Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 7712305 | Exhaust aftertreatment system with spiral mixer | David W. Kapsos, Mark P. Adams, Patrick Klein | 2010-05-11 |
| 6722123 | Exhaust aftertreatment device, including chemical mixing and acoustic effects | Z. Gerald Liu, Michael T. Zuroski, Kenneth J. Kicinski, C. Raymond Cheng | 2004-04-20 |
| 5693918 | Active exhaust silencer | C. Raymond Cheng | 1997-12-02 |
| 5602928 | Multi-channel communication system | Larry J. Eriksson | 1997-02-11 |
| 5172416 | Active attenuation system with specified output acoustic wave | Mark C. Allie, Larry J. Eriksson | 1992-12-15 |
| 5044464 | Active acoustic attenuation mixing chamber | — | 1991-09-03 |