Patents by Inventor Don A. Proudfoot

Don A. Proudfoot 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).

  • Acoustic space absorber unit
    Patent number: 4319661
    Abstract: An acoustic space absorber unit is provided in which Helmholtz resonators are mounted within an enclosure composed of sound absorbing material, with the orifices of the resonators near to but spaced from the enclosing material. The Helmholtz resonators are tuned to low audible frequencies such as 125 Hz. The Helmholtz resonators enhance the sound absorption at low frequencies while the entire unit provides sound absorption throughout the entire audible range.
    Type: Grant
    Filed: February 4, 1980
    Date of Patent: March 16, 1982
    Assignee: The Proudfoot Company, Inc.
    Inventor: Don A. Proudfoot