Lens-frame moving mechanism

摘要

A lens-frame moving mechanism includes a lens frame guided to move between a ready-to-photograph position and a retracted position, the lens frame being biased forwardly by a biaser; an intermediate linearly movable member, wherein the lens frame contacts the intermediate linearly movable member; a leading screw formed on the drive shaft of a motor; a nut member screw-engaged onto the leading screw, wherein the nut member does not rotate relative to the lens frame and moves the intermediate linearly movable member in the optical axis direction; and a rearwardly-movable member which rearwardly moves the lens frame against the biasing force such that the lens frame moves away from the intermediate linearly movable member in the optical axis direction while the lens frame is moved from the ready-to-photograph position to the retracted position.

主权项

1. A lens-frame moving mechanism, comprising:
a lens frame which holds a lens group and is linearly and slidingly guided by a guide shaft to move, in an optical axis direction of said lens group, between a ready-to-photograph position and a retracted position, said lens frame being biased forwardly in the optical axis direction by a biaser; an intermediate linearly movable member which is linearly guided to move in the optical axis direction, wherein said intermediate linearly movable member is separately movable from said lens frame, and said lens frame that is forwardly biased by said biaser in the optical axis direction contacts said intermediate linearly movable member; a leading screw which is directly formed on a drive shaft of a motor, by which said leading screw is rotated, wherein said drive shaft non-engagingly passes through said intermediate linearly movable member; a nut member which is screw-engaged onto said leading screw, wherein said nut member does not rotate relative to said lens frame and is arranged to move said intermediate linearly movable member in the optical axis direction, and wherein said nut member and said intermediate linearly movable member constantly contact each other; and a rearwardly-movable member which is arranged to rearwardly move said lens frame against said biasing force applied thereto by said biaser such that said lens frame moves away from said intermediate linearly movable member in the optical axis direction while said lens frame is moved from the ready-to-photograph position to the retracted position.