Patents by Inventor Frank S. Robinson

Frank S. Robinson 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).

  • Hollow reinforced concrete fence post and method and apparatus for making the same
    Patent number: 3933969
    Abstract: A wire reinforced hollow core concrete fence post is made by injecting concrete into a form in which is centrally supported a longitudinally extending mandrel having a plurality of radially extending spacers extending longitudinally along its surface, the spacers being adapted to support a cylindrical tube of wire mesh reinforcing remote from the surface of the mandrel. A pallet board is disposed in the bottom of the form for supporting the concrete injected therein. Means are provided to rotate the manadrel and the tube of wire mesh reinforcing while the concrete is being injected into the form. Means are also provided to withdraw the mandrel from the form after the concrete has been injected, while retaining the concrete and the reinforcing within the form.
    Type: Grant
    Filed: April 15, 1974
    Date of Patent: January 20, 1976
    Inventors: Frank R. Robinson, Frank S. Robinson