Patents by Inventor Michael Bruce Mitchell

Michael Bruce Mitchell 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).

  • Preparing cigarette filters
    Patent number: RE29674
    Abstract: Cigarette filters are made by passing a continuous rod of filter material continuously through a moving die to form a continuous filter element having a repeated pattern of staggered grooves so arranged that the continuous filter element can be cut at regular intervals to form individual filter elements each having in its peripheral surface a number of grooves extending substantially axially alternately from opposite ends of the element.
    Type: Grant
    Filed: November 20, 1975
    Date of Patent: June 20, 1978
    Assignee: Molins Limited
    Inventors: Francis Auguste Maurice Labbe, Michael Bruce Mitchell