| 摘要 |
<p>PROBLEM TO BE SOLVED: To miniaturize a motor and to provide it with simple constitution. SOLUTION: This device has a drive shaft 10, a ball screw nut 31 forming a ball screw mechanism 32, a plural number of planetary gears axially supported on the ball screw nut, a brushless motor 4 a rotor 4c of which is a magnet material and a ring gear 27a integrally molding a motor bearing 26. Consequently, a plural number of the planetary gears 28 are engaged with a sun gear 4ca and a ring gear 27a integrated with the rotor, and rotation of the sun gear 4ca is converted to reciprocal motion of the drive shaft 10 by the ball screw mechanism 32 through the planetary gears 28 and the ball screw nut 31.</p> |
