Deep pocket seat assembly in modular fuel injector having a lift setting assembly for a working gap and methods

A fuel injector for use with an internal combustion engine, the fuel injector comprising:

• an independently testable power group subassembly connected with an independently testable valve group subassembly so as to form a single unit;
• the power group subassembly having a first connector portion and including:
• an electromagnetic coil;
• a housing surrounding at least a portion of the coil;
• at least one terminal electrically coupled to the coil to supply electrical power to the coil;
• and
• at least one overmold formed over at least a portion of the coil and housing, the overmold having a first overmold end and a second overmold end opposite the first overmold end, the overmold defining an interior surface;
• the valve group subassembly having a second connector portion and including:
• a tube assembly having at least a portion engaged with the interior surface of the overmold, the tube assembly having an outer surface and a longitudinal axis extending between a first tube end and a second tube end, the tube assembly including:
• an inlet tube having a first inlet tube end and a second inlet tube end;
• a non-magnetic shell extending axially along the longitudinal axis and having a first shell end and a second shell end;
• a pole piece having at least a first portion connected to the inlet tube and a second portion connected to the first shell end thereby coupling the first shell end to the inlet tube;
• a valve body coupled to the second shell end;
• and
• an armature assembly disposed within the tube assembly substantially circumscribed by the electromagnetic coil, the armature assembly being displaceable along the longitudinal axis upon supplying energy to the electromagnetic coil, the armature assembly having a first armature end confronting the pole piece and a second armature end, the first armature end having a ferromagnetic portion and the second armature end having a sealing portion, the armature assembly further defining a through bore and at least one aperture in fluid communication with the through bore;
• a member disposed and configured to apply a biasing force against the armature assembly toward the second tube end;
• an adjusting tube disposed within the tube assembly proximate the second tube end;
• a filter assembly having a filter element, at least a portion of the filter assembly disposed within the inlet tube;
• a lift setting device disposed within the valve body to set the axial displacement of the armature assembly;
• and
• a seat assembly disposed in the tube assembly proximate the second tube end such that at least a portion of the seat assembly is disposed within the valve body, the seat assembly including:
• a flow portion, the flow portion extending along the longitudinal axis between a first surface and a second surface at a first length, the flow portion having at least one orifice defining a central axis and through which fuel flows into the internal combustion engine;
• and
• a securement portion having an outer surface, the securement portion extending distally along the longitudinal axis from the second surface at a second length at least as long as the first length.