Patent attributes
A fuel injection device has a nozzle body formed with an injection hole for injecting fuel and a nozzle needle reciprocating in the nozzle body to open and to close the injection hole. The nozzle needle has a sliding portion capable of moving in the nozzle body in a sliding manner, an insertion portion, of which diameter is smaller than that of the sliding portion, and a pressure receiving portion connecting the sliding portion with the insertion portion. The nozzle body has a guide portion for slidably holding the sliding portion and a fuel sump chamber formed on the injection hole side of the guide portion. The insertion portion is inserted through the fuel sump chamber. A clearance decreasing toward the fuel sump chamber is provided between the guide portion and the sliding portion.
