Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4637225 | Air conditioning apparatus | Ralph C. Marshall | 1987-01-20 |
| 4182131 | High efficiency air conditioner | Ralph C. Marshall | 1980-01-08 |
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4637225 | Air conditioning apparatus | Ralph C. Marshall | 1987-01-20 |
| 4182131 | High efficiency air conditioner | Ralph C. Marshall | 1980-01-08 |