Patent ID: 6223708
Filing Date: 2001-05-01
Classification: F01L

Abstract:
An automatic decompression system for an internal combustion engine with at least one outlet valve and one inlet valve which are activated by a camshaft having at least one cam, and wherein said at least one outlet valve is lifted from its valve seat during starting to reduce cranking resistance, said system comprising:a fully automatic lifting device for lifting the at least one outlet valve at speeds below a switching speed for change over from compression to decompression, which fully automatic lifting device engages in the cam of the at least one outlet valve and effects lifting of the at least one outlet valve from its valve seat,wherein the fully automatic lifting device is equipped with a bow-shaped member pivoted in articulated relationship and disposed between the at least one cam and a cam disk, which bow-shaped member has two articulated arms pivoted at points in a radial plane of the cam disk and connected by a crosspiece,and wherein at engine speeds below the switching speed said bow-shaped member occupies in the cam plane an engaged decompression position, in which said bow-shaped member projects beyond the cam base circle, and when the switching speed is reached said bow-shaped member can be disengaged into a neutral position in the cam-disk, andwherein at least one flyweight is coupled to the bow-shaped member and biased by a spring in a radial direction to control the engagement and disengagement of the bow-shaped member depending on the engine speed.