Patents by Inventor Richard L. Zelinka

Richard L. Zelinka 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).

  • Self-spaced pleated filter
    Patent number: 5066400
    Abstract: A self-spaced pleated filter element is provided having panel elements including repeating cycles of corrugations separated by spans of uncorrugated filter material.
    Type: Grant
    Filed: October 9, 1990
    Date of Patent: November 19, 1991
    Assignee: Donaldson Company, Inc.
    Inventors: Gary J. Rocklitz, Douglas G. Crofoot, Richard L. Zelinka
  • Multi-layered microfiltration medium
    Patent number: 4650506
    Abstract: A multilayered microfiltration medium exhibiting high particle capture efficiency and minimal flow restriction having a base substrate layer, a fine fiber filtration or efficiency layer deposited on and adhered to the substrate layer and a nonhandleable, non-self-supporting protective cover layer which is self-adhering to the fine fiber layer and has a very smooth outer surface. Suitable cover layer materials include polystyrene and polycarbonate fibers.
    Type: Grant
    Filed: February 25, 1986
    Date of Patent: March 17, 1987
    Assignee: Donaldson Company, Inc.
    Inventors: Marty A. Barris, Richard L. Zelinka