Fuel injector and fuel system having integral filter supported in valve seat plate, and valve seat plate and filter assembly

Patent metadata

Field	Value
Publication number	US-2022282692-A1
Application number	US-202117191260-A
Country	US
Kind code	A1
Filing date	Mar 3, 2021
Priority date	Mar 3, 2021
Publication date	Sep 8, 2022
Grant date	—

Abstract

A fuel system for an internal combustion engine includes a pressurized fuel supply, and a fuel injector fluidly connected to the pressurized fuel supply. The fuel injector includes a valve seat plate forming a valve seat, an injection control valve, and a nozzle cavity. A filter, which can include a 2-dimensional filter, is positioned partially within the valve seat plate and partially within an injector body to filter an incoming flow of high-pressure fuel. The valve seat plate and filter are integrated in a valve seat plate and filter assembly.

First claim

What is claimed is:

1 . A fuel injector comprising:
an injector housing defining a longitudinal axis and having formed therein a high-pressure inlet, a nozzle supply cavity, a check control chamber, and nozzle spray orifices, and the fuel injector defining a low pressure space; a direct operated nozzle check movable between an advanced position blocking the nozzle spray orifices from the nozzle supply cavity, and a retracted position where the nozzle spray orifices are open; an injection control valve movable between a closed position blocking the check control chamber from the low pressure space, and an open position; the injector housing further including a valve seat plate having formed therein a valve seat contacted by the injection control valve at the closed position, and a supply passage, and each of the nozzle supply cavity and the check control chamber is fluidly connected to the high-pressure inlet by way of the supply passage; and a filter supported in the valve seat plate and positioned to filter an incoming flow of high-pressure fuel through the supply passage from the high-pressure inlet.

2 . The fuel injector of claim 1 wherein the injector housing further includes an injector body attached to a nozzle case, and the valve seat plate is clamped between the injector body and the nozzle case and the filter projects from the valve seat plate into the injector body.

3 . The fuel injector of claim 2 wherein a clearance extends circumferentially around the filter between the filter and the injector body, and axially between the filter and the injector body.

4 . The fuel injector of claim 3 wherein an inlet passage is formed in the injector body and includes an incoming portion extending from the high-pressure inlet, and an outgoing void portion extending from the incoming portion to the supply passage and diametrically enlarged relative to the incoming portion.

5 . The fuel injector of claim 4 wherein the filter includes an outlet end interference-fitted with the valve seat plate within the supply passage, and an opposite second end within the injector body.

6 . The fuel injector of claim 4 wherein the filter includes a 2-dimensional filter.

7 . The fuel injector of claim 2 wherein the injector housing further includes a nozzle sleeve clamped between the valve seat plate and the nozzle case, and the nozzle sleeve includes a top land forming an axial stop positioned to limit axial displacement of the filter.

8 . The fuel injector of claim 6 wherein the injector housing further includes an orifice piece clamped between the valve seat plate and the nozzle sleeve, and the orifice plate having formed therein a fill orifice extending between the nozzle supply cavity and the check control chamber and fluidly connecting the high-pressure inlet to the check control chamber.

9 . A fuel system for an internal combustion engine comprising:
a pressurized fuel supply; a fuel injector defining a longitudinal axis and including an injector body having formed therein a high-pressure inlet fluidly connected to the pressurized fuel supply, and a direct operated nozzle check having a closing hydraulic surface exposed to a fluid pressure of a control chamber; the fuel injector further including a valve seat plate forming a valve seat, and an injection control valve movable from a closed position in contact with the valve seat, to an open position, to open the direct operated nozzle check, and a nozzle cavity; and a filter positioned partially within the valve seat plate and partially within the injector body to filter an incoming flow of high-pressure fuel.

10 . The fuel system of claim 9 wherein the filter includes an outlet end interference-fitted with the valve seat plate, and an opposite second end clearance-fitted within the injector body.

11 . The fuel system of claim 10 wherein a clearance extends circumferentially around the filter between the filter and the injector body, and axially between the filter and the injector body.

12 . The fuel system of claim 9 wherein the filter includes a 2-dimensional filter.

13 . The fuel system of claim 9 wherein the fuel injector further includes a nozzle sleeve, and the nozzle sleeve includes a top land forming an axial stop positioned to limit axial displacement of the filter.

14 . The fuel system of claim 13 wherein the fuel injector further includes an orifice piece having a fill orifice fluidly connecting the nozzle cavity to the control chamber, and a drain orifice formed fluidly between the check control chamber and the valve seat.

15 . The fuel system of claim 14 wherein the orifice piece is separate from the valve seat plate and clamped between the valve seat plate and the nozzle sleeve.

16 . The fuel system of claim 9 wherein:
a supply passage is formed in the valve seat plate, and the filter is within the supply passage; and
an inlet passage is formed in the injector body and includes an incoming portion extending from the high-pressure inlet, and an outgoing void portion extending from the incoming portion to the supply passage, and the outgoing portion is diametrically enlarged relative to the incoming portion and the filter projects into the void portion.

17 . A valve seat plate and filter assembly for a fuel injector in a fuel system comprising:
a valve seat plate defining a center axis extending between a first axial seat plate side and a second axial seat plate side; a valve seat formed on the first axial seat plate side; a control pressure drain passage centered about the center axis and extending between the first axial seat plate side and the second axial seat plate side to fluidly connect a check control chamber to the valve seat; a supply passage spaced radially outward of the control pressure drain passage and extending between the first axial seat plate side and the second axial seat plate side; and a filter supported in the supply passage and projecting from the first axial seat plate side.

18 . The assembly of claim 17 wherein the filter includes a 2-dimensional filter.

19 . The assembly of claim 18 wherein the filter includes an outlet end formed adjacent to the second axial seat plate side, and an opposite second end located outside of the valve seat plate.

20 . The assembly of claim 19 wherein:
a first raised sealing surface is formed on the first axial seat plate side and extends circumferentially around the valve seat;
a second raised sealing surface is formed on the first axial seat plate side and extends circumferentially around the supply passage and the filter; and
a third raised sealing surface is formed on the first axial seat plate side, and a plurality of dowel holes originate on the first axial seat plate side within the third raised sealing surface and extend to the second axial seat plate sides.

Assignees

• Caterpillar Inc

Inventors

• Bannur Nagaraja Manjunath
• Tower Benjamin Ray
• Tatikonda Venkata R
• Hill Adam Charles

Classifications

• F02M61/1886

  Details of valve seats not covered by groups F02M61/1866 - F02M61/188 · CPC title

• F02M61/165 Primary

  Filtering elements specially adapted in fuel inlets to injector · CPC title

• F02M61/1866

  Valve seats or member ends having multiple cones · CPC title

• F02M61/12

  characterised by the provision of guiding or centring means for valve bodies · CPC title

• F02M37/0047

  Layout or arrangement of systems for feeding fuel (fuel injection apparatus characterised by their conduits and venting means F02M55/00; fuel injection apparatus having a common rail F02M63/0225; arrangement of fuel conduits of low pressure fuel injection apparatus F02M69/462) · CPC title