Issued Patents All Time
Showing 1–8 of 8 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6633631 | Digital key telephone system and extension terminal device thereof | Toshiaki Tanaka, Hiroshi Mano, Yoshihito Nagano, Masayuki Tsurusaki, Takashi Watanabe +4 more | 2003-10-14 |
| 6496576 | Digital key telephone system and extension terminal device thereof | Toshiaki Tanaka, Hiroshi Mano, Yoshihito Nagano, Masayuki Tsurusaki, Takashi Watanabe +4 more | 2002-12-17 |
| 6456705 | Digital key telephone system and extension terminal device thereof | Toshiaki Tanaka, Hiroshi Mano, Yoshihito Nagano, Masayuki Tsurusaki, Takashi Watanabe +4 more | 2002-09-24 |
| 6408060 | Digital key telephone system and extension terminal device thereof | Toshiaki Tanaka, Hiroshi Mano, Yoshihito Nagano, Masayuki Tsurusaki, Takashi Watanabe +4 more | 2002-06-18 |
| 6377671 | Digital key telephone system and extension terminal device thereof | Toshiaki Tanaka, Hiroshi Mano, Yoshihito Nagano, Masayuki Tsurusaki, Takashi Watanabe +4 more | 2002-04-23 |
| 6373924 | Digital key telephone system and extension terminal device thereof | Toshiaki Tanaka, Hiroshi Mano, Yoshihito Nagano, Masayuki Tsurusaki, Takashi Watanabe +4 more | 2002-04-16 |
| 6263061 | Digital button telephone system and extension terminal for the same | Toshiaki Tanaka, Hiroshi Mano, Yoshihito Nagano, Masayuki Tsurusaki, Takashi Watanabe +4 more | 2001-07-17 |
| 5105461 | Telephone line interface circuit | Masayuki Tsurusaki | 1992-04-14 |