Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4475749 | Flange coupling | Gerhard Pforr, Max Appl, Erfried Voelkl, Hans Stark | 1984-10-09 |
| 4324570 | Apparatus for de-dusting gases | Gerhard Pforr, Guenter Schippmann, Max Appl, Erfried Voelkl, Hans Stark | 1982-04-13 |