Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4839904 | Apparatus for the melting of metals | Aljet Harberts, Josef Heimerl | 1989-06-13 |
| 4803398 | Electron gun with one directly heatable and one indirectly heatable cathode | Reinhardt Kraft | 1989-02-07 |