Issued Patents All Time
Showing 1–9 of 9 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5489163 | Drainage channel | — | 1996-02-06 |
| 5110235 | Locking component for securing a cover on a frame | Heinz Witschi | 1992-05-05 |
| 5106231 | Drainage channel having improved coping for receiving grate | — | 1992-04-21 |
| 5026202 | Sidewall extension member for a drainage channel | — | 1991-06-25 |
| RE33439 | Drainage channel with locking grate | Heinz Witschi, Heinz-Dieter Brink, Markus-Christian Amann | 1990-11-13 |
| 4630962 | Drainage channel with locking grate | Heinz Witschi, Heinz-Deiter Brink, Markus-Christian Amann | 1986-12-23 |
| 4621939 | Drainage channel | Heinz Witschi, Heinz-Dieter Brink, Markus-Christian Amann | 1986-11-11 |
| 4553874 | Slotted drainage grate with support | Markus-Christian Amann | 1985-11-19 |
| 4515498 | Slotted drainage grate with support | Markus-Christian Amann | 1985-05-07 |