Patents by Inventor Dennis L. Hansen

Dennis L. Hansen 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: 5060396
    Abstract: A dryer used to remove a flammable solvent or vapors from a traveling web of material supported in flotation by opposing air bars. The dryer consists of a large metallic cylinder through which the web of material moves longitudinally. Seals in the ends of the metallic cylinder at the point of entry and point of exit of the traveling web provide for a control system to maintain the desired environment under controlled pressure within the metallic cylinder. The web of material travels successively through one or more zones within the metallic cylinder. In each drying zone, the web of material is exposed to pressurized atmosphere at predetermined temperatures. The solvent is recovered from the pressurized atmosphere by rapid cooling, membrane separation, or absorption. Sensors within each zone of the dryer measure the oxygen content of the pressurized atmosphere. If the oxygen content exceeds a given threshold, pressurized nitrogen or other inert gas is added.
    Type: Grant
    Filed: August 17, 1989
    Date of Patent: October 29, 1991
    Assignee: W. R. Grace & Co.-Conn.
    Inventor: Dennis L. Hansen
  • Patent number: 5001845
    Abstract: A control system for an industrial dryer used to remove a flammable solvent or vapors from a traveling web of material or the dryer. The dryer consists of a chamber which is preferably a large metallic cylinder through which the web of material moves longitudinally. Seals in the metallic cylinder at the points of entry and exit of the traveling web permit the control system to maintain the desired environment under controlled pressure within the metallic cylinder. The web of material travels successively through one or more zones within the metallic cylinder. At each zone, the web of material is exposed to a pressurized atmosphere which may be at increasingly higher temperatures. The solvent is recovered from the pressurized atmosphere by rapid cooling, membrane separation or absorption. Sensors within each zone measure the oxygen content of the pressurized atmosphere. If the oxygen content exceeds a given threshold, pressurized nitrogen or other inert gas is added.
    Type: Grant
    Filed: August 17, 1989
    Date of Patent: March 26, 1991
    Assignee: W. R. Grace & Co.,-Conn.
    Inventors: Gerald R. Norz, Steve J. Zagar, Dennis L. Hansen