METHOD FOR PERFORMING A CHARGE EXCHANGE IN AN INTERNAL COMBUSTION ENGINE

摘要

A method and system for perform a charge exchange in internal combustion engine comprising an additional intake and exhaust valve lifts performed during positive pressure gradients between the intake and exhaust systems to reducing scavenging losses and increase torque during low engine speeds.

主权项

1. A system for performing a charge exchange in an internal combustion engine comprising:
at least one cylinder head with at least one cylinder, each cylinder having at least one inlet opening for the supply of fresh air via an intake system and having at least one outlet opening for discharging the exhaust gases via an exhaust-gas discharge system and having a piston which is movable along a piston longitudinal axis between a bottom dead center and a top dead center, and at least two valve drives with at least two valves which are movable along their longitudinal axis between a valve closed position and a valve open position, performing a maximum valve lift, in order to open up and block the at least one inlet opening and the at least one outlet opening of the at least one cylinder during the course of a charge exchange, and having at least two actuating devices for opening the valves counter to a preload force, wherein the inlet valve of the at least one inlet opening is actuated to perform an additional valve lift before the piston, during the course of the charge exchange, reaches top dead center and before the inlet valve, during the course of the charge exchange, performs the maximum valve lift, and
the outlet valve of the at least one outlet opening is actuated to perform an additional valve lift before the piston, during the course of the charge exchange, reaches bottom dead center and after the outlet valve, during the course of the charge exchange, has performed the maximum valve lift.