Issued Patents All Time
Showing 1–14 of 14 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6633631 | Digital key telephone system and extension terminal device thereof | Toshiaki Tanaka, Hiroshi Mano, Setsuo Kimura, Yoshihito Nagano, Takashi Watanabe +4 more | 2003-10-14 |
| 6496576 | Digital key telephone system and extension terminal device thereof | Toshiaki Tanaka, Hiroshi Mano, Setsuo Kimura, Yoshihito Nagano, Takashi Watanabe +4 more | 2002-12-17 |
| 6456705 | Digital key telephone system and extension terminal device thereof | Toshiaki Tanaka, Hiroshi Mano, Setsuo Kimura, Yoshihito Nagano, Takashi Watanabe +4 more | 2002-09-24 |
| 6408060 | Digital key telephone system and extension terminal device thereof | Toshiaki Tanaka, Hiroshi Mano, Setsuo Kimura, Yoshihito Nagano, Takashi Watanabe +4 more | 2002-06-18 |
| 6377671 | Digital key telephone system and extension terminal device thereof | Toshiaki Tanaka, Hiroshi Mano, Setsuo Kimura, Yoshihito Nagano, Takashi Watanabe +4 more | 2002-04-23 |
| 6373924 | Digital key telephone system and extension terminal device thereof | Toshiaki Tanaka, Hiroshi Mano, Setsuo Kimura, Yoshihito Nagano, Takashi Watanabe +4 more | 2002-04-16 |
| 6263061 | Digital button telephone system and extension terminal for the same | Toshiaki Tanaka, Hiroshi Mano, Setsuo Kimura, Yoshihito Nagano, Takashi Watanabe +4 more | 2001-07-17 |
| 5335270 | Bell signal generating circuit | Takashi Watanabe | 1994-08-02 |
| 5105461 | Telephone line interface circuit | Setsuo Kimura | 1992-04-14 |
| 5040172 | Communication method utilizing channel highway and digital communication apparatus for realizing the same | Hiroshi Mano | 1991-08-13 |
| 5033081 | Key telephone system | — | 1991-07-16 |
| 4887264 | Digital key telephone system | Hiroshi Mano, Yoshikazu Sano, Junichi Shiomi | 1989-12-12 |
| 4852158 | Telephone system allowing hold releasing request from central office line | Tamotsu Wakabayashi, Hiroshi Mano, Hideyasu Mori | 1989-07-25 |
| 4764954 | Automatic gain control in a loudspeaker telephone set | Yasuji Sato, Takeshi Horiuchi, Hisashi Yamada, Minoru Tanaka, Akira Maekawa | 1988-08-16 |