Patents by Inventor Robert G. Bearcroft

Robert G. Bearcroft 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).

  • Active attenuation of recurring sounds
    Patent number: 4153815
    Abstract: This invention concerns a method of, and apparatus for, reducing the ambient noise level at a location in the vicinity of a source of recurring noise. In its preferred embodiments the invention involves generating a series of cancelling noise signals which are exactly synchronized with the bursts of recurring noise from the source and adapting the cancelling signals in the series on the basis of the success achieved in nulling the noise from the source at the location.
    Type: Grant
    Filed: May 3, 1977
    Date of Patent: May 8, 1979
    Assignee: Sound Attenuators Limited
    Inventors: George B. B. Chaplin, Roderick A. Smith, Robert G. Bearcroft