FR2868522A1 - Heat exchange module for motor vehicle, has secondary heat exchanger having collecting case soldered with tube bundle, while main heat exchanger has collection plate soldered with another tube bundle and cover - Google Patents

Abstract

The module has main and secondary heat exchangers (10, 14) with respective tube bundles (16, 30). The tube bundles are soldered with fins (36). The secondary heat exchanger has a collecting case (32) soldered with the bundle (30), while the main heat exchanger has a collection plate (20) soldered with the bundle (16) and a cover (38) that is mounted on the collection plate by lateral deformable parts (26). An independent claim is also included for a method of fabricating a heat exchange module.

Description

VTM1521.FRD

  The invention relates to the field of heat exchangers, in particular for motor vehicles.

  It relates more particularly to a heat exchange module comprising a main heat exchanger and at least one secondary heat exchanger, each heat exchanger comprising a bundle of tubes connected to at least one header, and wherein the bundles of tubes respective heat exchangers are brazed to fins.

  Such a heat exchange module thus constitutes a monoblock unit which includes a main heat exchanger and one or more secondary heat exchangers.

  Most often, such a heat exchange module consists of a cooling radiator of the engine of a vehicle and a condenser forming part of the air conditioning circuit of the passenger compartment of the vehicle.

  In such a module, the respective tube bundles of the heat exchangers are joined together by common elements which are most often constituted either by common fins, or by common side parts, also called "cheeks".

  In the first case, the common fins provide a mechanical connection between the respective beams of the heat exchangers. At the same time, they constitute heat exchange surfaces common to the respective beams of the heat exchangers.

  In the second case, the heat exchangers have separate fins which are connected at both ends of the module to the aforementioned lateral parts to ensure the cohesion of the assembly.

  In the particular application mentioned above, the various bundles of tubes of the heat exchange module are traversed by a same air flow which, on the one hand, cools the cooling fluid flowing through the cooling radiator and, d on the other hand, the refrigerant flowing through the condenser.

  Heat exchange modules of this type which can be made either by a mechanical assembly or by a brazed connection are already known.

  In the case of a heat exchange module of the mechanical type, the fins are usually made in the form of planar fins provided with openings which are traversed by the respective tubes of the exchangers.

  In an exemplary embodiment, as described in WO 03/042619, the fins comprise openings which are traversed by the tubes of a heat exchanger and openings which open on an edge of the fins to allow the lateral introduction of the tubes of one or more other heat exchangers. In this case, the fins are common to the heat exchangers.

  In the case of a brazed structure heat exchange module, the fins are usually made in the form of corrugated fins, also called corrugated spacers, the respective corrugations of which are brazed to the tubes of the various heat exchangers.

  In this case, the tubes of the heat exchangers are of flat type and the respective flat faces of the tubes are each time brazed to the corrugations of the fins, whether they are common fins or separate fins.

  The interest of brazed type modules is to allow their manufacture by a single brazing operation, by passing through a suitable oven. It is known for that to realize all the elements of the module in a metal material, usually aluminum or aluminum alloy.

  As a result, therefore, the respective manifolds of the heat exchangers are also made of a metallic material and soldered together with the other elements of the module.

  This known solution, however, has disadvantages.

  First of all, the cost of producing the collector boxes 15 of metallic material is high. Then, the technical realization of such boxes is difficult.

  In addition, the flexibility of use of such boxes is reduced, in that it is difficult to provide accessories, for example fixing brackets, on such metal cans, except to make their cost prohibitive.

  Finally, the rigidity of such metal cans complicates the problem of thermal shock resistance.

  The object of the invention is in particular to overcome the aforementioned drawbacks.

  In particular, it aims to propose a heat exchange module, of the type defined in the introduction, the technical realization of which is simplified and can be obtained at a lower cost.

  The invention also aims to provide such a heat exchange module which offers great flexibility as to the manifold used in the module.

  It is also intended to provide such a heat exchange module that provides increased resistance to thermal shock.

  To this end, the invention proposes a heat exchange module of the type defined in the introduction, in which the header box of the secondary heat exchanger is soldered to the tubes of this secondary heat exchanger, whereas the collecting box of the main exchanger comprises a collector plate brazed to the tubes of this main heat exchanger and a cover provided with a peripheral rim and crimped on the collector plate by crimping means issuing from the collector plate and bearing against the peripheral rim of the lid.

  Thus, the invention proposes a heat exchange module which, for the most part, is obtained by soldering of its various components, including the collector box (s) of the secondary heat exchanger (s).

  The particularity of the invention lies in the fact that the (or each) header box of the secondary heat exchanger is obtained by crimping a lid on a header plate which is itself brazed to the tubes of the exchanger of main heat.

  Under these conditions, all components of the module are sold by soldering in a single operation except for the header of the main heat exchanger header box which is then crimped together.

  The lid can be easily obtained by molding a suitable material which may be a plastic or metal material.

  This solution has many advantages.

  First of all, the cost of the header of the main heat exchanger is reduced, since it comprises a cover that can be easily obtained by molding with appropriate shapes that can include accessories made integral with the cover.

  Crimping is a known operation and widely used in production. The flexibility of the molded manifold, for example plastic, is retained. The possibility of installing accessories is preserved.

  Finally, the thermal shocks return to their usual level.

  However, the crimping of the cover on a collector plate provided with crimping means poses certain problems of realization, in the case of the module of the invention, because of the proximity of the collector box of the secondary heat exchanger.

  Thus, in the particular case of a heat exchange module, consisting of an engine cooling radiator and an air conditioning condenser, the collector boxes of the condenser are most often made in a tubular form. In such a module, this tubular manifold is in close proximity to the header plate of the main heat exchanger, which poses problems for the implementation of crimping. The invention, however, provides different solutions to enable crimping.

  In a first solution, which constitutes a preferred solution, the crimping means comprise a raised edge coming from the collecting plate and having lateral deformation parts able to bear against the peripheral rim of the cover.

  In other words, the crimping is carried out in a lateral manner as taught, for example, by US Pat. No. 4,331,201. The crimping force then takes place in a direction generally parallel to the plane of the collector plate.

  In another solution, the crimping means comprise a crenellated edge from the header plate and having foldable legs adapted to bear against the peripheral rim of the cover.

  In this case, the crimping force is in a direction generally perpendicular to the general plane of the collector plate, and not in a direction generally parallel to this plane, as in the case of the solution mentioned above.

  In one embodiment of the invention, the module comprises a main heat exchanger and a single secondary heat exchanger.

  For example, the main heat exchanger is a cooling radiator of a vehicle engine, while the secondary heat exchanger is a condenser forming part of an air conditioning system of the vehicle.

  Advantageously, the tubes of the main heat exchanger and the tubes of the secondary heat exchanger are flat tubes.

  In this case, the fins of the main heat exchanger and / or the secondary heat exchanger are corrugated interlayers whose corrugations are brazed to the flat tubes.

  In one embodiment of the invention, the main heat exchanger and the secondary heat exchanger (s) have common fins.

  In another embodiment of the invention, the main heat exchanger and the secondary heat exchanger (s) have separate fins.

  According to another characteristic of the invention, the main heat exchanger and the secondary heat exchanger (s) have common lateral parts, also called "cheeks".

  In the particular application mentioned above, the header of the secondary heat exchanger is tubular.

  In another aspect, the invention relates to a method of manufacturing a heat exchange module as defined above, which comprises the following operations: a) preparing a main heat exchanger comprising a bundle of tubes connected to a less a collector plate provided with crimping means; b) preparing at least one secondary heat exchanger comprising a bundle of tubes connected to at least one header; c) preparing fins and possibly side pieces; d) brazing together the main heat exchanger resulting from step a), the secondary heat exchanger resulting from step b) and the fins resulting from step c); e) preparing a lid provided with a peripheral rim; and f) crimping the cover on the header plate of the main heat exchanger via the crimping means which abut the peripheral rim of the cover, by interposing a seal.

  In one embodiment of the invention, the crimping operation f) comprises the lateral deformation of lateral deformation portions that comprise a raised edge from the header plate.

  In another embodiment, the crimping operation f) comprises deforming foldable tabs that comprise a crenellated edge from the header plate.

  In yet another embodiment, the crimping operation f) comprises engaging a first longitudinal side of the peripheral rim of the lid under folded tabs from a first longitudinal side of the collector plate, pivoting the lid of so as to bring a second longitudinal side of the cover of a second longitudinal side of the header plate, which is provided with foldable tabs and fold the collapsible tabs against the second longitudinal side of the peripheral rim of the cover.

  Whatever the chosen solution, it is advantageous that the crimping operation f) comprises the establishment of a support member under the header plate to withstand crimping efforts.

  In one embodiment, this support member includes teeth arranged to engage between the tubes of the main heat exchanger and under the header plate.

  In the description which follows, given by way of example only, reference is made to the accompanying drawings, in which: FIG. 1 is a partial cross-sectional view of a two-part heat exchange module; exchangers, according to a first embodiment of the invention; FIG. 2 is a view similar to FIG. 1 illustrating a heat exchange module according to a second embodiment of the invention; - Figure 3 is a view similar to Figure 2 showing the use of a support member for crimping; - Figure 4 is a sectional view along the line IV-IV of Figure 3; FIG. 5 is a partial sectional view of a heat exchange module in a third embodiment of the invention; FIG. 6 is a partial sectional view of a heat exchange module in a fourth embodiment of the invention illustrating crimping by a wheel; and FIG. 7 is a partial perspective view of a heat exchange module in a fifth embodiment of the invention, in which the two heat exchangers are connected by side pieces of the cheek type.

  Referring first to Figure 1 which shows a part of a heat exchange module, generally designated by the reference 10, and comprising a main heat exchanger 12 and a single secondary heat exchanger 14. In the example, the main heat exchanger 12 is a cooling radiator of a motor vehicle engine, while the secondary heat exchanger 14 is a condenser forming part of an air conditioning circuit of the vehicle.

  The heat exchanger 12 comprises a bundle of tubes 16, in the example of the flat tubes, one end of which opens into holes 18, of conjugate shape, which comprises a collecting plate 20. In the example, this plate collects trice comprises a bottom 22, in which are formed the holes 18 and a raised edge 24 having laterally deformable portions 26 and constituting crimping means. As can be seen, the bottom 22 defines, at the periphery, a groove 28.

  The secondary heat exchanger 14 comprises a bundle of tubes 30, also flat tubes, one end of which opens into a manifold 32 of tubular shape, which has openings 34 into which the tubes 30 of the bundle open.

  The main exchanger 10 may, at its opposite end, comprise a collector plate similar to the collector plate 20. Similarly, the secondary heat exchanger 14 may, at its other end, comprise another collector box similar to the collector box 32.

  The various components described above are made of a metallic material, for example aluminum or aluminum-based alloy, and are brazed together, in a single operation with common fins 36 which, in the example, are of corrugated type. These common fins are also made of the same metallic material or the like. These corrugated fins 36, also called corrugated spacers, comprise corrugations or folds which are brazed each time on a flat face of a tube 16 and a flat face of a tube 30, which makes it possible to produce a one-piece assembly at a distance of after the soldering operation.

  According to the invention, the main heat exchanger 12 comprises a collecting box resulting from the assembly of a cover 38, advantageously made of plastic, and of the collecting plate 20. The cover 38 has a bottom 40 with a cross section. dome shape provided with a peripheral rim 42 of generally rectangular shape. This peripheral flange 42 is received in the groove 28 with the interposition of a seal 44. The crimping is performed here laterally, that is to say by a force exerted on the deformable parts 26 in a generally parallel direction at the bottom 22 of the collector plate, that is to say perpendicular to the axes of the tubes 16.

  The crimping takes place in the direction of arrows F1 as shown in Figure 1. Such crimping is known and described in particular in US 4,331,201, already cited. To allow such crimping, the raised edge 24 has a number of cutouts (not shown) arranged aligned and to deform the portion 26 to obtain portions 26 'inwardly shifted, as seen in Figure 1.

  Thus, to manufacture a heat exchange module, such as bundle of tubes 16 connected to at least one header plate 20 provided with crimping means 26; b) preparing at least one secondary heat exchanger 14 having a bundle of tubes 30 connected to at least one header box 32; c) preparing fins 36 (here common fins); d) brazing together the main heat exchanger 12, the secondary heat exchanger 14 and the fins 36; e) preparing the cover 38 (here plastic); and f) crimping the cover 38 on the header plate 20 by means of the crimping means, the latter coming to bear against the peripheral rim 42 of the cover, with the interposition of the seal 44.

  However, as will be seen below, this crimping operation can be tricky to perform, especially on the side of the header plate 20 which is adjacent to the manifold 32 of the secondary heat exchanger.

  FIG. 2 illustrates a second embodiment of the invention which is similar to that of FIG. 1. The main difference here lies in the fact that the bottom 22 of the header plate 20 is completely flat and therefore does not house a groove. 28 as in the case of Figure 1. Here, the seal 44 is placed in a groove which is defined by the ends of the tubes 16 and by the raised edge 24.

  FIG. 3 illustrates a heat exchange module similar to that of FIG. 2, during crimping. In this embodiment, a support member 46 is inserted under the flat bottom 22 of the header plate 20 and between the shown in FIG. 1, the following operations are performed: a) preparing the main heat exchanger 12 with its tubes 16, in the limited space between the bottom 22 and the ends of the corrugated fins (Figure 4).

  FIG. 4 shows in detail the fins 36 with their corrugations or folds 48 which are each brazed against a flat face 50 of a tube 16 and also against a flat face (not visible in FIG. 4). a tube 30.

  To allow its insertion, the support member 46 comprises a core 52 extended by a plurality of teeth 54 which are arranged to engage between the tubes 16 and under the manifold plate 20.

  FIG. 4 also shows the aligned cutouts 56 that comprise the raised edge 24 of the header plate to enable side-deformable portions 26 to be made, as already described above.

  The use of this support member allows the manifold plate 20, and more generally to the entire module, to withstand the significant forces implemented during the crimping operation. In the case of FIGS. 3 and 4, the crimping takes place in a lateral direction, as taught in US Pat. No. 4,331,201.

  However, other types of crimping are possible.

  FIG. 5 illustrates another exemplary embodiment, in which crimping is performed by folded tabs, that is to say by another technique, different from that described above.

  In the case of Figure 5, the bottom 22 of the header plate 20 is extended by a crenellated edge 58 for forming foldable crimping tabs. The manifold plate 20 comprises a first longitudinal side 60 adjacent to the manifold 32 and a second opposite longitudinal side, parallel to the side 60. On the side 60, the manifold plate 20 is provided with tabs 64 already folded, while on the side 62, the collecting plate 20 comprises tabs 66 not yet folded.

  The cover 38 has a peripheral rim 42 which has a first longitudinal side 68 and a second longitudinal side 70, parallel to the first. The first side 68 is engaged under the folded legs 64 by compressing a portion of the seal 44 and the second longitudinal side 70 is brought closer to the header plate (arrow F2) to compress another part of the seal. Then, the legs 66, which were unfolded, are folded against the peripheral flange 70 (arrow F3) to ensure the complete compression of the seal and the seal.

  This solution offers the advantage that the crimping takes place only on the side 62 of the header plate which is the furthest away from the manifold 32 of the secondary heat exchanger 14. In this case, it is advantageous to use also a support member 46 similar to that shown in Figures 3 and 4.

  In the example shown, the crimping is effected by folded tabs, but it could, alternatively, be made by lateral deformation as described above.

  FIG. 6 illustrates another variant embodiment in which the collector plate 20 comprises foldable tabs 72 which are advantageously folded by the use of a wheel 74 rotatably mounted about an axis 76 parallel to the bottom 22 of the collector plate. This wheel 74 comprises a beveled slice 78 which folds the legs 72 as shown.

  Figure 7 shows a heat exchange module in another embodiment of the invention, in which the main heat exchanger 12 and the secondary heat exchanger 14 have respective fins 80 and 82 which are distinct, instead of being common as in the case of fins 36 of the previous embodiments.

  The fins 80 and 82 are also made in the form of corrugated inserts.

  The joining of the respective bundles of the two samplers is carried out here by two common side pieces 84, also called "cheeks", only one of which is visible in FIG. 7. These pieces each consist of a metal plate comprising a flat core. Rectangular 86 having two parallel raised edges 88. The two side pieces 84 are soldered to respective undulations of the fins 80 and 82 at both ends of the module.

  Thus, the heat exchange module of the invention is essentially made by brazing its various components and only the manifold or boxes of the main heat exchanger are subsequently assembled by crimping.

  Although the invention has been described with particular reference to a heat exchange module comprising a main heat exchanger and a single secondary heat exchanger, it can be used for other types of modules comprising, for example, two secondary heat exchangers.

  In addition, although the invention has been described with particular reference to a module comprising an engine cooling radiator and an air conditioning condenser, it can be used with other types of exchangers, in particular with a Charge air cooler of an engine.

Claims (18)

claims   A heat exchange module, comprising a main heat exchanger (12) and at least one secondary heat exchanger (14), each heat exchanger (12; 14) having a tube bundle (16; 30) connected thereto at least one manifold (38; 32), and wherein the respective tube bundles of the heat exchangers are brazed to fins (36; 80,82), characterized in that the manifold (32) of the The secondary heat exchanger (14) is brazed to the tubes (30) of this secondary heat exchanger, while the header of the main heat exchanger (12) includes a header plate (20) brazed to the tubes (16) of the secondary heat exchanger (20). this main heat exchanger and a cover (38) provided with a peripheral flange (42) and crimped on the collector plate (20) by crimping means (26; 64,66; 72) issuing from the collector plate (20; ) and bearing against the peripheral rim (42) of the cover (38).   2. heat exchange module according to claim 1, characterized in that the crimping means comprise a raised edge (24) from the header plate (20) and having side deformation parts (26) able to bear against the peripheral rim (42) of the cover (38).   3. heat exchange module according to claim 1, characterized in that the crimping means comprise a crenellated edge (58) from the header plate (20) and having collapsible parts (64; 66; 72) adapted to bear against the peripheral rim (42) of the cover (38).   4. heat exchange module according to one of claims 1 to 3, characterized in that it comprises a main heat exchanger (12) and a single secondary heat exchanger (14).   5. Heat exchange module according to claim 4, characterized in that the main heat exchanger (12) is a cooling radiator of a vehicle engine, while the secondary heat exchanger (14) is a condenser forming part of a vehicle air conditioning system.   6. Heat exchange module according to one of claims 4 and 5, characterized in that the tubes (16) of the main heat exchanger (12) and the tubes (30) of the secondary heat exchanger (14) are flat tubes.   7. Heat exchange module according to claim 6, characterized in that the fins (36; 80, 82) of the main heat exchanger (12) and / or the secondary heat exchanger (14) are corrugated spacers whose corrugations (48) are brazed to the flat tubes (16; 30).   8. Heat exchange module according to one of claims 1 to 7, characterized in that the main heat exchanger (12) and the secondary heat exchanger (s) (14) have common fins (36).   9. Heat exchange module according to one of claims 1 to 7, characterized in that the main heat exchanger (12) and the secondary heat exchanger (s) (14) have separate fins (80, 82). ).   10. Heat exchange module according to one of claims 1 to 9, characterized in that the main heat exchanger and the secondary heat exchanger (s) have common side parts (84).   11. Heat exchange module according to one of claims 5 to 10, characterized in that the header (32) of the secondary heat exchanger (14) is tubular.   12. heat exchange module according to one of claims 1 to 11, characterized in that the cover (38) is obtained by molding a suitable material which may be a plastic material or a metal material.   13. A method of manufacturing a heat exchange module according to one of claims 1 to 12, characterized in that it comprises the following operations: a) prepare a main heat exchanger (10) having a beam of tubes (16) connected to at least one collecting plate (20) provided with crimping means (26; 64,66; 72); b) preparing at least one secondary heat exchanger (14) comprising a bundle of tubes (30) connected to at least one header (32); c) preparing fins (36; 80, 82) and possibly side pieces (84); d) brazing together the main heat exchanger (12) resulting from operation a), the secondary heat exchanger (14) resulting from operation b) and the fins (36; 80, 82) resulting operation c); e) preparing a cover (38) provided with a peripheral rim (42); and f) crimping the cover (38) on the header plate (20) of the main heat exchanger by means of crimping means which are supported on the peripheral rim (42) of the cover, interposing a seal sealing (44).   14. The method of claim 13, characterized in that the crimping operation f) comprises the lateral deformation of lateral deformation parts (26) that comprises a raised edge (24) from the header plate (20).   15. The method of claim 13, characterized in that the crimping operation f) comprises the deformation of collapsible tabs (64, 66; 72) that comprises a crenellated edge (58) from the collector plate (20).   16. The method of claim 13, characterized in that the crimping operation f) comprises the engagement of a first longitudinal side (68) of the peripheral rim (42) of the cover under folded tabs (64) from a first longitudinal side (60) of the header plate (20), the pivoting of the cover to bring a second longitudinal side (70) of the cover of a second longitudinal side (62) of the header plate, which is provided with folding tabs (66), and folding the collapsible tabs (66) against the second longitudinal side (70) of the peripheral rim of the lid.   17. Method according to one of claims 13 to 16, characterized in that the crimping operation f) comprises the establishment of a support member (46) under the header plate (20) to withstand the efforts of crimping.   18. The method of claim 17, characterized in that the support member (46) comprises teeth (54) arranged to engage between the tubes (16) of the main heat exchanger (14) and under the collector plate (20).