Hydraulic valve control system for internal combustion engines

Abstract

A modular hydraulic valve actuating assembly for use in association with a single combustion chamber in a multicylinder internal combustion engine cylinder head. The assembly includes a housing having a mounted surface to attach to the cylinder head immediately above a poppet valve. The housing includes a first cavity spaced from and oriented non-parallel to the poppet valve, a second cavity coaxially aligned with the poppet valve, and a fluid passageway extending between and hydraulically coupled to the first and second cavities. A master piston within the housing co-operates with a camshaft to define a first enclosed fluid chamber which varies in displacement as the master piston is reciprocally oscillated by the camshaft. A slave piston within the housing co-operates with the poppet valve to define a second enclosed fluid chamber hydraulically connected to the first and varying in displacement as the slave piston oscillates. A valve means within the housing regulates the flow of fluid from the pressurized master cylinder through an accumulator fluid port thereby automatically varying any one or more of valve lift, valve timing or duration of valve opening in response to an input signal at any point during engine operation.