Patents by Inventor Mark I. Frenkel

Mark I. Frenkel 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).

  • Straightway valve
    Patent number: 4489753
    Abstract: Disclosed is a straightway valve comprising a housing made from interconnected stiff members, closing members made as toothed plates (10) pinched between the adjacent stiff members. Every toothed plate (10) is made as teeth (11 or 12) having their roots secured to a backing (20).
    Type: Grant
    Filed: May 17, 1982
    Date of Patent: December 25, 1984
    Inventor: Mark I. Frenkel