System Description

Fig 1: Identifying VVEL System Components

Courtesy of NISSAN NORTH AMERICA, INC.

VVEL actuator motor	VVEL control shaft position sensor	Ball screw nut
Ball screw shaft	Rocker arm	Link A
Control shaft	Eccentric cam	Drive shaft
Valve lifter	Intake valve	Link B
Output cam

VVEL (Variable Valve Event & Lift) is a system that controls valve event and valve lift continuously. Rotational movement of the drive shaft equipped with eccentric cam is transmitted to output cam via the rocker arm and two kinds of links to depress the intake valve. ECM decides the target valve lift according to the driving condition and sends the command signal to the VVEL control module. The VVEL control module controls the rotation of the control shaft using the VVEL actuator motor and changes the movement of the output cam by shifting the link supporting point. As a result, valve lift changes continuously to improve engine output and response.