Patent ID: 9657606
Date: 2017-05-23
CPC Classifications: F01L

Claim:
1. A cylindrical direct-acting valve lifter of an internal combustion engine with a variable lift mechanism which can switch between a high lifter comprising a high lift cam sliding surface with which a high lift cam comes into slidable contact and low lifter comprising a low lift cam sliding surface with which a low lift cam comes into slidable contact, wherein; the high lift cam sliding surface and the low lift cam sliding surface are integrally formed with an upper surface of the valve lifter and are formed as inclined surfaces whose surface roughness is smooth; each of the inclined surfaces of the cam sliding contact surfaces is formed by a flat surface inclined with respect to a plane perpendicular to a reciprocating direction of the valve lifter and a cam slide starting point on the cam sliding contact surface that is the inclined surface is positioned to be lower than a cam slide terminating point thereon; and the high lift cam and the low lift cam come into point contact with a cam slide starting point on the cam sliding contact surface that is higher than a center of the cam sliding contact surface, the high lifter and the low lifter rotate due to friction resistance generated by a rotation of the high lift cam and the low lift cam, the cam slide starting point is arrived to a lower position on the cam sliding contact surface and the rotation of the high lift cam and the low lift cam stops, and the high lift cam and the low lift cam moves along the inclined surface of the cam sliding contact surface to the cam slide terminating point that is higher than the cam slide starting point.