WO2018060638A1

WO2018060638A1 - Heat exchanger, in particular for a motor vehicle

Info

Publication number: WO2018060638A1
Application number: PCT/FR2017/052650
Authority: WO
Inventors: José TRINDADE; Xavier Marchadier; Fabien BIREAUD; Rémi TOURNOIS; Valériane HIDDEN
Original assignee: Valeo Systemes Thermiques
Priority date: 2016-09-28
Filing date: 2017-09-28
Publication date: 2018-04-05
Also published as: FR3056734A1; FR3056734B1

Abstract

The invention concerns a heat exchanger (1), comprising: - at least one header box (20) comprising a header plate (21), - a heat exchange bundle (10) comprising a plurality of tubes (11), the tubes (11) respectively comprising at least one end opening into the header box (20) and having at least one flaring (115), and - at least one compressible seal (25, 25') arranged at least partially on the header plate (21) and around the ends of the tubes (11) opening into the header box (20). According to the invention, the heat exchanger (1) also comprises at least one locking member (29) arranged at least partially inside the end of at least one tube (11) and shaped to retain the flaring (115) of the end of said tube (11) in order to compress the seal (25, 25').

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.

However, heat exchangers are subject to many stresses and thermal variations during the different 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 connections being rigid in a brazed heat exchanger, this does not compensate for such phenomena of expansion and retraction. Over time, these bonds weaken and breaks and consequently leakage of the fluid can occur.

Another known technology is a mechanical assembly technology of heat exchanger elements, ie at ambient temperature, for example by crimping, expansion, clipping or other mechanical connection. 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 header plate by compressing a seal disposed on the header 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.

However, the tubes of the heat exchange bundle must meet mechanical resistance criteria, for example pressure constraints exerted by the seal.

In addition, the known flexible connections made thanks to the seal for the mechanical exchangers can not in the state be applied for brazed exchangers because these connections present the risk of a too weak mechanical resistance with the tubes of the brazed exchangers , such as bent tubes. Indeed, these tubes may close under the effect of the pressure exerted by the seal. In such a case, the tubes are then no longer mechanically retained, and can move, thus ensuring no longer sealing between the heat exchange bundle and the manifold. The invention therefore aims to at least partially overcome these problems of the prior art by providing a heat exchanger to meet pressure and endurance constraints while reducing the risk of leakage.

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

at least one collector box comprising a collector plate,

a heat exchange bundle comprising a plurality of tubes, the tubes respectively comprising at least one end opening into the collecting box and having at least one flare, and

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.

According to the invention, said exchanger further comprises at least one locking arranged at least partially within the end of at least one tube and shaped to maintain the flare of the end of said tube to compress the seal.

The locking members inserted at the end of one or more tubes make it possible to lock the flares of the tubes so as to keep the gasket compressed by the tubes, thereby guaranteeing the mechanical strength.

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

the collector box is mechanically assembled to the heat exchange bundle of said exchanger;

the tubes have in cross section two half-sections separated by a partition, and two locking members are inserted on a tube end, so that each locking member is inserted on a half-section of the tube;

said heat exchanger comprises a plurality of regularly distributed locking members;

said heat exchanger comprises at least one locking member for each tube end;

said at least one locking member is formed on an element of the heat exchanger;

- The manifold further comprises a lid assembled to the header plate so as to close the manifold, and said at least one locking member is formed as a tongue integrally with the cover extending in the direction of the tubes and inserted at least partially within a tube end;

the lid comprises at least one tie rod integrally with the lid and extending into the interior volume of the lid, and the tongue extends from said at least one tie rod towards a tube end;

the lid has a substantially longitudinal shape;

said at least one tie rod extends in the longitudinal direction of the lid;

said at least one tie extends transversely in the interior volume of the lid; the tongue has an end of complementary shape to the at least partially flared shape of the end of a tube, for example a substantially trapezoidal shape; the manifold further comprises an inner plate separate from the header plate and arranged at least partially against the seal, so that the seal is interposed between the header plate and the inner plate;

the inner plate has a plurality of flanged openings forming a plurality of locking members, the flanges extending towards the tubes and being arranged on the periphery of the ends of the tubes, so as to maintain the seal compressed between each tube end and the collector plate;

the collars of the inner plate have a plastic deformation, complementary to the ends of the tubes, so as to maintain the flares of the ends of the tubes bearing against the seal;

the inner plate is arranged between the seal and the lid;

said at least one locking member is an additional piece attached to the elements of the heat exchanger and assembled on a tube end; said at least one locking member is mechanically joined within a tube end;

said at least one locking member is in the form of an inner ring;

the inner ring has a thickness of the order of 0.15mm to 0.30mm;

the inner ring has an outer perimeter substantially equal to the inner perimeter of the end of a tube before flaring;

- The tubes respectively have an internal flare and an external flare, and the inner ring has an outer perimeter substantially equal to the inner perimeter at the internal flare of the end of a tube;

the inner ring has at least one chamfer shaped to facilitate insertion of the inner ring within a tube end;

said at least one locking member is made of a metallic material, such as aluminum or aluminum alloy;

the heat exchange bundle is assembled by soldering.

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:

- Figure 1 is a sectional view from top to bottom in slice of a heat exchanger according to a first embodiment partially showing a heat exchange bundle and a collector box,

FIG. 2 is a perspective view of the heat exchanger of FIG. 1 on which the cover of the manifold box has been removed and showing locking members according to a first variant;

FIG. 3 is an enlarged portion of FIG.

FIG. 4 is a fragmentary view with a cutaway at the lid, showing a second embodiment of the locking members on the cover of the heat exchanger of FIG. 1;

FIG. 5 is a partial view showing another arrangement of the locking members according to the second embodiment variant,

FIG. 6a is a cross-sectional view of a bent tube for a heat exchanger,

FIG. 6b is a cross-sectional view of a stapled tube for a heat exchanger,

FIG. 7 is a perspective view partially showing a heat exchanger according to a second embodiment,

FIG. 8 is a perspective view of a collecting plate of a collecting box of the heat exchanger according to the second embodiment,

FIG. 9a is a perspective view of a seal of the header box according to the second embodiment,

FIG. 9b is a partial sectional view showing an end of a tube of the heat exchanger according to the second embodiment assembled to the header box before compression of the seal of FIG. 9a;

FIG. 10a is a perspective view of a lower face of an inner plate of the header box according to the second embodiment,

FIG. 10b is a perspective view of a portion of an upper face of the inner plate of the header box according to the second embodiment,

FIG. 11a is a perspective view showing ends of tubes of the heat exchanger opening into a collecting box according to a third embodiment,

FIG. 1b is a sectional view of FIG.

FIG. 12a is a perspective view showing ends of tubes of the heat exchanger opening into a collecting box according to a fourth embodiment,

FIG. 12b is a sectional view of FIG. 12a, FIG. 13a is a view from above and in perspective of an internal plate of the collector box of FIGS. 12a and 12b, and

FIG. 13b is a view from below and in perspective of the inner plate of the collector box of FIGS. 12a and 12b,

FIG. 14a is a sectional view of a heat exchanger according to a fifth embodiment partially showing a heat exchange bundle comprising internal rings inserted into the ends of the tubes of the heat exchange bundle,

FIG. 14b is a sectional view schematically showing an inner ring inserted in one end of a tube of the heat exchange bundle, and

- Figure 14c shows schematically an inner ring of Figures 14a and 14b.

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

The following achievements are examples. Although the description refers to one or more embodiments, this does not necessarily mean that each reference relates to the same embodiment, or that the features apply only to a single embodiment. Simple features of 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.

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

As is partially illustrated in FIG. 1, a heat exchanger 1 conventionally comprises:

a heat exchange bundle comprising a plurality of tubes 11, arranged in one or more rows of tubes 11, and

- At least one manifold 20, generally two manifolds 20 (only one being visible in Figure 1), each manifold 20 comprising a header plate 21 through which the tubes 11, and a cover 23 intended to be fixed on the plate collector 21 to at least partially close the manifold 20.

The tubes 11 can extend longitudinally and be mounted between two manifolds 20, through the manifold plates 21 arranged transversely with respect to the tubes 11 and through which the ends of the tubes 11 pass through.

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 or each manifold 20 comprises a seal 25 (Figures 1 to 5, 7 to 9a and 11) or 25 '(Figures 13a to 14b). More specifically, it is a seal 25; 25 'compressible to be arranged at least partially on the collector plate 21 and around the ends of the tubes 11 opening into the manifold 20 to the assembly of the heat exchanger 1.

First embodiment

With reference to FIGS. 1 to 6b, a first embodiment of the heat exchanger 1 is described.

Heat exchange bundle

According to the first embodiment described, the heat exchange bundle 10 can be assembled by soldering, that is to say that the various elements are assembled together and then brazed by passing through a brazing furnace, to ensure the joining together of all the elements of the heat exchange bundle 10. For this purpose, the various elements of the heat exchange bundle 10 are metallic, preferably aluminum or aluminum alloy.

The heat exchange bundle 10 may further comprise tabs 13 (see FIGS. 1 to 5), for example of substantially undulating shape, separating the tubes 11 from each other, and intended to be traversed by a second fluid for an exchange. The spacers 13 are well known to those skilled in the art and are not described in greater detail herein.

The heat exchange bundle 10 may furthermore comprise two lateral flanges 15 on either side of the plurality of tubes 11, in this example on either side of the alternating stack of tubes 11 and dividers 13. The side cheeks 15 comprise respectively fixing means to the cover 23 of the manifold 20, for example mechanical, such as crimping tabs 151 configured to be folded on the cover 23 to the assembly of the heat exchange bundle 10 to the manifold 20.

In particular, according to this first embodiment, the tubes 11 of the heat exchange bundle are made from a metal sheet. The sealing of each tube 11 can be provided by soldering. For example the tubes 11 are formed by folding, so-called "folded tube" (see Figure 6a), or they can be stapled (see Figure 6b) or it can be electro-welded tubes.

According to the exemplary embodiments illustrated in Figures 1, 2 and 4 to 6a, 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. In other words, in this example the end of the bent tube 11 has two half-sections separated by the leg 113. By way of example, each tube 11 may have a substantially "B" cross section. Of course, any other type of folding can be provided. Alternatively, other sections may be provided, for example of substantially oblong shape defining a single channel 111 of fluid circulation, as shown in the example of Figure 6b.

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

To do this, the tubes 11 are mechanically assembled to each manifold 20. In a detailed manner, the tubes 11 are assembled to the manifold 20 so as to pass through the manifold plate 21, as is best seen in FIGS. 1 and 3 The ends of the tubes 11 opening into this manifold 20 are then plastically deformed. According to the embodiment described, this mechanical assembly is done 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 against the seal 25.

The flaring of the ends of tubes 11 is for example made by punching these ends.

Preferably, the flaring is carried out in a localized manner, that is to say that the flaring is not performed on 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. In particular in the case of 11 bent tubes for example in "B" having a substantially oblong cross section with a partition 113 connecting the long opposite sides, the ends of the tubes 11 are flared at the long sides but not at the partition 113 separating the channels 111, as in the example of Figures 1, 2, 4 and 5. In this example with the partition 113 substantially in the center, there is no central flaring of the ends of the tubes 11. In this particular example, the ends of the tubes 11 comprise four local flares 115 arranged on the long sides on either side of the partition 113. These flares 115 give a substantially corrugated profile to the long sides of the ends of the tubes 11.

The flares 115 on the peripheries of the ends of the tubes 11 therefore form bearing areas on the seal 25. At the flare or flares 115, the width of the ends of the tubes 11 increases. The width of the ends of the tubes 11 means the dimension joining the two opposite large sides. By way of nonlimiting example, the width of one end of a tube 11 at the flares 115 may be of the order of 1.5 times to 2.5 times the width of the end of the tube 11 before expansion.

It is possible to flare at least locally the ends of the tubes 11, so as to define one or more flares 115 only on the periphery of the ends of the tubes 11, namely the side opening into the inner volume of the manifold 20 to the assembled state.

Alternatively, it is possible to flare the ends of the tubes 11 in at least two distinct transverse sections of the ends of the tubes 11, as can be seen in FIG. 3. In particular, the ends of the tubes 11 may have:

on the one hand one or more so-called external flares 115 on the periphery of the ends of the tubes 11 opening into the manifold box 20, that is to say on the outside of the heat exchange bundle 10, and

- On the other hand one or more other flares 117 said internal, made on the side of the remainder of the heat exchange bundle 10, the inner side of the heat exchange bundle 10.

The width of the ends of the tubes 11 at the level of the external flares 115 is greater than the width of the ends of the tubes 11 at the level of the internal flares 117.

The local flares 115, 117 make it possible to compress and hold in place the gasket 25 in order to guarantee the seal between the collector plate 21 and the tubes 11. In addition, the external flares 115 have a function of mechanical retention of the seal 25 ensuring the holding in place and the compression of the seal 25.

The heat exchanger 1 also advantageously comprises one or more locking members 29, described in more detail below, arranged at the end of one or more tubes 11 so as to maintain the flare (s) 115, and thus maintaining the compression of the seal 25. These locking members 29 are advantageously formed on an element of the heat exchanger 1.

Slip box Collector plate

With regard to the collector plate 21, reference is made more particularly to FIG. 3. A plurality of openings 211 are provided on the collector plate 21 for the passage of the ends of the tubes 11 of the heat exchange bundle 10. The shape these openings 211 is complementary to the shape of the ends of the tubes 11 before flaring. For example, the openings 211 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.

According to the illustrated embodiment, the manifold plate 21 further comprises fastening means 213 to the lid 23, for example mechanical, such as crimping tabs that can be folded down on the cover 23. By way of example, the collector plate 21 has a peripheral rim 215, for example folded, having these fastening means 213.

Furthermore, according to the illustrated embodiment, the header plate 21 has a bottom 217 in which are formed the openings 211 and relative to which the peripheral edge 215 is raised. The bottom 217 may have collars 218 to facilitate the insertion of the tubes 11. The collector plate 21 further comprises, according to the first embodiment illustrated, a peripheral groove 219 for receiving at least a portion of the seal 25 This peripheral groove 219 connects the bottom 217 and the peripheral rim.

215 elevated. Lid

The cover 23, meanwhile, is assembled on the header plate 21 and has a longitudinal main extension direction L substantially transverse to the longitudinal axis of the tubes 11 in the assembled state of the heat exchanger 1. The lid 23 shown in the illustrated example a substantially longitudinal shape with two long longitudinal opposite sides, two opposite small side sides, and a substantially arch form connecting the four sides.

The lid 23 may be made of plastic. In this case, it is the seal 25 which provides a tight connection between the cover 23 and the collector plate 21.

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 and 3). The term "cover foot", the lower portion of the cover 23 which is on the side of the heat exchange bundle 10 assembly. 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.

According to the first embodiment illustrated in FIGS. 1 to 5, the one or more locking members 29 for holding the flare (s) 115 are carried, and more precisely formed on the cover 23.

Indeed, according to this first embodiment, several locking members 29 are made in the form of tongues 30, each being integral with the cover 23. The tongues 30 extend towards the tubes 11. cover 23 on the rest of the heat exchanger 1, each tongue 30 is inserted at least partially inside a tube end 11. The tongues 30 are also called inserts.

In order not to disturb the flow of the first fluid between the manifold 20 and the tubes 11, each tab 30 is advantageously inserted only on a portion of one end of a tube 11 and not so as to extend over any the end of the tube 11.

According to the particular embodiment of heat exchange bundle 10 with tubes bent at "B", each tongue 30 may be inserted on a half-section of a tube end 11, 11; the two half-sections of the extremity being separated by the leg 113 of the tube 11. In particular, one can provide two tabs 30 inserted on one end of a tube 11, each being inserted on a half-section of this tube end 11. As before, each tongue 30 is advantageously inserted only on a portion of a half-section of one end of a tube 11 and not so as to extend over the entire half-section of the end of the tube 11.

In particular, the lid 23 may comprise one or more tie rods 31, 35 extending into the interior volume of the lid 23. Such tie rods 31, 35 bear the tongues 30. These tie rods 31, 35 are advantageously integral with the lid 23.

According to a first variant illustrated in FIGS. 1 to 3, the cover 23 comprises a predefined number, here two, longitudinally extending tie rods 31, that is to say extending in the longitudinal direction L of the cover 23. The longitudinal tie rods 31 extend according to the illustrated example over the entire length of the cover 23 by connecting the two small lateral sides of the cover 23.

According to this first variant, the tongues 30 extend respectively from a longitudinal tie rod 31 in a direction substantially perpendicular to the longitudinal axis of this rod 31 and towards the ends of the tubes 11. The tongues 30 therefore extend along an axis parallel to the longitudinal axis of the tubes 11.

In addition, with reference to FIG. 2, the longitudinal tie rods 31 can extend opposite the channels 111 of the "B" tubes, in a substantially eccentric manner, so that the tongues 30 are respectively inserted into a channel 111 of FIG. a tube end 11 on the side opposite the leg 113.

In addition, according to this first variant, it is possible to provide transverse reinforcements 33, respectively enabling a longitudinal tie 31 to be connected to a large longitudinal side of the cover 23. The number of such transverse reinforcements 33 is left to the discretion of the person skilled in the art. according to the constraints. The transverse reinforcements 33 may be arranged symmetrically or otherwise with respect to a longitudinal central axis L of the cover 23.

According to a second variant illustrated in FIGS. 4 and 5, the cover 23 comprises a predetermined number of tie rods 35 extending transversely in the interior volume of the lid 23. The transverse tie rods extend according to the illustrated example over the entire width of the cover 23 by connecting the two long longitudinal sides of the cover 23.

According to this second variant, the tongues 30 respectively extend from of a transverse tie rod in a direction substantially perpendicular to the longitudinal axis L of the lid 23 and towards the ends of the tubes 11. The tongues 30 therefore extend along an axis parallel to the longitudinal axis of the tubes 11.

According to the particular example illustrated, the tabs 30 extend from a transverse tie first substantially parallel to the longitudinal axis L of the cover 23 towards a small lateral side of the cover 23 and then substantially perpendicularly. to the longitudinal axis L of the cover 23 and towards the ends of the tubes 11. In other words, each tongue 30 has a first portion extending substantially parallel to the longitudinal axis L of the lid 23 and a second portion s' extending substantially perpendicular to the longitudinal axis L of the cover 23.

Tabs 30 may be provided on two transverse tie rods juxtaposed so as to form:

a first row of tongues 30, comprising one or more tongues 30, extending from a first transverse tie, and

a second row of tongues 30, comprising one or more tongues 30, extending from the second transverse tie rod.

To save space, the first part of the tongues 30 of the second row may extend opposite to the first part of the tongues 30 of the first row, as illustrated in FIGS. 4 and 5. According to one either of these variants (Figures 1 to 5), each tongue 30 has an end, intended to be inserted into the end of a tube 11, of complementary shape to the at least partially flared shape of the end of 11. In other words, the tabs 30 are of complementary shape to the shape of the flares 115 at the ends of the tubes 11.

In the illustrated example, the tabs 30, in particular their ends, have in cross section a substantially trapezoidal shape including a base from which extend two non-parallel sides. The sides of the tongues 30 are configured to fit against the flares 115 at the ends of the tubes 11 and thus to maintain the flares 115 in order to guarantee the compression of the gasket 25.

Of course, the tongues 30 do not extend over the entire length of the associated tube end 11. The ends of the tubes 11 having a substantially oblong shape in the examples described, the length of one end of a tube 11 is the dimension joining the two small opposite sides of this end. More particularly, in the case where a tongue 30 is inserted on a half-section of an end of a tube 11 delimited by the leg 113 of the tube 11, this tongue 30 does not extend over the entire half-section, that is to say, it does not extend over the entire half-length of the end of the tube 11 so as not to obstruct the channel 111 and not to prevent the flow of the first fluid.

Thus, the tabs 30 form spacer jumpers which maintain a constant spacing, here between the two long sides of the ends of the tubes 11, at the flares 115, without completely obstructing the ends of the tubes 11, so as not to interfere. the flow of the first fluid.

In addition, the tongues 30 may have a solid shape, not perforated.

The tabs 30 may be evenly distributed or not.

The tongues 30 are advantageously provided at strategic points, for example at the longitudinal ends of the cover 23 (see FIG. 5) so as to be inserted into the ends of the tubes 11 at the beginning and / or at the end of the heat exchange bundle 10. .

Seal

The seal 25 is for example made of elastomer such as an ethylene-propylene-diene monomer known under the acronym EPDM.

As best seen in FIG. 3, the seal 25 comprises according to the first embodiment:

a peripheral part 251 shaped to follow the periphery of the collecting plate 21 so as to seal between the cover 23 and the collecting plate 21, and

a plurality of inverted flanges 255, extending in the direction of the heat exchange bundle 10 in the assembled state of the heat exchanger 1, and delimiting openings 254 adapted to receive the ends of the tubes 11 at the assembly of the heat exchange bundle 10 to the manifold box 20.

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. 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. The inverted collars 255 extend in the direction opposite to the direction of insertion of the tubes 11 into the collector plate 21. Finally, 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 provides a flexible connection between the collector plate 21 and the tubes 11, this makes it possible to absorb the stresses of deformation related to the thermal expansion. The seal 25 further comprises in this example a base 257, from which the inverted flanges 255 extend. The base 257 connects the peripheral portion 251 to the inverted flanges 255.

Second embodiment

A second embodiment, illustrated in Figures 7 to 10b, differs in particular from the first embodiment in that the manifold 20 further comprises an inner plate 27 separate from the header plate 21 (Figure 8), and arranged at less in part against the seal 25 (Figs. 9a, 9b) so as to maintain the seal 25 around the ends of the tubes 11 in the assembled state of the heat exchanger 1. Thus, the seal of 25 is compressed between the ends of the heat exchange tubes 11 and the inner plate 27, in the assembled state of the heat exchanger 1.

Collector plate

According to the second embodiment illustrated, the manifold plate 21 (FIG. 8) is substantially flat and devoid of a collar, more specifically it comprises a substantially planar bottom 217 without a collar, on which the openings 211 are formed and with respect to which the Perimeter border 215 is elevated.

Seal

According to this second embodiment, the seal 25 (FIGS. 9a, 9b) comprises a plurality of standard collars 253 extending towards the cover 23 at the assembly of the manifold 20 opposite the collars. Inverted 255 and also delimiting the openings 254 for the passage of the tubes 11. These standard collars 253 are intended to be received in the inner plate 27 to the assembly of the manifold 20.

There are as many standard collars 253 as reversed flanges 255. The standard flanges 253 are made in the extension of the inverted collars 255. The standard flanges 253 and the inverted flanges 255 extend in a direction parallel to the longitudinal axis of the tubes 11 in the assembled state of the heat exchanger 1. 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 to plate collector 21. More specifically, the standard collars 253 extend in the same direction as the direction of the insertion 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, for example the standard flanges 253 have, in cross section, a substantially oblong shape before assembly of the manifold 20.

Finally, similar to the inverted collars, the standard collars 253 are flexible and adapt to the shape of the tubes 11 and the openings 211 of the collector plate 21. The standard collars 253 are intended to be compressed during the expansion of the ends 11. The tightness between the tubes 11 and the header plate 21 is ensured by this compression of the standard collars 253 around the ends of the tubes 11.

Internal plate

The inner plate 27, better visible in Figures 10a, 10b, is preferably made of plastic.

This plate 27 is called "inner plate" because of its arrangement in the interior volume of the manifold 20 defined between the header plate 21 and the cover 23.

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 flanges 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 exchanger thermal 1.

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

More precisely, it is the standard collars 253 protruding of the seal 25 which are compressed between the ends of the tubes 11 and the inner plate 27.

The inner plate 27 has a lower face 27a shown in FIG. 10a and an opposite upper face 27b, shown in Figure 10b. The lower face 27a is intended to be arranged facing the base 257 of the seal 25 and the upper face 27b opposite the cover 23, to the assembly of the manifold 20. Thus, the base 257 of the seal sealing 25 is interposed between the inner plate 27 (its lower face 27a) and the header plate 21. The inner plate 27 thus forms a collector plate-against cooperating with the header plate 21 to maintain the seal 25.

Advantageously, the inner plate 27 is arranged and in particular sized so as to fill the spaces between the ends of the tubes 11. According to the first embodiment, the inner plate 27 makes it possible to fill the spaces between the base 257 of the gasket. sealing 25 and the standard collars 253 of the seal 25. The inner plate 27 thus forms a sheet that occupies substantially all of the space between the protruding ends of the tubes 11 passing through the standard collars 253. In particular, the internal plate 27, more precisely its upper face 27b, is arranged closer to the ends of the tubes 11. In other words, the ends of the tubes 11 flanked by the standard collars 253 of the seal 25 do not exceed almost, that is, that is to say, exceed the height of the internal plate 27 by a height of less than 2 mm, or even exceed it at all. nt, in particular by limiting the formation of vortices or turbulence in the zone where the tubes 11 open into the manifold 20 in the assembled state of the heat exchanger 1. Moreover, as is better visible in FIG. 10b, the internal plate 27 is 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. According to a first variant embodiment, the inner plate 27 and the seal

25 are two separate rooms. According to a second variant embodiment, the inner plate 27 and the seal 25 may be made in one piece. It may be a single piece bi-material that is to say having two materials: a first part in a first material acting as a seal 25 as described above, and a second part in one second material acting as an inner plate 27 as previously described. Such a part 25, 27 is for example made by co-molding.

This second variant makes it possible to limit the number of parts while allowing the assembly of the heat exchanger 1 to be accelerated.

In this second embodiment, the cover 23 and the locking members 29 are made similarly to the first embodiment.

Third embodiment

FIGS. 11a and 11b illustrate a third embodiment that differs in particular from the second embodiment in that the inner plate 27 'is arranged to hold the gasket 25' compressed between the ends of the tubes 11 and the manifold plate 21 and no longer between the ends of the tubes 11 and the inner plate 27 in contrast to the second embodiment. In addition, according to this third embodiment, the locking members 29 are formed on the inner plate 27 '.

In this case, the seal 25 'is integrally arranged below the inner plate 27' with reference to the arrangement of the elements in Figs. 1a and 1b.

According to this second embodiment, the seal 25 'does not comprise standard flanges 253 passing through the inner plate 27'. On the other hand, the seal 25 'has reversed collars 255 similarly to the first embodiment.

The seal 25 'further comprises bearing zones 258 on which the flares 115 of the tubes 11 are supported after expansion to compress the seal 25'. In this third embodiment, the tubes 11 have a single flare 115 on the periphery of the ends of the tubes 11.

As regards the inner plate 27 ', according to this third embodiment, its surface facing the cover 23 in the assembled state of the manifold 20 is substantially smooth so as not to disturb the flow of the first fluid. The inner plate 27 'has a plurality of openings 271 flanked by flanges 275, as best seen in Figure 1b. The collars 275 may be continuous over the entire periphery of the openings 271 or conversely may be interrupted as shown in Figures 13a and 13b of the fourth embodiment, by one or more slots 277.

Referring again to FIGS. 11a and 11b, these collars 275 are arranged on the periphery of the ends of the tubes 11 and extend towards the inside of the tubes 11. After insertion of the tubes 11 through the collector plate 21 and the gasket 25 ', the inner plate 27' is arranged over the gasket 25 'and the collars 275 are inserted inside the ends of the tubes 11. In the case where the collars 275 are not not continuous, the slots 277 (visible in Figures 13a, 13b) are advantageously provided so as to be located in line with the partition 113 (visible Figure 11a) when the tubes 11 open into the manifold 20.

The collars 275 are intended to be plastically deformed in a manner complementary to the ends of the tubes 11, so as to maintain the flared ends of the tubes 11 bearing against the seal 25 'to compress it. These flanges 275 of the inner plate 27 'thus form locking members 29 to hold the gasket 25' compressed between each end of the tube 11 and the collector plate 21.

According to the example of FIG. 11b, the deformed flanges 275 of the inner plate 27 'do not extend beyond the flares 115. In other words, the flanges 275 are arranged only on the flares 115 of the ends of the tubes 11.

Fourth embodiment

The fourth embodiment illustrated in Figures 12a to 13b differs from the third embodiment in that the seal 25 'and the inner plate 27' are adapted for tube ends 11 with a double flare.

According to this fourth embodiment, the ends of the tubes 11 are flared in at least two distinct transverse sections. In particular, the ends of the tubes 11 may have:

on the one hand one or more so-called external flares 115 on the periphery of the ends of the tubes 11 opening into the manifold box 20, that is to say on the outside of the heat exchange bundle 10, and on the other hand one or more other flares 117 said internal, made on the side of the remainder of the heat exchange bundle 10, the inner side of the heat exchange bundle 10.

The internal flare (s) 117 squeeze the gasket 25 'against the manifold plate 21. According to the illustrated embodiment, an internal flare (117) is formed over the entire internal cross section of the end of the tube (11).

The outer flare (s) 115 squeeze the gasket 25 'against the inner plate 27'.

According to the examples illustrated in FIGS. 12a and 12b, the width of the ends of the tubes 11 at the level of the external flares 115 is greater than the width of the ends of the tubes 11 at the level of the internal flares 117. The width of the ends of the tubes 11 at the level of the internal flares 117. external flares 115 and width of the ends of the tubes 11 at the inner flares 117 are of course greater than the width of the ends of the tubes 11 before flaring. In this case, the seal 25 'around one end of a tube 11 has two bearing zones 258 and 259 respectively for each flare 115 and 117 of this tube end 11 (see Figure 12b).

The collars 275 of the inner plate 27 ', according to this fourth embodiment, arranged on the periphery of the ends of the tubes 11 extend beyond the outer flares 115 of the ends of the tubes 11 towards the inside of the tubes 11. In other words, the flanges 275 comprise a first portion 275a intended to be deformed during flaring of the periphery of the ends of the tubes 11, and a second portion 275b which extends beyond the flares 115 of the ends of the tubes 11. direction of the interior of the tubes 11 after expansion. According to the illustrated example, this second portion 275b of the collars 275 extends substantially parallel to the longitudinal axis of the tubes 11 in the assembled state of the heat exchanger 1.

According to the example described, the second portions 275b of the flanges 275 of the inner plate 27 'do not extend beyond the internal flares 117.

Similarly to the third embodiment, the locking members 29 are formed by the collars 275 arranged at the ends of the tubes 11 so as to maintain the outer flare (s) 115, and thus maintain the compression of the gasket 25 '.

The other features are identical to the third embodiment and are not described again.

Fifth embodiment

A fifth embodiment shown in FIGS. 14a to 14c differs from the first embodiment in that the locking members 29 are made by added reinforcing pieces, such as internal rings 40, at the ends of the tubes. 11.

The locking members 29 are no longer carried by the cover 23 as described in the first embodiment. Unlike the four embodiments previously described, the locking members 29 are no longer formed on an element already present in the heat exchanger 1 but are inserts which are therefore additional to the elements already present in the heat exchanger 1 .

Advantageously, the internal rings 40 are made of a metallic material such as aluminum or aluminum alloy, chosen so that the internal rings 40 have mechanical characteristics, in particular mechanical strength to withstand pressure stresses. , superior to those tubes 11 whose sealing is provided by brazing, such as tubes bent "B".

In particular, the internal rings 40 are chosen with a thickness of the order of 0.15mm to 0.30mm.

The inner rings 40 have a section at least substantially equal to that of the tubes 11 before flaring. According to the particular case of a double flaring of the tubes 11 as described previously with reference to the first embodiment with an internal flaring 117 and an external flaring 115 (see FIG. 3), the section of the internal rings 40 is advantageously chosen at least substantially equal to the section of Γ internal flare 117 of the tubes 11 (see Figure 14b). In other words, the outer perimeter of the internal rings 40 is substantially equal to the internal perimeter of the tubes 11 before flaring of the periphery of the ends of the tubes 11.

The internal rings 40 are intended to be inserted mechanically and force inside the ends of the tubes 11, in other words on the inner perimeter of the tubes 11. With reference to FIG. 14b, the internal rings 40 are moreover chosen with a height less than the height of the tube 11 between the periphery of the end of the tube 11 and

Internal flaring 117.

Moreover, these internal rings 40 can be inserted into the ends of the tubes 11 by punching.

Each inner ring 40 is thus mechanically assembled inside a tube end 11. This insertion of the internal rings 40 can be made before or during the flaring of the ends of the tubes 11, in particular to achieve the external flares 115 (see FIG. 3) at the periphery of the ends of the tubes 11.

Referring again to FIGS. 14a to 14c, the insertion of the internal rings 40 inside the ends of the tubes 11 causes an increase in the perimeter of the tubes 11.

When the ends of the tubes 11 are flared (the perimeter of the ends with their external flares being schematized by the hard dotted lines in FIG. 14a), the perimeter of the tubes 11 and rings 40 increases, for example of the order of 5% to 10%. % of the perimeter before flaring. This increase in the perimeter, or in other words the width of the ends of the tubes 11, allows the compression of the seal 25 between the tubes 11 and the collecting plate 21, in particular the collars 218 of the collecting plate 21 (see FIGS. 3).

After flaring, the inner rings 40 maintain flaring tubes 11, or in other words maintain a section equal to or greater than the section of the tubes before flaring.

The internal rings 40 (better visible in FIGS. 14b and 14c) provide mechanical reinforcement of the ends of the tubes 11 thus improving the resistance of the tubes

II to the pressure of the seal 25. In other words, the inner rings 40 provide a mechanical strength to the ends of the tubes 11, so that the latter do not close under the stresses exerted by the seal 25 to the Assembled state of the heat exchanger 1.

Furthermore, according to the particular embodiment of heat exchange bundle 10 with tubes folded at "B", an example of which is shown diagrammatically in FIG. 6a, two internal rings 40, as schematized in FIGS. 14b, 14c, are inserted on each end of tube 11 (Figure 6a), each on a half-section of the tube 11; the two half-sections being separated by the leg 113 of the tube 11. Finally, in order to facilitate the insertion of the internal rings 40 inside the ends of the tubes 11, the internal rings 40 may have a chamfer 41, shown diagrammatically in FIG. 14c, at least on the side inserted first into the tubes 11. In this case, we also speak of chamfer 41.

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; 25 'provides both a mechanical connection function between the brazed heat exchange bundle 10 and the manifold box 20, but also a sealing function of the manifold box 20 and between the tubes 11 and the collector package 21. In FIG. in addition, the inner plate 27; 27 'when present participates in the compression of the seal 25; 25 'to guarantee the seal between the collector plate 21 and the tubes 11.

Finally, the locking members 29 carried by the cover 23 or the inner plate 27 ', made in the form of tabs / inserts 30, collars 275, or internal rings 40, prevent the tubes from closing again pushed by the seal 25; 25 ', thereby guaranteeing the mechanical strength of the tubes 11 and thus the seal between the collector plate 21 and the tubes 11.

Claims

REVE DICATIONS

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

at least one manifold (20) having a header plate (21),

- a heat exchange bundle (10) comprising a plurality of tubes (11), the tubes (11) respectively comprising at least one end opening into the manifold (20) and having at least one flare (115), and

at least one compressible gasket (25, 25 ') arranged at least partially on the collector plate (21) and around the ends of the tubes (11) opening into the collector box (20),

characterized in that said exchanger (1) further comprises at least one locking member (29) arranged at least partially inside the end of at least one tube (11) and shaped to maintain one flaring ( 115) of the end of said tube (11) to compress the seal (25, 25 ').

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

the tubes (11) have in cross-section two half-sections separated by a partition (113), and in which

two locking members (29) are inserted on a tube end (11), so that each locking member (29) is inserted on a half-section of the tube (11).

3. Heat exchanger (1) according to one of claims 1 or 2, comprising a plurality of locking members (29) regularly distributed.

4. Heat exchanger (1) according to any one of claims 1 to 3, wherein said at least one locking member (29) is formed on a member (23; 27 ') of the heat exchanger (1).

The heat exchanger (1) according to claim 4, wherein:

the collecting box (20) further comprises a cover (23) assembled to the collecting plate (21) so as to close the collecting box (20), and in which

said at least one locking member (29) is in the form of a tongue (30) integrally formed with the cover (23) extending in the direction of the tubes (11) and inserted at least partially inside the a tube end (11).

6. Heat exchanger (1) according to the preceding claim, wherein: the cover (23) has at least one tie (31, 35) integral with the cover (23) and extending into the interior of the lid (23), and wherein

the tongue (30) extends from the at least one tie rod (31, 35) towards a tube end (11).

7. Heat exchanger (1) according to the preceding claim, wherein the cover (23) has a substantially longitudinal shape, and said at least one tie rod (31) extends in the longitudinal direction (L) of the cover (23) or transversely in the interior volume of the lid (23).

8. heat exchanger (1) according to any one of claims 5 to 7, wherein the tongue (30) has an end of complementary shape to the at least partially flared shape of the end of a tube (11), for example a substantially trapezoidal shape.

9. Heat exchanger (1) according to claim 4, wherein:

the collecting box (20) further comprises an internal plate (27 ') distinct from the collecting plate (21) and arranged at least partly against the seal (25'), so that the seal (25 ') is interposed between the header plate (21) and the inner plate (27'), and wherein

the inner plate (27 ') has a plurality of openings (271) flanked by flanges (275) forming a plurality of locking members (29), the flanges (275) extending towards the tubes (11). and being arranged on the periphery of the ends of the tubes

(11), so as to maintain the gasket (25 ') compressed between each tube end (11) and the collector plate (21).

10. Heat exchanger (1) according to any one of claims 1 to 3, wherein said at least one locking member (29) is an additional piece relative to the elements of the heat exchanger (1) and assembled on a tube end (11).

11. Heat exchanger (1) according to the preceding claim, wherein said at least one locking member (29) is mechanically assembled within a tube end (11).

12. Heat exchanger (1) according to the preceding claim, wherein said at least one locking member (29) is formed as an inner ring (40).

13. Heat exchanger (1) according to the preceding claim, wherein the inner ring (40) has an outer perimeter substantially equal to the inner perimeter of the end of a tube (11) before flaring.

14. Heat exchanger (1) according to one of claims 12 or 13, wherein the inner ring (40) has at least one chamfer (41) shaped to facilitate the insertion of the inner ring (40) to the inside a tube end (11).

15. Heat exchanger (1) according to any one of claims 10 to 14, wherein said at least one locking member (29) is made of a metallic material, such as aluminum or aluminum alloy.