Patents by Inventor William W. Hopfer

William W. Hopfer 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: 5209482
    Abstract: This invention is a device to specifically develop certain muscle groups and techniques for golfers by utilizing a variable resistance means which may be attached to an object such as a door and utilizes a simulated golf club, D-handle or waist belt to permit free rotational movement of the users limb or torso through a series of exercises. The D-shaped handle having a stirrup and a roller located between the stirrup to allow axial movement of the roller and the stirrup relative to the variable resistance means. The waist belt having teeth on the rubber liner to prevent slipping of the belt upon the user turning their body. The variable resistance means being lengths of rubber tubing which vary the resistance as the user pulls against it.
    Type: Grant
    Filed: January 22, 1992
    Date of Patent: May 11, 1993
    Assignee: Swingflex Systems, Inc.
    Inventor: William W. Hopfer