Patents by Inventor Marvin M. Christensen

Marvin M. Christensen 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: 4289807
    Abstract: Apparatus and method for the fusion processing of synthetic thermoplastic resinous materials, utilizing a first high-velocity stream of gas to transport the resinous material through an elongated passageway which directs the stream of gas and transported material onto a workpiece, thereby fusing the resinous material. The elongated passageway is defined by at least one wall having a plurality of foramina or pores through which a second stream of gas is directed to heat the resinous material to a fusion temperature and to provide a slip stream on the inner surface of the wall thereby preventing the resinous material from sticking to the surface. The first stream of gas may be heated to initiate or supplement the heating of the resinous material.
    Type: Grant
    Filed: March 3, 1980
    Date of Patent: September 15, 1981
    Assignee: The Dow Chemical Company
    Inventors: Marvin M. Christensen, Richard E. Zachary, Andra P. Dupont
  • Patent number: 4263121
    Abstract: A method is disclosed to fabricate shaped membranes or diaphragms with substantially leak-free seams suitable for use in electrolytic cells to produce a halogen and an alkali metal hydroxide. A preferred polymeric sheet material is formed into a desired configuration and a fusible substance is placed at or near the edges of the polymeric material prior to applying heat and, optionally, pressure to the fusible substance.
    Type: Grant
    Filed: October 10, 1979
    Date of Patent: April 21, 1981
    Assignee: The Dow Chemical Company
    Inventor: Marvin M. Christensen