Patents by Inventor Hagen Schaefer

Hagen Schaefer 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).

  • Shearbar/cutterhead monitoring system with spatially separated magnet
    Patent number: 6255812
    Abstract: A system for monitoring a distance between a relatively movable magnetically conductive shearbar and a magnetically conductive cutterhead in a forage harvester includes a permanent magnet and an induction coil which generates an electric signal corresponding to the distance and which is supplied to an evaluation circuit. The evaluation circuit separates the signal generated by the induction coil into a high frequency component and a low frequency component and forms a quotient therefrom.
    Type: Grant
    Filed: March 18, 1999
    Date of Patent: July 3, 2001
    Assignee: Deere & Company
    Inventors: Burkhard Voigt, Hagen Schaefer, Markus Braun