The invention provides a hill starting assistance
system, which gathers multifaceted electrical signals, automatically controls releasing and triggering of a hill starting assistance function, and does not affect the normal driving operation; and the function is achieved simply, calibration is easy, and the cost is low. A total braking valve is connected with a first
pressure switch, and then is connected into a first opening of a
relay control
piston of a differential
relay valve in a communication mode, a parking braking air cylinder is connected with an air inlet of a two-position three-waynormally closed
solenoid valve, an air outlet of the two-position three-way normally closed
solenoid valve is connected with a second
pressure switch, and then connected with a second opening of therelay control
piston of the differential
relay valve in a communication mode, an air vent of the two-position three-way normally closed
solenoid valve is in communication with the
atmosphere, a firstcommunication opening of a main
piston of the differential
relay valve is connected with a rear bridge loop air cylinder, a second communication opening of the main piston of the differential
relay valve is connected with a middle rear bridge
brake chamber, and TCUs are correspondingly electrically connected with the first
pressure switch, the second pressure switch, the two-position three-way normally closed solenoid valve, a hill detection unit, and a function release switch through connecting lines.