The cam the zoom lens camera cone null 1st lens group which drives

摘要

PROBLEM TO BE SOLVED: To reduce the size by decreasing the number of components. ;SOLUTION: A 1st group cam 9 and a 2nd group lead groove 13 are formed integrally on the internal-diameter side of a zoom operation ring 4, a 1st group straight-moving guide groove 10 and a 2nd group straight-moving guide groove 12 are formed on a fixed cylinder 3, and a 1st group cam follower 7 formed on the zoom extension cylinder 6 of a 1st group and the straight-moving guide piece 11 of a 2nd group holding frame 2 are engaged with the corresponding cam 9, lead groove 13, and straight-moving guide grooves 10 and 12 to constitute a cam mechanism which converts the movement of the zoom operation ring 4 into the movement of the lens group along the optical axis, thereby manufacturing the lens barrel by using inexpensive two-plain split molds.;COPYRIGHT: (C)1997,JPO