Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4654931 | Hinge device with brake spring for tilting windows | Siegfried Sonneborn, Ernst Mack, Carl F. Gerstrom, Peter H. Sorensen | 1987-04-07 |
| 4621466 | Flashing frame for the installation of adjacent roof windows | Siegfried Sonneborn, Ernst Mack | 1986-11-11 |
| 4543753 | Flashing frame for the installation of adjacent roof windows | Siegfried Sonneborn, Ernst Mack | 1985-10-01 |