| 摘要 |
In a vehicle such as a tractor or a trailer having fluid-operated spring brakes to which fluid is supplied under pressure for releasing the brakes from a locked condition, security means are provided to prevent unauthorized release of the brakes. The security means comprises a bistable solenoid valve for controlling the supply of fluid to the brakes, energizing circuit means for operating the valve, and limited access switching means operable to set the solenoid valve selectively in an open or a closed condition.
|
