INTERCHANGEABLE LENS AND IMAGING DEVICE

PROBLEM TO BE SOLVED: To achieve the improvement of usability without involving a cost increase, or the like. SOLUTION: The interchangeable lens includes: a worm wheel 23a engaged with a worm screw 24; a planetary roller 18 rotated in the direction around an axis orthogonal to an optical axis to a cam member 17, and revolved as the cam member rotates; a first rotating member 20 pressed against the peripheral face of the planetary roller; a first receiving seat 21 receiving the first rotation member on the opposite side of the planetary roller; a second rotation member 26 pressed against the peripheral face of the planetary roller from the opposite side of the first rotation member; and a second receiving seat 27 for receiving the second rotation member on the opposite side of the planetary roller, and regulating the rotation of the second rotation member in the direction around the optical axis during the drive of a drive motor. If the lead angle of the worm screw is represented as α, and a friction coefficient in a contact face between the worm screw and worm wheel is represented as μ, the interchangeable lens satisfies μ cosα>sinα. COPYRIGHT: (C)2011,JPO&INPIT