Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5370428 | Mechanism for releasably locking sashes in door-or window frames | Karl-Heinz Dreifert | 1994-12-06 |
| 5111615 | Window with pivotable sash and mechanism for locking the sash in closed position | Karl-Heinz Dreifert | 1992-05-12 |