Continuously Variable
Valve Timing (CVVT) system controls valve overlap by forcibly activating
the camshaft and adjusts EGR (Exhaust Gas Recirculation) amount. It
decreases exhaust gas (NOx, HC) and improves fuel economy, idle state,
torque in low speed and power in high speed. This system uses engine oil
pressure and consists of the two CVVT Oil Control Valves (OCV) in each
bank which supplies oil to cam phaser according to PWM (Pulse With
Modulation) signal of the PCM, a CVVT Oil Temperature Sensor (OTS) which
detects the oil temperature and a cam phaser which is installed on the end
of the camshaft and converts camshaft phase. The oil getting out of the
CVVT oil control valve flows into the cam phaser and rotates the rotor
inside camphaser. At this time, the camshaft rotates with the rotor and
the cam phase is changed.
| 1. |
When camshaft rotates engine rotation-wise:
Intake-Advance / Exhaust-Retard |
| 2. |
When camshaft rotates counter engine
rotation-wise: Intake- Retard / Exhaust- Advance
|
