DH

Douglas J. Hennenfent

MP Magnetic Peripherals: 7 patents #5 of 149Top 4%
CD Control Data: 2 patents #17 of 192Top 9%
📍 Minneapolis, MN: #574 of 6,114 inventorsTop 10%
🗺 Minnesota: #6,858 of 52,454 inventorsTop 15%
Overall (All Time): #474,170 of 4,157,543Top 15%
11
Patents All Time

Issued Patents All Time

Showing 1–11 of 11 patents

Patent #TitleCo-InventorsDate
5580006 Sprocket crusher Lloyd M. Thorndyke 1996-12-03
4942658 Method for manufacturing a magnetic head core with a flux gap having a precisely controlled length Timothy W. Vandnais, Judy M. Ekern 1990-07-24
4874922 Granule vise for manufacturing a magnetic head core with a glass fillet adjacent the inner edge of the gap Timothy W. Vadnais 1989-10-17
4559743 Method for calibrating a machining sensor Alan G. Kracke, Allan L. Holmstrand 1985-12-24
4536992 Precision lapping system Allan L. Holmstrand, Alan G. Kracke 1985-08-27
4517041 Method for attaching a workpiece to a workpiece carrier Allan L. Holmstrand, Alan G. Kracke 1985-05-14
4457114 Workpiece carrier Allan L. Holmstrand, Alan G. Kracke 1984-07-03
4297781 Method of aligning a precision grinding wheel assembly Robert A. Johnson, Allan L. Holmstrand 1981-11-03
4279102 Method of manufacturing narrow track ferrite head cores Robert A. Johnson, Allan L. Holmstrand 1981-07-21
4236355 Precision grinding wheel mount Robert A. Johnson, Allan L. Holmstrand 1980-12-02
4182643 Method of forming gaps in magnetic heads Arthur Calderon, Allan L. Holmstrand 1980-01-08