Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4298079 | Rotary drill bit | Angelo Vignotto, Mario Micca | 1981-11-03 |
| 4255000 | Rotary drill bit | Armin Olschewski, Lothar Walter, Manfred Brandenstein, Heinrich Kunkel | 1981-03-10 |