Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4506501 | Apparatus for repairing chains | Donald L. DeVall, Clarence L. Tennant | 1985-03-26 |
| 4478248 | Rotary valve | Donald L. DeVall | 1984-10-23 |
| 4416337 | Drill head assembly | Albert A. Phillips, Donald L. DeVall | 1983-11-22 |