Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5073947 | Hearing device for a protective helmet | Tronje von dem Hagen, Balz Knabenhans | 1991-12-17 |
| 5027437 | Suit for the support of a person's body in respect to acceleration forces | Tronje von dem Hagen, Robin C. Huttenbach | 1991-07-02 |
| 4903346 | Multi-part protective helmet | Tronje von dem Hagen | 1990-02-27 |