Exhaust gas recirculation cooler

Abstract

An exhaust gas recirculation cooler may include a heat exchanger block including a first mounting flange, a diffuser including a second mounting flange, and at least one non-return valve arranged between the heat exchanger block and the diffuser. The exhaust gas recirculation cooler may also include a valve carrier which supports the at least one non-return valve and on which a gasket is arranged. The heat exchanger block may be connected via the first mounting flange directly to the second mounting flange of the diffuser. The valve carrier may be arranged between the heat exchanger block and the diffuser, and with the gasket may seal a sealing point between the first mounting flange and the second mounting flange. The diffuser may include an outwardly closed recess with a peripheral rim structured to accommodate the valve carrier. The rim may define the second mounting flange.

Claims

1. An exhaust gas recirculation cooler, comprising: a heat exchanger block including a first mounting flange; a diffuser including a second mounting flange; at least one non-return valve arranged between the heat exchanger block and the diffuser; and a valve carrier which supports the at least one non-return valve and on which a gasket is arranged; the heat exchanger block connected via the first mounting flange directly to the second mounting flange of the diffuser; wherein the valve carrier is arranged between the heat exchanger block and the diffuser, and with the gasket seals a sealing point between the first mounting flange and the second mounting flange; wherein the diffuser includes (i) a recess in which the valve carrier is disposed and retained, and (ii) a peripheral rim extending around and defining an outer radial boundary of the recess; and wherein the rim defines the second mounting flange.

2. The exhaust gas recirculation cooler according to claim 1, wherein the valve carrier and the gasket are structured as a 2-part plastic component.

3. The exhaust gas recirculation cooler according to claim 1, wherein the valve carrier is composed of at least one of steel and aluminium.

4. The exhaust gas recirculation cooler according to claim 1, wherein the gasket is secured via moulding onto the valve carrier.

5. The exhaust gas recirculation cooler according to claim 1, further comprising at least two separate exhaust gas channels, wherein the at least one non-return valve includes two non-return valves supported by the valve carrier each associated with a respective one of the at least two exhaust gas channels.

6. The exhaust gas recirculation cooler according to claim 1, wherein the diffuser is structured such that an exhaust gas flow flowable therethrough is redirected at about 90.

7. The exhaust gas recirculation cooler according to claim 1, wherein the valve carrier includes at least one seating structured to accommodate the at least one non-return valve, and wherein another gasket is arranged on at least one of the at least one seating and the at least one non-return valve.

8. An internal combustion engine comprising at least one exhaust gas recirculation cooler including: a heat exchanger block including a first mounting flange; a diffuser including a recess and a peripheral rim defining a second mounting flange, the heat exchanger block connected via the first mounting flange directly to the second mounting flange; at least one non-return valve arranged between the heat exchanger block and the diffuser; and a valve carrier supporting the at least one non-return valve and on which a gasket is arranged, the valve carrier arranged between the heat exchanger block and the diffuser such that the gasket abuts against the first mounting flange and the second mounting flange sealing a sealing point therebetween; wherein the valve carrier is disposed and retained within the recess; and wherein the rim extends around and defines an outer radial boundary of the recess.

9. The internal combustion engine according to claim 8, wherein the valve carrier and the gasket are structured as a 2-part plastic component.

10. The internal combustion engine according to claim 8, wherein the gasket is arranged on and connected to the valve carrier via a moulded-on connection.

11. The internal combustion engine according to claim 8, further comprising at least two separate exhaust gas channels, wherein the at least one non-return valve includes two non-return valves supported by the valve carrier each associated with a respective one of the at least two exhaust gas channels.

12. The internal combustion engine according to claim 8, wherein the diffuser is structured such that an exhaust gas flow flowable therethrough is redirected at about 90.

13. The internal combustion engine according to claim 8, wherein the valve carrier includes at least one seating structured to accommodate the at least one non-return valve, and wherein another gasket is arranged on at least one of the at least one seating and the at least one non-return valve.

14. An exhaust gas recirculation cooler, comprising: a heat exchanger block including a first mounting flange; a diffuser including a recess and a peripheral rim defining a second mounting flange, the heat exchanger block connected via the first mounting flange directly to the second mounting flange such that only a single sealing point is present between the heat exchanger block and the diffuser; at least two separate exhaust gas channels; at least two non-return valves each associated with a respective one of the at least two exhaust gas channels arranged between the heat exchanger block and the diffuser; and a valve carrier supporting the at least two non-return valves and on which a gasket is arranged, the valve carrier arranged between the heat exchanger block and the diffuser such that the valve carrier and the gasket seal the single sealing point between the first mounting flange and the second mounting flange; wherein the valve carrier is disposed and retained within the recess; and wherein the rim extends around and defines an outer radial boundary of the recess.

15. The exhaust gas recirculation cooler according to claim 14, wherein the valve carrier includes at least two seatings each structured to accommodate an associated one of the at least two non-return valves.

16. The exhaust gas recirculation cooler according to claim 15, further comprising another gasket arranged on at least one of (i) at least one of the at least two seatings and (ii) at least one of the at least two non-return valves.

17. The exhaust gas recirculation cooler according to claim 1, wherein the gasket abuts against the first mounting flange and the second mounting flange sealing a sealing point therebetween.

18. The exhaust gas recirculation cooler according to claim 1, wherein the heat exchanger block and the diffuser are directly connected to one another via the first mounting flange and the second mounting flange such that only a single sealing point is present between the heat exchanger block and the diffuser.

19. The exhaust gas recirculation cooler according to claim 1, wherein: the recess is an annular recess defined by and between the first mounting flange and the second mounting flange; and at least a portion of the at least one non-return valve is disposed and retained within the annular recess.

20. The exhaust gas recirculation cooler according to claim 19, wherein the gasket is arranged within the recess and abuts against the first mounting flange and the second mounting flange sealing a sealing point therebetween.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the drawings,

(2) FIG. 1 is a schematic representation of a cross section through an exhaust gas recirculation cooler according to the invention,

(3) FIG. 2 is a schematic representation of the device of FIG. 1 but in exploded view.

DETAILED DESCRIPTION

(4) According to FIGS. 1 and 2, an exhaust gas recirculation cooler 1 according to the invention has a heat exchanger block 2 with a first mounting flange 3, and a diffuser 4 with a second mounting flange 5. At least one, in this case in fact two, non-return valves 6 are arranged between the heat exchanger block 2 and the diffuser 4. These are intended to prevent undesirable reflux of exhaust gas 14. The first mounting flange 3 may be constructed integrally with a housing 7 of the heat exchanger block 2 or also attached thereto. According to the invention, a valve carrier 8 (see FIG. 2 in particular) is provided, which supports the at least one non-return valve 6, in this case the two non-return valves 6, and on which at the same time a gasket 9 is arranged, particularly moulded. The heat exchanger block 2 is connected directly via its first mounting flange 3 to the second mounting flange 5 of the diffuser 4, wherein the valve carrier 8 is arranged between the heat exchanger block 2 and the diffuser 4 and seals a sealing 10, which may also be described as an outer sealing point 10 between the first mounting flange 3 and the second mounting flange 5 with the gasket 9.

(5) In the exhaust gas recirculation cooler known from the related art, an intermediate flange was also arranged between the diffuser 4 and the heat exchanger block 2, on which the non-return valves 6 were supported. However, this embodiment necessitates the user of two outer sealing point 10, one between the intermediate flange and the first mounting flange 3 of the heat exchanger block 2 and the other between the intermediate flange and the second mounting flange 5 of the diffuser 4. Now with the exhaust gas recirculation cooler 1 according to the invention, this may be reduced to only a single outer sealing point 10. This is also made possible by the fact the diffuser 4 has an outwardly closed recess 11 having a peripheral rim 12 to accommodate the valve carrier 8, wherein said rim 12 at the same time forms the second mounting flange 5 with a direct contact surface with the first mounting flange 3. Purely theoretically of course, it is also conceivable that at least part of the recess 11 to accommodate the valve carrier 8 may also be provided in the first mounting flange 3 of the heat exchanger block 2. All in all, however, the exhaust gas recirculation cooler according to the invention enables the number of outer sealing points 10 to be reduced from two as was the case previously to just one single point now according to the invention, so that the seal between the heat exchanger block 2 and the diffuser 4 may be designed not only less expensively but also more functionally reliably. In particular, with the exhaust gas recirculation cooler 1 according to the invention, the previously essential intermediate flange may also be dispensed with, resulting in an reduction of the number of parts quired and consequently also of the associated assembly, storage and logistical costs.

(6) The valve carrier 8 may be constructed for example from plastic, in particular a s plastic injection moulded part, enabling it to be produced not only inexpensively but also to a high quality standard. In this context, of course the valve carrier 8 and the gasket 9 may also be constructed as bi-component injection moulded plastic components or a two-component plastic part, which in turn makes it possible to use different plastics for the valve carrier 8 on the one hand and the gasket 9 on the other. For the gasket 9, EPDM is a possible material, for example.

(7) Production of the valve carrier 8 and the gasket 9 as a two-component plastic part in particular make it possible to dispense with labour-intensive, expensive post-processing. It is also conceivable that the valve carrier 8 and the gasket 9 may easily be installed in the exhaust gas recirculation cooler together.

(8) Purely theoretically, of course it is also conceivable for the gasket 9 to be moulded onto a separately produced valve carrier 8 made of plastic, steel or aluminium, and is connected thereto in this way. The moulded construction and/or construction of the valve carrier 8 with the gasket 9 as a bi-component injection moulded plastic part may serve to obtain a particularly leak-proof and reliable attachment between the gasket 9 and the valve carrier 8.

(9) Upon further review of FIGS. 1 and 2, it may be seen that the exhaust gas recirculation cooler 1 according to the invention has two separate exhaust gas channels 13, 13 and two associated non-return valves 6, which are supported by the valve carrier 8 and in particular are inserted in seatings 17 therein. In this case, a gasket 9 may be arranged on the seating 17 and/or on the non-return valve 6, thereby sealing an inner sealing point 10.

(10) At the same time, the diffuser 4 shown in FIGS. 1 and 2 is constructed in such manner that it causes a redirection of an exhaust gas stream 14 through about 90. The diffuser 4 itself may be made for example from metal or plastic, wherein the non-return valves 6 and thus also the valve carrier 8 may be arranged downstream and/or upstream from the heat exchanger block 2 in the direction of the flow.

(11) The exhaust gas recirculation cooler 1 according to the invention may be installed in a motor vehicle 15, particularly in an internal combustion engine 16.

(12) With the exhaust gas recirculation cooler 1 according to the invention, it is possible to reduce the number of outer sealing point 10 by half, regardless of the number of exhaust gas channels 13, 13, and also regardless of the number of non-return valves 6, so that for any embodiment only a single sealing point 10 has to be sealed off from the outside. This in turn enables production and manufacturing costs to be reduced, particularly in terms of the flatness and tolerances on the sealing surfaces of the mounting flanges 3, 5.