Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4302133 | Device for supporting a gallery or a tunnel | Alfred Zitz | 1981-11-24 |
| 4263005 | Device for provisionally consolidating a gallery and suitable consolidating frame | Siegfried Sigott, Otto R. Schetine, Alfred Zitz | 1981-04-21 |