Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5017045 | Method and apparatus for controlling attitude of shield excavator | Yutaka Onishi, Shigeyoshi Tagata, Koichi Umeno | 1991-05-21 |
| 4813813 | Method for constructing a tunnel | Minoru Yamamoto | 1989-03-21 |