Patents by Inventor Andreas Lutters

Andreas Lutters 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: 5165812
    Abstract: A refill lead writing instrument for stepped advancement of a lead has a spring biased clamping device for holding a lead in direction of its longitudinal axis against a writing pressure. The clamping device includes a clamping chuck supported in a clamping sleeve under a spring action and a longitudinally displaceable lead pipe against which the clamping chuck can abut. A gripping part is form-lockingly connected with a shaft so that the shaft and the gripping part are rotatable relative to one another about a common longitudinal axis. The shaft and the gripping part have opening of same diameters and provided with grooves. A longitudinally displaceable supporting pipe has strips guiding in the grooves, one of the grooves having an extension extending in direction of the writing pipe and formed as a recess in which one of the strips is turnable.
    Type: Grant
    Filed: August 26, 1991
    Date of Patent: November 24, 1992
    Assignee: A. W. Faber-Castell GmbH & Co.
    Inventor: Andreas Lutters