Issued Patents 1997
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5681988 | Apparatus for indicating the degree of dirtiness of a filter | Werner Schnabel | 1997-10-28 |
| 5620505 | Filter | Helmut Luka, Nikolaus Moser, Bruno M. Sommer, Manfred Wagner | 1997-04-15 |