EP3519758A2

EP3519758A2 - Heat exchanger, especially for a motor vehicle

Info

Publication number: EP3519758A2
Application number: EP17787488.0A
Authority: EP
Inventors: José TRINDADE; Xavier Marchadier; Fabien BIREAUD; Rémi TOURNOIS; Valériane HIDDEN
Original assignee: Valeo Systemes Thermiques SAS
Current assignee: Valeo Systemes Thermiques SAS
Priority date: 2016-09-28
Filing date: 2017-09-27
Publication date: 2019-08-07
Also published as: WO2018060623A3; WO2018060623A2; FR3056724A1

Abstract

The invention relates to a heat exchanger (1), especially for a motor vehicle, said heat exchanger (1) comprising: - at least one collector box (20), and - a heat exchange bundle (10) comprising a plurality of tubes (11) opening into the at least one collector box (20) and two side panels (15) arranged on either side of the plurality of tubes (11), the heat exchange bundle (10) being joined by brazing. According to the invention, the heat exchanger (1) further comprises means (60) for mechanically fastening the side panels (15) to the at least one collector box (20).

Description

Heat exchanger, in particular for a motor vehicle

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

Heat exchangers conventionally comprise a heat exchange bundle of tubes and at least one, usually two collector boxes or fluid distribution boxes. In known manner, each manifold comprises at least two parts: a collector plate receiving the ends of the tubes and a cover that caps the collector plate to at least partially close the collector box.

Interlayers or fins may also be provided between the tubes to improve heat exchange.

According to a known solution, the various elements of such a heat exchanger are metallic, for example aluminum or aluminum alloy, and can be assembled and brazed by passing through a brazing furnace, to ensure the joining of all elements.

Such a heat exchanger whose different elements are permanently fixed to each other by a brazing operation is called brazed heat exchanger. With this brazed technology, the tubes can be arranged with a tight pitch, for example of the order of 6 mm. The increase in the number of tubes of the heat exchange bundle makes it possible to improve the performance of the so-called brazed heat exchangers.

In addition, two lateral cheeks may be provided on either side of the heat exchange bundle and are therefore interposed between the two collector boxes. These side cheeks may have interfaces allowing in particular the attachment of the heat exchanger on the vehicle structure or even the attachment of accessories on the heat exchanger. In a brazed heat exchanger, the lateral cheeks are soldered at each end to the collector plate of each collecting box.

However, the heat exchangers are subjected to many mechanical stresses due to the pressure of the fluid passing through it, but also to vibrations and thermal variations during the various operating cycles. In particular, phenomena of expansion and shrinkage related to temperature variations can occur, particularly at the level of the connections between the collector plate and the tubes. These Since the connections are rigid in a brazed heat exchanger, this does not make it possible to compensate for such phenomena of expansion and retraction. Over time, these bonds weaken and breaks and consequently leakage of the fluid can occur.

Similarly, under such conditions, there may appear areas of breaks in the brazed connections between the side cheeks and the collector plates.

Another known technology is a mechanical assembly technology of the elements of the heat exchanger, namely at ambient temperature, for example by crimping, expansion, clipping or other mechanical connection. The mechanical assembly does not include a brazing step of the elements forming the heat exchanger. In particular, each collecting plate may be provided with mechanical fixing means, for example crimping, adapted to cooperate with a peripheral rim of the cover which is fixed on the manifold plate by compressing a seal disposed on the collecting plate. In addition, the ends of the tubes are assembled to each header plate by expanding the ends of the tubes so as to compress the seal between the ends of the tubes and the header plate.

The seal makes it possible to seal between the cover and the header plate but also between the ends of the tubes and the header plate. In addition, the seal makes it possible to compensate for the phenomena of expansion and retraction that may occur. Such a mechanical assembly therefore reduces the risk of leakage of the fluid.

In addition, the collector plates must meet mechanical strength criteria for example during crimping on the lid and pressure and endurance constraints. For this purpose, it is preferable to use metal collector plates, in particular of aluminum or of aluminum alloy.

Moreover, in known mechanical assembly heat exchangers, the header plate is usually provided with flanges through which the ends of the tubes pass. The number of tubes passing through the collector plate is limited by the thickness of the collars, especially when the collector plate and its collars are metallic. The tubes in a mechanical assembly heat exchanger are therefore of lower density than in a brazed heat exchanger. This results in a lower thermal performance in a mechanical assembly heat exchanger compared to a brazed heat exchanger for an equivalent size. The invention therefore aims to at least partially overcome these problems of the prior art by providing a heat exchanger to optimize thermal performance while reducing the risk of leakage and strengthening the connection between the side cheeks and boxes collector.

For this purpose the invention relates to a heat exchanger, in particular for a motor vehicle, said exchanger comprising:

at least one collector box, and

a heat exchange bundle comprising a plurality of tubes opening into said at least one collector and two lateral cheeks arranged on either side of the plurality of tubes.

According to the invention, the heat exchange bundle is assembled by soldering, and said exchanger further comprises means for mechanically fastening the lateral cheeks to said at least one manifold.

Thus, the lateral cheeks of the brazed heat exchange bundle are mechanically assembled to each manifold thus adding a mechanical restraint so as to limit the risk of breakage of connection between the side cheeks of the brazed bundle and the collector boxes, even under conditions of use subjecting the heat exchanger to mechanical stresses of pressure and significant vibrations.

The heat exchanger may further comprise one or more of the following features, taken separately or in combination:

the mechanical fixing means comprise fastening means carried by the lateral cheeks and / or by said at least one collecting box;

the mechanical fastening means comprise inserts assembled on the side flanges and said at least one collector box;

said at least one manifold comprises: a collector plate traversed by the ends of the tubes, and a lid assembled to the collector plate so as to close the collector box,

the mechanical fastening means are configured to mechanically assemble the lateral cheeks to the cover of said at least one manifold;

the lateral cheeks respectively have at least one fastening tab extending in the extension of the corresponding lateral cheek and in the direction of the at least one a collector box,

the mechanical fastening means are configured to mechanically assemble the fastening tabs of the side flanges to the cover of said at least one manifold;

the cover comprises at least one first fastening means, and the fastening tongues respectively comprise at least one second mechanical fastening means complementary to a first fastening means;

said at least one fixing tongue is arranged in abutment against the header plate and at least a portion of the cover;

- The mechanical fastening means are selected from crimping means, latching means, screwing means, riveting means and at least one staple;

the fixing tabs are respectively terminated by crimping tabs configured to be folded against a peripheral edge of the lid;

- The collector plate has a substantially longitudinal shape and extends transversely relative to the tubes;

the mechanical fastening means comprise at least one clip arranged partially around a longitudinal end of the collecting plate and having a housing for receiving said at least one fastening tab;

- Said at least one clip comprises two lateral branches respectively having at one end a flexible detent tab configured to abut against a stop on the cover;

the lateral cheeks extend parallel to the tubes;

said at least one manifold comprises at least one compressible seal arranged at least partially on the collector plate and around the ends of the tubes opening into the collector box;

the tubes are mechanically assembled to the header by flaring the ends of the tubes so as to compress the seal. The seal provides both a sealing function and mechanical connection between the brazed heat exchange bundle and each manifold.

With such a mechanical assembly between the heat exchange bundle and the manifold, the tubes and the lateral cheeks are not brazed with the collector plate of the slip box contrary to the solutions of the prior art, but are mechanically assembled to each manifold, to ensure the resistance to pressure and other mechanical stresses in operation. Other features and advantages of the invention will emerge more clearly on reading the following description, given by way of illustrative and nonlimiting example, and the appended drawings among which:

FIG. 1 is a sloping top-to-bottom view of a heat exchanger according to the invention showing in part a heat exchange bundle and a collector box; FIG. 2 is a partial perspective view showing a first variant; means for mechanically fastening a lateral cheek of the heat exchange bundle to a cover of the header box,

FIG. 3 is a sectional view of FIG. 2;

FIG. 4 is a perspective view of a collector plate of the collector box; FIG. 5a is a partial perspective view showing a second variant of means for mechanically fastening the lateral cheek of the heat exchange bundle to the cover of FIG. the collector box,

FIG. 5b is a partial perspective view showing the cover of FIG. 5a carrying a mechanical fastening means according to the second variant,

FIG. 6a is a partial perspective view showing an exploded mechanical fastening means of the lateral cheek of the heat exchange bundle to the cover of the manifold box according to a third variant,

FIG. 6b is a partial perspective view showing the mechanical fastening means according to the third variant in the assembled state on the lateral cheek and the cover, FIG. 7a is a fragmentary perspective view showing an exploded fastening means. mechanics of the lateral cheek of the heat exchange bundle at the lid of the header box according to a fourth variant,

FIG. 7b is a partial perspective view showing the mechanical fastening means according to the fourth variant in the assembled state on the lateral cheek and the cover; FIG. 8a is a partial perspective view showing an exploded fastening means; mechanics of the lateral cheek of the heat exchange bundle at the cover of the collector box according to a fifth variant, FIG. 8b is a partial perspective view showing the mechanical fixing means according to the fifth variant in the assembled state on the lateral cheek and the cover,

FIG. 9 is a perspective view of a seal of the manifold box; FIG. 10a is a perspective view of a lower face of an internal plate of the manifold box;

FIG. 10b is a perspective view of an upper face of the inner plate of the manifold,

FIG. 10c is an enlarged partial view of a portion of FIG. 10b, and

- Figure 1 Od is a partial view along a section of axis I-I of Figure 10b.

In these figures, the identical elements bear the same references.

The following achievements are examples. Although the description refers to one or more modes or embodiments, this does not necessarily mean that each reference relates to the same mode or embodiment variant, or that the characteristics apply only to a single mode or a single mode. variant embodiment. Simple features of different modes or different embodiments may also be combined or interchanged to provide other embodiments.

In the description, it is possible to index certain elements, such as for example first element or second element. In this case, it is a simple indexing to differentiate and name close but not identical elements. This indexing does not imply a priority of one element with respect to another and it is easy to interchange such denominations without departing from the scope of the present description. This indexing does not imply an order in time either. Heat exchanger

The invention relates to a heat exchanger 1 for a motor vehicle, such as a radiator.

As is partially illustrated in FIGS. 1 to 3, a heat exchanger 1 conventionally comprises a heat exchange bundle 10 comprising a stack of tubes 11 generally alternately with tabs 13, as well as two lateral cheeks 15 on both sides. other of the heat exchange bundle 10.

The heat exchanger 1 also comprises at least one header box 20, generally two collector boxes 20, each comprising a collector plate 21 through which the tubes 11 pass, and a cover 23 intended to be fixed on the collector plate 21 to at least partially close the collector box 20.

The tubes 11 extend longitudinally along a longitudinal axis L _T (FIG. 1) and are mounted between two collecting boxes 20, via the collector plates 21 arranged transversely along the axis T (FIG. 3) with respect to the tubes 11. and respectively traversed by the ends of the tubes 11.

The manifold or boxes 20 can distribute a first fluid to the tubes 11 or collect the first fluid having traveled through these tubes 11. The tubes 11 are therefore intended to be traversed by the first fluid.

The heat exchange bundle 10 is for example intended to be mechanically assembled to the or each manifold 20, by expansion of the ends of the tubes 11 opening into the manifold 20. In this case, the or each manifold box 20 further comprises a seal 25 (Figures 1 and 3). More specifically, it is a compressible seal 25 intended to be arranged on the collecting plate 21 and around the ends of the tubes 11 opening into the manifold 20 to the assembly of the heat exchanger 1.

In addition, when the assembly is mechanical between the tubes 11 and the manifolds 20, in this case, the side flanges 15 are not brazed to the collector plate 21 unlike the solutions of the prior art fully brazed heat exchanger .

Each manifold box 20 may further include an inner plate 27 (Figures 1 and 3) separate from the header plate 21, and arranged at least partially against the seal 25 so as to maintain the seal 25 around the ends of the tubes 11 in the assembled state of the heat exchanger 1. This plate 27 is called "internal plate" because of its arrangement in the interior volume of the manifold 20 defined between the header plate 21 and the cover 23.

Collector box

With reference to FIGS. 1 to 10d, the elements of each collecting box 20 are described in more detail below. Collector plate

With regard to the collector plate 21, reference is made more particularly to FIG. 4. The collector plate 21 has a substantially longitudinal shape and extends along the axis Γ (νοίτ FIG. 3).

A plurality of openings 211 are provided on the header plate 21 for the passage of the ends of the tubes 11 of the heat exchange bundle 10. In the example illustrated, the shape of these openings 211 is complementary to the shape of the ends of the tubes 11 before they are flared. For example, the openings 211 are substantially oblong, and extend longitudinally substantially transversely to the longitudinal axis LT of the tubes 11 in the assembled state of the heat exchanger 1.

According to the illustrated embodiment, the manifold plate 21 further comprises fastening means 213 to the lid 23. This is mechanical fastening means 213, such as crimping tabs can be folded on the cover 23 .

For example, the header plate 21 has a peripheral edge 215 having these fastening means 213. In this example, the header plate 21 can be folded over its periphery to form the peripheral edge 215.

The crimping lugs 231 may be provided on the entire periphery of the peripheral rim 215 or alternatively only on certain sides, for example only on the long sides.

Furthermore, according to the illustrated embodiment, the header plate 21 is substantially flat and free of collar, more precisely it comprises a bottom 217 flat and devoid of collar, in which are formed the openings 211 and relative to which the peripheral edge 215 is elevated.

In addition, according to this embodiment, the header plate 21 has no groove, groove or the like to accommodate the seal 25. Alternatively, the header plate 21 could have a groove or groove to accommodate at least a portion sealing gasket 25 serving to seal between the cover 23 and the collector plate 21.

Lid

Referring again to FIGS. 1 to 3, the cover 23, for its part, is assembled on the collector plate 21 and has a principal longitudinal extension direction substantially transverse to the longitudinal axis LT of the tubes 11 in the state assembled exchanger 1. The cover 23 has in the illustrated example two large opposite longitudinal sides, two opposite small side sides, and a substantially arch form connecting the four sides.

The cover 23 may be made of plastic according to the embodiments described with reference to Figures 1 to 8b. In this case, it is the compression of the seal 25 which provides a tight connection between the cover 23 and the collector plate 21.

Each cover 23 generally has one or more connectors 230 'for connecting the heat exchanger 1, by way of non-limiting example, a circuit of the first fluid or a drain circuit. Such connectors 230 'are known to those skilled in the art and are not detailed herein.

In addition, the lid 23 has a cover foot 231 intended to be fixed to the header plate 21, for example by means of the crimping tabs 213 of the header plate 21 which are crimped onto the cover foot 231 at the assembly (see FIG. Figures 1 to 3, 5a and 6a to 8b). The term "cover foot", the lower portion of the cover 23 which is on the side of the heat exchange bundle 10 assembly. This cover foot 231 thus forms a peripheral rim. The cover foot 231 then bears against the seal 25, more precisely against a peripheral portion of the seal 25, between the cover 23 and the collector plate 21 during crimping.

Different variants of the lid 23 are shown in Figures 1 to 3 and 5a to 8b. These alternative embodiments are complementary variants of embodiment of the side cheeks 15 which will be described in more detail later.

According to the variant embodiments illustrated in FIGS. 5a to 8b, the cover 23 may comprise a first fastening means 232; 233; 234; 235 which can be configured to cooperate with a second complementary fastening means 152; 153; 154 carried by a side cheek 15 and / or with an insert as will be described in more detail later.

The first attachment means 232; 234; 235 (Figures 5a to 8b) may be formed on or integral with the cover 23.

According to an alternative embodiment illustrated in FIGS. 5a, 5b, the cover 23 comprises a snap-in means such as a clip or a detent tab 232. According to another embodiment shown in Figures 6a and 6b, the cover 23 may carry a nut 233 for a screw connection. Alternatively, the cover 23 could have an internal thread.

According to yet another variant illustrated in Figures 7a and 7b, the cover 23 may have fixing walls 234 provided with holes and configured to allow assembly by riveting.

Finally, according to a variant illustrated in FIGS. 8a and 8b, the cover 23 may comprise at least one pin or locking pin 235, for example integral with the cover 23, and forming an outgrowth or protrusion on the cover 23.

These different variants of the fastening means carried by the cover 23 as well as their interaction with the lateral cheeks 15 for assembling the side cheeks 15 to the cover 23, will be detailed later.

Seal

The seal 25, better visible in Figure 9, is for example made of elastomer such as an ethylene-propylene-diene monomer known under the acronym EPDM.

The seal 25 is arranged to be compressed between the ends of the heat exchange tubes 11 and the inner plate 27, in the assembled state of the heat exchanger 1 (see Figures 1 and 3).

According to the embodiment illustrated in Figures 1 and 3, the seal 25 comprises at least two parts: a first peripheral portion 251 shaped to follow the periphery of the header plate 21, and a second portion 253, 254, 255 configured to surround the tube ends 11 at the assembly of the heat exchanger 1.

The first peripheral portion 251 seals between the cover 23 and the header plate 21. With reference to FIGS. 1, 3 and 9, the second portion 253, 254, 255 of the seal 25 comprises a plurality of collars 253, hereinafter called standard collars defining openings 254 for the passage of the tubes 11 and extending towards the cover 23 to the assembly of the manifold 20. The standard collars 253 are intended to be received in the internal plate 27 .

In addition, these standard collars 253 are adapted to receive the ends of the tubes 11 at the assembly of the heat exchange bundle 10 with a collector plate 21. More precisely, the standard collars 253 extend in the same direction as the insertion direction of the tubes 11 into the collector plate 21.

In addition, the shape of the standard flanges 253 is complementary to that of the ends of the tubes 11. In the example illustrated in FIG. 9, the standard collars 253 have, in cross section, a substantially oblong shape before assembly of the manifold 20 The standard collars 253 are intended to be compressed during the expansion of the ends of the tubes 11. The seal between the tubes 11 and the collector plate 21 is ensured by this compression of the standard collars 253 around the ends of the tubes 11.

Furthermore, with reference again to FIGS. 1 and 3, the second part of the seal 25 may also comprise a plurality of inverted collars 255, extending opposite the standard collars 253 and made in the extension of the standard collars 253.

The inverted collars 255 extend through the openings 211 of the collector plate 21 when the seal 25 is arranged on the collector plate 21.

These inverted collars 255 are also adapted to receive the ends of the tubes 11 at the assembly of the heat exchange bundle 10 at the manifold 20. In addition, the shape of the inverted collars 255 is also complementary to that of the tubes 11, for example substantially oblong.

The standard collars 253 and the inverted collars 255 extend in a direction parallel to the longitudinal axis of the tubes 11 in the assembled state of the heat exchanger 1. Finally, the standard collars 253 and the inverted collars 255 are flexible and adapt to the shape of the tubes 11 and the openings 211 of the collector plate 21. Thus, the seal 25, in particular its standard collars 253 and inverted 255, provides a flexible connection between the collector plate 21 and the tubes 11, which makes it possible to absorb the stresses of deformation related to the thermal expansion. The seal 25 further includes in this example a base 257, best seen in Figure 9, from which extend on one side the standard collars 253 and the opposite side the inverted collars 255. The base 257 connects the peripheral portion 251 to these standard collars 253 and inverted collars 255. In addition, the base 257 is arranged between the collector plate 21 and the inner plate 27. Internal plate

With reference to FIGS. 10a to 10d, the internal plate 27 is described in more detail. advantageously made of plastic.

The inner plate 27 has for example a generally parallelepipedal shape, here parallelepiped rectangle.

This inner plate 27 comprises a plurality of openings 271 for receiving the ends of the tubes 11 and the seal 25 around the ends of the tubes 11, more precisely the standard collars 253 of the seal 25. The shape of the openings 271 is adapted to the shape of the standard collars 253 and the ends of the tubes 11. In this example, the openings 271 are substantially oblong and extend longitudinally substantially transversely to the longitudinal axis of the tubes 11 in the assembled state of the Heat exchanger 1. Of course, any other form complementary to the shape of the standard flanges 253 of the gasket 25 and the ends of the tubes 11 may be provided.

With the exception of openings 271, the inner plate 27 is substantially planar.

Furthermore, the inner plate 27 is arranged so that the seal 25 is compressed between each tube end 11 and the inner plate 27, during the mechanical assembly of the tubes 11 to the manifold 20. More specifically, it is the standard protruding collars 253 of the seal 25 which are compressed.

The inner plate 27 has a lower face 27a (FIGS. 1 and 10a) intended to be arranged opposite the base 257 of the seal 25 and an opposite upper face 27b (FIGS. 1 and 10b to 10d) arranged opposite the cover 23, the assembly of the manifold 20. The inner plate 27 is arranged between the base 257 of the seal 25 and the cover 23.

Furthermore, as is best seen in Figures 10b to 10d, the inner plate 27 may be deformed locally around the openings 271. More specifically, the inner plate 27 is locally deformed only on the upper face 27b.

The inner plate 27 thus has local deformations 273 provided so that the edge of the openings 271 acts as counter-form complementary to the shape of the ends of the tubes 11 after expansion. The local deformations 273 of the inner plate 27 are for example made by flares 273. Thus, according to the embodiment described, during the assembly of the tubes 11 to the collector plate 21, the ends of the tubes 11 are flared so that to follow the shape of the borders delimiting the openings 271 of the inner plate 27. The inner plate 27 and the seal 25 may be two separate pieces, or alternatively may be made in one piece bi-materials, for example by co-molding.

Heat exchange bundle

Referring again to FIGS. 1 to 3, 5a and 6a to 8b, the heat exchange bundle 10 of the heat exchanger 1 is described in more detail below.

This is a heat exchange bundle 10 assembled by brazing, that is to say whose various elements are assembled together and then brazed by passing through a brazing furnace, to ensure the joining of all elements of the heat exchange bundle 10. For this purpose, the various elements of the heat exchange heat exchanger bundle 10 are metallic, preferably aluminum or aluminum alloy.

tubing

The tubes 11 of the heat exchange bundle are made from a metal sheet or strip. The sealing of each tube 11 can be provided by soldering. For example the tubes 11 are formed by folding, so-called "folded tube", or they can be stapled or it can be electro-welded tubes.

According to the embodiment illustrated in Figure 3, the cross section of a tube 11 may have two parallel fluid circulation channels juxtaposed 111 and separated by at least one partition 113, also called leg forming spacer. For example, each tube 11 may have a cross section substantially "B". Of course, any other type of folding can be provided. As an alternative, other sections may be provided, for example of substantially oblong shape defining a single channel 111 for fluid circulation.

In addition, as previously said, the brazed heat exchange bundle 10 is intended to be mechanically assembled to the or each manifold 20. The heat exchanger 1 is in this case called a mechano-brazed exchanger.

To do this, the tubes 11 are mechanically assembled to each manifold 20, so as to pass through the manifold plate 21, the seal 25 and the inner plate 27. The ends of the tubes 11 opening into this manifold 20 are then plastically deformed. According to the embodiment described, this mechanical assembly is by expansion or flaring of the ends of the tubes 11. For this purpose, the ends of the tubes 11 are flared so as to bear on the seal 25 (FIGS. 1 and 3). ) of the manifold box 20. The flaring of the tube ends 11 is for example made by punching these ends. Preferably, the flare is made localized. By localized evaporation, it is meant that the flaring is not carried out over the entire periphery of the end of a tube 11. In other words, the flaring is carried out on one or more portions of the end of the tube 11.

It is possible to flare at least locally the ends of the tubes 11, so as to define one or more flares 115 on the periphery of the ends of the tubes 11. The flares 115 on the peripheries of the ends of the tubes 11 form bearing zones on the seal 25.

In a variant, it is also possible to provide one or more other so-called internal flares 117 made on the side of the remainder of the heat exchange bundle 10, or on the inside of the heat exchange bundle 10, as can be seen in FIG. .

At the flares 115, 117 the width of the ends of the tubes 11 increases. The flares 115, 117 allow the gasket 25 to be compressed in order to guarantee the seal between the collector plate 270 and the tubes 11.

The heat exchanger 1 may advantageously comprise one or more locking members (not shown) arranged at the end of one or more tubes 11 so as to maintain the flare (s) 115, and thus maintain the compression of the gasket. sealing 25.

Dividers

Furthermore, in this example, the spacers 13 (see Figures 1 to 3) separate the tubes 11 from each other, and are intended to be traversed by a second fluid for a heat exchange with the first fluid for passing through the tubes 11 The disturbance generated by the presence of these spacers 13 facilitates the heat exchange between the two fluids. These spacers 13, shown schematically in Figures 2 and 3, may have a substantially corrugated shape as shown in Figure 1. The spacers 13 are for example brazed to the tubes 11 at the vertices of their corrugations. These spacers 13 are well known to those skilled in the art and are not described in more detail herein.

Lateral cheeks

The two lateral cheeks 15 are arranged on either side of the plurality of tubes 11, in this example on either side of the alternating stack of tubes 11 and The lateral flanges 15 extend longitudinally parallel to the tubes 11.

According to the variant embodiments illustrated in FIGS. 1 to 5a and 6a to 8b, the lateral cheeks 15 respectively have at least one fastening tab 150. In particular, each lateral cheek 15 has two fastening tabs 150 each extending from a longitudinal end of the corresponding lateral cheek 15, in the extension of this side cheek 15.

Each fastening tab 150 extends towards an associated collecting box 20, more precisely in the direction of the cover 23, at the assembly of the heat exchanger 1. In other words, each fastening tab 150 extends to opposite the rest of the heat exchange bundle 10.

More precisely, according to the embodiments illustrated in FIGS. 1 to 5a and 6a to 7b, each fastening tab 150 is arranged in abutment against the collecting plate 21 and at least one portion 231 of the cover 23, and is advantageously shaped so as to following the contour of the header plate 21 and at least a portion of the cover 23, in particular the cover foot 231.

To do this, each attachment tab 150 may have a substantially "L" shape extending from a longitudinal end of a side cheek 15. In other words, each attachment tab 150 has a substantially bent or folded shape substantially at right angles, the bend being complementary to the contour 215, 217, the header plate 21 described in more detail later. Thus, as can be seen more clearly in FIG. 3, each fastening tab 150 may have:

a first portion 150a extending opposite and parallel to the bottom 217 of the header plate 21 and

a second portion 150b extending opposite and in parallel with the peripheral edge 215 raised from the collecting plate 21.

More specifically, the second portion 150b of each fastener tab 150 extends opposite a small side of the peripheral edge 215 of the header plate 21.

Of course, the fixing tabs 150 come into contact with this contour 217, 215 of the header plate 21. Mechanical fastening means

According to the embodiments illustrated in Figures 1 to 8b, the heat exchanger 1 further comprises fastening means 60 of the side flanges 15 to each manifold 20. This is mechanical fastening means 60.

The mechanical fastening means 60 between the lateral cheeks 15 and the cover 23 make it possible to lock the mechanical assembly between the heat exchange bundle 10 and the manifold 20. Particularly according to the particular embodiment of the tubes 11 with a double flare , the mechanical fastening means 60 are complementary to the flaring formed on the periphery of the ends of the tubes 11 for mechanical retention.

The mechanical fixing means 60 may be definitive, that is to say not removable or fixed, or alternatively it may be mechanical fastening means 60 removable or removable.

In addition, the mechanical fixing means 60 are carried by the lateral cheeks 15 and / or by the cover 23 of each manifold 20. When mechanical fastening means 60 are carried by the lateral cheeks 15, they are advantageously worn by the fastening tabs 150.

Alternatively or additionally, the mechanical fixing means 60 may comprise one or more inserts 61 (FIGS. 6a, 6b), 62 (FIGS. 7a, 7b), 63 (FIGS. 8a, 8b) for locking between a lateral cheek 15 and a cover 23.

Non-exhaustively, the mechanical fastening means 60 may allow assembly by crimping, snapping, screwing, riveting, stapling, or by plastic deformation, or any combination of such assemblies.

According to the alternative embodiments shown in FIGS. 1 to 7b, each fastening tab 150 may carry at least one second mechanical fixing means 151; 152; 153; 154 configured to cooperate with the cover foot 231 and / or with a first complementary fastening means 232; 233; 234 carried by the lid 23.

With reference to FIGS. 1 to 7b, the second mechanical fixing means 151; 152; 153; 154 may be formed on or integrally with the lateral cheeks 15, and in particular on the fastening tabs 150 of each side cheek 15. According to a first variant illustrated in FIGS. 1 to 3, the mechanical fixing means 60 are crimping means. In this case, the lateral cheeks 15 may comprise crimping tabs 151 configured to be folded down on the lid 23, more precisely on the lid base 231, at the assembly of the heat exchange bundle 10 to the manifold 20. More specifically, each fastening tab 150 of a lateral cheek 15 has such crimping tabs 151. The crimping tabs 151 are formed in the extension of each fastening tab 150, in particular of the second part 150b, and come from In other words, the securing tabs 150 are respectively terminated by the crimping tabs 151 configured to be folded or bent against the cover leg 231.

In order to fold down such crimping tabs 151 on the lid base

231, the crimping tabs 213 on the short sides of the collector plate 21 are sufficiently spaced apart for the passage of the crimping lugs 151 of each side cheek 15. Such spacing between the crimping lugs 213 on the short sides is better visible on Figure 4. Alternatively, it can be provided that the manifold plate 21 does not have crimping tabs 213 on its short sides.

According to a second variant illustrated in FIGS. 5a and 5b, the mechanical fastening means 60 comprise latching means.

In this case, the lateral cheeks 15 may respectively comprise a housing 152 intended to receive a clip or a latching lug 232 of the cover 23, specifically made of (e) material with the cover foot 231, when the beam of heat exchange 10 is assembled to the manifold 20, according to the mounting direction shown schematically by the arrow F in Figure 5a.

The housing 152 may be provided on the second portion 150b of each fastening tab 150.

Each latching lug 232 is in the form of a protruding member with respect to the wall of the lid 23 on which it is arranged, as is best seen in Figure 5b.

According to the illustrated example, the latching lug 232 has an inclined ramp 232a. More precisely it is a ramp 232a oblique with respect to the axis of extension of the second portion 150b of the fastening tab 150 which cooperates with the latching lug 232. In this example, the second part 150b of the fastening tab 150 extends parallel to the tubes 11, the ramp 232a is oblique with respect to the longitudinal axis Lj. The ramp 232a is also oblique with respect to the transverse axis along which the collecting plate 21 extends.

In this particular example, the ramp 232a has an upward inclination according to the mounting direction shown schematically by the arrow F in FIG. 5a, so as to raise the fastening tab 150 before the latching tab 232 is inserted into the 152, to ensure the mechanical locking between the side cheek 15 and the lid 23.

Of course, alternatively the housing may be provided on the cover 23 and the clip or the latching lug may be provided on each side flange 15, in particular on the fixing tabs 150.

Furthermore, similarly to the first variant, the collector plate 21 may have on its short sides crimping tabs 213 spaced apart sufficiently to allow the passage of the fastening tab 150 to snap onto the tab of snap 232 complementary or may not have crimping tabs 213 on its short sides.

According to a third variant illustrated in FIGS. 6a and 6b, the mechanical fixing means 60 comprise screwing means 61. At least one screw 61 / nut 233 assembly can be provided, the nut 233 being mounted in the cover 23, more precisely in a wall of the cover 23 arranged opposite the fixing tongue 150. In a variant, the cover 23 could have an internal thread. According to this third variant, the fixing tongue 150 has at least one hole 153 for the passage of the associated screw 61. The hole 153 may have a substantially oval shape so as to allow adjustment during screwing. In particular, the hole 153 is formed in the second portion 150b of the attachment tab 150 in the shape of "L".

Furthermore, similarly to the first and second variants, the header plate 21 may have on its short sides crimping tabs 213 spaced apart sufficiently, or may not have crimping tabs 213 on its short sides, so as to allow the passage of the fixing tongue 150 to be screwed on the lid 23.

According to a fourth variant illustrated in FIGS. 7a and 7b, the mechanical fastening means 60 comprise riveting means 62. In this case, each fastening tab 150 has one or more holes 154 for the passage of the riveting means 62. As can be seen in FIGS. 7a and 7b, the shape of the end of each fastening tab 150 can be adapted for producing these holes 154. In this example with two holes 154, the end of the fastening tab 150 can be enlarged. In particular, the second portion 150b of the fastening tab 150 may have a substantially "T" shape.

In addition, according to the particular example illustrated in FIGS. 7a and 7b, the cover 23 may comprise on each side cooperating with a fastening tongue 150, a fixing wall 234 of complementary shape to the shape of the end of the tongue. associated fastener 15, which is disposed opposite this fastening tab 150 and similarly has holes (not visible) for the passage of the riveting means 62. Each fixing wall 234 is here provided to allow the access to the opposite side of the riveting means 62 so as to be able to deform the riveting means 62.

Furthermore, similarly to the first three variants, the header plate 21 may have on its short sides crimping tabs 213 spaced apart, or may not have crimping tabs 213 on its short sides, so as to allow the passage of the fixing tongue 150 and allowing riveting between this fixing tongue 150 and the complementary fixing wall 234 of the cover 23 to be carried out.

According to a fifth variant illustrated in FIGS. 8a and 8b, the mechanical fixing means 60 comprise at least one attached fastening member such as a clip 63 intended to cooperate with both a fastening tab 150 of a lateral cheek 15 and the lid 23.

The staple 63 is for example a piece of plastic material.

This clip 63 is for example assembled in a translational movement. According to the embodiment described with reference to FIGS. 8a and 8b, during assembly, the staple 63 is slipped around the fixing tab 150, the collecting plate 21 and the cover foot 231 (not visible in FIGS. 8b) housed in the space delimited by the raised peripheral edge 215 of collecting plate 21. In other words, this clip 63 is partially arranged around a longitudinal end of the collecting plate 21.

In the assembled state (FIG. 8b), the staple 63 abuts against one or more pins or locking lugs 235 provided on the cover 23. These pins or locking lugs 235 thus form stops. With reference to FIG. 8a, the staple 63 is inserted in one direction assembly substantially perpendicular to the longitudinal axis L _T of the tubes 11, and substantially parallel to the transverse axis T.

To do this, according to the particular example illustrated, the staple 63 has guiding elements such as rails 630 allowing it to slide relative to the collector plate 21.

In addition, the clip 63 has a housing 631 configured to receive the attachment tab 150, as shown in Figure 8b. In this example, it is a slot 631 of complementary shape to the attachment tab 150, here the slot 631 is longitudinal.

More specifically, the clip 63 has a generally "U" -shaped general shape with a base 632 from which two parallel lateral branches 633 extend. The housing 631 for receiving the fixing tab 150 is, in this example, formed in the base 632.

In the mounted state, the lateral branches 633 enclose the header plate 21 vis-a-vis.

In addition, each side branch 633 has, at its end opposite the base 632, a latching lug 634 configured to cooperate with the associated locking lug 235 on the cover 23 to maintain locked in position the assembly once mounted . For this purpose, the detent tabs 634 are flexible so that they can be brought closer to the corresponding lateral branch 633 during insertion until they pass the corresponding locking lug 235, and so as to be able to abut against the locking lug 235, in particular against a lower surface of this locking lug 235 at the end of the assembly.

Furthermore, similarly to the four previous variants, the header plate 21 does not have crimping tabs 213 on its short sides, so as to allow the passage of the clip 63 until the flexible snap tabs. 634 abut against the locking lugs 235.

Method of assembling the heat exchanger

With reference to all the figures, a method of assembly of a heat exchanger 1 as described above is described below.

The method comprises a step of assembling the heat exchange bundle 10 followed by a brazing step of the heat exchange bundle 10 by passing through a dedicated furnace. For the assembly of the heat exchange bundle 10 (see FIG. 1), a plurality of tubes 11 are stacked. According to the embodiments shown, tubes 11 and tabs 13 are stacked alternately, then two cheeks are assembled. lateral 15 on either side of the stack of tubes 11 and spacers 13.

The heat exchange bundle 10 assembled can be brazed.

For the assembly of a manifold 20, a seal 25 is provided on a manifold plate 21, so that the inverted flanges 255 of the seal 25 are inserted into the openings 211 of the manifold plate 21 ( see Figures 1 and 3).

An inner plate 27 is then provided, so that the standard flanges 253 of the gasket 25 extend through the openings 271 of the inner plate 27. If the gasket 25 and the inner plate 27 are made of one piece, we have this unique piece in one step.

The brazed heat exchange bundle 10 is assembled at each end to a subassembly comprising a header plate 21, a seal 25, and an inner plate 27. The ends of the heat exchange tubes 11 of the bundle Brazed heat exchange is inserted through a header plate 21, a seal 25 and an inner plate 27, so that the standard collars 253 of the seal 25 are arranged around the protruding ends of the tubes 11.

For the mechanical assembly of the heat exchange bundle 10 to the header box 20, the ends of the tubes 11 are flared so as to compress the seal 25. The ends of the tubes 11 may be flared, for example a first time thus forming an internal flare 117 (see FIGS. 1 and 3) so as to compress the seal 25 against the collecting plate 21. The ends of the tubes 11 are advantageously flared again thus forming one or more external flares 115 so as to compressing the seal 25, more precisely its standard collars 253, against the inner plate 27.

Then, the cover 23 is placed in such a way that the cover foot 231 is housed in the space delimited by the raised peripheral edge 215 of the collecting plate 21 while coming on the peripheral part 251 of the seal 25.

After that, the lid 23 is assembled to the header plate 21, for example by crimping by folding the crimping tabs 213 of the header plate 21 on the cover foot 231, which ensures the compression of the seal 25, more precisely of its peripheral portion 251.

Mechanical assembly is also performed between the lateral cheeks 15 and the cover 23 of each manifold 20, for example by crimping by folding the crimping lugs 151 of the lateral cheeks 15 on the base of cover 231, or by means of cooperation. snap-on 152, 232 carried on the one hand by the lateral cheeks 15 and on the other by the cover 23, or by screwing the fastening tongues 150 of the lateral cheeks 15 on the cover 23, or with the aid of riveting means 62 or staples 63.

Of course, the order of some steps of this process can be reversed.

Thus, optimized thermal performance is achieved thanks to the heat exchange bundle 10 brazed with tubes 11 having a tight pitch, to the thermal shock resistance on the side of the collector plate 21 thanks to the mechanical assembly between the tubes 11 of this brazed beam and the collector plate 21.

The seal 25 provides both a function of mechanical connection between the heat exchange bundle 10 brazed and the manifold 20, but also a sealing function of the manifold 20 and between the tubes 11 and the plate collector 21.

In addition, the mechanical holding means 60 compensate for the absence of soldering between the lateral cheeks 15 and the collecting plates 21, and make it possible to prevent the lateral cheeks 15 from sliding with respect to the remainder of the heat exchange bundle 10 in operation. . The mechanical holding means 60 add a mechanical restraint.

Moreover, when the mechanical fastening means 60 are directly integrated with the cover 23 and / or the lateral cheeks 15, this avoids the use of an additional piece or tool and makes it possible to overcome a mounting.

Claims

1. Heat exchanger (1), in particular for a motor vehicle, said exchanger (1) comprising:

at least one manifold (20), and

a heat exchange bundle (10) comprising a plurality of tubes (11) opening into said at least one manifold (20) and two lateral flanges (15) arranged on either side of the plurality of tubes (11),

characterized in that

the heat exchange bundle (10) is assembled by soldering, and in that

said exchanger (1) further comprises mechanical fastening means (60) of the lateral cheeks (15) to said at least one manifold (20).

2. Heat exchanger (1) according to the preceding claim, wherein the mechanical fixing means (60) comprise fastening means (151, 152, 153, 154; 232, 233, 234, 235) carried by the lateral cheeks ( 15) and / or by said at least one manifold (20).

3. Heat exchanger (1) according to one of the preceding claims, wherein the mechanical fastening means (60) comprise inserts (61, 62, 63) assembled on the side flanges (15) and said at least one box collector (20).

4. Heat exchanger (1) according to one of the preceding claims, wherein:

said at least one manifold (20) comprises:

A collecting plate (21) traversed by the ends of the tubes (11), and

A cover (23) assembled to the header plate (21) so as to close the header (20), and in which

- The mechanical fastening means (60) are configured to mechanically assemble the side flanges (15) to the cover (23) of said at least one manifold (20).

5. Heat exchanger (1) according to the preceding claim, wherein:

the lateral cheeks (15) respectively have at least one fixing tongue (150) extending in the extension of the corresponding lateral cheek (15) and in the direction of the said at least one collecting box (20), and in which the mechanical fixing means (60) are configured to mechanically assemble the fastening tongues (150) of the lateral cheeks (15) to the cover (23) of the at least one manifold (20).

6. Heat exchanger (1) according to claims 2 and 5, wherein:

the cover (23) comprises at least a first attachment means (232; 233; 234;

235), and wherein

the fixing tongues (150) respectively comprise at least one second mechanical fastening means (152; 153; 154) complementary to a first fastening means (232; 233; 234).

7. heat exchanger (1) according to claim 5 or 6, wherein said at least one fastening tab (150) is arranged in abutment against the header plate (21) and at least a portion (231) of the cover (23). .

8. Heat exchanger (1) according to any preceding claim, wherein the mechanical fixing means (60) are selected from crimping means (151), latching means (152, 232), screwing means (61), riveting means (62) and at least one staple (63).

The heat exchanger (1) according to claims 2, 5 and 8, wherein the securing tongues (150) are respectively terminated by crimping tabs (151) configured to be folded against a peripheral edge (231) of the lid (150). 23).

10. Heat exchanger (1) according to claims 3, 5 and 8, wherein:

the collecting plate (21) has a substantially longitudinal shape and extends transversely with respect to the tubes (11), and in which

the mechanical fastening means (60) comprise at least one staple (63) arranged partially around a longitudinal end of the collecting plate (21) and having a receiving housing (631) of said at least one fixing tongue (150). ).

11. Heat exchanger (1) according to the preceding claim, wherein said at least one staple (63) comprises two lateral branches (633) respectively having at one end a flexible detent tab (634) configured to abut against a stop (235) on the cover (23).

12. Heat exchanger (1) according to any one of the preceding claims, wherein the side flanges (15) extend parallel to the tubes (11).

13. Heat exchanger (1) according to claim 4 taken in combination with any one of the preceding claims, wherein:

said at least one manifold (20) comprises at least one compressible seal (25) arranged at least partially on the collector plate (21) and around the ends of the tubes (11) opening into the collector box (20), and in which

the tubes (11) are mechanically assembled to the manifold (20) by flaring the ends of the tubes (11) so as to compress the seal (25).