Issued Patents 2003
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6653767 | Spark plug and ignition apparatus | Hitoshi Morita, Shinichi Okabe, Takehiko Kato, Hiroshi Yorita, Tetsuya Miwa | 2003-11-25 |
| 6621198 | Spark plug having iridum alloy tip, iron-based alloy tip bonding portion and stress relieving layer therebetween | Seiki Nakagawa | 2003-09-16 |
| 6523515 | Spark plug for internal combustion engines and manufacturing method thereof | — | 2003-02-25 |