VARIABLE VALVE TIMING MECHANISM [SKYACTIV-G 2.0]

id0110h2002000


Outline

•  Achieves optimum valve timing according to the driving conditions by the variable valve timing mechanism changing the phases of the crankshaft and camshaft.
•  An electric type variable valve timing mechanism on the intake side and a hydraulic pressure type on the exhaust side has been adopted. With the adoption of the variable valve timing mechanism on both sides of the intake and exhaust, the expansion of the valve opening angle and the accuracy of the intake and exhaust controls have been improved.
•  The electric variable valve timing mechanism obtains higher response than the hydraulic variable valve timing mechanism. As a result, expansion of overlap and the closing timing of the intake valve are achieved.

Structural View

am3uun00002434

Structure

Part name
Function
Hydraulic variable valve timing actuator
The phases of the exhaust camshaft and crankshaft are changed according to the hydraulic pressure.
Electric variable valve timing actuator
Receives the operation of the electric variable valve timing motor/driver to change the phases of the intake camshaft and crankshaft.
Electric variable valve timing motor/driver
Operates the electric variable valve timing actuator based on the signals from the PCM.
OCV
Operates according to the energization current from the PCM and switches the hydraulic passage to the hydraulic variable valve timing actuator.
Intake camshaft position sensor
Inputs the intake camshaft position signal to the PCM.
Exhaust camshaft position sensor
Inputs the exhaust camshaft position signal to the PCM.
Crankshaft position sensor
Inputs the crankshaft position signal to the PCM.


Operation


At engine start

•  Engine startability has been improved by utilizing the features of the operable electric variable valve timing even under the engine stop condition and controlling the optimal timing according to engine conditions.


Light/medium load range

•  Pumping loss is reduced by properly controlling the timing of intake and exhaust, improving the fuel consumption rate.


High load range

•  By properly controlling the timing of the intake and exhaust and using the effect of scavenging residual gas in the cylinder and the inertia charging effect, the volumetric efficiency and the output are improved.