Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4701932 | Method for regulating the electrodes in a furnace having freely burning electric arcs | Karlheinz Bretthauer | 1987-10-20 |
| 4683577 | Method and apparatus for regulating arc discharge furnace | Karlheinz Bretthauer | 1987-07-28 |
| 4663764 | Method and apparatus for electrically balancing three-phase arc discharge furnaces | Karlheinz Bretthauer | 1987-05-05 |