Patents by Inventor Keith F. Edwards

Keith F. Edwards 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: 4441505
    Abstract: A spirometer is provided having an air flow path with a housing extending between the ends of a container. A paddle wheel rotor rotates within a cavity and partially cuts across the flow path to define an air gap. The ratio of the cross sectional area of the air gap to the inlet to the flow path is approximately 1:3. A light source/detector is activated by a chopper wheel coaxially mounted with the rotor and adapted to rotate therewith. The detector generates a train of pulses proportional to the rotation of the rotor which in turn is proportional to the volume of air flowing through the air path.
    Type: Grant
    Filed: January 11, 1982
    Date of Patent: April 10, 1984
    Assignee: Kinetics Measurement Corp.
    Inventors: Raymond A. Edwards, Keith F. Edwards