David A Paulson

US Patent:

7077799, Jul 18, 2006

Filed:

Nov 28, 2003

Appl. No.:

10/724432

Inventors:

Adelbert Gorham - Burnsville MN, US
Denis J. Dudrey - Bloomington MN, US
James N. Gehrking - Burnsville MN, US
Ronald L. Jorgenson - Apple Valley MN, US
David S. Paulson - Elko MN, US
Rodger I. Spears - Bloomington MN, US
Lloyd E. Weisert - Bloomington MN, US

Assignee:

Advanced Products Laboratories, Inc. - Burnsville MN

International Classification:

B04B 1/06
B04B 11/05

US Classification:

494 37, 494 52, 494 77, 494 84

Abstract:

A self-cleaning centrifuge for clarifying contaminated liquids has a rotor assembly comprising nested first and second sets of concentric cylinders supported for rotation about an axis. The sets of concentric cylinders are rotatably connected. A motor is connected to rotate one of the sets. Contaminated liquid is supplied to the nested cylinders, and the liquid provides coupling between both of the sets so that both sets rotate about the axis. Centrifugal force causes foreign matter to collect on the circumferential surfaces of the cylinders. The resultant clarified liquid is collected for reuse. A selectively utilized brake provides sudden braking of one of the rotating sets to purge collected foreign matter from the cylinders. The purged foreign matter is collected for disposal.

US Patent:

48390372, Jun 13, 1989

Filed:

Apr 6, 1987

Appl. No.:

7/037113

Inventors:

Robert A. Bertelsen - St. Louis Park MN
David J. Paulson - Minnetonka MN

Assignee:

Osmonics, Inc. - Minnetonka MN

International Classification:

B01D 2704
B01D 2906

US Classification:

210 97

Abstract:

A spirally wound filter cartridge and a method of making the same in which the cartridge includes an elongated, centrally disposed tube or mandrel, and a sheet of filtration material spirally wound around the tube such that the cartridge has a tapered configuration with a first end of the cartridge being greater in diameter than the second end. The present invention also relates to a filtration device having a filter cartridge housing adapted to receive the above mentioned tapered filter cartridge.

US Patent:

40207838, May 3, 1977

Filed:

Jun 19, 1975

Appl. No.:

5/588291

Inventors:

Erland D. Anderson - Eden Prairie MN
David S. Paulson - Elko MN
Bruce M. Sullivan - Burnsville MN

Assignee:

Donaldson Company, Inc. - Minneapolis MN

International Classification:

G01L 708

US Classification:

116114PV

Abstract:

A device for monitoring the condition of a filter element, comprising a combined clamping nut and differential pressure indicator. The body of the device is non-circular about an axis to facilitate its use as a wingnut, and has an outer surface and an inner surface through which passes an axial orifice, internally threaded to engage a threaded mounting rod. A differential pressure responsive device of novel design, including a slack diaphragm and an air-permeable translucent screen, is mounted in a further orifice in the outer surface for exposure of one side of the diaphragm to the pressure outside the filter, and a passage in the body connects the further aperture with the inner surface to supply to the other side of the pressure responsive device the pressure within the filter. The combination of such an arrangement with an air cleaner having a safety filter is also a part of the invention, as is the method of monitoring the filter conditions which the structure makes possible.