Granted Patent
Utility
US 6,755,593 · App. 10/054,666
Pipe replacement method and rotary impact mechanism for pipe bursting
Inventors:
Steven W. Wentworth, Robert F. Crane, Paul Hau
Patented Case
View Patent ↗
Granted: Jun 29, 2004
Filed: Jan 22, 2002
Inventors
Steven W. Wentworth
Robert F. Crane
Paul Hau
Assignee (at issue)
Earth Tool Company LLC
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.