Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5107180 | System for operating a portable lamp | Rainald Greve | 1992-04-21 |
| 4870700 | Personal safety radio device | Hans J. Schwalb | 1989-09-26 |
| 4495495 | Staff-location and signalling system for use in mines | Helmut Neumann | 1985-01-22 |