Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4886370 | Method for detecting a state of substance existing in pipe | Toshio Koshihara, Rokurou Misawa, Yuzo Sagawa | 1989-12-12 |
| 4872762 | Method and apparatus for detecting defective portion on inner surface of pipe | Toshio Koshihara, Rokurou Misawa, Yuzo Sagawa, Yuji Matoba, Koji Ishihara | 1989-10-10 |