| 摘要 |
PROBLEM TO BE SOLVED: To further reduce the size and cost of a lens barrel while ensuring a sufficient speed reduction ratio. SOLUTION: The lens barrel has: a drive motor 111 in which a rotation output shaft 111a is disposed to be substantially parallel to a plane vertical to an optical axis 20a; a first worm 112; a two-step gear 113 in which an intermediate spur gear 113a and a second worm 113b are formed; and a final spur gear 114 in which a rotation center axis is disposed to be substantially parallel to the optical axis 20a. The two-step gear 113 is disposed so that the axial line of the rotation center intersects with a plane vertical to the axial line of the rotation center of the first worm 112, at an angle corresponding to the lead angle of the first worm 112 and the lead angle of the intermediate spur gear 113a (refer to the lower right figure), and also intersects with a plane vertical to the axial line of the rotation center of the final spur gear 114, at an angle corresponding to the lead angle of the second worm 113b and the lead angle of the final spur gear 114 (refer to the intermediate figure). COPYRIGHT: (C)2011,JPO&INPIT
|
