| 摘要 |
PROBLEM TO BE SOLVED: To provide an actuator which need not a lubricating oil for its feed screw, can establish reduced dust, etc., and less noise emission, and can transport works, etc., stably. SOLUTION: A feed screw 36 is provided with spiral male threads 58a and 58b in double start form, and magnetic poles 60a and 60b are formed at the crests of these male threads 58a and 58b, while magnetic poles 62a and 62b are formed at the bottoms. Female threads 68a and 68b are formed in a displacing member 66, and magnetic poles 70a and 70b are formed at the bottoms of the female threads 68a and 68b, while magnetic poles 72a and 72b are formed at the crests. According to this configuration, the magnetic poles 60a, 60b, 62a, 62b on the feed screw 36 make repulsion to the magnetic poles 70a, 70b, 72a, 72b on the displacing member 66 so that the feed screw 36 and displacing member 66 are held without contact.
|
