Patents by Inventor Robert Ferrence

Robert Ferrence 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: 7409993
    Abstract: A weight spacer apparatus has a carrier which is tubular in shape and a spacer tube which is also tubular in shape for insertion into the carrier. The weight spacer apparatus also has a plurality of weight bars which may be inserted into the spacer tube after the spacer tube is inserted into the carrier and which are also removable from the spacer tube. In one embodiment, a weight tray is inserted into the spacer tube for receiving the weight bars, and the weight tray may be fabricated from half-round tubing with a welded plate to cover the diametric opening. In another embodiment, a center plate is attached inside the spacer tube along the length of the spacer tube to divide the spacer tube into first and second compartments.
    Type: Grant
    Filed: November 20, 2006
    Date of Patent: August 12, 2008
    Assignee: Schlumberger Technology Corporation
    Inventors: Chenghua Han, Bennie Gill, Mark C. Duhon, Robert Ferrence, Jerry D. Campbell, Jr., Ronald Lutz