Patent ID: 7841311
Filing Date: 2010-11-30
Classification: F01L

Abstract:
1. A variable valve timing device for an internal combustion engine, comprising: a gas exchange valve control shaft which has first and second concentrically arranged cam shafts that are adjustable in a rotatable manner with respect to each other, by which a cam of said first cam shaft is adjusted in terms of its angle towards a cam of said second cam shaft; a cam phasing device which operates by rotatable vanes provoking a swivelling relative movement between a driven member and an output member, the cam phasing device comprising at least two pivotable vane adjusters, each pivotable vane adjuster is assigned to one of the two cam shafts, and said pivotable vane adjusters are arranged axially one after the other in a direction of the gas exchange valve control shaft; said cam phasing device having only one drive pulley, said drive pulley comprising a sprocket adapted to be driven by a chain which can surround a crank shaft of said internal combustion engine; and said variable valve timing device having a side which is a near side of said first and second concentrically arranged cam shafts and a side which is a far side from said first and second concentrically arranged cam shafts and having a communication collar on said near side which bears conduits for intake and piping of a hydraulic fluid to each of two sets of hydraulic chambers of said first and said second pivotable vane adjuster; wherein said communication collar moves synchronously along with said drive pulley.