Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5834733 | ARC welding machine | Hidetoshi Oyama, Toshinori Hongu, Koji Hamamoto | 1998-11-10 |
| 5270516 | Arc welding machine | Koji Hamamoto, Naoki Kawai, Tetsu Innami, Yoshinori Nishida | 1993-12-14 |