Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 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 |