Issued Patents All Time
Showing 1–15 of 15 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 10513951 | Frustoconically supported valve stem seal assembly | — | 2019-12-24 |
| 9371749 | Hybrid valve stem seal retainer assembly | Alexander Williamson, Robert W. Lehmann | 2016-06-21 |
| 9052018 | Eccentricity tolerant valve stem seal assembly | Robert W. Lehmann, Alexander Williamson | 2015-06-09 |
| 7299779 | Upside-down square-up valve stem seal | Mark A. Stamback | 2007-11-27 |
| 7013692 | Valve guide grooving tool | — | 2006-03-21 |
| 6938877 | Valve stem seal assembly | Troy D. Mc Arthy | 2005-09-06 |
| 6848671 | Valve spring anti-rotation apparatus | Steven M. Fisher | 2005-02-01 |
| 6764079 | Valve seal assembly with straight-walled retainer | Alexander Williamson | 2004-07-20 |
| 6764063 | Valve seal assembly with bottom flange seal | Troy D. McArthy | 2004-07-20 |
| 6450143 | Heavy-duty valve stem seal assembly | Mark A. Stamback | 2002-09-17 |
| 6270082 | Coextruded valve stem seal | — | 2001-08-07 |
| 6244235 | Heavy-duty valve stem seal assembly | Mark A. Stamback | 2001-06-12 |
| 6209504 | Heavy-duty valve stem seal | Mark A. Stamback | 2001-04-03 |
| 5701861 | Cylinder with hybrid bore surface | John D. Binford | 1997-12-30 |
| 5273134 | Oil consumption measurement system for internal combustion engine | Edward E. Lafever, John G. Spoonamore | 1993-12-28 |