Granted Patent
Utility
US 4,576,515 · App. 06/533,744
Pipe laying apparatus
Inventors:
Keiji Morimoto, Shuichi Satoh, Yoshiyuki Iwai, Osamu Ae, Masao Suda, Kiyoshi Tsuchiya, Kojiro Ogata, Naoki Miyanagi
Patented Case
View Patent ↗
Granted: Mar 18, 1986
Filed: Sep 19, 1983
Inventors
Keiji Morimoto
Shuichi Satoh
Yoshiyuki Iwai
Osamu Ae
Masao Suda
Kiyoshi Tsuchiya
Kojiro Ogata
Naoki Miyanagi
Assignees (at issue)
Nippon Telegraph and Telephone Public Corporation
HITACHI CONSTRUCTION MACHINERY 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.