Issued Patents All Time
Showing 1–6 of 6 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| D333917 | Earphone case | Kazue Kato | 1993-03-16 |
| D325578 | Transmitter for a headphone | Ryuta Kanno, Katsumi Yamatogi | 1992-04-21 |
| D319241 | Headphone | Akira Yamazaki, Katsumi Yamatogi | 1991-08-20 |
| D318864 | Earphone | Kazue Kato | 1991-08-06 |
| D311007 | Earphone | — | 1990-10-02 |
| D310081 | Headphone | Katsuo Takada | 1990-08-21 |