Issued Patents All Time
Showing 1–17 of 17 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 9915097 | Bearing section of a downhole drilling motor | Curtis E. Leitko, Jr., Rory J. Mallard, Jr. | 2018-03-13 |
| 9546518 | Power section and transmission of a downhole drilling motor | Curtis E. Leitko, Jr., Rory J. Mallard, Jr. | 2017-01-17 |
| 6540034 | Portable seismic shothole drilling system | Noel Evan Browne | 2003-04-01 |
| 6457538 | Advanced coring apparatus and method | J. Christopher Hetmaniak, Curtis E. Leitko, Jr., William J. McDonald | 2002-10-01 |
| 6313755 | Downhole buried utility sensing and data transmission system and method | J. Christopher Hetmaniak, William J. McDonald | 2001-11-06 |
| 6012532 | Method and apparatus for prevention, suppression or mitigation of explosions in confined subterranean chambers | Karl F. Kiefer, John H. Cohen | 2000-01-11 |
| 5641909 | Scan assembly structure | Karl F. Kiefer, Donald Chaffee, C. Grissom Steele, Terry P. Clifton | 1997-06-24 |
| 5624206 | Apparatus and method for supporting pipe main repair tools in an excavation | John H. Cohen, Curtis E. Leitko, Jr., Terry P. Clifton, Gerald Rockower | 1997-04-29 |
| 5467083 | Wireless downhole electromagnetic data transmission system and method | William J. McDonald, Charles Grissom Steele, Karl F. Kiefer, Terry P. Clifton, Curtis E. Leitko, Jr. | 1995-11-14 |
| 5462077 | Apparatus and method for shutting off fluid flow in a pipe main | John H. Cohen, Curtis E. Leitko, Jr., Terry P. Clifton, Gerald Rockower | 1995-10-31 |
| 5277055 | Impact and impact-rotary tool testing apparatus using rotary speed and impact energy | William J. McDonald, Terry P. Clifton, William Christian Herben | 1994-01-11 |
| 4949795 | Rotary rapid excavation system | William C. McDonald, John H. Cohen | 1990-08-21 |
| 4880065 | Air motor operated rotary earth drilling tool | William J. McDonald, Michael R. Wasson, Curtis E. Leitko, Jr., William C. Maurer | 1989-11-14 |
| 4858704 | Guided earth boring tool | William J. McDonald, William C. Maurer, Michael R. Wasson, William Christian Herben | 1989-08-22 |
| 4694913 | Guided earth boring tool | William J. McDonald, William C. Maurer, Michael R. Wasson, William Christian Herben | 1987-09-22 |
| 4632191 | Steering system for percussion boring tools | William J. McDonald, William C. Maurer, John H. Cohen, Gregory C. Givler | 1986-12-30 |
| 4621698 | Percussion boring tool | William J. McDonald, William C. Maurer, John H. Cohen, Gregory C. Givler | 1986-11-11 |