Issued Patents 1989
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4882470 | Boring device for opening passages to branch portions of a lined main pipe line | Katsuaki Zenbayashi, Hisao Otsuga, Akio Morinaga, Shinji Shimokawa | 1989-11-21 |
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4882470 | Boring device for opening passages to branch portions of a lined main pipe line | Katsuaki Zenbayashi, Hisao Otsuga, Akio Morinaga, Shinji Shimokawa | 1989-11-21 |