Patents by Inventor Mary Kathleen Douglas, legal representative

Mary Kathleen Douglas, legal representative 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: 7422116
    Abstract: A self-propelled screening apparatus (1) having a chassis (11); a pair of endless tracks (12) supporting the chassis (11); a superstructure (13) rotatably mounted on the chassis (11); a prime mover (19) provided in or on the superstructure (13) and arranged to provide motive power to operate the endless tracks (12) and where the prime mover (19) is rotatable with the superstructure (13); and a screen box (16) mounted on the superstructure (13), also for rotation therewith. The screen box (16) has an input (17) for receiving a supply of bulk material, at least one screen deck for screening the bulk material, and an output for discharging screened material. The prime mover (19) and the screen box (16) are arranged on opposite sides of the rotational axis of the superstructure (13), to provide a stable weight distribution.
    Type: Grant
    Filed: August 31, 2001
    Date of Patent: September 9, 2008
    Assignee: Extec Screens and Crushers Limited
    Inventors: Mary Kathleen Douglas, legal representative, Patrick Joseph Douglas