Patents by Inventor Frederick M. Hewitt

Frederick M. Hewitt 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).

  • Apparatus for extruding reinforced concrete
    Patent number: 4067676
    Abstract: Apparatus for forming concrete articles in which augers convey "no-slump" concrete mix to a molding station with sufficient force to consolidate the mix. Friction is reduced at form surfaces of the molding station by high frequency vibration, greater than 22,000 vibrations per minute. Core-forming mandrels are disposed axially lateral of the line of flight of the augers. The concrete can be prestressed utilizing pre-tensioning or post-tensioning mechanism and provision is made for transverse reinforcement of the concrete.
    Type: Grant
    Filed: June 21, 1976
    Date of Patent: January 10, 1978
    Inventor: Frederick M. Hewitt
  • Apparatus for extruding concrete
    Patent number: 3994639
    Abstract: Apparatus for forming concrete articles in which augers convey "no-slump" concrete mix to a molding station with sufficient force to consolidate the mix. Friction is reduced at form surfaces of the molding station by high frequency vibration, greater than 22,000 vibrations per minute. Core-forming mandrels are disposed axially lateral of the line of flight of the augers. The concrete can be prestressed utilizing pre-tensioning or post-tensioning mechanisms and provision is made for transverse reinforcement of the concrete.
    Type: Grant
    Filed: December 19, 1974
    Date of Patent: November 30, 1976
    Inventor: Frederick M. Hewitt