Issued Patents 1989
Showing 1–7 of 7 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4884494 | Pressure cylinder | Roy Campbell | 1989-12-05 |
| 4883149 | Vehicle disc brakes of the liquid cooled type | Roy Campbell, Andrew P. Green | 1989-11-28 |
| 4865168 | Vehicle disc brakes of the liquid cooled type | Roy Campbell, Andrew P. Green | 1989-09-12 |
| 4862998 | Self-energizing disc brakes | Roy Campbell, Andrew P. Green, David Parry | 1989-09-05 |
| 4852351 | Dual-circuit master cylinder with solenoid opened reservoir valve | — | 1989-08-01 |
| 4809588 | Hydraulic piston and cylinder assemblies | Roy Campbell | 1989-03-07 |
| 4796730 | Self-energizing disc brakes | Roy Campbell, Eric Henson | 1989-01-10 |