Patents by Inventor H. David Dalquist

H. David Dalquist has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4962755
    Abstract: A method of performing an endarterectomy comprising the steps of exposing the blood vessel containing the atheroma to be excised, next forming an incision through the wall of the blood vessel at a location subtended by the atheroma, then inserting a probe through the incision and imparting ultrasonic vibrations to the probe while manipulating the probe relative to the atheroma to loosen the atheroma from the surrounding blood vessel and extracting the loosened atheroma through the incision. The further step of injecting a sterile liquid over the probe during its vibration has been found to enhance the ability of the probe to loosen the atheroma.
    Type: Grant
    Filed: July 21, 1989
    Date of Patent: October 16, 1990
    Assignee: Heart Tech of Minnesota, Inc.
    Inventors: Robert M. King, H. David Dalquist
  • Patent number: 4796776
    Abstract: A pressure cooker for use in microwave ovens includes a microwave permeable bowl shaped container, a microwave permeable dome cover, and a steel locking ring permanently attached to the cover for maintaining the container and cover in fluid-tight seal during use. A safety valve, formed of flexible tubing, encounters a projection of the container and is deformed into a closed configuration responsive to movement of the cover, relative to the container, toward a locking position. A pressure regulator valve, consisting of a metal core surrounded by an elastically deformable casing, is positioned over a pressure control opening in the cover to maintain a selected operating pressure level in the pressure cooker. A pressure indicator and relief assembly, contained in a pressure release opening through the cover, indicates positive pressure in the chamber and is ejected in the event of an abnormally high pressure inside the housing.
    Type: Grant
    Filed: February 19, 1987
    Date of Patent: January 10, 1989
    Assignee: Northland Aluminum Products, Inc.
    Inventors: H. David Dalquist, Jorgen A. Jorgensen, Lloyd G. Keleny, Donald W. Nygren, John N. Taylor