Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5876470 | Abrasive articles comprising a blend of abrasive particles | — | 1999-03-02 |
| 5045091 | Method of making rotary brush with removable brush elements | Ernest J. Duwell | 1991-09-03 |
| 4705124 | Cutting element with wear resistant crown | Ernest J. Duwell | 1987-11-10 |