Granted Patent
Utility
US 6,658,717 · App. 09/816,345
Duplex pipe end working method
Inventors:
Hiromi Takasaki, Yoshikazu Takamatsu, Nobuo Ichimura, Susumu Sato
Patented Case
View Patent ↗
Granted: Dec 9, 2003
Filed: Mar 26, 2001
Inventors
Hiromi Takasaki
Yoshikazu Takamatsu
Nobuo Ichimura
Susumu Sato
Assignee (at issue)
CALSONIC KANSEI 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.