Patent ID: 6578536
Filing Date: 2003-06-17
Classification: F01L

Abstract:
A hydraulically operated valve system for an internal combustion engine having a cylinder bore, said system comprising:a high pressure source of fluid; a low pressure source of fluid; a first control valve assembly comprising a first stem valve moveable between open and closed positions and a first solenoid actuator having an armature element, the first control valve assembly being operably connected to the high pressure source of fluid; a second control valve assembly comprising a second stem valve moveable between open and closed positions and a second solenoid actuator having an armature element, the second control valve assembly being operably connected to the low pressure source of fluid; a cylinder valve adapted to selectively provide fluid access to said cylinder bore and being operably connected to the first and second control valve assemblies such that the cylinder valve moves into an open position when the first stem valve is in the open position and the second stem valve is in the closed position; the armature element of the first control valve being formed of a powder metal comprising a plurality of iron particles coated with an inorganic material.