Patents by Inventor Charles B. Knudson

Charles B. Knudson 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).

  • Resilient seal rings with dual lips
    Patent number: 4089533
    Abstract: A seal ring for use on a piston or rod has a static sealing periphery that provides sealing contact across its entire surface and includes an interference lip for high sealing contact and a dynamic sealing periphery that has large and small diameter portions with a flexible flared lip hinged to the end of the large diameter portion and extending from it along most of the length of the small diameter portion but being radially spaced from it.
    Type: Grant
    Filed: August 8, 1977
    Date of Patent: May 16, 1978
    Assignee: Microdot Inc.
    Inventor: Charles B. Knudson