Granted Patent
Utility
US 6,056,481 · App. 08/923,568
Method and device for monitoring the load on hydraulic powered shield supports for underground mining
Inventors:
Willy Watermann, Walter von der Linden, Wilfried Weigel
Patented Case
View Patent ↗
Granted: May 2, 2000
Filed: Sep 4, 1997
Inventors
Willy Watermann
Walter von der Linden
Wilfried Weigel
Assignee (at issue)
DBT Automation GmbH
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.