Patents by Inventor Robert Francis Call

Robert Francis Call 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).

  • Dispenser with unitary plunger and seal construction
    Patent number: 4121739
    Abstract: A dispenser for precisely metering viscous fluids from a cartridge. The dispenser includes a cartridge body and a plunger having a piston head at its extremity. The plunger is unitarily configured from a plastic material, including seal rings in the piston head. Each piston head including two such seal rings axially spaced from one another and configured to include sharp peripheral edges permitting resilient wedging contact within the bore of the cartridge.
    Type: Grant
    Filed: April 20, 1977
    Date of Patent: October 24, 1978
    Assignee: Illinois Tool Works Inc.
    Inventors: William David Devaney, Robert Francis Call