| 摘要 |
The invention relates to a vehicle security system comprising a linear hydraulic actuator (3) of the piston and cylinder type connected between the vehicle chassis (4) and hand brake lever (1). The cylinder (3b) of the actuator is connected to a hydraulic circuit including a shuttle valve (9) and a non-return valve (10). When the system is unlocked, the shuttle valve is open, and hydraulic fluid is free to flow from a reservoir (8) via the shuttle valve, both into and out of the actuator cylinder (3b), allowing the piston (3a) and therefore the hand brake lever (1) to move freely in both directions for normal driver-operation of the hand brake. When the system is locked, the shuttle valve is closed, and the non-return valve (10) permits fluid flow, and therefore piston movement, in one direction only. In this condition, the hand brake lever (1) can be moved in a brake-application direction but not in a brake release direction. |
