Patent ID: 8663097

Claim:
An insertion device including an elongated insertion portion to be inserted into a subject, comprising: a linear member inserted into the insertion portion and movable forwards and backwards in an insertion direction of the insertion portion; a plurality of mobile bodies provided in a state of being strung together along the insertion direction on an outer periphery of the linear member, the mobile bodies being movable forwards and backwards in the insertion direction with respect to the linear member; a restricting member fixed with respect to the linear member, the restricting member restricting a movable range of each of the mobile bodies with respect to the linear member, and preventing each of the mobile bodies from falling off from the linear member; and a fixing pin being movable between a first position separated from the plurality of mobile bodies, and a second position at which the fixing pin is fitted in between any two of the mobile bodies adjacent to each other in the insertion direction, and being fixed in position in the insertion direction after being fitted in between the mobile bodies at the second position, the fixing pin being formed such that a diameter of an area to be fitted in between the mobile bodies coincides with the movable range of the mobile bodies.