Issued Patents 2002
Showing 1–5 of 5 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6457906 | Mine stopping | William R. Kennedy | 2002-10-01 |
| 6425820 | Mine door power drive system | William R. Kennedy | 2002-07-30 |
| 6419324 | Method of sealing off a mine passageway | William R. Kennedy | 2002-07-16 |
| 6394707 | Yieldable mine roof support | William R. Kennedy | 2002-05-28 |
| 6379084 | Mine stopping | William R. Kennedy | 2002-04-30 |