FR2855605A1 - Heat exchanger e.g. super charge air cooler, for cooling exhaust gas of motor vehicle engine, has inlet and outlet collection boxes provided for exhaust gas flow on both sides of heat exchange beam - Google Patents

Abstract

The exchanger has an envelope (4) with a heat exchange beam (2). An inlet collection box (8) and an outlet collection box (6) are provided for an exhaust gas flow on both sides of the beam. The envelope has two opposite ends (17, 18) extending on both sides of the beam, where the envelope ends are received by a groove. The inlet and outlet collection boxes are assembled by bonding at the ends of the envelope.

Description

Heat exchanger, in particular air cooler

  The invention relates to the field of brazed heat exchangers for motor vehicles, such as, for example, charge air coolers.

  More specifically, it relates to a heat exchanger for the heat exchange between a liquid fluid and a gaseous fluid comprising a heat exchange bundle, an envelope housing this heat exchange bundle, an inlet manifold and an outlet manifold for the gaseous fluid, arranged on either side of the bundle.

  In order to improve their performance, the engines of modern vehicles are frequently supplied with compressed air (charge air) by a compressor driven by the exhaust gases. However, this compression has the effect of heating the air in such a way that it is necessary to cool it in order to lower its temperature before it is introduced into the engine cylinders. For this purpose, the vehicle is equipped with a charge air cooler. Exchangers of this type generally include manifold boxes for the intake and evacuation of the charge air. These boxes are molded from aluminum or plastic. They are assembled with a heat exchange bundle 30 consisting of plates between which are arranged corrugated intermediate elements.

  However, the stacking of the plates results in a dispersion of the height of the heat exchange beam. This dispersion is inherent in the manufacturing process.

  This variation in dimension does not allow, as in the case of a bundle made up of tubes, to mount a manifold capable of receiving the seal and the manifold.

  In order to overcome this difficulty, it is known to house the heat exchange bundle in a plastic or molded aluminum box comprising the air inlets and outlets and to close this box by a welded or crimped cover (DE 1 999 025 04 and JP 1 023 89 69).

  The mounting of the beam in a box overcomes this difficulty. However, this housing must be reinforced to resist pressure and avoid any deformation of the walls, which could create leakage passages. This problem is all the more crucial as the volume subjected to the pressure is large, which leads to a penalizing bulk, in particular if the case is made of plastic.

  The object of the present invention is in particular to produce a heat exchanger which overcomes these drawbacks.

  This object is achieved by the fact that the envelope has two opposite ends which project on either side of the bundle, the inlet manifold box and the outlet manifold box being assembled at these two protruding ends. This assembly is preferably carried out by gluing.

  Advantageously, the inlet manifold and the outlet manifold each have a groove which receives the projecting ends of the envelope.

  Thanks to these characteristics, the bundle consists of a minimum of parts. It is not necessary to provide a manifold and a seal between the manifold and the manifold.

  In a preferred embodiment, the envelope consists of two half-shells able to slide relative to one another to adjust to variations in height of the beam during brazing.

  + '2855605 In a particular embodiment, each half-shell has a U-shaped section comprising a bottom wall and two side edges located on either side of the bottom wall, the side edges of one of the half -shells 5 sliding relative to the lateral edges of the other half-shell.

  Advantageously, the grooves of the inlet and outlet manifolds comprise parts which receive the bottom walls and parts which receive the lateral edges of the two half-shells, the parts of the grooves which receive the bottom walls having a width. greater than the thickness of these walls so as to accommodate a variation in height of the heat exchange bundle. Thanks to these characteristics, the assembly is not dependent on variations in dimensions of the height of the beam after brazing. In fact, the fact that the two half-shells slide relative to one another makes it possible to adjust them to the height of the beam. Then, the width of the parts of these grooves which receive the bottom walls of each of the two half-shells makes it possible to adapt to variations in the spacing of these two walls.

  In a particular embodiment, the inlet and outlet manifolds have a heel in which the grooves for receiving the projecting ends of the envelope are formed.

  Advantageously, the parts of the grooves of the manifolds which receive the lateral edges of the two half-shells have a zone of greater width to accommodate the sliding of the lateral edges of one half-shell relative to the lateral edges of the other half-shell. In a particular embodiment, the U-shaped section of one of the half-shells is inserted inside the U-shaped section of the other half-shell.

  The concavities of the two U-shaped half-shells can be in the same direction or on the contrary in the opposite direction.

  Finally, according to yet another embodiment, each half-shell has a lateral edge located inside the U of the other half-shell.

  One can provide that one of the half-shells has a main face which extends over a distance greater than the distance over which the main face of the other of the half-shells extends.

  Other characteristics and advantages of the invention will become apparent on reading the following description of embodiments given by way of illustration with reference to the appended figures. In these figures: - Figure 1 is an exploded perspective view and Figure 2 an assembled view of a charge air cooler according to the invention; - Figure 3 is a detailed sectional view showing a groove for receiving the edges projecting from the envelope; - Figure 4 is a schematic view showing the embodiment of the two half-shells of the exchanger shown in Figures 1 and 2; - Figures 5 and 6 are two alternative embodiments of the two half-shells; - Figure 7 is a partial view on an enlarged scale showing an area of greater width of the groove for receiving the projecting ends of the envelope; and FIG. 8 is a perspective view of a heat exchanger according to an alternative embodiment of that of FIGS. 1 and 2.

  FIGS. 1 and 2 show a heat exchanger according to the invention, produced here in the form of a charge air cooler intended for a motor vehicle. It consists of a bundle designated by the general reference 2 housed inside an envelope designated by the general reference 4, an upper manifold box 6 and a lower manifold box 8 for the air of overeating.

  The bundle 2 consists, in a conventional manner, of stamped plates 7 of elongated rectangular shape which alternate with secondary exchange surfaces and / or disturbing elements, produced here in the form of corrugated spacers 9 (FIG. 1). The plates 7 and the spacers 9 15 are advantageously made of an aluminum alloy and brazed together. The plates 7 are assembled in pairs and delimit between them alternating circulation channels for a coolant, most often the cooling water of the engine circuit, and for the charge air to be cooled.

  In the example, each plate has two bosses located along one of its short sides which define an inlet manifold and an outlet manifold for the cooling water. Since this embodiment is known, it will not be described in detail. The envelope 4 which houses the bundle 2 consists of two half-shells 10 and 12, advantageously also made of an aluminum alloy. The assembly formed by the plates 7, the corrugated interleaves 9 and the two half-shells 10 and 12 can thus be brazed to constitute the bundle 2.

  As can be seen more particularly in FIG. 4, these half shells 10 and 12 have a very elongated general U-shaped section. Each half-shell has a bottom wall 13 and two lateral edges 14 and 15. The lateral edges 14 are shorter than the lateral edges 15.

  In addition, the latter comprise a recess 16 by a distance corresponding to the thickness of the sheet in which the half-shells are made in order to allow the adaptation of the two half-shells one on the other. Thus, the two half-shells 10 and 12 can slide relative to each other and the spacing (height H) between the two bottom walls 13 can vary. Thanks to this characteristic, the casing 4 can adapt to the height dispersions of the stack of plates and corrugated spacers of the heat exchange bundle 2 so that the bottom walls 13 are in contact with each of the two 10 ends of this bundle.

  Furthermore, as can be seen more particularly in FIG. 1, the width of each of the two half-shells 10 and 12 is greater than the width of the plates which constitute the heat exchange bundle 2. In this way, the the envelope 4 has an upper projecting end 17 and a lower projecting end 18.

  An inlet pipe 20 and an outlet pipe 22 for the cooling water are also provided on the half-shell 12. The inlet pipe 20 is opposite the inlet manifold of the heat exchange bundle and the tube 22 is opposite the outlet manifold. Thus, the cooling water enters via the tube 20, as shown diagrammatically by the arrow 23, it traverses the heat exchange beam in the direction of its length, a first time from left to right, according to FIG. 1 then makes a U-turn and returns to the outlet pipe 22 before leaving the exchanger as shown in diagram by the arrow 24. Of course, the cooling water can make more than two back-and-forth movements in the heat exchange bundle.

  The upper manifold 6 is adapted to the upper protruding end 17 and the lower manifold 8 is adapted to the protruding end 18. For this purpose, each of the manifolds 6 and 8 has a heel 26 in which is provided a groove 28 which extends over the entire periphery of the manifolds (Figures 1 and 3). A quantity of glue 30 is placed inside the groove 28 for fixing the projecting ends 17 and 18 of the two half-shells (FIG. 3). In order to accommodate the variations in height of the heat exchange bundle 2 and, consequently, the variations in spacing of the two bottom walls 13 of the two half-shells 10 and 12, the two rectilinear parts of the groove 28 which receive the two bottom walls 13 have a width L greater than the thickness E of the sheet in which the half-shells 10 and 12 are formed. Thus, the bottom walls 13 can be inserted into the grooves with a clearance which allows them to adapt to variations in height of the heat exchange bundle.

  The parts of the grooves which receive the lateral edges 14 and 15 of the half-shells 10 and 12 have a width greater than the thickness of the sheets in which the half-shells are made. However (FIGS. 1 and 7) the parts of the groove 28 which receive the side edges have a part of greater width 32 intended to receive the superimposed ends of the side walls 14 and 15. In other words, the thickness of the groove in the area 32 is twice its current thickness. The length of the portion of greatest thickness is sufficient to take account of variations in height of the heat exchange bundle.

  In the charge air cooler which has just been described, the air to be cooled enters via an inlet pipe 34 of the lower manifold 8, as shown diagrammatically by the arrow 35, then it passes through the beam of heat exchange from bottom to top, according to FIG. 1, before exiting through an outlet pipe 36 from the upper manifold 6, as shown by arrow 37.

  The manifolds 6 and 8 can be made of molded plastic or molded aluminum, or of another material. The glue 30 used for assembling the manifolds and the bundle envelope will be chosen according to the nature of the materials to be assembled.

  Advantageously, a silicone type adhesive is used, given its flexibility and its ability to absorb differences in expansion.

  FIGS. 5 and 6 show two alternative embodiments of the half-shells 10 and 12. In FIG. 5, the envelope consists of two half-shells 38 and 40 each having the shape of a very elongated U, the half-shell 38 being slightly shorter than the half-shell 10 40 so as to be able to be inserted inside the branches 15 of the U of the latter and slide therein so, as explained above, to be able to adjust to the distance between the two bottom walls 13 of the half-shells 38 and 40.

  Sure. Figure 6, the envelope consists of two half-shells 42 and 44 both having a U-shaped section. The half-shell 44 has two side edges 15 of length slightly greater than that of the side edges 14 of the upper shell 42. However, the side edges 14 are slightly more spaced than the side edges 15 in order to allow the latter to be introduced into the U-shaped profile of the upper half-shell 42.

  In Figure 6, the concavities of the U are opposite, while in Figure 5, they were of the same direction. The shells 42 and 44 can thus slide freely with respect to each other in order to adjust, as has been explained, to a variation in the height of the heat exchange bundle 2. Of course, the embodiments of the Figures 4 to 6 are given by way of example only, and the shells could be made in other ways, within the reach of ordinary skill in the art, without departing from the scope of the present invention. Figure 8 illustrates an alternative embodiment of the heat exchanger of Figures 1 and 2. The heels 26 of the manifolds 6 and 8 define non-coplanar assembly areas. The respective parts of the heels 26 which extend from the side of the half-shell 10 are spaced apart by a distance D1, while the respective parts of the heels 26 which extend from the side of the half-shell 12 are spaced apart by a distance D2 which is greater than the distance D1. The half-shell 12 thus has a larger main face than the corresponding main face of the half-shell 10, which makes it possible to provide a larger surface that can be used, for example, for fixing another heat exchanger.

  The invention is not limited to charge air coolers for motor vehicles and can be applied to other types of heat exchangers.

Claims (14)

claims   1. Heat exchanger for the heat exchange between a liquid fluid and a gaseous fluid, comprising a heat exchange bundle 5 (2), an envelope (4) housing this bundle (2), a manifold inlet (8) and an outlet manifold (6) for the gaseous fluid, arranged on either side of the bundle (2), characterized in that the casing (4) has two opposite ends (17, 18) 10 which project from either side of the bundle (2), the inlet manifold box (8) and the outlet manifold box (6) being assembled at these two projecting ends (17, 18).   2. Heat exchanger according to claim 1, characterized in that the inlet manifold box (8) and the outlet manifold box (6) are assembled by gluing.   3. Heat exchanger according to one of claims 1 and 20 2, characterized in that the inlet manifold box and the outlet manifold box (8, 6) each have a groove (28) which receives the projecting ends ( 17, 18) of the envelope (4).   4. Heat exchanger according to one of claims 1 to 3, characterized in that the casing (4) consists of two half-shells (10, 12; 38, 40; 42, 44) capable of sliding the one relative to the other to adjust to variations in height of the beam (2) during soldering. 30 5. Heat exchanger according to claim 4, characterized in that each half-shell has a U-shaped section comprising a bottom wall (13) and two lateral edges (14, 15) located on either side of the bottom wall (13), the side edges of one of the half-shells sliding relative to the side edges of the other half-shell.   6. Heat exchanger according to claim 5, characterized in that the grooves (28) of the inlet and outlet manifolds (6, 8) have parts which receive the bottom walls (13) and parts which receive wind the lateral edges (14, 15) of the two half-shells (10, 12), the parts of the grooves which receive the bottom walls (13) having a width (L) greater than the thickness (E) of these walls to accommodate a variation in the height of the heat exchange bundle (2). 10 7. Heat exchanger according to one of claims 1 to 6, characterized in that the inlet and outlet manifolds (6, 8) have a heel (26) in which the receiving grooves (28) of the ends protruding from the envelope (4) are formed.   8. Heat exchanger according to one of claims 5 to 7, characterized in that the parts of the grooves (28) of the manifolds which receive the lateral edges of the two half-shells (10, 12) have one more area large width (32) to accommodate the sliding of the side edges (14, 15) of a half-shell relative to the side edges (14, 15) of the other half-shell (10, 12).   9. Heat exchanger according to one of claims 5 to 8, characterized in that the U-shaped section of one of the half-shells is inserted inside the U-shaped section of the another half-shell (38, 40; 42, 44).   10. Heat exchanger according to claim 9, characterized in that the concavities of the half-shells (38, 40) are in the same direction.   11. Heat exchanger according to claim 9, caracté35 risé in that the concavities of the half-shells (42, 44) are in opposite directions (42, 44).   12. Heat exchanger according to claim 9, characterized in that each half-shell (10, 12) has a lateral edge (14, 15) located inside the U on the other side of the half-shell.   13. Heat exchanger according to one of claims 1 to 5 12, characterized in that the inlet and outlet manifolds (8, 6) are molded from plastic or aluminum.   14. Heat exchanger according to one of claims 1 to 13, characterized in that one (12) of the half-shells has a main face which extends over a distance (D2) greater than the distance (D1) on which the main face of the other (10) half-shells extends.