Patent ID: 6409658
Filing Date: 2002-06-25
Classification: A61B

Abstract:
An endoscope with an objective lens drive mechanism, comprising:an optical objective lens system incorporated into a rigid tip end section connected to a distal end of an elongated flexible body of an insertion instrument of said endoscope through an angularly bendable angle section and having a fixed lens mounted on a fixed lens frame provided within said rigid tip end section and a movable lens mounted on a movable lens frame for sliding movement in a direction toward and away from said fixed lens along inner surfaces of said fixed lens frame; guide surfaces formed on an inner periphery of said fixed lens frame for guiding sliding movements of said movable lens frame in alignment with an optical axis of said objective lens system; a rotational drive shaft for reciprocating said movable lens frame back and forth in the direction of the optical axis of said objective lens system; an arm portion extended out from said movable lens frame in a radially outward direction substantially perpendicularly to said optical axis of said objective lens system for engagement with said rotational drive shaft; a bearing member provided on said fixed lens frame and adapted to support said rotational drive shaft rotatably relative to said fixed lens frame but to block movements of said rotational drive shaft in an axial direction; a control cable including a flexible transmission shaft connected between said rotational drive shaft and a rotational drive means to transmit rotation from said rotational drive means to said rotational drive shaft, and sheathed in a fixed sleeve having a fore end thereof securely fixed to said bearing member; and a plurality of stopper members provided on said rotational drive shaft to delimit forward and rearward stroke end positions of said movable lens frame.