Lens barrel

摘要

At an inner circumferential surface of a cam frame, second cam grooves and an inner gear are formed. A second lens group frame includes a base, extensions each extending from the base in an optical axis direction, and cam pins each outwardly protruding from a tip end part of a corresponding one of the extensions in a radial direction. In the extension, a stepped part is formed. The stepped part overlaps, when each cam pin moves according to a corresponding one of the second cam grooves, with the inner gear as viewed in the radial direction, and is recessed toward the inside in the radial direction as compared to a tooth tip of the inner gear so as not to overlap with the tooth tip of the inner gear as viewed in a circumferential direction.

主权项

1. A lens barrel in which a lens is movable in an optical axis direction, comprising:
a cylindrical cam frame formed, at an inner circumferential surface thereof, with
a cam groove extending in a predetermined pattern, andan inner gear inwardly protruding in a radial direction and extending in a circumferential direction; and a lens frame including
a base configured to hold the lens inside the cam frame,an extension extending from the base in the optical axis direction, anda cam pin outwardly protruding from a tip end part of the extension in the radial direction and fitted into the cam groove, wherein the extension includes
a first member extending from the base along a first axis which is parallel with the optical axis,a second member disposed along a second axis which is outside of the first axis in the radial direction about the optical axis, extending along the second axis, and configured to hold the cam pin, anda third member connecting between the first and second members, and a stepped part which, when the cam pin moves according to the cam groove, overlaps with the inner gear as viewed in the radial direction and is recessed toward an inside in the radial direction as compared to a tooth tip of the inner gear so as not to contact the inner gear is provided in the extension.