| 摘要 |
PROBLEM TO BE SOLVED: To provide a low-priced actuator suitable for a filter switching device or an iris diaphragm device to be used for a monitoring camera or the like.SOLUTION: In a repeatedly rotating actuator, a two-pole magnetized permanent magnet type rotor 4 having an axis of rotation vertically to an axial center direction of a coil 1 is disposed within the coil 1. Substantially vertically to the axis of rotation and oppositely to an outer peripheral part of the rotor, in an outer circumference of the coil 1, two permanent magnets 7 and 8 of different polarities are disposed at substantially 180° positions. The rotor 4 includes a pair of arms while projecting them in a diameter direction. While the coil is not excited, the magnetic poles of the rotor permanent magnet faces the magnetic poles of different polarities of the two permanent magnets 7 and 8 which are disposed in the outer circumference of the coil. While the coil 1 is electrified, torque is received in the axial center direction of the coil, and the arms of the rotor are mechanically stopped and positioned by stoppers 17 that are provided in a stator, and repeatedly rotated at a finite angle that is determined between the stoppers 17 by switching positive and negative currents.SELECTED DRAWING: Figure 2 |
