Granted Patent
Utility
US 6,223,971 · App. 09/533,561
Driving unit of a welding equipment
Inventor:
Yoshio Sato
Patented Case
View Patent ↗
Granted: May 1, 2001
Filed: Mar 22, 2000
Inventor
Yoshio Sato
Assignee (at issue)
OBARA CORPORATION
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.