Variable Valve Control Apparatus for Internal Combustion Engine

Abstract

A variable valve mechanism control apparatus ensures intake negative pressure in an idling state, decelerating state, coasting state, and a decelerating and coasting state, to operate accessories or a brake device with the ensured intake negative pressure. In the variable valve mechanism control apparatus of an internal combustion engine including a variable valve mechanism which changes the phase of an operating angle of an engine valve, and a control device which changes the phase of the variable valve mechanism, when the temperature of the internal combustion engine is greater than a certain value which can be treated as a post-warm-up state, the accelerator opening is less than a certain value which can be treated as an idling state, and the intake negative pressure is less than a predetermined value, the phase is changed to converge to a predetermined phase at which a predetermined intake negative pressure occurs.

1 . A variable valve mechanism control apparatus of an internal combustion engine, comprising:
 a variable valve mechanism which changes the phase of an operating angle of an engine valve; and   a control device which changes the phase of the variable valve mechanism, wherein in a case in which the temperature of the internal combustion engine is greater than a certain value which can be treated as a post-warm-up state, the accelerator opening is less than a certain value which can be treated as an idling state, and the intake negative pressure is less than a predetermined value, the phase is changed so as to converge to a predetermined phase at which a predetermined intake negative pressure occurs.   
     
     
         2 . A variable valve mechanism control apparatus of an internal combustion engine according to  claim 1 , wherein the variable valve mechanism is provided for an intake valve, and the predetermined phase at which a predetermined intake negative pressure occurs, is set at an intermediate advance angle position at which the intake negative pressure increases, and the intermediate advance angle position is defined by intake negative pressure reduction associated with intake blowback, which increases as the operating angle phase of the intake valve is delayed, and by intake negative pressure reduction associated with an increase in internal EGR according to valve overlap with an exhaust valve, which increases as the operating angle phase of the intake valve is advanced. 
     
     
         3 . A variable valve mechanism control apparatus according to  claim 1 , wherein the variable valve mechanism is provided for an intake valve, and the predetermined phase at which a predetermined intake negative pressure occurs, is set at the most advanced angle position of the operating angle phase of the exhaust valve, at which the intake negative pressure increases associated with a decrease in internal EGR according to valve overlap with the intake valve, which decreases as the operating angle phase of the exhaust valve is advanced.