Syuichi Takayama: Endoscope system with an electric bending mechanism. Olympus Optical, February 19, 1985: US04499895 (293 worldwide citation)

An endoscope apparatus is disclosed which includes an insertion section inserted into a coeliac cavity of a human body and freely bendable therein, a motor housed in an operating section of an endoscope, a bending mechanism for bending a flexible tube of the insertion section on the basis of a torqu ...