Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 7079175 | Television intercom system | Hiroshi Sumiya, Toshitaka Iwata | 2006-07-18 |
| 6879670 | Collective housing intercom apparatus | Hiroshi Sumiya | 2005-04-12 |
| 6671360 | Intercom system for a building or apartment house | Hiroshi Sumiya, Kengo Nakata | 2003-12-30 |