Patents by Inventor Mark D. Bidema

Mark D. Bidema 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: 5002274
    Abstract: A portable baseball batting practice device is disclosed as including a rectangular upright frame, defined by two separate upper and lower vertical frame sections retained and interposed by coupler units; frame is vertically supported by support members connected to each side of the upper vertical frame section and extending back vertically joined at support unit, retaining support members in position; a pair of extension legs join a baseball batting tee to the lower vertical frame section permitting horizontal to vertical rotation thereof; the baseball batting tee comprising of a pair of interchangable, flexible ball receiving elements and an upper tee stem inserted into a lower tee stem permitting height adjustability and retained vertically by tee base; a vertical flexible net is suspended from the upper vertical frame section covering the opening between the upper and lower vertical frame sections presenting an impact area for a driven ball.
    Type: Grant
    Filed: May 16, 1990
    Date of Patent: March 26, 1991
    Inventor: Mark D. Bidema