Granted Patent
Utility
US 5,180,785 · App. 07/601,391
Diaphragm and method for producing same
Inventors:
Masaru Uryu, Kunihiko Tokura, Kyouji Muraoka
Patented Case
View Patent ↗
Granted: Jan 19, 1993
Filed: Oct 23, 1990
Inventors
Masaru Uryu
Kunihiko Tokura
Kyouji Muraoka
Assignee (at issue)
SONY GROUP 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.