Patents by Inventor Bernhard Kiefel

Bernhard Kiefel 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: 4816192
    Abstract: The invention is directed to a handheld, portable tool such as a chain saw equipped with an internal combustion engine mounted in an engine housing. The engine has a carburetor defining an air-intake channel. A heating element is provided which is electrically connected to the generator of the chain saw and mounted on the carburetor in the region of the air-intake channel. The heating element has a positive temperature coefficient and a predetermined temperature region thereby preventing the carburetor housing and the throttle flap from heating to a temperature above a predetermined value. The heating element and the way it is mounted prevents icing at the carburetor in cold weather thereby enabling the engine to run uninterruptedly and uniformly especially when the engine idles.
    Type: Grant
    Filed: November 20, 1987
    Date of Patent: March 28, 1989
    Assignee: Andreas Stihl
    Inventors: Mohamed Abou-Aly, Eberhard Bohnacker, Bernhard Kiefel, Reinhard Gerhardy, Reinhard Friedrich, Erich Krauter
  • Patent number: 4691681
    Abstract: The invention is directed to an arrangement for controlling the intake air for the carburetor of a hand-held portable tool such as a motor-driven chain saw or the like. During winter operation, the cooling air that is heated by the engine cylinder is carried through a pass-through opening to the carburetor. During summer operation the pass-through opening is blocked by a slide that is pivotally mounted on a pivot axis. The slide selectively opens or closes the pass-through opening and is configured as a deflector which, in its open position baffles the heated cooling air from the engine cylinder and guides it toward the carburetor.
    Type: Grant
    Filed: June 26, 1986
    Date of Patent: September 8, 1987
    Assignee: Andreas Stihl
    Inventors: Klaus Hoppner, Bernhard Kiefel