Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4953778 | Method of making torsional vibration damper having a roll spun housing | Donald S. Johnson, Walter P. Pukalo, Ralph Yorio | 1990-09-04 |
| 4872369 | Torsional vibration damper having a roll spun housing and other improvements | Donald S. Johnson, Walter P. Pukalo, Ralph Yorio | 1989-10-10 |