Patent ID: 8646422
Filing Date: 2014-02-11
Classification: F01L

Abstract:
1. An electro-hydraulic variable valve lift apparatus comprising: a housing; a driving cam; a pump piston which forms a main chamber with the housing, reciprocates within the housing according to rotation of the driving cam, and forms hydraulic pressure within the main chamber; a pump piston elastic portion disposed for elastically supporting the pump piston; an oil pressure controller communicating with the main chamber in order to control hydraulic pressure within the main chamber; a hydraulic piston slidably disposed within the housing, includes a first body having a first diameter and a second body having a second diameter larger than the first diameter, and is operably connected with a valve; and a piston guide disposed between the housing and the hydraulic piston for guiding the hydraulic piston; wherein: wherein the first body comprises: wherein the first hydraulic line is closed by the piston guide when the valve is closed.