| 摘要 |
PURPOSE:To eliminate cogging and to reduce uneven rotation by arranging a single, uniformly wound coreless coil and by rotating a rotor made of permanent magnet according to the change of electric current flowing through the coil. CONSTITUTION:A magnetic flux by the permanent magnet of a rotor 1 passes through a magnetic circuit formed by a yoke 7 and crosses a coreless coil 9 existing between the rotor and yoke. Electric current flowing through the coreless coil 9 suitably changes its direction according to the position of the magnetic poles of the rotor 1 to form a rotating magnetic field and rotates the rotor 1 and a shaft 2 so that a torque is outputted. Because the yoke 6 is formed into an integral body over its whole periphery and the coreless coil 9 has no core, a magnetic resistance is prevented from changing according to the angle of rotation so that no cogging occurs consequently. Also, because the coreless coil 9 is uniformly wound continuously round only one spool 10, uneven rotation occurs scarcely. |
