Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6901905 | Pre-combustion chamber enrichment | Karl Stellwagen, Olaf Berger | 2005-06-07 |
| 6055953 | Gas engine having roller-shaped rotary slide valve | Karl Stellwagen, Heinz Willms | 2000-05-02 |