the magnet M1 is placed at a position, as shown in the drawing, with the bordering part of its S, N-pole facing the bordering part of the coil forward and return path portion 10a, 11b. Accordingly, in a range of rotating angle of 90° of the rotor 1, the N-pole faces the forward path portion 10a with a torque generated to rotate the rotor 1 in a direction of the arrow mark A, and in a range of rotating angle of 90° to 180°, with the rotor 1 rotated by 90° and a polarity of the magnet M1 inverted, a torque is generated in a similar direction of the arrow mark A. And at a position of rotating angle of 180°, is again inverted the polarity of the magnet M1, thereafter, in the similar way as before, a rotating torque is kept generating in the same direction.

COPYRIGHT: (C)1979,JPO&Japio