Issued Patents All Time
Showing 1–8 of 8 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4557631 | Off-center rock bolt anchor and method | David M. Donan | 1985-12-10 |
| 4453845 | Base thrust anchor shell assembly | — | 1984-06-12 |
| 4380407 | Dual thrust anchor shell assembly | — | 1983-04-19 |
| 4300859 | Dual diameter bushing/seal for mine roof bolt | — | 1981-11-17 |
| 4293244 | Pick arm anchor assembly | — | 1981-10-06 |
| 4188158 | Mine roof bolt hole seal | David M. Donan | 1980-02-12 |
| 4187040 | Mine roof bolt spike chemical dispenser assembly | — | 1980-02-05 |
| 4183699 | Washer/gasket for mine roof bolt assembly | David M. Donan | 1980-01-15 |