Issued Patents All Time
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 10757266 | Terminal device, and intercom system provided with terminal device | Seiya Yamakawa, Akira Kai | 2020-08-25 |
| 10659617 | Building controller and interphone system | Syu Kumagai | 2020-05-19 |
| 10616420 | Intercom system | Seiya Yamakawa, Hayato Takeya | 2020-04-07 |
| 10334114 | Collective housing/building entrance device and entryphone system having that collective housing/building entrance device | Seiya Yamakawa | 2019-06-25 |