Patent ID: 6129425
Filing Date: 2000-10-10
Classification: B60T

Abstract:
A device for judging a normal operation of a brake system of a vehicle such as an automobile having wheels, the brake system comprising wheel cylinders each applying a braking force to each corresponding one of the wheels by a supply of a pressurized brake fluid thereto, a brake pedal, and a master cylinder for generating the pressurized brake fluid according to a depression of the brake pedal by a driver, the device comprising:means for detecting a stroke of the depression of the brake pedal by the driver,means for detecting a pressure of the brake fluid pressurized by the master cylinder according to the depression of the brake pedal, andmeans for judging if the stroke detected by the stroke detection means and the pressure detected by the pressure detection means are correlated with one another within a range determined for a judgment of a normal operation of the brake system,wherein the device further comprisesat least one of means for detecting speed of change of the stroke detected by the stroke detection means and means for detecting speed of change of the pressure detected by the pressure detection means, andmeans for restraining the judgment means from making the judgment operation thereof based upon a standard range of the correlation between the stroke and the pressure when at least one of the stroke change speed and the pressure change speed is not smaller than a threshold value determined therefor.