Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5593585 | Spray system for cleaning a filter screen | — | 1997-01-14 |
| 4969942 | Glass melter exhaust duct cleaning method and apparatus | Ronald L. Schwenninger | 1990-11-13 |
| 4836775 | Air cooled rotary kiln collar | Robert B. Heithoff | 1989-06-06 |
| 4707175 | Method of preheating pulverulent batch material | Robert B. Heithoff | 1987-11-17 |
| 4529428 | Method and apparatus for feeding an ablation liquefaction process | — | 1985-07-16 |
| 4496387 | Transition between batch preheating and liquefying stages apparatus | Robert B. Heithoff, Ronald L. Schwenninger | 1985-01-29 |