Wire softening apparatus and wire softening method

Abstract

A softening apparatus includes a cooling liquid reservoir for holding a cooling liquid, a first conducting sheave provided outside of the cooling liquid reservoir for applying a voltage to a wire while guiding the wire, and a second conducting sheave provided in the cooling liquid reservoir for letting a current flow through the wire while guiding the wire as the wire is fed via the first conducting sheave. The softening apparatus is also provided with a liquid level detector for detecting a liquid level of the cooling liquid in the cooling liquid reservoir. A heating path length of the wire between the first conducting sheave and the second conducting sheave is controlled based on a result of detection by the liquid level detector.

1 . A wire softening apparatus, comprising:
 a cooling liquid reservoir configured to hold a cooling liquid;   a first conducting sheave provided outside of the cooling liquid reservoir configured to apply a voltage to a wire while guiding the wire;   a second conducting sheave provided in the cooling liquid reservoir configured to let a current flow through the wire while guiding the wire as the wire is fed via the first conducting sheave;   a liquid level detector configured to detect a liquid level of the cooling liquid in the cooling liquid reservoir; and   a heating path length controller configured to control a heating path length of the wire between the first conducting sheave and the second conducting sheave based on a result of detection by the liquid level detector.   
     
     
         2 . The wire softening apparatus according to  claim 1 , wherein the heating path length controller includes:
 a liquid level adjuster configured to adjust the liquid level of the cooling liquid in the cooling liquid reservoir, and   wherein the adjustment by the liquid level adjuster is controlled based on the result of detection by the liquid level detector to maintain the liquid level of the cooling liquid in the cooling liquid reservoir within a certain range.   
     
     
         3 . The wire softening apparatus according to  claim 1 , wherein the heating path length controller includes:
 a sheave position adjuster configured to adjust the position of the first conducting sheave relative to the second conducting sheave, and wherein the adjustment of the position of the first conducting sheave by the sheave position adjuster is controlled based on the result of detection by the liquid level detector to maintain the distance between the first conducting sheave and the liquid level of the cooling liquid in the cooling liquid reservoir within a certain range.   
     
     
         4 . A method for softening a wire, comprising the steps of:
 (a) feeding the wire from a first conducting sheave provided outside of a cooling liquid reservoir to the first conducting sheave provided in the cooling liquid reservoir while letting a current flow through the wire between the first conducting sheave and the second conducting sheave;   (b) cooling the wire with cooling water in the cooling liquid reservoir; and   (c) controlling a heating path length of the wire between the first conducting sheave and the second conducting sheave based on a fluctuation in a liquid level of the cooling liquid in the cooling liquid reservoir.