Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 10389091 | Spark plug for internal combustion engine and ignition system having spark plug | — | 2019-08-20 |
| 10148068 | Spark plug and semi-finished product thereof | Tomoaki Yonekura | 2018-12-04 |
| 8994257 | Spark plug for internal combustion engine and method for manufacturing same | Masaya Nakamura | 2015-03-31 |
| 8398447 | Method for manufacturing spark plug for internal-combustion engine | Ken Hanashi, Satoru Kadowaki, Tsunenobu Hori, Kenka Tsubota, Hirotaka Aida | 2013-03-19 |
| 8339021 | Spark plug for internal-combustion engine and method for manufacturing the same | Ken Hanashi, Satoru Kadowaki, Tsunenobu Hori, Kenka Tsubota, Hirotaka Aida | 2012-12-25 |
| 6676468 | Method of producing a spark plug | Kozo Takamura, Toshikazu Shimizu | 2004-01-13 |
| 6642638 | Spark plug with Ir-alloy chip | — | 2003-11-04 |