developed by Toyota VVT-iE motor-driven intelligent variable valve timing system. VVT-i conventional hydraulic oil pressure is low due to poor lubrication and does not operate at low temperatures or low speed, so that the motor-driven VVT-i as compared to the hydraulic system in the form of VVT-i, the response speed of VVT-iE more motor control faster, more precise control, but also to achieve stepless adjustment.
1.VVT-iE system components
VVT-iE camshaft control system motor assembly, consisting of the crankshaft position sensor, cam shaft position sensor and VVT sensors.
control cam motor assembly controlling the motor, cycloid decelerating mechanism, spiral coil, and connection means composed of the camshaft timing sprocket.
2.VVT-iE works
When the timing advance control, motor speed is higher than the control cam of the camshaft, the spiral disk driven by a motor via a reduction mechanism, the control pin is connected to the disc along the spiral groove inside the sliding groove, the connecting mechanism in the direction of rotation of the camshaft disc in advance. When the timing delay control, the camshaft motor speed control slower than the rotational speed of the camshaft, the spiral disk driven by a motor via a reduction mechanism, connected to the control pin slides along the helical coil to the outside groove, means that the direction of the connection plate toward the delayed rotation of the camshaft . When the motor speed and the camshaft speed is the same, the coil plate does not rotate, no movement of the control pin is connected, the valve timing is not changed.
3.VVT-iE advantages system
developed by Toyota VVT-iE motor-driven variable valve timing intelligent when the system. VVT-i conventional hydraulic oil pressure is low due to poor lubrication and does not operate at low temperatures or low speed, the driving of the hydraulic type VVT-i and V form the motorVT-i system compared to the scope of work VVT-iE system expanded. VVT-iE can be changed at higher engine speeds and cold fluid temperature range, but timing of intake and exhaust valves, intake and exhaust efficiency increase to improve the stability of idling and low-speed stability, and improve the engine output torque, reduced part-load fuel consumption and improve emissions.
