A wire made up of a plurality of wire strands is wound around a tubular body coupled to a distal end working unit. A fixing pin has a through hole through which the wire is inserted. The fixing pin is fitted into a recess disposed in a side surface of the tubular body. The fixing pin is welded to the tubular body and the wire. The melting point of the wire is higher than the melting point of the fixing pin. In a state where material of the fixing pin flows in between the wire strands, the fixing pin and the wire are joined together.
