Patents by Inventor Keith Buffard

Keith Buffard 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: 7781903
    Abstract: A wave energy converter with air compression (WECWAC) includes a cylinder and a piston located within the cylinder dividing the cylinder into an upper chamber and a lower chamber. The cylinder is fixedly attached to a spar whose up/down (heave) motion is restrained. The piston is fixedly attached to, and driven by, a float which moves generally in phase with the waves. Under typical wave conditions the piston functions to compress air within the upper chamber on its up stroke and within the lower chamber on its down stroke, i. e., the system is thus double-acting. In still water, the spar and cylinder combination is designed to drift down into the body of water relative to the piston whereby the size/volume of the upper chamber is decreased (while that of the lower chamber is increased). For small amplitude waves the piston continues to compress air in the upper chamber and this asymmetrical compression continues until the waves reach a predetermine level when “double-action” is resumed.
    Type: Grant
    Filed: May 16, 2007
    Date of Patent: August 24, 2010
    Assignee: Ocean Power Technologies, Inc.
    Inventors: Keith Buffard, Mark Draper, Keith Robert Pullen, Robin Rhodes
  • Publication number: 20080012344
    Abstract: A wave energy converter with air compression (WECWAC) includes a cylinder and a piston located within the cylinder dividing the cylinder into an upper chamber and a lower chamber. The cylinder is fixedly attached to a spar whose up/down (heave) motion is restrained. The piston is fixedly attached to, and driven by, a float which moves generally in phase with the waves. Under typical wave conditions the piston functions to compress air within the upper chamber on its up stroke and within the lower chamber on its down stroke, i. e., the system is thus double-acting. In still water, the spar and cylinder combination is designed to drift down into the body of water relative to the piston whereby the size/volume of the upper chamber is decreased (while that of the lower chamber is increased). For small amplitude waves the piston continues to compress air in the upper chamber and this asymmetrical compression continues until the waves reach a predetermine level when “double-action” is resumed.
    Type: Application
    Filed: May 16, 2007
    Publication date: January 17, 2008
    Inventors: Keith Buffard, Mark Draper, Keith Pullen, Robin Rhodes