| 摘要 |
PROBLEM TO BE SOLVED: To reduce the size of an electromagnetic actuator mounted in a digital camera and to ensure sufficient driving torque and magnetic attraction force (retaining force). SOLUTION: This device includes a rotor 41 which can rotate within a predetermined angle range, a coil 43, and a yoke 42 having arc surfaces 42a', 42b' facing an outer-periphery surface of the rotor and having a first pole portion 42a and a second pole portion 42b in which mutually different poles are generated by exciting the coil. The rotor 41 includes a magnetized rotor portion 41a magnetized with different poles in a circumferential direction, a driving pin 41b not magnetized and formed so as to rotate integrally with the magnetized rotor portion 41a, and a projection portion 41c projecting from the outer-periphery surface in a radial direction, magnetized with an identical pole with the outer-periphery surface, and formed so as to face the first pole portion or the second pole portion. With this constitution, the total surface of the rotor facing the yoke is increased, thus obtaining a desired retaining force and driving torque while attaining size reduction. COPYRIGHT: (C)2007,JPO&INPIT
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