Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6394558 | Method and apparatus for applying a brake force in a towed vehicle hydraulic brake system proportional to a hydraulic pressure generator power input | — | 2002-05-28 |
| 6296323 | Method and apparatus for applying a brake force in a towed vehicle hydraulic brake system proportional to a hydraulic pressure generator power input | — | 2001-10-02 |
| 5779324 | Towed vehicle brake system | David E. Frye, Jeffrey Swanson | 1998-07-14 |
| 5775102 | Power-assisted hydraulic steering system | David E. Frye | 1998-07-07 |
| 5735124 | Internally boosted master cylinder | David E. Frye | 1998-04-07 |
| 5655429 | Hydraulic pilot brake valve | David E. Frye | 1997-08-12 |
| 5368372 | Hydraulic brake system for an off-road vehicle | David E. Frye | 1994-11-29 |
| 5346289 | Control valve for hydraulic braking system | David E. Frye | 1994-09-13 |