| 摘要 |
PURPOSE:To obtain a driving device which has large torque and can be contained in a ring-shaped space by making circular-arc-shaped permanent magnet confront a ring-shaped ring formed in ?-shape section in a plane and disposing a yoke to confront the permanent magnet to hold the coil. CONSTITUTION:A wire material is radially continuously wound in upper and lower surfaces to allow the section to become ?-shape, thereby producing a ring-shaped coil 4. Circular-arc-shaped permanent magnets 6a, 6b are confronted in a plane so as to relatively rotate with respect to the coil 4. Then, a yoke 5 is so disposed as to hold the coil 4 at the magnets 6a, 6b, thereby forming a driving device. When the coil 4 is formed, the coil may be formed by winding a wire material around the ring-shaped yoke 5 as a core material. In this manner, the torque of the driving device which is contained in a ring-shaped space such as a diaphragm of a camera can be increased. |
