Patents by Inventor John D. Parnum

John D. Parnum 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: 4373301
    Abstract: The invention provides apparatus and a method for use in machining cam profiles, and is suitable for use in grinding, milling, turning or otherwise forming cams. A workpiece, i.e. a cam blank, is rotated adjacent a machine tool (e.g. a grinding wheel) and is moved relative thereto laterally of its axis of rotation so that stock is removed from the workpiece to form a predetermined cam profile thereon. At the same time, the angular displacement of the workpiece relative to a datum is continuously monitored and the rotational speed of the workpiece is varied in dependence on its instantaneous angular displacement so that the stock can be removed at a substantially constant rate, preferably defined by a predetermined programme corresponding to the particular cam profile to be machined on the workpiece.
    Type: Grant
    Filed: September 28, 1979
    Date of Patent: February 15, 1983
    Assignee: The Newall Engineering Company Limited
    Inventors: John D. Parnum, Nigel T. Barber
  • Patent number: 4299061
    Abstract: The invention provides apparatus and a method for use in machining cam profiles, and is suitable for use in grinding, milling, turning or otherwise forming cams. A workpiece, i.e. a cam blank, is rotated adjacent a machine tool (e.g. a grinding wheel) and is moved relative thereto laterally of its axis of rotation so that stock is removed from the workpiece to form a predetermined cam profile thereon. At the same time, the angular displacement of the workpiece relative to a datum is continuously monitored and the rotational speed of the workpiece is varied in dependence on its instantaneous angular displacement so that the stock can be removed at a substantially constant rate, preferably defined by a predetermined program corresponding to the particular cam profile to be machined on the workpiece.
    Type: Grant
    Filed: May 9, 1980
    Date of Patent: November 10, 1981
    Assignee: The Newall Co., Ltd.
    Inventors: John D. Parnum, Nigel T. Barber