Charles E Frame

US Patent:

50442376, Sep 3, 1991

Filed:

Feb 5, 1990

Appl. No.:

7/474915

Inventors:

Charles Frame - Clementon NJ

Assignee:

Magnetic Metals Corporation - Camden NJ

International Classification:

H02K 1502

US Classification:

83 41

Abstract:

Metal parts requiring sharply-defined, accurate corners are formed in a two-step process. In the first step, first openings are made in a thin sheet of material, at least one edge of the first opening forming one edge of the desired sharply-defined corner. In the second step, a second opening is formed, wherein one edge of the second opening intersects the edge of the first opening at a predetermined angle. A sharp corner is formed at the intersection of these edges. In a preferred embodiment of the invention, the method is used as an improved method of forming single laminae and stacked laminae for stators and rotors of electric motors; in this embodiment a plurality of first openings are made in an annular array.