Patents by Inventor James M. Grupa

James M. Grupa 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).

  • Airflow regulator
    Patent number: 5348449
    Abstract: A passive aspirator based on the Venturi effect has a pivotable flap in the inlet portion of a first air passage. The flap reduces the air flow through the passage when high pressure is present. A spring biases the flap toward an open position. Increasing air flow overcomes the spring force and tends to close the flap. This variable-volume flow allows use of a large enough passage to aspirate sufficient air at low flow rates but does not produce excess waste air at high flow rates.
    Type: Grant
    Filed: November 19, 1992
    Date of Patent: September 20, 1994
    Assignee: Lake Center Industries, Inc.
    Inventors: Robert A. Wilke, James M. Grupa