摘要 |
A discrete lift, variable timing (DLVT) engine valve control system for an internal combustion engine includes a plurality of electrohydraulic valves. The plurality of electrohydraulic valves are operable between at least an open and closed position. Each of the plurality of electrohydraulic valves is operable independently of the other of the plurality of electrohydraulic valves. In one preferred embodiment, a selected combination of the plurality of electrohydraulic valves are selectively operated between at least the open and closed positions to move a selected combination of a plurality of pistons disposed in a selected combination of a plurality of axially spaced cylinders positioned serially one on top of the other. In an alternative preferred embodiment, a selected combination of the plurality of electrohydraulic valves are selectively operated between at least the open and closed positions to open a selected combination of longitudinally spaced exhaust ports communicating with a cylinder. Methods for controlling an engine valve in an internal combustion engine also are provided.
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