Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4885441 | Circuit Breaker | Shinji Yamagata | 1989-12-05 |
| 4866226 | Multi-phase circuit breaker employing arc extinguishing apparatus | Hiroshi Fujii, Shinji Yamagata, Yoshiaki Kobayashi | 1989-09-12 |