Processing method

Abstract

To locally heat only a trim edge. A processing method includes: punching a steel plate; and heating an end face of a heating coil by disposing the heating coil in a non-contact manner along an end surface of a trim edge of the steel plate formed in the punching and perpendicular to a plate thickness direction of the steel plate and applying a current through the heating coil to cause an induced electromotive force on the steel plate. The heating coil is configured by winding a coil wire spirally at least one time.

What is claimed is: 
     
         1 . A processing method, comprising:
 punching a steel plate; and   heating an end face of a heating coil by disposing the heating coil in a non-contact manner along an end surface of a trim edge of the steel plate formed in the punching and perpendicular to a plate thickness direction of the steel plate and applying a current through the heating coil to cause an induced electromotive force on the steel plate,   wherein the heating coil is configured by winding a coil wire spirally at least one time.   
     
     
         2 . The processing method according to  claim 1 , wherein a distance between the heating coil and the steel plate is smaller than a diameter of the coil wire. 
     
     
         3 . The processing method according to  claim 1 , wherein the diameter of the coil wire of the heating coil is larger than the thickness of the steel plate. 
     
     
         4 . The processing method according to  claim 1 , wherein
 a hole is formed in the steel plate by punching the steel plate in the punching, and   a winding start position of the heating coil and a winding end position of the heating coil are located on a line passing through a center of the hole and on the same side with respect to the center.   
     
     
         5 . The processing method according to  claim 1 , wherein
 a hole is formed in the steel plate by punching the steel plate in the punching, and   an outer diameter of the heating coil is larger than a diameter of the hole of the steel plate.