Number | Name | Date | Kind |
---|---|---|---|
554968 | Wyant | Feb 1896 | |
1774522 | Phipps | Sep 1930 | |
2884227 | Hjalsten | Apr 1959 | |
3112803 | Rowley | Dec 1963 | |
3382940 | Stebley | May 1968 | |
3688852 | Gaylord et al. | Sep 1972 | |
3952819 | Adcock | Apr 1976 | |
4190125 | Emmerich et al. | Feb 1980 | |
4406336 | Olsen et al. | Sep 1983 |
Entry |
---|
Development of a System for High Speed Drilling of Small Diameter Roof Bolt Holes--Final Report, Earth Mechanics Institute, Colorado School of Mines, U.S.D.O.E. Contract No. DE-AC01-76ET-12462, Apr. 1982. |