Gregory A Lang

US Patent:

7041933, May 9, 2006

Filed:

Apr 14, 2003

Appl. No.:

10/413341

Inventors:

Ronald E. Forrester - Florence KY, US
Dwight Evans Kimberlin - Cincinnati OH, US
Gregory J. Lang - Reading OH, US

Assignee:

Meyer Tool, Inc. - Cincinnati OH

International Classification:

B23H 1/00
B23H 9/14

US Classification:

219 6917

Abstract:

A method for forming a complex hole through a wall of a structure. The complex hole has a smaller cross-sectional area within the wall and an outer portion with a larger cross-sectional area adjacent a first surface of the wall. The complex hole further has an inner portion extending between the smaller cross-sectional area and an inlet opening on a second surface of the wall. The method uses an EDM process to automatically first, form an entry hole in the wall extending from the first surface to a first location inside the wall, and second, form the outer portion of the complex hole in a direction moving from the first location inside the wall toward the first surface, and third, form the inner portion of the complex hole.