Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4418788 | Branch take-off and silencer for an air distribution system | Karl U. Ingard, Herbert Willke | 1983-12-06 |
| 4319521 | Air distribution system | Karl U. Ingard, Herbert Willke | 1982-03-16 |
| 4313522 | Static pressure regain coupler for an air distribution system | Karl U. Ingard | 1982-02-02 |
| 4295416 | Air distribution system | Karl U. Ingard, Herbert Willke | 1981-10-20 |
| 4223832 | Damper for an air distribution system | Thomas P. Rodgers, Herbert Willke | 1980-09-23 |
| 4182430 | Branch take-off and silencer for an air distribution system | Karl U. Ingard | 1980-01-08 |