Patents by Inventor Robert C. Elfers

Robert C. Elfers 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).

  • Reduced icing air valve
    Patent number: 5584666
    Abstract: Provision is made for an air control valve to bypass the ice forming exhaust of a reciprocating pressure activation chamber in a reciprocating double diaphragm pump utilizing the supply pressure to close a check valve in line between the valve and the chamber which is then opened to exhaust by exhaust fluid flow from the chamber.
    Type: Grant
    Filed: October 17, 1994
    Date of Patent: December 17, 1996
    Assignee: Ingersoll-Rand Company
    Inventors: Nicholas Kozumplik, Jr., Robert C. Elfers
  • Diaphragm pump
    Patent number: D370488
    Type: Grant
    Filed: August 28, 1995
    Date of Patent: June 4, 1996
    Assignee: The Aro Corporation
    Inventors: Nicholas Kozumplik, Jr., Robert C. Elfers, Douglas D. Purdy