Fuel injector for internal combustion engine, has control valve with control piston that operates on valve seat, where control piston exhibits pressure surface, which exposes closure area that is supplied with system pressure

摘要

The injector has a nozzle needle (19) with a control valve (18), which is actuated by an actuator (17) in particular piezo-actuator. The valve controls a control area (20) of the needle. The valve has a control piston (40) that operates on a valve seat. The control area is activatable and deactivatable at a low pressure area (46), so that the needle is lifted by the valve seat and the fuel is injected with system-pressure that lies in a needle pressure area (23). The piston exhibits a pressure surface (53), which exposes a closure area (50) that is supplied with the system pressure.