Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5626215 | Speed limiting accessory drive | Alvin Berger, Roy E. Diehl | 1997-05-06 |
| 5611416 | Speed limiting accessory drive and crankshaft damper | Alvin Berger, Roy E. Diehl | 1997-03-18 |
| 4739679 | Bifilar pendulum vibration damper for automotive installation | Alvin Berger, Roy E. Diehl | 1988-04-26 |