Patents Assigned to Hoffmann & Co. Elektrokohle KG
  • Collector shoe and method for producing it
    Patent number: 5285126
    Abstract: A press-molded collector shoe having a body made of a first carbon piece, and a layer disposed on a side thereof made of a second, less conductive carbon piece. The second piece covers only a portion of the side of the collector shoe. An electrical lead projects from a portion of the side which is not covered by the second piece. During the production of the collector shoe the surface layer is pre-pressed in a separate step and the first carbon piece into which the lead wire is imbedded and the second piece are then pressed together.
    Type: Grant
    Filed: June 18, 1991
    Date of Patent: February 8, 1994
    Assignee: Hoffmann & Co. Elektrokohle KG
    Inventors: Peter Hoffmann, Johann Hoell
  • Sliding contact arrangement for carbon brushes
    Patent number: 5114351
    Abstract: A spring carbon brush which can be slid into a holder is blocked in the corresponding feed position on the holder when acted on by forces opposed to the direction of feed by a catch or expansion device in such a way that it can only move in the direction opposed to the direction of feed by overcoming an additional, preferably gradual, elastic force.
    Type: Grant
    Filed: April 27, 1990
    Date of Patent: May 19, 1992
    Assignee: Hoffmann & Co. Elektrokohle KG
    Inventor: Peter Hoffmann