Patents by Inventor Thomas G. Nelson

Thomas G. Nelson 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: 5511898
    Abstract: A manhole includes a carriage mounted on the underside of the cover that cooperates with a supporting guide channel located across the mouth of the manhole. the guide channel can be rotated to an incline so that the carriage can easily roll onto and from the supporting guide member. The free end of the guide channel is raised and lowered by a standard ratchet wrench inserted through the cover so that the operator need not lift any part of the cover manually. Once raised to the ready position, the operator simply pulls laterally on the cover handle to roll the cover slightly upward and laterally from the manhole opening. Once the cover clears the manhole, the guide channel can be rotated up and outward to provide access to the entire manhole area , if desired. To replace the cover, the guide channel is rotated to again extend across the manhole, the cover/carriage assembly is rolled laterally on to the guide channel until the cover edge contacts the ring edge.
    Type: Grant
    Filed: October 11, 1994
    Date of Patent: April 30, 1996
    Assignee: Universal Valve Co., Inc.
    Inventors: Martin C. Pettesch, Michael P. Breheny, Christopher M. Andrews, Thomas G. Nelson, Joseph V. Milo