Patents by Inventor Karl F. Keilhau

Karl F. Keilhau 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: 4693475
    Abstract: A racket for ball games and more specifically, a tennis racket, has a frame forming a racket head, a shank and a grip secured to the shank with a force fit so that the grip may be turned in relation to the racket head into different settings. The force fit connecting elements are simple to manufacture, yet permit an exact stepless setting and a satisfactory transmission of the forces produced while still avoiding a slip clutch effect. The grip and the racket shank are joined with each other by a surface area of substantial size which assures the required frictional engagement for the force fit in the angular direction while providing a form locking connection in the axial direction. The shank is part of an integral, one-piece handle bar which also has a cylindrical section and a conical section integrally interconnecting the shank to the cylindrical section.
    Type: Grant
    Filed: September 10, 1985
    Date of Patent: September 15, 1987
    Inventor: Karl F. Keilhau