Patent ID: 7354116

Claim:
A vehicle brake hydraulic pressure generating device comprising a hydraulic pressure source for generating a predetermined hydraulic pressure, a stroke simulator comprising a simulator piston operatively coupled with a brake operating member and an elastic member for imparting a stroke corresponding to a brake operating force to said simulator piston, an input piston having said simulator piston therein and displaceable under the brake operating force transmitted thereto from said simulator piston through said elastic member, a pressure adjusting valve displaceable under a pushing force transmitted from said input piston when said input piston is displaced under the brake operating force to adjust the hydraulic pressure supplied from said hydraulic pressure source to a value corresponding to the brake operating force, an auxiliary piston in which said pressure adjusting valve is received, a master cylinder defined forwardly of said auxiliary piston and activated by the output hydraulic pressure of said pressure adjusting valve, and a housing in which said stroke simulator, said input piston and said auxiliary piston are received, wherein the hysteresis of said stroke simulator while said hydraulic pressure source is functioning normally is set such that the output hydraulic pressure of said master cylinder for the stroke of said simulator piston while the brake operating force is increasing is higher than the output hydraulic pressure of said master cylinder for the stroke of said simulator piston while the brake operating force is decreasing.