Granted Patent
Utility
US 6,155,356 · App. 09/426,635
Percussion tool
Inventors:
Atsuyuki Kikuchi, Sinki Ohtsu, Mutsuo Harada, Akihisa Yahagi
Patented Case
View Patent ↗
Granted: Dec 5, 2000
Filed: Oct 25, 1999
Inventors
Atsuyuki Kikuchi
Sinki Ohtsu
Mutsuo Harada
Akihisa Yahagi
Assignee (at issue)
Hitachi Koki 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.