Fuel injector with a metering assembly having a seat molded to a polymeric support member

Abstract

A fuel injector is described that includes a polymeric housing, pole piece, filter assembly, coil assembly, spring member, armature assembly and metering assembly. The polymeric housing has a passageway extending between an inlet and an outlet along a longitudinal axis. The pole piece is disposed in the passageway. The metering assembly is secured to the polymeric housing proximate the outlet. The metering assembly has an 0-ring disposed between a seat molded to a polymeric support member. The polymeric support member includes a peripheral portion bonded to the polymeric housing proximate the outlet. A method of sealing a fuel injector outlet end is described.

1 . A fuel injector comprising: 
 a polymeric housing having a passageway extending between an inlet opening and an outlet opening along a longitudinal axis;    a pole piece disposed in the passageway, the pole piece having a through opening;    a filter assembly having a portion disposed in the through opening of the pole piece;    a coil assembly disposed in the polymeric housing to surround the pole piece;    a spring member disposed partly in the pole piece and including a spring portion contiguous with the portion of the filter assembly;    an armature assembly disposed in the passageway in a first position confronting the pole piece and in a second position contiguous to a portion of an end face of the pole piece, the armature assembly having a closure member; and    a metering assembly secured to the housing proximate the outlet, the metering assembly comprising a seat and a polymeric support member, the seat molded to the polymeric support member and the polymeric support member attached to the polymeric housing such that the polymeric support member supports the seat relative to the polymeric housing proximal to the outlet opening in the polymeric housing.    
     
     
         2 . The fuel injector of  claim 1 , wherein the seat comprises a metallic body having at least one annular flange molded to the polymeric support member.  
     
     
         3 . The fuel injector of  claim 2 , wherein the metallic body has first and second annular flanges spaced apart and about the longitudinal axis to define a pocket for retaining a sealing member between the seat and the polymeric support member.  
     
     
         4 . The fuel injector of  claim 1 , wherein the polymeric support member and the seat are insert-molded.  
     
     
         5 . The fuel injector of  claim 4 , wherein the seat comprises a metallic body.  
     
     
         6 . The fuel injector of  claim 5 , wherein the polymeric housing comprises a nylon member.  
     
     
         7 . The fuel injector of  claim 6 , wherein the polymeric support member comprises a nylon member.  
     
     
         8 . A method of making a metering assembly at an outlet of a fuel injector having a polymeric housing extending from an inlet to the outlet along a longitudinal axis, the method comprising: 
 molding a metering assembly comprising a seat and a polymeric support member for the seat, the seat including a peripheral portion molded to the polymeric support member; and    securing the polymeric support member to the polymeric housing such that the polymeric support member supports the seat relative to the polymeric housing proximal to the outlet in the polymeric housing.    
     
     
         9 . The method of  claim 8 , wherein the molding comprises insert-molding a metallic seat in a mold.