Patent ID: 7016780

Claim:
An internal combustion engine comprising: at least one combustion chamber; at least one injector to inject fuel directly into the combustion chamber; at least one piezoactuator; and a control unit for operating an internal combustion engine, including: a computer program executable on a computer of the control unit, including: computer program code for performing a method for operating an internal combustion engine in which fuel is injected directly into a combustion chamber by an injector that has a piezoactuator, the method including: determining an electrical charge, which is at least one of conveyed to and removed from the piezoactuator, by a process that is calibrated at least once during an operating time span of the internal combustion engine; wherein the process for determining the electrical charge at least one of transferred to and removed from the piezoactuator is calibrated during at least one triggering off-time of the piezoactuator while the internal combustion engine is operating; wherein the computer program is stored at a memory of the control unit, and wherein the control unit is one of an open-loop unit and a closed-loop unit.