Patents by Inventor Albert C. Ellenburg

Albert C. Ellenburg 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).

  • Patent number: 7392823
    Abstract: Improvement in a combination valve including check valve and pressure relief valve portions for regulating fluid flow pressure and direction in a hydraulic circuit, wherein a valve seat includes, in addition to a central aperture, a plurality of peripherally-spaced axial cross-port orifice holes, of same or differing diameter and a plurality of intersecting, circumferentially-spaced, radial, semicircular holes; a spring cap including four adjoining axial portions of differing outer diameters, with a first portion being a protrusion that locates an end of a relief valve compression spring, a second portion having flat outer tool locating surfaces used for rotating the spring cap for axial adjustment relative to a valve stem, a third portion having a reduced radial wall thickness for easy crimping thereof relative to a valve stem, and a fourth portion having a coaxial recess for centering and physically retaining one end portion of a check valve compression spring.
    Type: Grant
    Filed: December 1, 2005
    Date of Patent: July 1, 2008
    Assignee: Parker-Hannifin Corporation
    Inventors: Xingen Dong, Albert C. Ellenburg, Frank P. Holzschuh