Issued Patents All Time
Showing 26–39 of 39 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 |
| 6470845 | Spark plug for internal combustion engine | — | 2002-10-29 |
| 6373172 | Spark plug for internal combustion engine having a straight pillar ground electrode | Tunenobu Hori | 2002-04-16 |
| 6346766 | Spark plug for internal combustion engine and method for manufacturing same | Tsunenobu Hori | 2002-02-12 |
| 6337533 | Spark plug for internal combustion engine and method for manufacturing same | Ken Hanashi, Tsunetoshi Goto | 2002-01-08 |
| 6307307 | Spark plug for internal combustion engine with Ir alloy molten portion outside spark discharge region | — | 2001-10-23 |
| 6262522 | Spark plug for internal combustion engine | Hironori Osamura, Nobuo Abe, Kenji Horibe | 2001-07-17 |
| 6094000 | Spark plug for internal combustion engine | Hironori Osamura, Nobuo Abe, Kenji Horibe | 2000-07-25 |
| 5990602 | Long life spark plug having minimum noble metal amount | Akio Katoh | 1999-11-23 |
| 5693999 | Multiple gap spark plug for internal combustion engine | Hironori Osamura | 1997-12-02 |
| 5581145 | Spark plug | Akio Kato | 1996-12-03 |
| 5557158 | Spark plug and method of producing the same | Kozo Takamura | 1996-09-17 |