Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4846607 | Device for the guiding and positioning of support plates on a demolition machine for underground construction | Erhard Spross, Hans-Rudolf Ruttimann | 1989-07-11 |
| 4832536 | Anchor drilling unit | Erhard Spross, Hans-Rudolf Ruttimann | 1989-05-23 |