Variable valve device for an internal combustion engine

Abstract

A variable valve device has a configuration in which a first cam ( 20 ) and a second cam ( 22 a ) that is a counterpart of the first cam are disposed in the outside of a shaft member ( 17 ) so that the second cam ( 22 a ) is displaceable in the circumferential direction, and is formed so that a cam face ( 22 c ) of the second cam has a cam width dimension a that is larger than a cam width b of a cam face of the first cam.

1 . A variable valve device for an internal combustion engine, which varies valve phases of a pair of intake valves or valve phases of a pair of exhaust valves, which is provided to 2 of the shaft member to be displaceable in a circumferential direction and has a cam face that drives the other intake valve or the other exhaust valve; and
 a cam-phase changing mechanism that changes a phase of the second cam relative to the first cam,   wherein the cam face of the second cam is formed to have a cam width dimension that is larger than cam width of the cam face of the first cam.   
     
     
         2 . The variable valve device for an internal combustion engine according to  claim 1 , wherein:
 the shaft member is configured by pivotably fitting an inner camshaft into an outer camshaft made up of a pipe member;   the first cam is disposed in an outer periphery of the outer camshaft, and the second cam is disposed to be pivotable around an axis of the outer camshaft; and   a phase of the second cam is variable on the basis of the first cam in response to a relative displacement of the outer camshaft and the inner camshaft.   
     
     
         3 . The variable valve device for an internal combustion engine according to  claim 1 , wherein:
 the first cam is formed to have a cam width dimension that is larger than cam width of a camshaft having a cam that forms an integral part of a shaft member applied in an internal combustion engine of the same model.   
     
     
         4 . The variable valve device for an internal combustion engine according to  claim 2 , wherein:
 the first cam is formed to have a cam width dimension that is larger than cam width of a camshaft having a cam that forms an integral part of a shaft member applied in an internal combustion engine of the same model.