Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6244267 | Respirator with a pressure relief valve | — | 2001-06-12 |
| 5063925 | Controllable expiration valve arrangement for a ventilating apparatus | Helge Frank, Eric Hecker, Dieter Weismann, Peter Gebhardt | 1991-11-12 |