Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 8356677 | Methods of preloading a sonic drill head and methods of drilling using the same | Kristian S. Drivdahl, Robert E. Able, Kenneth Carl Altrichter | 2013-01-22 |
| 8006782 | Sonic drill head | Kristian S. Drivdahl, Robert E. Able, Kenneth Carl Altrichter | 2011-08-30 |
| 7905161 | Process of drill bit manufacture | Drew Mark Butler, Erik M. Gaugh | 2011-03-15 |