Abstract: A motor vehicle bumper system includes a bumper unit having pairs of hydraulic cylinders controlled to move a bumper between an extended position and a retracted position, a pump controlled to pump the oil from an oil tank to the hydraulic cylinders to move the bumper between the extended position and the retracted position, a pressure-setup pipe unit connected between the hydraulic cylinders, the pump and the oil tank and equipped with a decompression valve and controlled by a direction control valve to let the oil be alternatively pumped to upper oil chambers and lower oil chambers of the hydraulic cylinders to retract or extend out the bumper, and a pressure-relief pipe unit using a relief valve and an accumulator to release pressure from the hydraulic cylinders and a hydraulic oil pressure sensor to control the explosion time of the air bag of the motor vehicle.

Abstract: A shock-absorbing bumper system for an automotive vehicle includes a conduit subsystem for conducting hydraulic fluid therein, a supply subsystem for supplying hydraulic fluid, a pressure-balancing subsystem for regulating the pressure of hydraulic fluid, front and rear bumper subsystems for respectively extending and retracting front and rear bumpers and for absorbing shock, a switching subsystem for directing hydraulic fluid, and a feedback subsystem for absorbing shock.