Issued Patents All Time
Showing 1–10 of 10 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 8561730 | Foot valve assembly for a down hole drill | Jing James Yao, Paul Campbell, William H. Dell, II, Timothy J. Plunkett | 2013-10-22 |
| 8550189 | Drive pin support | — | 2013-10-08 |
| 8215419 | Variable frequency control for down hole drill and method | Timothy J. Plunkett, Paul Campbell | 2012-07-10 |
| 8100200 | Chuck assembly for a down-hole drill | — | 2012-01-24 |
| 7832504 | Exhaust valve and bit assembly for down-hole percussive drills | Timothy J. Plunkett, Leland H. Lyon | 2010-11-16 |
| 5794516 | Piston for a self-lubricating, fluid-actuated, percussive down-the-hole drill | Leland H. Lyon | 1998-08-18 |
| 5711205 | Self-lubricating, fluid-actuated, percussive down-the-hole drill | Leland H. Lyon | 1998-01-27 |
| 5566771 | Reversible casing for a self-lubricating, fluid-actuated, percussive down-the-hole drill | Leland H. Lyon | 1996-10-22 |
| 5562170 | Self-lubricating, fluid-actuated, percussive down-the-hole drill | Leland H. Lyon | 1996-10-08 |
| 4557339 | Borehole conditioning apparatus | Charles L. Falknor, Vincent H. Vetter, Dalton K. Lyon | 1985-12-10 |