Patent ID: 7850678

Claim:
An endoscope for applying a propulsion force in a direction of insertion axis of an insertion portion in accordance with rotation of the insertion portion around the insertion axis based on a driving force of a driving member, the endoscope comprising: a flexible elongated inner layer tube in which bending operation wires for bending a bending portion provided in the insertion portion, a signal cable of an image-pickup unit provided in the insertion portion, a power source cable for a light source provided in the insertion portion, and tubes for air feeding, water feeding and suction provided at the insertion portion are inserted, and which protects the wires, the cable and the tubes for air feeding, water feeding and suction configured as a shaft of the insertion portion; a spiral-shaped portion rotatable around the inner layer tube as an axial center based on the driving force of the driving member, the spiral-shaped portion forming an outer surface of the insertion portion, and covering an outer circumference of the inner layer tube such that a clearance is formed between the spiral-shaped portion and the inner layer tube; and a connection element having a first portion disposed on the flexible elongated inner layer tube and a second portion disposed on the spiral-shaped portion, the second portion being rotatably engaged with the first portion; wherein, the spiral-shaped portion includes a nondensely wound metal coil and a resin thin film continuously provided so as to cover gaps of a wire forming the metal coil.