Patents by Inventor Robert M. Birch

Robert M. Birch 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).

  • Method and apparatus for tunnel lining
    Patent number: 4830536
    Abstract: A method and apparatus for tunnel lining is provided made up of arcuate liner segments having a formed body with two end walls and two substantially parallel sidewalls, at least two pins extending from one sidewall intermediate its length in the median plane of the body and transverse to said sidewall, a like number of openings in the other sidewall each adapted to receive one of said at least two pins from two adjacent interfitting segments and locking means in said opening permitting insertion of said at least two pins in said openings of adjacent segments and lockingly engaging the same against removal and urging said two adjacent fittings into tight end to end engagement.
    Type: Grant
    Filed: July 25, 1984
    Date of Patent: May 16, 1989
    Assignee: Commercial Shearing, Inc.
    Inventors: Robert M. Birch, Warren E. Brown