Valve gear device for internal combustion engines

Claim 1

A valve gear device for internal combustion engines comprising: a stem connected to an intake or exhaust valve which opens or closes an intake or exhaust bore, respectively, that opens into a combustion chamber of an internal combustion engine; urging means for urging said stem to maintain said intake or exhaust valve in a closed state; a cam provided on a cam shaft; and a valve deactivating mechanism provided between said cam and said stem, wherein said valve deactivating mechanism comprises: a cylinder bore defined in a cylinder head of said internal combustion engine and extending along an axial direction of said intake or exhaust valve; a movable member movably engaged within said cylinder bore and operatively contacting said cam; a relative movement regulating means for one of engaging and disengaging said stem with said movable member, said regulating means being operatively positioned to move across an axial center of said stem so as to one of prevent and allow, respectively, relative movement between said movable member and said stem; an oil pressure supplying and discharging means for one of supplying and discharging oil pressure for said relative movement regulating means so as to one of engage and disengage said regulating means, respectively; and a valve means for controlling a flow of oil between said oil pressure supplyling and discharging means and said relative movement regulating means, wherein the flow of oil through said valve means allows movement of said relative movement regulating means after said movable member returns to an initial position after said movable member moves downwardly and then upwardly relative to said stem based on movement of said cam.