Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4685586 | Boiler penthouse access door | Robert L. Lewis | 1987-08-11 |
| 4574973 | Door system for precipitators and the like | Robert L. Lewis | 1986-03-11 |
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4685586 | Boiler penthouse access door | Robert L. Lewis | 1987-08-11 |
| 4574973 | Door system for precipitators and the like | Robert L. Lewis | 1986-03-11 |