Issued Patents 2004
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6823897 | Four-way switching valve | Hisatoshi Hirota, Katsumi Koyama | 2004-11-30 |
| 6783110 | Proportional solenoid valve | Hisatoshi Hirota, Tokumi Tsugawa, Katsumi Koyama, Yuusuke Inoue | 2004-08-31 |