Patents by Inventor Robert Landgren

Robert Landgren 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 testing concrete expansion
    Patent number: 5487307
    Abstract: A method and apparatus is disclosed for measuring on-site expansive volumetric changes in hardened, shrinkage-compensated concrete samples. The sample is disposed in a cylindrical container having a strain gauge for measuring hoop stress which is correlated with expansion of the sample.
    Type: Grant
    Filed: February 10, 1994
    Date of Patent: January 30, 1996
    Assignee: Kalman Floor Company, Inc.
    Inventors: Robert Landgren, William F. Perenchio