Patent ID: 8006659
Filing Date: 2011-08-30
Classification: F01L

Abstract:
1. An internal combustion engine with a mechanical variable valve mechanism that is positioned between a drive cam and a rocker arm, which is supported by a hydraulic lash adjuster and a valve, the internal combustion engine comprising: a lost motion spring which imposes a load so as to press the variable valve mechanism against the drive cam; and a valve spring which imposes a load so as to press the rocker arm against the variable valve mechanism; wherein, when a first engine speed is a critical engine speed at which the inertia force of the variable valve mechanism exceeds the maximum load on the lost motion spring and a second engine speed is a critical engine speed at which the inertia forces of the valve and the rocker arm exceed the maximum load on the valve spring, the maximum loads of the lost motion spring and the valve spring are set such that the first engine speed is lower than the second engine speed.