Oliff & Berridge, PLC
Apparatus for controlling vacuum pressure in internal combustion engine
 Pressure in an air intake passage is changed according to an opening size of a throttle valve. The throttle valve is open when an engine performs a stratified charge combustion. The opening size of the throttle valve is selected based on a load applied to the engine when the engine performs a homogeneous charge combustion. A brake booster is connected to the intake passage and accumulates the pressure that is generated in the intake passage. The brake booster obtains braking force for the vehicle when the accumulated pressure is smaller than a predetermined reference value. The throttle valve is actuated by a controller to decrease the pressure in the intake passage when pressure in the brake booster detected by a pressure sensor is larger than the predetermined reference value. The reference value is corrected by the controller based on movement characteristics of the vehicle that is detected by velocity sensor. 
Toyota Jidosha Kabushiki Kaisha
F Y Y B B F F F F F F F F F F F F F
F02D Y02T Y02T B60T B60T F02D F02D F02D F02D F02D F02B F02M F02D F02D F02D F02D F02D F02D
inventional additional additional inventional inventional inventional inventional inventional inventional inventional additional additional additional additional additional additional additional inventional
Hiroyuki Yukio
Mizuno Yoshioka