Mixer and doser cone assembly

Patent metadata

Field	Value
Publication number	US-2017191395-A1
Application number	US-201415315046-A
Country	US
Kind code	A1
Filing date	Jun 3, 2014
Priority date	Jun 3, 2014
Publication date	Jul 6, 2017
Grant date	—

Abstract

A vehicle exhaust system includes an exhaust component defining an engine exhaust gas passageway and which includes an opening. A doser defines a doser axis and extends to a doser tip that is configured to spray a reducing agent into the engine exhaust gas passageway through the opening. A cone has a base end positioned adjacent the opening such that an annular gap is formed within the exhaust component around the doser tip. Exhaust gas is directed into the base end of the cone through the annular gap in a direction transverse to the doser axis. This configuration reduces deposit formation while still allowing the reducing agent to be thoroughly mixed with engine exhaust gases prior to introduction of the mixture into a downstream exhaust component.

First claim

1 . A vehicle exhaust system comprising:
an exhaust component defining an engine exhaust gas passageway, the exhaust component including an opening; a doser defining a doser axis and extending to a doser tip that is configured to spray a reducing agent into the engine exhaust gas passageway through the opening; a cone having a base end positioned adjacent the opening such that an annular gap is formed within the exhaust component around the doser tip, and wherein the base end is arranged relative to the exhaust component to cause exhaust gas to be directed into the base end of the cone through the annular gap in a direction transverse to the doser axis during use of the vehicle exhaust system.

2 . The vehicle exhaust system according to claim 1 wherein the base end of the cone is arranged relative to the exhaust component to cause the exhaust gas to be directed into the base end of the cone in an evenly distributed manner about the annular gap in a direction that is perpendicular to the doser axis.

3 . The vehicle exhaust system according to claim 1 wherein the base end extends to a distal end, the distal end having a greater diameter than the base end.

4 . The vehicle exhaust system according to claim 1 including a housing fixed to the exhaust component and surrounding at least a portion of the cone, the housing including at least one slot formed to direct exhaust gas in a first direction against an outer surface of the cone during use of the vehicle exhaust system, the cone is spaced apart from the housing to cause the exhaust gas to flow in a second direction along the outer surface of the cone toward the base end during use of the vehicle exhaust system, and the base end spaced apart from the exhaust component to cause the exhaust gas to flow in a third direction to enter the annular gap during use of the vehicle exhaust system.

5 . The vehicle exhaust system according to claim 4 wherein the cone is shaped to cause the exhaust gas to flow in a fourth direction to exit the cone.

6 . The vehicle exhaust system according to claim 5 wherein the fourth direction extends generally along the doser axis.

7 . The vehicle exhaust system according to claim 5 wherein the third direction is perpendicular to the fourth direction.

8 . The vehicle exhaust system according to claim 1 wherein the cone is concentric with the doser axis.

9 . The vehicle exhaust system according to claim 1 wherein the exhaust component comprises a mixer.

10 . The vehicle exhaust system according to claim 9 wherein the opening is positioned downstream of an inlet baffle of the mixer.

11 . The vehicle exhaust system according to claim 10 further including a housing that surrounds the cone, the housing including a plurality of circumferentially spaced slots, and wherein the inlet baffle includes a primary opening configured to direct a majority of an exhaust gas stream through the mixer during use of the vehicle exhaust system and a plurality of openings configured to deviate a small portion of the exhaust gas stream toward the housing and through the slots against an outer surface of the cone during use of the vehicle exhaust system.

12 . The vehicle exhaust system according to claim 11 wherein the plurality of openings comprises at least three openings that are spaced apart from each other about an outer peripheral edge of the inlet baffle.

13 . The vehicle exhaust system according to claim 12 wherein the base end of the cone extends to a distal end of the cone, the distal end having a greater diameter than the base end, and wherein the annular gap is in fluid communication with the three openings and slots, the annular gap is formed to receive a flow only via the three openings and slots, and wherein the cone has a single exit via the distal end.

14 . A method for injecting a reducing agent into an exhaust component comprising the steps of:
providing an exhaust component defining an engine exhaust gas passageway, the exhaust component including an opening; mounting a doser to the exhaust component, the doser extending to a doser tip that is configured to inject a reducing agent along a doser spray axis and into the engine exhaust gas passageway through the opening; positioning a base end of a cone adjacent the opening such that an annular gap is formed within the exhaust component around the doser tip such that exhaust gas is directed into the base end of the cone through the annular gap in a direction transverse to the doser spray axis while reducing agent is injected into the engine exhaust gas passageway.

15 . The method according to claim 14 wherein the exhaust gas enters the annular gap in an evenly distributed manner about the doser spray axis.

16 . The method according to claim 15 further including fixing a housing to the exhaust component to surround at least a portion of the cone, the housing including at least one slot formed to direct the exhaust gas in a first direction against an outer surface of the cone, the cone is spaced apart from the housing to cause the exhaust gas to then flow in a second direction along the outer surface of the cone toward the base end, and the base end spaced apart from the exhaust component to cause the exhaust gas to then flow in a third direction to enter the annular gap.

17 . The method according to claim 16 wherein the cone is shaped to cause the exhaust gas to then flow in a fourth direction to exit the cone, after flowing through the annular gap.

18 . The method according to claim 17 wherein the fourth direction extends generally along the doser spray axis.

19 . The method according to claim 17 wherein the third direction is perpendicular to the fourth direction.

20 . The method according to claim 14 further including surrounding the cone with a housing that includes a plurality of circumferentially spaced slots, and wherein the exhaust component comprises a mixer including an inlet baffle, and further including forming the inlet baffle to include a primary opening that directs a majority of an exhaust gas stream through the mixer and a plurality of openings that deviate a small portion of the exhaust gas stream toward the housing and through the slots against an outer surface of the cone.

Assignees

• Faurecia Emissions Control Technologies Usa Llc

Inventors

• Alano Eduardo
• Dimpelfeld Philip M

Classifications

• F01N3/206

  Adding periodically or continuously substances to exhaust gases for promoting purification, e.g. catalytic material in liquid form, NOx reducing agents · CPC title

• F01N3/208 Primary

  Control of selective catalytic reduction [SCR], e.g. by adjusting the dosing of reducing agent · CPC title

• F01N3/20

  specially adapted for catalytic conversion (F01N3/22 takes precedence) · CPC title

• F01N3/2066 Primary

  Selective catalytic reduction [SCR] · CPC title

• B01D53/94

  by catalytic processes · CPC title