Device for purifying the exhaust gas of an internal combustion engine

Patent metadata

Field	Value
Publication number	US-10030564-B2
Application number	US-201414912675-A
Country	US
Kind code	B2
Filing date	Aug 29, 2014
Priority date	Aug 30, 2013
Publication date	Jul 24, 2018
Grant date	Jul 24, 2018

Abstract

This exhaust gas purification device ( 2, 102 ), comprising an upstream pipe ( 4 ), in which a first exhaust gas purification member ( 6 ) is housed, a downstream pipe ( 8 ) in which a second exhaust gas purification member ( 10 ) is housed, a mixing chamber ( 12 ) and an injection device ( 20 ) for a nitrogen oxide reducing product;
is characterized in that the mixing chamber includes a first deflector member capable of channeling the flow of exhaust gas such that it flows through the jet of nitrogen oxide reducing product substantially perpendicular to the second deflector member ( 36, 56 ), the second deflector member being configured to form two swirling flows of a mixture of exhaust gas and nitrogen oxide reducing product; and in that the device further includes an element ( 54, 58 ) for protecting the second member ( 10 ) for purifying exhaust gas.

First claim

The invention claimed is:

1. An exhaust gas purification device comprising:
an upstream pipe in which is housed a first exhaust gas purification member for purifying exhaust gas;
a downstream pipe in which is housed a second exhaust gas purification member for purifying exhaust gas;
a mixing chamber comprising a lateral wall defining an exhaust gas inlet communicating with the upstream pipe and an exhaust gas outlet communicating with the downstream pipe;
an injection device able to inject, in the mixing chamber, at least one jet of a nitrogen oxide reducing product in an injection direction;
wherein that the mixing chamber includes a first deflector member and a second deflector member, the first deflector member being capable of channeling the flow of exhaust gas such that exhaust gas flows through the jet of nitrogen oxide reducing product in a deflected direction forming, with the injection direction, an angle close to 90°, then substantially perpendicular to the second deflector member, the second deflector member being configured to form two swirling flows of a mixture of exhaust gas and nitrogen oxide reducing product on either side of the jet of nitrogen oxide reducing product; and
a protection element that protects the second exhaust gas purification member, the protection element extending in front of the jet of nitrogen oxide reducing product to intercept the at least one jet of a nitrogen oxide reducing product injected along the injection direction.

2. The device according to claim 1 , wherein the jet of nitrogen oxide reducing product is positioned downstream from the first deflector member and upstream from the second deflector member.

3. The device according to claim 1 , wherein the mixing chamber includes two volumes situated across from the second deflector member, on either side of the first deflector member, the two volumes being able to receive the two swirling flows of the mixture of exhaust gas and nitrogen oxide reducing product.

4. The device according to claim 1 , wherein the mixing chamber includes an upstream part in which the inlet emerges, the flow of exhaust gas flowing along the upstream part in an upstream direction, the first deflector member being arranged so that the deflected direction forms an angle comprised between 45° and 135° with the upstream direction.

5. The device according to claim 4 , wherein the injection direction is substantially parallel to the upstream direction.

6. The device according to claim 1 , wherein the protection element is formed by the first deflector member.

7. The device according to claim 1 , wherein the protection element comprises a plate having a half-moon shape.

8. The device according to claim 7 , wherein the plate further includes two protruding tabs extending from a circumference of the plate.

9. The device according to claim 1 , wherein the second deflector member is formed by the lateral wall of the mixing volume.

10. The device according to claim 1 , wherein the second deflector member is formed by a second deflector wall positioned between the jet of nitrogen oxide reducing product and the lateral wall, downstream from the jet of nitrogen oxide reducing product.

11. The device according to claim 10 , wherein the second deflector wall has a wavy shape having a central portion protruding toward the jet of nitrogen oxide reducing product and two recessed portions situated on either side of the central portion.

12. The device according to claim 11 , wherein the first deflector member is arranged to deflect the flow of exhaust gas toward the central portion of the second deflector wall.

13. The device according to claim 1 , wherein the jet of nitrogen oxide reducing product flows substantially parallel to the second deflector member.

14. The device according to the claim 1 , wherein the first exhaust gas purification member comprises an oxidation catalyst and in that the second exhaust gas purification member comprises a catalyst for selective reduction of the nitrogen oxides and/or a catalyst for selective reduction of the nitrogen oxides with filter.

15. The device according to the claim 1 , wherein the two swirling flows are separated from one another and have respective axes of rotation parallel to one another and separated from one another.

16. The device according to the claim 1 , wherein the second deflector member is placed in an extension of the exhaust gas flow in the deflected direction.

17. The device according to the claim 1 , wherein the protection element is situated downstream from the second deflector member.

18. The device according to the claim 1 , wherein the first deflector member, the second deflector member, and the protection element are arranged to form a U-shaped flow path for the exhaust gases around the first deflector member.

19. The device according to claim 18 , wherein the second deflector member forms a bottom of the U-shaped flow path.

20. The device according to claim 1 , wherein the protection element is a plate substantially parallel to the deflected direction.

21. The device according to claim 1 , wherein the protection element is positioned between the injection device and the second deflector member along the injection direction such that the protection element provides an injection surface facing the injection device and configured to intercept the nitrogen oxide reducing product.

22. The device according to claim 1 , wherein the second deflector member comprises a surface that receives flow deflected by the first deflector member and which is configured to form a first swirling flow of a mixture of exhaust gases and nitrogen oxide reducing product on one side of the jet and a second swirling flow of the mixture of exhaust gases and nitrogen oxide reducing product on another side of the jet.

23. The device according to claim 22 , wherein the surface of the second deflector member is formed by a wall having a wavy shape with a central portion protruding toward the injection device and two recessed lateral portions situated on either side of the central portion.

24. The device according to claim 22 , wherein the surface of the second deflector member is formed by a wall having a convex or concave shape.

25. The device according to claim 24 , wherein the surface of the second deflector member is formed by a wall having the concave shape, and wherein the concave shape faces the jet.

26. The device according to claim 25 , including a separating member fixed to the second deflector member to facilitate formation of the first and second swirling flows.

27. The device according to claim 24 , wherein the surface of the second deflector member is formed by a wall having the convex shape, and wherein the convex shape faces the jet.

Assignees

• Faurecia Systemes Dechappement

Inventors

• Cossard Sebastien
• Guilbaud Frederic

Classifications

• B01D2258/012

  Diesel engines and lean burn gasoline engines · CPC title

• B01D2259/124

  Liquid reactants · CPC title

• F01N3/2066

  Selective catalytic reduction [SCR] · CPC title

• 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

• F01N2610/1453

  Sprayers or atomisers; Arrangement thereof in the exhaust apparatus · CPC title