Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4861536 | Method for manufacturing a sealing ring | Heinz Gross, Stefan Sponagel | 1989-08-29 |
| 4850097 | Method for the manufacture of a sealing ring with a sealing lip having hydrodynamically acting return elements | Heinz Gross, Stefan Sponagel | 1989-07-25 |