Patent ID: 6752473
Filing Date: 2004-06-22
Classification: B60T

Abstract:
An electronically controlled brake system, comprising:an NO (normally open)-type solenoid valve arranged at an upstream line of a wheel brake and controlling a flow of pressurized oil fed from both a master cylinder and an outlet of an oil pump to said wheel brake; an NC (normally close)-type solenoid valve arranged at a downstream line of said wheel brake and controlling a flow of pressurized oil discharged from said wheel brake; an oil suction line connecting said master cylinder to an inlet of said oil pump and feeding pressurized oil from the master cylinder to the oil pump during a TCS (traction control system) mode; an NC-type shuttle valve mounted on said oil suction line to oven or close the oil suction line; a low/intermediate pressure accumulator connected to both an outlet of the NC-type solenoid valve and the oil suction line so as to store the pressurized oil discharged from the wheel brake during an ABS (anti-lock brake system) pressure reducing mode, and feed the stored pressurized oil to the inlet of the oil pump during an ABS pressure increasing mode, said pressure accumulator also storing the pressurized oil outputted from the oil pump to feed the stored pressurized oil to the inlet of the oil pump during an ESP (electronic stability program) mode; and an oil charging line extending from said outlet of the oil pump to the low/intermediate pressure accumulator; a first control valve mounted on said oil charging line to open or close the oil charging line; an oil feeding line branching from the oil charging line at a downstream position after the first control valve and connected to the oil suction line at a downstream position after the NC-type shuttle valve; and a second control valve mounted on said oil feeding line to open or close the oil feeding line such that the oil feeding line is opened during the ESP mode so as to feed the pressurized oil from the low/intermediate pressure accumulator to the inlet of said oil pump.