| 摘要 |
A vehicle anti-theft system is remotely operable and includes a pump fluidically connecting a reservoir of hydraulic fluid to a hydraulic cylinder of a vehicle braking system. The system further includes a pump control circuit that operates the pump to pump fluid into the braking system hydraulic cylinder to lock the vehicle brakes and to stop the pump as soon as the pressure in the braking system reaches a predetermined value. In one form of the system, operation of a remotely controlled switch deactivates the system and re-orients a valving system so operation of the pump drains the braking system by moving hydraulic fluid from the braking system back into the fluid reservoir. The pump control circuit stops the pump when pressure in the braking system drops to a predetermined level, and can include a timer to automatically stop the pump after a predetermined time of draining operation whereby the draining does not deprive the braking system of sufficient fluid to operate in a normal manner. One form of the invention includes a reversible pump. Other forms of the system include op-amps, voice recognition circuits and transistor switches. |
