Issued Patents 1997
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| D386148 | Portable power supply unit with AC-DC converter | Masao Katooka, Toru Arai, Shigeru Okamoto, Masaharu Tanaka | 1997-11-11 |
| D377335 | Portable power supply unit with AC-DC converter | Masao Katooka, Toru Arai, Shigeru Okamoto, Masaharu Tanaka | 1997-01-14 |