Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4883717 | Vibration-damping material | Shuji Kitamura, Takuzo Okumura, Yoshio Tadokoro, Hiroo Toya, Yoshiaki Togawa +5 more | 1989-11-28 |
| 4871194 | Oil well pipe joint and manufacturing method therefor | Hisakazu Kawashima, Yoshiyasu Morita, Tetsuzo Arai, Kunihiro Fukui | 1989-10-03 |