Patents by Inventor Hillard C. Van Zandt

Hillard C. Van Zandt 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: 4462764
    Abstract: A hydraulically powered long stroke pumping unit including support means with a first pump unit mounted on said support means. The first pumping unit includes a first pump cylinder and first piston means reciprocable in said first pump cylinder and a piston rod extending outwardly from said first pump cylinder. A second pump unit is mounted on the support means in opposed aligned, spaced relationship with said first pump unit, and the second pump unit includes a second pump cylinder and a second piston means reciprocable in the second pump cylinder. The second piston means includes a piston rod extending outwardly from the second pump cylinder toward the piston rod of the first pump cylinder. The piston rods extend toward one another along a common central longitudinal axis, and a pump drive bar is connected to the outermost ends of the piston rods. A hydraulic drive means is connected to selectively and positively drive the pump drive bar in opposite directions in a single plane.
    Type: Grant
    Filed: November 12, 1981
    Date of Patent: July 31, 1984
    Inventor: Hillard C. Van Zandt