Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4694917 | Mechanical jarring devices for use in drilling | Johannes Witte | 1987-09-22 |
| 4523765 | High pressure sealing means for longitudinally movable parts of deep-well drilling tools | — | 1985-06-18 |
| 4511007 | Locking device for a tool with telescopically displaceable parts | Thomas Jung | 1985-04-16 |