Patents by Inventor Marlan H. Haakenson

Marlan H. Haakenson 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).

  • Ambient air cooling system
    Patent number: 4244193
    Abstract: Apparatus for utilizing ambient air to provide supplemental cooling of a refrigerated enclosure in combination with a mechanical refrigeration system. Initial pull down of the temperature in a refrigerated enclosure to an intermediate temperature level is accomplished by a mechanical refrigeration system, or by an ambient air system in combination therewith. Cooling of the enclosure to a predetermined, low temperature level is achieved by actuating fans in response to the sensing of an outdoor temperature at or below a predetermined temperature level to draw relatively cool ambient air into the enclosure.
    Type: Grant
    Filed: August 24, 1979
    Date of Patent: January 13, 1981
    Inventor: Marlan H. Haakenson