Patents by Inventor Donald A. Calleson

Donald A. Calleson 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).

  • Cigarette filter
    Patent number: 5568819
    Abstract: A cigarette includes a filter element including a carbon-containing paper or a paper containing molecular sieves. The paper contacts the filter material, such as cellulose acetate tow, within the filter element, either by circumscribing the filter material or by being gathered with non-carbon-containing filter material. The paper is useful as a plug wrap for a filter element. In several embodiments, longitudinal grooves are provided on the periphery of the filter element.
    Type: Grant
    Filed: June 22, 1994
    Date of Patent: October 29, 1996
    Assignee: R. J. Reynolds Tobacco Company
    Inventors: Jeffery S. Gentry, Karen M. Womble, Chandra K. Banerjee, Richard L. Blakley, Russell D. Barnes, Donald A. Calleson, Henry T. Ridings
  • Device for measuring the circumference of a cylindrical rod
    Patent number: 4185393
    Abstract: The hand held measuring device measures the circumference of a cylindrical rod by moving the rod through a measured path between two cylinders. An ink marking device is used to place an index mark on the rolling rod and a transparent scale is used at the end of the measured surface of the outer cylinder to indicate the distance the rod has travelled. Coincidence of the index mark with the scale reading is a measure of the circumference of the rod. The device is operated manually via a hand wheel secured to a trunnion of the inner cylinder.
    Type: Grant
    Filed: September 25, 1978
    Date of Patent: January 29, 1980
    Assignee: Liggett Group Inc.
    Inventor: Donald A. Calleson
  • Apparatus for measuring smoke dilution in a vented-filter cigarette
    Patent number: 4171635
    Abstract: As a puff generator draws a volume of smoke and air through the vented-filter cigarette air is drawn from a ventilation cylinder to cause a piston to travel to a dead center position. The amount of movement of this piston is a measure of an amount of air drawn through the ventilation path of the filter by the puff generator. The amount of travel can be related to the total possible stroke of the piston so as to produce a digital read out of the degree of ventilation directly.
    Type: Grant
    Filed: October 30, 1978
    Date of Patent: October 23, 1979
    Assignee: Liggett Group Inc.
    Inventors: Donald A. Calleson, Ned A. Sigmon