Patent ID: 6254202
Filing Date: 2001-07-03
Classification: B60T

Abstract:
A vehicle braking apparatus on a vehicle capable of operating a brake cylinder with a hydraulic braking oil pressure produced by a master cylinder connected to a vacuum booster and a hydraulic braking oil pressure produced by a hydraulic pressure pump, comprising:normal mode braking means for operating the brake cylinder with the hydraulic braking pressure produced by said master cylinder;emergency mode braking means for operating the brake cylinder with the braking oil pressure increased by the hydraulic pressure pump when an insufficient braking force is obtained from the hydraulic braking pressure produced by said master cylinder;means for calculating a target deceleration of the vehicle based on an operating state of the vehicle, but without depending on an amount of brake operation conducted by a driver of the vehicle;said emergency mode braking means operates the brake cylinder when a target deceleration is at least a predetermined value;a vacuum sensor for detecting internal pressure in a vacuum system, whereby an abnormality in the pressure in the vacuum system may be determined from an output of said vacuum sensor; andwhen an abnormality is detected in said vacuum system, said brake cylinder is operated with said hydraulic braking pressure increased by said hydraulic pressure pump.