Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4654510 | PTC heating apparatus | Kazumasa Umeya, Ryoichi Shioi, Hisao Nakagawa, Shoji Koyama, Hideshi Kataoka | 1987-03-31 |
| 4245146 | Heating element made of PTC ceramic material | Ryoichi Shioi, Kazumasa Umeya, Kazunari Yonezuka | 1981-01-13 |