Patents by Inventor Gary Siewell

Gary Siewell 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).

  • Ink reservoir with essentially constant negative back pressure
    Patent number: 4509062
    Abstract: An ink reservoir which incorporates a negative back pressure source coupled to a membrane wall of the reservoir to prevent ink leakage from a reservoir orifice is disclosed. The back pressure is created by either a linear or nonlinear spring which can be either independent of, or integral with, the membrane. The result is freedom from ink leakage and improved quality printing when the reservoir is used in conjunction with an ink pen such as used in ink jet printing.
    Type: Grant
    Filed: November 23, 1982
    Date of Patent: April 2, 1985
    Assignee: Hewlett-Packard Company
    Inventors: Robert N. Low, Frank L. Cloutier, Gary Siewell