Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4995350 | 2-cycle uni-flow spark-ignition engine | Seiichiro Kumagai, Masakazu Okai, Hisashi Inaga | 1991-02-26 |
| 4977875 | Two-stroke-cycle uniflow spark-ignition engine | Seiichiro Kumagai, Masakazu Okai, Hisashi Inaga | 1990-12-18 |
| 4960089 | Combustion system | Yoshiyuki Wada, Tetuya Kamihara, Masahito Tatematsu, Koichi Suda | 1990-10-02 |
| 4922865 | Two-stroke-cycle uniflow spark-ignition engine | Seiichiro Kumagai, Masakazu Okai, Hisashi Inaga | 1990-05-08 |