Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4813295 | Fly-wheel unit with disengageable friction device | Hans-Jurgen Drexl, Franz Hartig, Manfred Caspar | 1989-03-21 |
| 4809830 | Torque transmitting torsional vibration damper device | Manfred Caspar, Harald Raab, Franz Hartig, Norbert Pieper, Wolfgang Grosspietsch | 1989-03-07 |