A Study of a Mechanical Continuous Variable Rocker Arm (VRA)

This paper presents the mechanism of a variable valve actuator that is called Variable Rocker Arm (VRA). The VRA the capability to control both valve event and valve lift. VRA is compact and simple. It consists of only two main components, an output cam and rocker arm. This could produce less movement and less inertia than other mechanisms. This mechanism can be applied to various valve trains, such as DOHC, SOHC, and Push rod. The VRA has been tested with a 4-stroke single cylinder engine to measure the torque, fuel consumption, and emissions. Besides controlling the valve event and valve lift, the VRA can also be operated with Variable Timing Control (VTC) if desired.