Patent ID: 6557524
Filing Date: 2003-05-06
Classification: B60T,F02D,F02P,Y02T

Abstract:
An apparatus for controlling a negative pressure in an internal combustion engine, comprising:a brake booster that amplifies a pedal pressing force that is applied to a brake pedal, the brake booster using the negative pressure produced on a downstream side of a throttle valve provided in an intake passage of the internal combustion engine, as a power source for amplifying the pedal pressing force; and a controller that: determines whether the negative pressure applied to the brake booster has reached a predetermined level when the internal combustion engine is started; and if the negative pressure applied to the brake booster has not reached the predetermined level, increases an operating speed of the internal combustion engine to a predetermined high speed, and then keeps the throttle valve in a small opening state in which an opening amount of the throttle valve is smaller than that established when the internal combustion engine is in a fast idle state, during a period of time in which the internal combustion engine proceeds to a steady-state operating mode in which the internal combustion engine operates at a predetermined speed that is less than the predetermined high speed.