Patent ID: 8483555
Filing Date: 2013-07-09
Classification: G03B

Abstract:
1. A lens barrel including: a plurality of lens holding frames configured to respectively hold a plurality of lens groups in order that the lens groups be changed from a collapsed state to a photographic state by moving the at least some of the lens groups toward an object, the collapsed state being that in which the lens groups are stored with at least some of the plurality of lens groups retracted; a movable lens barrel configured to hold the lens holding frames in its inside; and a fixed barrel portion configured to hold the movable lens barrel in its inside, the movable lens barrel including a rotary barrel fitted in the fixed barrel portion in a way that makes the rotary barrel movable in a direction of a photographic optical axis with respect to the fixed barrel portion, and revolvable around the photographic optical axis, the lens barrel comprising: a ring member capable of revolving with respect to the fixed barrel portion, concurrently capable of moving in the direction of the photographic optical axis integrally with the rotary barrel, and shaped like a ring which enables the ring member to be accommodated in an inside of the fixed barrel portion, wherein the ring member includes at least one protrusion which projects in a radial direction, the fixed barrel portion includes an engagement section and a rotary drive mechanism, the protrusion being capable of engaging with the engagement section in the direction of the photographic optical axis from near the object, the rotary drive mechanism being configured to make the ring member revolve with respect to the fixed barrel portion in response to the revolution of the rotary barrel with respect to the fixed barrel portion, the rotary drive mechanism makes the ring member assume its rotary posture with respect to the fixed barrel portion in an engagement-enabling position which makes the protrusion and the engagement section opposed to each other in the direction of the photographic optical axis with the protrusion being situated closer to the object, when the connection by the cam mechanism becomes situated in a predetermined position which directs the connection from a first end to a second end of the idle revolving area, the first end continuing to the advancement/retreat movement area, the rotary drive mechanism makes the ring member assume its rotary posture in a release position which releases the engagement section and the protrusion from their opposed state in the direction of the photographic optical axis, when the connection by the cam mechanism becomes situated in a location of the first end of the idle revolving area, and the rotary drive mechanism makes the ring member keep its rotary posture in the engagement-enabling position, when the connection by the cam mechanism becomes situated in a position between the predetermined position and the second end.