Patent ID: 8092371

Claim:
A medical treatment endoscope comprising: a sheath having a flexibility; an arm member having a bending part that projects out from a front end of the sheath and performs bending actions; an advance/retract mechanism which advances and retracts the arm member with respect to the sheath; an open/close mechanism which directs the arm member from a direction along a central axis of the sheath to a rotational direction deviated from the central axis of the sheath around a base axis of the arm member, and from the rotational direction deviated from the central axis of the sheath around the base axis of the arm member to a direction along the central axis of the sheath; and a viewing device and an illuminating member that are disposed to the front end side of the sheath; and an operating member that is inserted in a freely advancing and retracting manner into the sheath; wherein the advance/retract mechanism includes: a guide part that is fixed to the distal end of the sheath; a slide part that is capable of advancing and retracting with respect to the sheath and the guide part, is restricted in an amount of movement thereof with respect to the guide part to predetermined limits, and is capable of protruding from a distal end of the sheath and the guide part in the direction of the arm member advancing/retracting; and the open/close mechanism includes: a first linking part and a second linking part, for converting the advance/retract mechanism of the operating member into the open/close mechanism due to the operating member advancing and retracting, wherein a distal end of the first linking part is connected to the arm member and the other end thereof is connected to the slide part, and a distal end of the second linking part is fixed to another arm member and the other end thereof is fixed to the guide part.