Granted Patent
Utility
US 4,904,880 · App. 07/227,794
Automatic door driving system
Inventor:
Yukio Yoshida
Patented Case
View Patent ↗
Granted: Feb 27, 1990
Filed: Aug 3, 1988
Inventor
Yukio Yoshida
Assignee (at issue)
Yoshida Kogyo K.K.
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.