Granted Patent
Utility
US 4,994,655 · App. 07/363,883
Electro-fusion joint
Inventors:
Takayuki Handa, Naotake Uda
Patented Case
View Patent ↗
Granted: Feb 19, 1991
Filed: Jun 8, 1989
Inventors
Takayuki Handa
Naotake Uda
Assignee (at issue)
Mitsui Petrochemical Industries, 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.