Issued Patents All Time
Showing 1–5 of 5 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 12173799 | Oil control ring | Akira Hikone, Takashi Oguro, Toshihiro Yamaoka, Naoki Umeda | 2024-12-24 |
| 10072755 | Combination oil ring | Atsushi Nakazawa, Masahide Hama, Toshiyuki Shibuya | 2018-09-11 |
| 9845873 | Combination oil ring | Atsushi Nakazawa, Masahide Hama, Toshiyuki Shibuya | 2017-12-19 |
| 9726286 | Combination oil ring | Atsushi Nakazawa, Masahide Hama, Toshiyuki Shibuya | 2017-08-08 |
| 9458933 | Combination oil ring | Masahide Hama, Yutaka Kitazume | 2016-10-04 |