Fuel injector

A fuel injector comprising:

• a core,
• a valve disposed at a downstream side of the core, the valve having an armature on one end and a hole closing element on the other end, and
• a solenoid coil for attracting the valve toward the core, wherein an upstream end surface of the armature contacts a downstream end surface of the core when the solenoid coil is excited, wherein the hole closing element closes a fuel injection hole of a valve seat when the solenoid coil is not excited, and
• wherein at least one of the upstream end surface of the armature and the downstream end surface of the core is plated, and the thickness of the plating layer varies in a radial direction, and the upstream end surface of the armature and the downstream end surface of the core are made to be approximately parallel without the plating.

A fuel injector comprising:

• a core,
• a valve disposed at a downstream side of the core, the valve having an armature on one end and a hole closing element on the other end, and
• a solenoid coil for attracting the valve toward the core, wherein an upstream end surface of the armature contacts a downstream end surface of the core when the solenoid coil is excited, wherein the hole closing element closes a fuel injection hole of a valve seat when the solenoid coil is not excited, and
• wherein at least one of the upstream end surface of the armature and the downstream end surface of the core is partially plated at any position in a radial direction, and the upstream end surface of the armature and the downstream end surface of the core are made to be approximately parallel without the plating.