Issued Patents 1989
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4862973 | Drilling derrick device | Eckhard Voigts, Hans H. Achilles, Adolf Haussler | 1989-09-05 |
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4862973 | Drilling derrick device | Eckhard Voigts, Hans H. Achilles, Adolf Haussler | 1989-09-05 |