Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4668018 | Rotary cutter with spray nozzles for removal of ores from mine faces | Walter Hemmer, Reinhard Schiel | 1987-05-26 |
| 4660892 | Sectorial sprinkling device for coal mining | — | 1987-04-28 |
| 4647112 | Rotary cutter for gouging out ore from mine faces | Walter Hemmer, Reinhard Schiel | 1987-03-03 |