EXHAUST GAS COOLER AND EXHAUST GAS RECIRCULATION SYSTEM WITH AN EXHAUST GAS COOLER

Abstract

An exhaust gas cooler (10) comprises at least one exhaust gas channel (16) defined by at least one wall that, at the inlet (12), comprises at least one edge substantially perpendicular to the direction of flow, and is distinguished thereby that at least one edge is covered by a cap (22) defining an air gap toward the edge.

An exhaust gas recirculation system comprises at least one such exhaust gas cooler.

Claims

1.-9. (canceled)

10. An exhaust gas cooler with at least one exhaust gas channel defined by at least one wall which comprises at the inlet at least one edge substantially perpendicular to the direction of flow, wherein at least one edge is covered by a cap which defines an air gap toward the edge.

11. An exhaust gas cooler according to claim 10, wherein at least one cap has at least one maximal extent perpendicular to the direction of flow, which corresponds to a width of the wall perpendicular to the direction of flow and/or a distance between two exhaust gas channels perpendicular to the direction of flow.

12. An exhaust gas cooler according to claim 10, wherein at least one cap is plugged onto two adjacent walls of exhaust gas channels.

13. An exhaust gas cooler according to claim 10, wherein one end directed toward the direction of at least one cap is implemented to be rounded.

14. An exhaust gas cooler according to claim 10, wherein at least one cap in its course in the direction of flow comprises at least one obliquity and/or one stage.

15. An exhaust gas cooler according to claim 10, wherein at least one cap is implemented of a metal, in particular of sheet steel.

16. An exhaust gas cooler according to claim 10, wherein at least one cap comprises at least one securement tab.

17. An exhaust gas cooler according to claim 10, wherein at least one cap is soldered or welded onto two adjacent walls of exhaust gas channels.

18. An exhaust gas recirculation system with at least one exhaust gas cooler according to claim 10.

19. An exhaust gas cooler according to claim 11, wherein at least one cap is plugged onto two adjacent walls of exhaust gas channels.

20. An exhaust gas cooler according to claim 11, wherein one end directed toward the direction of at least one cap is implemented to be rounded.

21. An exhaust gas cooler according to claim 12, wherein one end directed toward the direction of at least one cap is implemented to be rounded.

22. An exhaust gas cooler according to claim 11, wherein at least one cap in its course in the direction of flow comprises at least one obliquity and/or one stage.

23. An exhaust gas cooler according to claim 12, wherein at least one cap in its course in the direction of flow comprises at least one obliquity and/or one stage.

24. An exhaust gas cooler according to claim 13, wherein at least one cap in its course in the direction of flow comprises at least one obliquity and/or one stage.

25. An exhaust gas cooler according to claim 11, wherein at least one cap is implemented of a metal, in particular of sheet steel.

26. An exhaust gas cooler according to claim 12, wherein at least one cap is implemented of a metal, in particular of sheet steel.

27. An exhaust gas cooler according to claim 13, wherein at least one cap is implemented of a metal, in particular of sheet steel.

28. An exhaust gas cooler according to claim 14, wherein at least one cap is implemented of a metal, in particular of sheet steel.

29. An exhaust gas cooler according to claim 11, wherein at least one cap comprises at least one securement tab.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0021] In the following an embodiment of the invention depicted in the Figures will be described in further detail with reference thereto. In the drawing show:

[0022] FIG. 1 a perspective partial view of an exhaust gas cooler according to the invention, and

[0023] FIG. 2 a sectional view of the inlet region of the exhaust gas cooler according to the invention.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION

[0024] As can be seen in FIG. 1 the exhaust gas cooler 10 according to the invention is mountable in the depicted case via a flange provided at its inlet 12 and comprises in the direction of flow (in FIG. 1 downward) numerous exhaust gas channels or tubes 16, which, for better heat transfer, can be filled with ribs or fins. The exhaust gas tubes 16 conventionally have a constant cross section in the direction of flow and are defined by walls which, a few millimeters or centimeters from the inlet, in the case of initially adjacent walls, comprise stages 18 extending away from one another such that flow channels 20 for coolants are defined. The edges, located in FIG. 1 above, of the walls of the exhaust gas tubes 16 consequently point in the direction of flow and, due to the inflowing hot exhaust gas, become especially hot. To protect the described edges of the walls, caps 22 are provided according to the invention, of which in FIG. 1 only one cap is depicted. However, it is understood that further edges can preferably comprise such caps 22 or coverings. In FIG. 1 a securement tab 24 extending in the direction of flow from the cap 22 is evident of which on each on each side, in FIG. 1 left and right, two or more can be provided. In FIG. 1 is further evident that the cap 22 is implemented symmetrically with respect to a plane containing the direction of flow and the edge at the inlet.

[0025] This is supplementarily evident in FIG. 2. Here, again, the symmetry with respect to a plane can be seen which comprises in the direction of flow (in FIG. 2 from right to left) and the extent of the edge of the exhaust gas tube (in FIG. 2 perpendicular to the plane of the drawing). Further evident in FIG. 2 is the rounded front end, pointing in the direction of flow of the covering 22. Over approximately half of the course of the covering in the direction of flow, it is implemented with a minimal obliquity, meaning it is implemented at an acute angle with respect to the direction of flow. Adjacent thereto is a section largely parallel to the direction of flow. Succeeding thereto is implemented a stage 18 and by means of a further section implemented approximately parallel to the direction of flow, is carried out the attachment on those walls of two adjacent exhaust gas tubes that define between them flow channels 20 for liquid coolant. In the interior of cap 22 and toward the wall of the particular exhaust gas tube, an air gap is formed which ensures the described thermal insulation. With the possible exception of securement tabs, the cap, over its extent along the edge of the exhaust gas tube, which means in FIG. 2 perpendicularly to the plane of drawing, advantageously has a constant profile.