Patent ID: 9441589
Filing Date: 2016-09-13
CPC Classification: F02M,Y02T

Claim Text:
1. A fuel injector, comprising: a valve seat having a fuel injection hole; a body have a fuel path, wherein the valve seat is attached to a downstream side of the body; a valve; a movable armature provided in the valve; and a core having a fuel path, the core being disposed at an upstream side of the armature with a clearance, wherein the valve seat includes a first surface facing the valve, the valve includes a second surface facing the first surface of the valve seat, one of the valve seat and the valve includes a seal member attached to the first surface or the second surface, the seal member being disposed between the valve seat and the valve, one of the first and second surfaces includes a first portion and a protruding portion protruding toward the other of the first and second surfaces relative to the first portion, the other of the first and second surfaces includes a contact portion and a noncontact portion, the contact portion being configured to contact the protruding portion, the noncontact portion being configured to be noncontact with the protruding portion, and the contact portion and the noncontact portion being disposed on a same plane, when the valve is in the first position, the seal member contacts both of the valve seat and the valve around the fuel injection hole and seals a clearance between the valve and the valve seat, and the contact portion contacts the protruding portion, when the valve is in the second position, the seal member separates from the other of the valve seat and the valve, and the contact portion separates from the protruding portion, and surface hardness of the protruding portion is lower than surface hardness of the contact portion, the valve and the armature are disposed within the body and between the valve seat and the core, the valve is disposed at the downstream side of the body and the armature is disposed at the upstream side of the body, a sliding surface of the armature, which contacts and slides relative to the body, includes a surface hardened layer exposed at the sliding surface, and an end surface of the armature on a core side does not have a surface hardened layer, and a raw material of the armature is exposed at the end surface, the surface hardened layer of the sliding surface comprises a nitride layer and a diamond like carbon layer disposed on the nitride layer.