Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4882054 | Vibratory screening machine with tiltable screen frame and adjustable discharge weir | William W. Derrick | 1989-11-21 |
| 4575421 | Non-clogging wear-reducing screen assembly for vibrating screening machine | James W. Derrick | 1986-03-11 |