Issued Patents All Time
Showing 1–5 of 5 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 7987943 | Apparatus and method for generating a seismic source signal | Zhouhong Wei, John Crowell | 2011-08-02 |
| 7628248 | Apparatus and method for generating a seismic source signal | Zhouhong Wei, John Crowell | 2009-12-08 |
| 5666328 | Three axis seismic vibrator | John Crowell, Rhys Michael Evans | 1997-09-09 |
| 5401919 | Removable piston bore liner for hydraulically actuated seismic vibrator | John Crowell | 1995-03-28 |
| 4718049 | Pre-loaded vibrator assembly with mechanical lock | John Crowell | 1988-01-05 |