Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4853582 | Spark plug for use in internal combustion engine | Yasuyuki Sato, Masaki Sugata | 1989-08-01 |
| 4845400 | Spark plug for internal-combustion engine | Kozo Takamura, Yasuyuki Sato | 1989-07-04 |