| # | Country | Total Patents | |
|---|---|---|---|
| #1 | France | 15 | |
| #2 | United States | 1 |
| # | Industry | |
|---|---|---|
| #1 | Thermal processes | |
| #2 | Electrical machinery and energy | |
| #3 | Materials and metallurgy | |
| #4 | Chemical engineering |
| # | Technology | |
|---|---|---|
| #1 | Details of furnaces | |
| #2 | Special electric heating or lighting | |
| #3 | Metal tempering | |
| #4 | Furnaces | |
| #5 | Drying solid materials by removing liquid | |
| #6 | Alloys | |
| #7 | Chemical or physical processes |
| # | Name | Total Patents |
|---|---|---|
| #1 | Hermann Henke | 1 |
| Publication | Filing date | Title |
|---|---|---|
| US2140228A | Electrically heated furnace |