import com.greensock.*;

var xx:Number=0;

var myTimer:Timer = new Timer(1000, 0);

myTimer.addEventListener("timer", timerHandler);

myTimer.start();

function timerHandler(event:TimerEvent):void {

           xx+=20;

        TweenMax.to(mc, 1, {x:xx});

}

ease:Linear.easeNone