Patents by Inventor Halbert B. Dunn

Halbert B. Dunn 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: 4247120
    Abstract: A needle for the acoustic sound box of old phonographs and gramophones is provided with a tip comprising a bearing plate which runs on the top surface of the recording on either side of a groove and a point which conforms to the groove. Both the bearing plate and the point comprise or consist of a low-friction polymer, especially polytetrafluoroethylene. The tip may be coated with the polymer or may be made therefrom, including the case where it deforms during playing to conform to the groove. The needle is especially useful in the re-recording of old cylinders and records using a microphone to capture the sound emanating from the horn or the phonograph or gramophone.
    Type: Grant
    Filed: March 13, 1979
    Date of Patent: January 27, 1981
    Inventor: Halbert B. Dunn