| 摘要 |
PROBLEM TO BE SOLVED: To provide a lens barrel capable of improving the design flexibility of a cam groove.SOLUTION: A lens barrel 20 comprises a cylindrical fixed frame 100, a cylindrical first rectilinear frame 110, a cylindrical first rotary frame 210, and a cylindrical second rectilinear frame 120. The fixed frame 100 includes a rectilinear groove a1 and a cam groove b1 in its inner peripheral surface 100S. The first rectilinear frame 110 is disposed radially inside the fixed frame 100 and includes a rectilinear protrusion A1 engaged with the rectilinear groove a1 in its outer peripheral surface 110T and a rectilinear groove a2 in its inner peripheral surface 110S. The first rotary frame 210 is disposed radially inside the first rectilinear frame 110 and includes, in its outer peripheral surface 210T, a cam follower B1 engaged with the cam groove b1 and a cam groove b2 penetrating from its inner peripheral surface 210S to the outer peripheral surface 210T. The second rectilinear frame 120 is disposed radially inside the first rotary frame 210 and includes, in its outer peripheral surface 120T, a rectilinear cam follower AB2 engaged with the rectilinear groove a2 via the cam groove b2. |
