Patents by Inventor Donald F. Durenberger

Donald F. Durenberger 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).

  • Patent number: 6073295
    Abstract: A sweeping machine has a chassis, wheels for supporting the chassis and a brush mounted on the chassis for rotation to throw debris over the brush and into a debris hopper mounted on the chassis behind the brush. There is a control lever on the chassis for raising and lowering the brush relative to a surface to be swept. As the brush wears, a recirculation flap is positioned between the brush and the debris hopper and located closely adjacent a rear portion of the brush to direct debris not reaching the debris hopper forwardly toward the brush sweeping zone. The recirculation flap is moved toward and away from the brush concurrently with movement of the brush toward the surface being swept as the brush wears, whereby the space between the rear portion of the brush and the recirculation flap remains relatively constant.
    Type: Grant
    Filed: August 25, 1998
    Date of Patent: June 13, 2000
    Assignee: Tennant Company
    Inventors: Donald F. Durenberger, Michael T. Basham, Joseph F. D'Costa
  • Patent number: 5991953
    Abstract: A sweeping machine includes a chassis with wheels supporting the chassis on a surface to be swept. There is a brush mounted on the chassis for rotation in a direction to throw debris over the brush and into a debris hopper mounted on the chassis behind the brush. A flap assembly is positioned in front of the brush and closely adjacent thereto. The flap assembly has a flexible lip which is in contact with a surface being swept during its normal position.
    Type: Grant
    Filed: August 25, 1998
    Date of Patent: November 30, 1999
    Assignee: Tennant Company
    Inventors: Donald F. Durenberger, Michael T. Basham, Joseph F. D'Costa