Apparatus for controlling negative pressure in internal combustion engine

摘要

An improved apparatus for controlling brake force of a vehicle is disclosed. A throttle valve (23) is closed for generating the negative pressure that is supplied to a brake booster (71). The brake booster is actuated to increase brake force acting on the vehicle when a difference between air pressure and the negative pressure is smaller than a predetermined magnitude. An electric control unit (ECU) (30) actuates the throttle valve to increase the absolute magnitude negative pressure when the ECU determines the differential pressure is smaller than the predetermined magnitude. The ECU corrects the magnitude of the negative pressure with a mapped value based on the computed magnitude.