Wire loop type instrument for endoscope and method of producing the same

摘要

A wire loop type instrument for an endoscope that uses an elastic wire formed from a stranded wire bent into a U-shape and looped at the rear of the U-shaped bent portion. Each strand of the stranded wire has a non-circular cross-sectional configuration in which the strand is more resistant to bending in other directions than in a direction toward the center of the elastic wire. The stranded wire is formed by twisting together a plurality of strands each having a circular cross-section. The stranded wire is passed through a die with a hole having a smaller diameter than that of the stranded wire, thereby compression-deforming each strand into a non-circular cross-sectional configuration. A composite stranded wire may be used as the elastic wire, which is formed by twisting together a plurality of stranded wires each formed from a plurality of strands twisted together.