Granted Patent
Utility
US 4,367,375 · App. 06/186,579
Push-button dial circuit
Inventors:
Yuuji Tsuruga, Akihiro Kobayashi, Makoto Yoshitoshi, Yutaka Nishino
Patented Case
View Patent ↗
Granted: Jan 4, 1983
Filed: Sep 12, 1980
Inventors
Yuuji Tsuruga
Akihiro Kobayashi
Makoto Yoshitoshi
Yutaka Nishino
Assignees (at issue)
Iwasaki Tsushinki Kabushiki Kaisha
Nippon Telegraph and Telephone Public 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.