Method of making a metallic thin wire and a medical tool into which the metallic thin wire is incorporated

Abstract

In a method of making a metallic thin wire (1), one single metallic thin wire (2) is prepared to have a predetermined length with a middle portion of the one single metallic thin wire (2) as a fixed portion. Front and rear half portions of the one single metallic thin wire (2) are twisted with the front and rear portions being symmetrically located at both sides of the fixed portion, while at the same time, applying a tensile weight (W) to the front and rear half portions in the lengthwise direction. The one single metallic thin wire (2) is processed with a heat treatment to remove a residual stress from the one single metallic thin wire (2). Otherwise, the front and rear portions of the one single metallic thin wire (2) is primarily and secondarily twisted alternately under the tensile weight (W) applied in the lengthwise direction. This provides the metallic thin wire (1) with a high rotation-following capability and high torque transmissibility, thus enabling artisans to usefully apply the metallic thin wire (1) to a main wire component (25) of a medical tool and equipment.

Description

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The invention relates to a method of making a metallic thin wire in the form of a flexible wire configuration used as a main wire component of a medical tool such as a catheter, a catheter guide wire, an endscope treating instrument or the like, and particularly concerns to a medical tool produced by the method of making the metallic thin wire. [0003] 2. Description of Prior Art [0004] In a catheter and a catheter guide wire which introduces a leading distal end into a diseased area through a sinuous vascular system, the leading distal end of the catheter or the catheter guide wire is inserted into the blood vessel or the somatic cavity by a “push-pull and turn” manipulation at a hand access portion located outside a subject patient upon treating the diseased area. In an endscope treating instrument which is inserted through a somatic cavity to reach the diseased area, a leading end of the endscope treating instrume...

AI Technical Summary

Benefits of technology

[0012] According to the present invention, there is provided a method of making a metallic thin wire which is twisted in one direction under a tensile weight applied in the lengthwise direction, or primarily and secondarily twisted alternately in one direction and the opposite direction under the tensile weight applied in the lengthwise direction. This induces a uniform torsional rigidity in the right and left directions through an entire length of the one single metallic thin wire.

[0013] According to other aspect of the present invention, one single metallic thin wire is prepared to have a predetermined length or a bifold extension of the predetermined length. A middle portion of the one single metallic thin wire is fixedly supported at a fixed portion. Front and rear half portions of the one single metallic thin wire is twisted (in one direction) with the front and rear half portions symmetrically located at both sides of the fixed portion. At the time of twising the front and rear half portions, a tensile weight is concurrently applied to the front and rear half portions. This produces two metallic thin wires simultaneously in a dual-way fashion to maintain the product quality uniform while improving the productivity.

Problems solved by technology

It is, however, poor in torsional characteristics.

This leads to a shortage of the torque transmissibility and rotational maneuverability so as to reduce the steerability.

This makes the catheter guide wire costly and disadvantageous especially when brought to the mass production.

In addition, the metallic thin wire is twisted only in one direction, and thus making the torsional characteristics uneven in the lengthwise direction.

Images