Patent ID: 6397715
Filing Date: 2002-06-04
Classification: B21D,B26D,H01R,Y10S,Y10T

Abstract:
A punch press for cutting and removing at least one dambar from a leadframe of an IC chip package and thereby for separating leads of the IC chip package, comprising:a punch; a punch face at an end of said punch having edges sufficiently sharp to cut through said leadframe of said IC chip package; a dambar die having an opening for receiving said punch when said punch face is forcibly thrust downward against and through said leadframe when said leadframe is positioned between said punch and said dambar die, with the cross-sectional area of said opening sized to conform with said punch face; and a die face at a surface of said dambar die essentially parallel to said punch face, said die face having edges at said opening sufficiently sharp to cut through said leadframe and to remove said dambar therefrom and having one or more irregularities at said edges, said irregularities shaped to form a burr on said dambar cut and removed from said leadframe when said punch face is forcibly thrust downward against and through said leadframe and into said opening, wherein the one or more irregularities are V-shaped grooves cut into the die face and extending essentially perpendicular to a direction of movement of the punch.