Patents by Inventor Fred W. Johnson

Fred W. Johnson 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: 5154452
    Abstract: A tubular connection employing two separate non-concurrent threaded sections, each of which nearly decays, that is, runs out on a tubular surface, one on the outside diameter of the male tubular member, and one on the inside diameter of the female tubular member, thus providing a joint with nearly the strength of the tubular body in tension without the use of a coupling. The female tubular member is expanded through a cold swaging operation before being finished with the two threaded sections. Additionally, the connection features a torque stop and cylindrical seal in the middle of the two thread steps, where stresses may be kept low. The thread elements are reverse angle locking with S-shaped load flanks which reduce stress concentrations and provide a clamping action on the centralized seal. Because of this unique seal, the connection can take cyclic application of external and internal pressure without leaking, a feat non-coupled and non-upset connections of prior art have not achieved.
    Type: Grant
    Filed: September 18, 1991
    Date of Patent: October 13, 1992
    Assignee: Frederick William Johnson
    Inventor: Fred W. Johnson