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.

1 . A method of making a metallic thin wire comprising steps of: 
 preparing one single metallic thin wire having a predetermined length with a middle portion of said one single metallic thin wire as a fixed portion;    twisting front and rear half portions of said one single metallic thin wire, while at the same time, applying a tensile weight to said front and rear half portions, said front and rear half portions being symmetrically located at both sides of said fixed portion; and    processing said one single metallic thin wire with a heat treatment to remove a residual stress from said one single metallic thin wire.    
   
   
       2 . A method of making a metallic thin wire comprising steps of: 
 preparing one single metallic thin wire having a predetermined length with one end of said one single metallic thin wire as a fixed portion;    primarily twisting said one single metallic thin wire in one direction, and then secondarily twisting said one single metallic thin wire opposite to the direction in which said one single metallic thin wire is primarily twisted, while at the same time, applying a tensile weight to said one single metallic thin wire in the lengthwise direction; and    processing said one single metallic thin wire with a heat treatment to remove a residual stress from said one single metallic thin wire.    
   
   
       3 . The method of making a metallic thin wire according to  claim 2 , wherein said primarily twisting step is an excessive enough to induce slip lines on an outer surface of said one single metallic thin wire.  
   
   
       4 . The method of making a metallic thin wire according to  claim 2 , wherein total turning times of said secondarily twisting step is more than 0.15 times inclusive of that of said primarily twisting step, but less than 1.5 times inclusive of that of said primarily twisting step.  
   
   
       5 . The method of making a metallic thin wire according to  claim 1 , wherein said one single metallic thin wire is divided into a plurality of zones in the lengthwise direction, each of which is twisted in different numbers of turns.  
   
   
       6 . The method of making a metallic thin wire according to  claim 1 , wherein said one single metallic thin wire is divided in the lengthwise direction into a plurality of zones in the lengthwise direction, each of which is processed with said heat treatment in varied degrees.  
   
   
       7 . The method of making a metallic thin wire according to  claim 2 , wherein said primarily twisting step and said secondarily twisting step are combined to form a unitary set, and said unitary set is repeatedly applied to said one single metallic thin wire in a plurality of times.  
   
   
       8 . The method of making a metallic thin wire according to  claim 1 , wherein an outer surface of said one single metallic thin wire is treated with an electrolytic polishing procedure after processed with said heat treatment.  
   
   
       9 . A medical tool which incorporates said metallic thin wire produced by the method according to any of claims  1 - 8 .  
   
   
       10 . The medical tool according to  claim 9 , wherein said metallic thin wire is made of an austenitic stainless steel.  
   
   
       11 . The medical tool according to  claim 10 , wherein said metallic thin wire is applied to at least one member selected from the group consisting of a main wire component, a shaft, a stylus, a pull-wire, a stent and a needle.