Issued Patents All Time
Showing 1–6 of 6 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5422940 | Global subscriber group service system | Kazumi Endo, Mitsuyuki Mizuno, Nobuo Horiba, Kenji Awaji | 1995-06-06 |
| 4935957 | Key telephone system | Kinzi Tanaka, Kuniaki Shimoseki, Tetsuya Hiraji, Minoru Okumura | 1990-06-19 |
| 4831516 | Data transmission system between a main CPU board having a wait signal generating latch and a plurality of CPU boards | Kinzi Tanaka, Minoru Shigematsu, Minoru Okumura | 1989-05-16 |
| 4734936 | Ringing signal sending-out circuit | Jouji Tanaka, Masaaki Saito | 1988-03-29 |
| 4660219 | Extension ringing arrangement key telephone system | Kinzi Tanaka, Toru Tagawa, Minoru Okumura | 1987-04-21 |
| 4641337 | Key telephone system with means for operatively connecting another key telephone systems | Jouji Tanaka, Tetunobu Watanabe, Minoru Okumura | 1987-02-03 |