Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4845413 | Device for controlling the field current of DC motors | Franz Hackl, Wolfgang Spitaler | 1989-07-04 |
| 4810955 | Measuring apparatus for determining the countervoltage of electric motors | Franz Hackl | 1989-03-07 |