| 摘要 |
PROBLEM TO BE SOLVED: To realize the improvement of the torque of a drive motor and the miniaturization or the like of an imaging apparatus. SOLUTION: The drive motor is provided with; a magnet 41 formed to be cylindrical, magnetized in a periphery direction and rotated in the periphery direction; a turning arm 42 turned integrally with the magnet and moving movable members 26 and 27 opening/shutting the optical path of an imaging optical system; a stator coil 45 arranged in a coil bobbin 35 so as to surround the magnet from the outside; and a stator yoke 44 arranged outside the coil bobbin and forming a closed magnetic path closed in the rotational direction of the magnet. It is provided with a projecting part 47 projecting inward in the stator yoke and holding a magnetic equilibrium condition between the magnet and the stator yoke during non-energization of the stator coil, and the projecting part is constituted of a 1st part 47a and a 2nd part 47b made continuous so as to come closer as going to the inside. The 1st part is positioned nearer to the edge side in the rotational direction of the magnet during non-energization of the stator coil than the 2nd part, and the tilt angle of the 2nd part to a line segment L extended in a radial direction to the continuous part 47c of the 1st and the 2nd parts from the center of rotation is made smaller than that of the 1st part. COPYRIGHT: (C)2006,JPO&NCIPI
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