Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 12292118 | Piston ring | Yushi Abe, Naoki Umeda, Akira Hikone | 2025-05-06 |
| 11680537 | Cylinder liner and cylinder bore | Naoki Umeda, Seiji Tamaki, Takashi Sato, Takashi Oizumi | 2023-06-20 |