Issued Patents All Time
Showing 1–5 of 5 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4380410 | Mine-roof support | Hans Bull, Gerhard Ewich, Gunther Kuschke, Josef Welzel | 1983-04-19 |
| 4330226 | Roof-support distancing apparatus | Josef Welzel, Hans Bull | 1982-05-18 |
| 4313698 | Hydraulic shield-type support | Gerhard Schorradt, Gunter Werth | 1982-02-02 |
| 4266892 | Hydraulic roof-support frame | — | 1981-05-12 |
| 4189258 | Walking mine-roof support | Hans-Jurgen Kahl | 1980-02-19 |