Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4304308 | Burner apparatus for making holes in coal seams | German Munding, Helmut Hopmann, Armin Sowa, Christian Beckeryordersandforth | 1981-12-08 |
| 4301875 | Method for making holes and producing gas in coal seams | German Munding, Helmut Hopmann, Armin Sowa, Christian Beckervordersandforth | 1981-11-24 |