Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 10277976 | Speaker device having diaphragm with folded portion | Kenichi Oshima, Koji Takayama, Hiroyuki Dohi, Hayami Kondo | 2019-04-30 |
| 10264347 | Two-way speaker device having diaphragm of second speaker unit inside voice coil bobbin of first speaker unit | Kenichi Oshima, Koji Takayama, Hiroyuki Dohi, Hayami Kondo | 2019-04-16 |