Issued Patents All Time
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5161805 | Oil ring assembly | Haruhito Watanabe, Koichi Hasuike, Makoto Shiono | 1992-11-10 |
| 5129661 | Steel oil ring assembly | Sumio Ono, Hitoshi Hattori | 1992-07-14 |
| 5087055 | Steel oil ring assembly | Sumio Ono, Hitoshi Hattori | 1992-02-11 |
| 4979757 | Oil ring assembly | — | 1990-12-25 |