Issued Patents 2004
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6712163 | Rock drilling tool | Hans-Werner Bongers-Ambrosius, Udo Hauptmann, Martin Richter | 2004-03-30 |
| 6675917 | Twist drill bit for rock drilling | Hans-Werner Bongers-Ambrosius | 2004-01-13 |