Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4276629 | Solar battery timepiece | Osamu Matsumura, Yutaka Kato, Ryo Namiki | 1981-06-30 |
| 4234948 | Watchglass fixing structure | Yasuo Maekawa, Masahiko Waki, Hiroshi Koide, Kisuke Watanabe, Osamu Matsumura +1 more | 1980-11-18 |