Issued Patents All Time
Showing 26–36 of 36 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 7055621 | Method and apparatus for replacement of underground pipe | Steven W. Wentworth | 2006-06-06 |
| 7028785 | Pneumatic impact piercing tool | — | 2006-04-18 |
| 6953095 | Method and system for operating a reversible pneumatic ground piercing tool | — | 2005-10-11 |
| 6923270 | Pneumatic impact piercing tool | — | 2005-08-02 |
| 6913091 | Method and apparatus for replacement of underground pipe | Steven W. Wentworth, Robert F. Crane | 2005-07-05 |
| 6860514 | Drill string joint | Steven W. Wentworth, Robert F. Crane | 2005-03-01 |
| 6761507 | Method and apparatus for replacement of underground pipe | Steven W. Wentworth | 2004-07-13 |
| 6533052 | Drill bit for impact-assisted directional boring | Steven W. Wentworth, Robert F. Crane, Randy R. Runquist, Richard K. Smith | 2003-03-18 |
| 6273201 | Pneumatic ground piercing tool with movable chisel head | Steven W. Wentworth, Robert F. Crane | 2001-08-14 |
| 5687803 | Method for reversing a ground piercing tool | Steven W. Wentworth, Robert F. Crane | 1997-11-18 |
| 5603383 | Reversible pneumatic ground piercing tool | Steven W. Wentworth, Robert F. Crane | 1997-02-18 |