Patents by Inventor Willem T. De Graaff

Willem T. De Graaff 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: 6326576
    Abstract: An electrical discharge machining (EDM) apparatus includes at least one work station having an electrode fixedly mounted to a base and a workpiece fixture slidingly mounted to the base above the electrode. A servomotor is mounted to the base and arranged to drive the workpiece fixture toward and away from the workpiece. Preferably, the EDM apparatus will include a number of such work stations, and each work station will be connected to a separate control system for independently controlling and energizing the work station.
    Type: Grant
    Filed: September 22, 1999
    Date of Patent: December 4, 2001
    Assignee: General Electric Company
    Inventors: Rudi O. Krenz, Willem T. De Graaff, Kenneth E. Mascarenas
  • Patent number: 6231035
    Abstract: A fixture for holding a workpiece in a predetermined position during a manufacturing operation. The fixture includes a support having a surface for receiving the workpiece. The surface has a reference point for locating and orienting the workpiece in the predetermined position. The fixture also includes a clamp for clamping the workpiece in a fixed position with respect to the reference point to hold the workpiece in the predetermined position and a brace mounted on the support for bracing the workpiece to prevent the workpiece from deforming during the manufacturing operation. The brace has at least two jaws adapted for clamping the workpiece when received by the support to prevent movement of the workpiece toward or away from the support.
    Type: Grant
    Filed: November 3, 1999
    Date of Patent: May 15, 2001
    Assignee: General Electric Company
    Inventors: Willem T. De Graaff, Allen L. Kelly
  • Patent number: 4868961
    Abstract: An apparatus for engraving vein cuts in a flat metal strip is described including a support adapted to support the metal strip thereon. Three air-driven motors are mounted on the support and have rotary cutting tools thereon which are utilized to cut angularly disposed vein cuts and a horizontally disposed vein cut in one surface of the metal strip. The strip is advanced across the support with the cutting tools being brought into engagement with the strip at the proper time to create the vein cuts therein. A punch is also mounted on the support for creating indexing notches at the lower edge of the strip. The sequential engraving and advancing of the strip through the support is controlled by a programmable controller.
    Type: Grant
    Filed: January 20, 1987
    Date of Patent: September 26, 1989
    Assignee: Coleman-Frizzell, Inc.
    Inventors: Samuel L. Coleman, Willem T. de Graaff