Injector Closing
If the fuel injector is activated by the DDE, the piezo-element presses the control valve (2) down against the spring force via the coupler module (1) and closes the bypass (3). The fuel from the control volume (6) can then flow across the outlet (7) and the control valve.
The pressure in the control volume drops and the nozzle needle (4) is opened by the fuel delivery pressure.