Patents by Inventor Dieter Lettau

Dieter Lettau 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).

  • Process and apparatus for producing aromatized strand-shaped smoking material
    Patent number: 4995405
    Abstract: Aromatized liquid is introduced into the tobacco in the area of the settling path (AS) at a point at which nearly half the final tobacco layer has accumulated. Subsequently, the second half will settle thereon so that the inserted liquid is inside the final tobacco layer (15). Liquid is injected into the tobacco without the use of compressed air, thus excluding crystal formation. The injection rate of liquid is controlled responsive to the operating speed of the cigarette making machine.
    Type: Grant
    Filed: June 27, 1989
    Date of Patent: February 26, 1991
    Assignee: R. J. Reynolds Tobacco Company
    Inventor: K. Dieter Lettau
  • Thermal change-over switch
    Patent number: 4008453
    Abstract: A thermal change-over switch has a switch arm movable between first and second contact positions with an intervening dead center position, a temperature responsive bimetal element is connected to the switch arm through a prestressed resilient element so as to effect quick switch-over of the arm from either position to the other while maintaining contact pressure up to the time of switch-over.
    Type: Grant
    Filed: March 25, 1975
    Date of Patent: February 15, 1977
    Assignee: Grossag Gesellschaft Mit Beschrankter Haftung
    Inventors: Dieter Hacker, Rolf Jager, Dieter Lettau