Patent ID: 6516760
Filing Date: 2003-02-11
Classification: F01L

Abstract:
A timing system for internal combustion engines for motor vehicles, comprisingat least one distribution shaft provided with cam means, at least one suction or exhaust valve operated by said cam means, and control means for providing variable lifts and timings of said valve, in which between said cam means and the valve there is arranged a hydraulic tappet including a cup member and a piston delimiting therebetween a chamber that communicates with inlet passage means for feeding oil form a hydraulic circuit, wherein closure of said inlet passage means is performed by said cup member as a result of displacement thereof towards said piston operated by said cam means, and wherein the position of said inlet passage means is selectively regulated to correspondingly vary the moment at which said inlet passage means becomes closed by said cup member and, consequently, retard or advance the opening of said valve to decrease or increase the lift thereof, respectively.