Patents by Inventor Christopher J. Cawte

Christopher J. Cawte 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).

  • Sealing joints between cementitious articles
    Patent number: 5605028
    Abstract: Joints between vertical shafts such as concrete manhole elements are sealed by an elastomeric ring and a rigid locating ring. The locating ring keys into the elastomeric ring and holds it in place during and (optionally) after assembly. The principle is applied to various types of joint and the locating ring may be extended to form a liner for the shaft.
    Type: Grant
    Filed: November 3, 1994
    Date of Patent: February 25, 1997
    Assignee: Caswick Limited
    Inventor: Christopher J. Cawte