Patents by Inventor Robert D. Pringle

Robert D. Pringle 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: 6381980
    Abstract: A sprinkler system for a condenser unit of an air conditioning system comprises a flue with a temperature responsive valve assembly releasably mounted therein. The flue is mounted atop the protective grill for the system fan so as to channel a portion of the fan's cooling air flow for the condenser therethrough. A bellows senses temperature changes within the flue and upon a selectable rise in temperature expands so as to urge the valve stem of a two-way poppet valve to a valve opening position. The open valve, connected to a water source, delivers water to an elongated fluid outlet line which is fastened along the grill surrounding the condenser unit. The elongated line comprises a plurality of segments connected by intermediate spray heads. The spray heads circumscribe the condenser with a cooling spray so as to reduce the temperature of the same.
    Type: Grant
    Filed: June 8, 2001
    Date of Patent: May 7, 2002
    Inventor: Robert D. Pringle
  • Patent number: 5311747
    Abstract: A sprinkler system for a condenser unit of an air conditioning system comprises a flue with a temperature responsive valve assembly releasably mounted therein. The flue is mounted atop the protective grill for the system fan so as to channel a portion of the fan's cooling air flow for the condenser therethrough. A bellows senses temperature changes in this air flow and upon a selectable rise in temperature expands so as to urge the valve stem of a two-way poppet valve to a valve opening position. The open valve, connected to a water source, delivers water to an elongated fluid outlet line which is fastened along the grill surrounding the condenser unit. The elongated line comprises a plurality of segments connected by intermediate spray heads. The spray heads circumscribe the condenser with a cooling spray so as to reduce the temperature of the same.
    Type: Grant
    Filed: June 30, 1992
    Date of Patent: May 17, 1994
    Inventors: Robert D. Pringle, John Prikkel, III
  • Patent number: 4586046
    Abstract: A countermeasures system technique for destroying threat radar frame of reference. Automatic change of false target pattern is accomplished by any one of three different switching schemes or by any combination of them. The switching schemes comprehend (a) changing polarity of digital counts delivered to system range position program matrix inputs; (b) alternately enabling and disabling selected outputs of the range position program matrix, and (c) interchanging selected input gates of the system angle position program matrix.
    Type: Grant
    Filed: June 13, 1973
    Date of Patent: April 29, 1986
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Robert D. Pringle, William A. O'Berry
  • Patent number: 4281663
    Abstract: A device for indicating the reaction of pulse rate to exercise. In preferred forms, the device measures the pulse rate at rest (R.sub.1), the elevated pulse rate (R.sub.2) resulting from the performance of a specified amount of work, and the recovery pulse rate (R.sub.3) at a specific time after ceasing exertion. The device includes calculating means for directly calculating a fitness index from the three pulse rates according to a chosen one of various formulae. The device also provides a visual or audible pulse output as a timing signal for performing the specified exercise.
    Type: Grant
    Filed: May 21, 1979
    Date of Patent: August 4, 1981
    Inventor: Robert D. Pringle
  • Patent number: 4005375
    Abstract: A radio frequency coupling device has a non-magnetic, dielectric substrate having a planar surface on which a ferrimagnetic disc-shaped film is epitaxially grown. Sections of surface-oriented transmission line such as coplanar waveguide or slot-line extend over the substrate surface and terminate over the disc. The ferrimagnetic material couples to the RF magnetic fields associated with the transmission line sections and provides a coupling therebetween which is tunable by adjusting a direct magnetic field applied to the disc. Low direct coupling between the sections is obtained by arranging their respective RF magnetic fields to be orthogonal at the disc.
    Type: Grant
    Filed: December 9, 1974
    Date of Patent: January 25, 1976
    Assignee: Microwave and Electronic Systems Ltd.
    Inventors: Robert D. Pringle, Ian F. Morton