Granted Patent
Utility
US 4,652,217 · App. 06/722,771
Double acting type compressor
Inventor:
Tsunenori Shibuya
Patented Case
View Patent ↗
Granted: Mar 24, 1987
Filed: Apr 12, 1985
Inventor
Tsunenori Shibuya
Assignee (at issue)
Diesel Kiki Co., Ltd.
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.