Fuel nozzle having a nozzle valve needle

In order to obtain a variety of injection fuel monitoring system can be used in a simple and space-saving structure, the fuel nozzles has a nozzle valve needle, the valve needle can be held in a closed position under the action of the spring, and by the pressure of the injected fuel is opened , the fuel nozzle has a control piston, the pressure may be applied or released through the pressure fluid pressure to the piston so that it moves to two different axial positions in one position, the piston can limit the opening stroke of the nozzle needle valve to open one or more rows of nozzle holes.