EP2513586A1

EP2513586A1 - Heat exchanger

Info

Publication number: EP2513586A1
Application number: EP10787108A
Authority: EP
Inventors: Paul Garret; Eric Piniarski
Original assignee: Valeo Systemes Thermiques SAS
Current assignee: Valeo Systemes Thermiques SAS
Priority date: 2009-12-18
Filing date: 2010-12-02
Publication date: 2012-10-24
Anticipated expiration: 2030-12-02
Also published as: US9488417B2; FR2954481B1; JP2013514514A; WO2011073038A1; JP5856068B2; US20130146267A1; PL2513586T3; EP2513586B1; CN102782435A; FR2954481A1; CN102782435B

Abstract

The invention relates to a heat exchanger comprising fluid exchange and flow elements (2, 2', 3), at least one fluid-collecting box (11, 11') into which exchange elements (2, 2', 3) lead, and a casing (4) for housing the exchange elements (2, 2', 3). The exchanger is characterized in that it comprises a flange (5) for attaching the collecting box (11, 11') to the casing (4), the flange comprising a groove (G1) for attaching the casing (4) and a groove (G2) for attaching the collecting box (11), the grooves (G1, G2) comprising a common wall (19). Owing to the invention, a highly compact heat exchanger is produced.

Description

Heat exchanger

The invention relates to a heat exchanger. A heat exchanger, for example used in the automotive industry and more specifically in an internal combustion engine of a motor vehicle, comprises heat exchange elements and fluid flow in which heat exchanging fluids circulate. between them. The heat exchange elements may for example comprise tubes, plates, fins, flow disruptors, etc. Many structural configurations are possible. For example, the exchanger may comprise a bundle of tubes arranged parallel to each other on one or more parallel rows with one another, these tubes being arranged to carry a first fluid, while a second fluid flows between the tubes and exchange of heat with the first fluid. Many fluid associations can be envisaged, be they liquids and / or gases.

The exchanger comprises a housing for receiving the tubes, which comprises a plurality of walls forming the volume in which the tubes are received. It is generally open at both ends, so that the tubes can be connected to collection or fluid distribution boxes also called manifolds: an inlet manifold and an outlet manifold. The first fluid flows into the tubes from the inlet header to the outlet manifold. The second fluid flows around the tubes, from an inlet pipe to an outlet pipe, and exchanges heat with the first fluid.

The exchanger also generally comprises two tube holding plates, the fluid collecting boxes being mounted on the collector plates. The tubes pass through orifices in the collector plates and open into the fluid collecting boxes.

Generally, the collector plates are fixed to the housing and the manifolds are attached to the collector plates, for example by crimping. For this purpose, each collector plate comprises means for crimping an edge of the collector box with which it is associated. Such a mode of fixation the box is known for example from WO 2008/125309 or from EP 2,031,338 in which the collector plate is in two parts assembled mechanically. In some engines, there are congestion constraints in the environment in which the exchanger must be mounted; it is therefore necessary to manufacture exchangers respecting these constraints. These constraints may for example require the manufacture of relatively flat form heat exchangers. For this purpose, flattened tubes are provided but of sufficiently large section to offer the fluid a passage section adapted to the desired flow rate. Such tubes have a section of slender shape; typically, they may have a rectangular section of dimensions 100mm by 7mm. Furthermore, in applications where for example water, which is a good coolant circulates between the tubes, it is preferable that the distance between successive tubes is low, for example equal to 2 or 3mm or less.

It is therefore necessary to manufacture collector plates with elongated orifices separated by walls of small width, said width corresponding to the distance between the successive tubes. In this case, the walls separating the orifices have a very large slenderness, that is to say that they are very elongated in one direction but thin in the other two. This raises the question of how they are made. For the manufacture of collector plates, punching processes known as "with fine cutting" are known, making it possible, from a relatively thick plate, to produce inter-orifices walls thinner than the thickness of the plate; for example, one can form orifices 60mm long in a 4mm thick plate with inter-orifices walls of width approximately equal to 2.6mm. However, in terms of forming a header plate with holes 100mm long and inter-hole walls of 2mm, a punching process with fine cutting can not be implemented. It is therefore necessary to use a conventional stamping process; if necessary, the thickness of the plate must be less than the width of the inter-tube walls and, for the above case, it is recommended a plate of very small thickness between 0.8mm and 1mm. However, if the manifold must be crimped by the header plate, it must have sufficient strength to perform this function. We are therefore faced with a dilemma, because if we increase the thickness of the collector plate (taking it for example to 1.5 or 2mm) it becomes impossible to implement a stamping process classic. It thus seems difficult to predict a significant slenderness for the tubes since it is necessary to ensure a sufficient thickness for the collector plate. We can see that the question of the compactness of a heat exchanger is particularly restrictive, subject to many developments and source of various problems. This is why the invention aims to provide a more compact architecture for a heat exchanger. It is noted that the invention arose from the resolution of a particularly sensitive problem in the case of a collector plate with orifices of great slenderness; the invention is however not limited to this single application, the invention also providing advantages in its application to collector plates with slender orifices more reasonable.

Thus, the invention relates to a heat exchanger comprising fluid exchange and flow elements, at least one fluid collection box into which the exchange elements and a housing housing of the elements of the exchange, characterized in that it comprises a flange for fixing the header to the housing, the flange having a groove (G1) for fixing the housing (4) and a groove (G2) for fixing the manifold (11). ), the grooves (G1, G2) having a common wall (19).

The grooves can receive or accommodate the walls of the housing and the collector box. The use of such a fastening flange provided with two grooves with a common wall provides a great compactness to the exchanger. Indeed, the manifold and the casing are compactly attached to each other without being directly fixed to one another, which guarantees the robustness of the assembly and allows in particular a good transmission of constraints.

Preferably, the grooves are opposite, that is, they are oriented in opposite directions. More specifically, the exchanger extending generally along an axis which is preferably the overall flow axis of the fluids within it, each groove has a bottom wall substantially transverse to said direction and a transverse peripheral opening, the openings being turned in two opposite directions on the said direction. According to one embodiment, the exchanger comprises at least one collecting plate for holding the exchange elements.

According to one embodiment in this case, the header plate and the fixing flange are formed in the same room.

According to another embodiment in this case, the fixing flange and the collector plate are separate parts fixed to the housing independently of one another. In this way, the functions of holding tubes and holding the collecting box are decoupled: two separate parts fulfill these functions, these parts being fixed to the casing independently of one another, that is to say without transmission. direct effort between them. In particular, it is thus possible to provide a collector plate of small thickness (typically 0.8 mm) with orifices of great slenderness; it is thus possible to form tubes of slender section and therefore a flattened and compact heat exchanger. The function of holding the manifold is provided by the flange, independently. We thus obtain a heat exchanger all the more compact.

According to one embodiment, the fastening flange and / or the collector plate is fixed directly to the casing. The exchanger thus gains even more compactness.

According to one embodiment, the fastening flange and the collector plate are non-contacting with each other. Thus, it is even better to ensure the absence of direct transmission of forces between these two parts which are not only not fixed to one another but are without contact with each other.

According to one embodiment, the exchange elements comprising tubes in which flows a first fluid (for example a gas) in communication with the box and around which flows a second fluid (for example a liquid), the header plate performs a sealing function between the first fluid and the second fluid and the flange performs a sealing function to the first fluid with the outside of the exchanger.

According to one embodiment, the manifold and the flange are crimped to each other. According to one embodiment, the flange is brazed to the housing. Such a method of attachment is robust and inexpensive. According to one embodiment in this case, the casing comprises at least one positioning tab arranged to be housed in an orifice of the flange for holding the latter on the casing during soldering.

Preferably in this case, the orifice is formed in the bottom of the crankcase fixing groove.

According to one embodiment, the positioning tab is arranged to be crimped against the fixing wall for its retention in the orifice. According to one embodiment, the positioning tab is arranged to be deformable for its maintenance in the orifice.

According to one embodiment, the header plate is brazed to the housing. According to one embodiment, the header plate has a skirt with a surface along which it is brazed to the housing. Thus, the contact surface is important which ensures good brazing of parts.

Preferably, the pipes have a section of generally rectangular shape, preferably whose length to width ratio is greater than 5.

The invention is particularly applicable to an air-water heat exchanger for example a water cooler recirculated exhaust gas or a charge air cooler of a combustion engine internal combustion of a motor vehicle.

The invention will be better understood with the aid of the following description of the preferred embodiment of the exchanger of the invention, with reference to the accompanying drawing plates, in which: - Figure 1 shows a perspective view of a first embodiment of the exchanger of the invention, with fluid manifolds attached to its fixing flanges;

FIG. 2 represents a detail (from above) of FIG. 1;

- Figure 3 shows a perspective view and in section in the plane of its height and its length of the exchanger of Figure 1;

- Figure 4 shows a perspective view and in section in the plane of its length and its width of the exchanger of Figure 1, without manifold;

FIG. 5 represents a partially exploded perspective view of the exchanger of FIG. 1, without a collecting box;

FIG. 6 represents an end view, from below and in perspective of the exchanger of FIG. 1, without a collecting box;

- Figure 7 shows a sectional view of a corner of the exchanger of Figure 1;

- Figure 8 shows a perspective view and partially transparent of a corner of the exchanger of Figure 1;

- Figure 9 shows a perspective view and partially in transparency and in section of a corner of the exchanger of Figure 1;

- Figure 10 shows a perspective view, seen from below, of a corner of the manifold of the exchanger of Figure 1;

FIG. 11 represents a perspective view, from the inside, of a corner of the exchanger of FIG.

FIG. 12 is a perspective and sectional view in the plane of its length and its width of a second embodiment of the exchanger of the invention;

With reference to the figures and more particularly to FIGS. 1 to 6, a heat exchanger 1 according to a first embodiment comprises elements 2, 2 ', 3 of heat exchange, a casing 4 for receiving or housing these elements 2 , 2 ', 3, a manifold 11 of air inlet and a manifold 11' of air outlet. The housing 4 has orifices 6, 7 for connection to water flow lines 8, 9, in this case an inlet pipe 9 and an outlet pipe 8, connected to a water circuit in which the exchanger 1 is mounted. In the embodiment described, the different elements of the exchanger 1 are brazed to each other, except the boxes 11, 11 'which are crimped; such exchangers with their brazed or crimped elements are well known to those skilled in the art with respect to their general characteristics.

The exchanger 1 described is an exchanger called "air-water", that is to say an exchanger in which the fluids that exchange heat are air and water. This is for example a water cooler exhaust gas called "recirculated" an internal combustion engine of a motor vehicle or a charge air cooler of such an engine; the water is preferably water from the so-called "low temperature" cooling circuit of said engine; it is typically brine.

With reference to FIG. 1, the exchanger 1 is generally of parallelepipedal shape. By convention and to simplify its description, we define the direction L of the length of the exchanger 1, which is its largest dimension, and in the direction in which the fluids flow, the direction 1 of the width of the exchanger 1 and the direction h of its height (or thickness). Subsequently, we will confuse the direction of these dimensions with their value; in other words, L, 1 or h respectively denote indifferently the length, the width and the height of the exchanger 1 or the direction of the length, the direction of the width and the direction of the height of the exchanger 1. D ' elsewhere, in the figures, a Cartesian coordinate system (L, 1, h) is formed on the basis of these mutually perpendicular directions. In addition, the notions of external (or external) and internal (or internal) used in the description refer to relative positions of elements relative to the outside or inside of the exchanger 1.

With reference to FIG. 3, the exchange elements comprise airflow tubes 2 of flattened shape. Their large size (which is the overall direction of the flow of air within them) is parallel to the direction of the length L of the exchanger 1 and their section transversely to this length L is rectangular in shape; the rectangle whose section of each tube 2 has the shape has a dimension parallel to the width 1 of the exchanger 1 and a dimension parallel to the height h of the exchanger 1. Each tube 2 has a length substantially equal to the length L of the exchanger 1 and a width substantially equal to the width 1 of the exchanger 1; its dimension parallel to the height h of the exchanger 1 (it is its thickness) is less than the height of the exchanger 1 and in this case relatively small, which gives the tubes 2 their flattened shape. For example, the thickness of the tubes 2 can be equal to about 7 or 8 mm for each tube 2, the width 1 of the tubes 2 being equal to about 100 mm. Furthermore, the inter-tube spaces (that is to say the water flow channels 3) may for example be of dimension (parallel to the height h of the exchanger 1) less than 3 mm, for example substantially equal to 2mm. Thus, the exchanger 1 is compact. The tubes 2 are assembled parallel to each other, the set of tubes 2 forming a stack in the direction of the height h of the exchanger 1; we also speak of bundle of tubes; the dimension of the entire beam parallel to the height h of the exchanger 1 is substantially equal to the height h of the exchanger 1. The tubes 2 are assembled to each other, parallel to each other, and allow the air circulation within them, generally in the direction of the length L of the exchanger.

In the tubes 2 are mounted fins 2 'disturbance of the air flow to facilitate heat exchange between air and water through the walls of the tubes 2. These fins 2' are well known to the air a person skilled in the art and it is not necessary to describe them in detail; they are here of corrugated shape and their section has, in end view along the axis of the length L of the exchanger 1, a serpentine shape between the walls of each tube 2.

In the water flow channels 3 formed between the tubes 2 are mounted disrupters (not shown) of the water flow, this flow preferably being carried out countercurrently, that is to say in the opposite direction of the direction of flow of the air. The disrupters are in the form of plates which extend substantially over the entire lateral surface of the tubes 2 (referred to as the lateral surface of the surface of the tubes 2 defined by the dimensions parallel to the length L and to the width 1 of the exchanger 1) and throughout the space between successive tubes 2 to which they are brazed; disrupters are also provided between the end tubes 2 and the casing walls 4. The disrupters have a shape creating turbulence in the flow of water passing through them to promote heat exchange, in a known manner.

As mentioned above, the exchanger 1 comprises, at each of its ends (in the dimension of its length L), an air manifold 11, 11 '. On the right side (in Figure 1), it is the manifold 1 1 inlet air and, on the left side, the manifold 11 'air outlet. The ends of Air circulation tubes 2 are connected to the air collecting boxes 11, 11 ', the inner volume of the tubes 2 thus being in fluid communication with the interior volume of the manifolds 11, 11'; in other words, the tubes 2 open into the manifolds 1 1, 1 1 '. The manifolds 11, 11 'are connected to pipes of an air circuit in which the exchanger 1 is mounted. The air is introduced into the tubes 2 via the inlet manifold. 11 and is collected at the outlet of the tubes 2 by the air outlet manifold 11 '. The structure of the exchanger will be described in more detail at its connection with the input box 11. The description that is made also applies to the exchanger at its output box 11 '. The input boxes 1 1 and output 11 'are in this case similar and mounted symmetrically; of course, according to another embodiment, they may be different.

The exchanger 1 comprises at its end a header plate 10, the function of which is to hold the tubes 2 in position, to guide the flow of air between the interior volume of the header 1 1 and the tubes 2 and 2. prevent the flow of water to the interior of the header 11, while preventing air and water flows from confluing; in other words, the header plate 10 seals between air and water. The collector plate 10 is often referred to by those skilled in the art by the term collector 10 and will be designated as such thereafter. The collector 10 is fixed to the casing 4, in this case by brazing, at a peripheral edge surface. Specifically in this case, the collector 10 has a peripheral skirt 10a having a side surface along which the collector 10 is brazed to the housing 4; this allows a simpler positioning between these two parts before brazing but also a better maintenance of one to the other, since the contact surface (and therefore brazing) is greater than if the collector 10 was brazed along. of a slice.

The peripheral skirt 10a is formed by the edge of the collector 10 which is folded, in this case over its entire periphery. The skirt 10a therefore extends perpendicularly to the overall plane of the plate forming the collector 10, thus parallel to the direction of the length L of the exchanger 1. The skirt 10a can be folded in one direction (as in FIG. 3) or in the other (as on Figure 12), ie outward or inward of the exchanger 1, respectively; the folding side depends in particular on the size and the distance between the collector 10 and the fastening flange 5 described below. Referring to Figure 5, the collector 10 is in the form of a plate mounted transversely to the length L of the exchanger 1 to receive the ends of the tubes 2. The collector 10 is pierced with a plurality of orifices 12, each orifice 12 being associated with a tube 2. Each orifice 12 has a shape corresponding to the section of a tube 2 and is bordered by walls 13 or flanges 13 or flanges 13 for retaining the end of the tubes 2 and keeping them in position; the collars also fulfill a function of stiffening the collector 10. These collars 13 extend generally perpendicularly to the overall plane of the plate forming the collector 10, therefore parallel to the direction of the length L of the exchanger 1, the end 13 'projecting from these flanges 13 being directed towards the inside of the exchanger 1; thus, the collars 13 extend, from the collector 10, around the tubes 2, which they enclose the ends. The ends of the tubes 2 are slid into these collars 13, forming a slide to grip them; each collar 13 forms a contact surface with the surface of the end of the tube 2 associated therewith, allowing them to be soldered to one another. The tubes 2, thus soldered to the flanges 13 bordering the orifices 12 of the collector 10, are fixed in position. The ends of the tubes 2 are thus separated from each other by the collars 13, the separation spaces between the successive tubes 2 define the channels 3 of flow of the water flow. As the flanges 13 are brazed at the ends of the tubes 2 and fill transversely (with respect to the direction of the length L of the exchanger 1) all the space between them, these collars 13 prevent the water from flowing in the volume of the manifold 1 1; in addition, these collars 13 also prevent water from flowing into the tubes 2. This type of collector 10 is well known to those skilled in the art and it is not necessary to describe it in more detail.

The casing 4 comprises, in the embodiment shown, two walls 15, 16 being L-shaped. In other words, each wall 15, 16 has a cross section (with respect to the direction of the length L of the exchanger 1). in the form of L. Each wall 15, 16 is L-shaped by folding around an edge to form two flaps (15a, 15b), (16a, 16b) perpendicular to each other. The interest of walls 15, 16 in L is their simplicity of manufacture and storage in view of the manufacture of exchangers (the storage can be done by simply nesting the walls on each other).

More specifically, each wall 15, 16 here comprises a large flap 15a, 16a and a small flap 15b, 16b. The large flap 15a, 16a is in the form of a rectangular plate of dimensions substantially equal to the length L of the exchanger 1 and its width 1, while the small flap 15b, 16b is in the form of a plate rectangular dimension substantially equal to the length L of the exchanger 1 and its height h. The concepts of large and small flaps are introduced here to allow a separate designation of each of the flaps (15a, 15b), (16a, 16b) of each wall 15, 16.

The inlet ducts 9 and water outlet 8 in the exchanger 1 are here connected to the same face of the exchanger 1, in this case the small flap 16b of the second wall 16.

The walls 15, 16 of the casing 4 are fixed to one another around the exchange elements 2, 2 ', 3; in this case, they are brazed. For this purpose, each wall 15, 16 comprises, at the free end of its small flap 15b, 16b, a raised edge 15c, 16c, which is an edge 15c, 16c of attachment to the large flap 16a, 15a of the other wall 16, 15. This raised edge 15c, 16c extends perpendicularly to the small flap 15b, 16b, from a folding edge by which it is connected thereto. R crimping tabs are arranged to ensure the connection between the raised edges 15c, 16c and corresponding large flaps 16a, 15a. Brazing allows the joining of the surfaces in contact and held against each other.

Once the walls 15, 16 are fixed, the flaps (15a, 15b), (16a, 16b) of the L-shaped walls 15, 16 form the four lateral faces of the exchanger 1 (referred to as lateral faces with respect to the direction of its length L).

It is recalled here that, in the embodiment described, the collector 10 is fixed to the casing 4 by brazing. More specifically, the outer surface of its peripheral skirt 10a is brazed to the inner surface of the flaps (15a, 15b), (16a, 16b) of the walls 15, 16.

A particular characteristic of the walls 15, 16 will now be described with reference to FIG. 7. Close to the contact zone between the edge 15c, 16c of the small flap 15b, 16b of each wall 15, 16 and the large flap 16a, 15a of the other wall 16, 15, there is an area where there is a clearance with the rounded corner of the collector 10 ( these two diagonally opposite games on the exchanger 1 are designated by the same reference J). Due to the existence of these games J, there is a risk of water leakage at their level. This is the reason why each wall 15, 16 comprises, close to each of the free corners of its large flap 15a, 16a, a sealing portion P. Each sealing portion P is in the form of a portion protruding from the inner surface of the large flap 15a, 16a of the wall 15, 16, towards the tubes 2; this protruding portion P has the shape of a corner or a fin. Such projecting portion P may either be stamped on the wall 15, 16 after its manufacture, or may be directly formed during the manufacture of the wall 15, 16. After soldering the surfaces in contact, the seal is thus ensured. at this sealing portion P.

It is noted that the walls 15, 16 each comprise two enlargements E, respectively, in the direction of the height h of the exchanger 1, formed near each end of its large flap 15a, 16a. These enlargements E are here formed by stamping the wall 15, 16. They are provided because the dimensions of the collector 10 are larger, in the direction of the height h of the exchanger 1, the size of the small flaps 15b, 16b walls 15, 16 in L; it is therefore enlargements E (or embossed E) housing the collector 10. These embossed E have an additional advantage: insofar as they house the collectors 10 in the direction of the height h of the exchanger 1, they form a stop in the dimension of the length L of the exchanger 1; thus, they form axial retention means (in this direction L) of the collectors 10 and therefore of all the exchange elements 2, 2 'during brazing of all the elements of the exchanger 1. The exchanger 1 further comprises a flange 5 for fixing the manifold 11 to the casing 4. This flange 5 is attached to the casing 4. It is fixed (in this case by brazing) to the end of the casing 4, along from the periphery of the latter; it is therefore a peripheral flange 5, of generally rectangular shape, in this case formed of a single piece. It is fixed to the casing 4 independently of the collector 10 and is not fixed thereto; in other words, the exchanger 1 has no means for fixing the fastening flange 5 to the collector 10. The flange 5 has a longitudinal wall 17 (in the longitudinal direction L) which extends along its entire periphery; this inner longitudinal wall 17 is arranged to extend on the inner side of the walls 15a, 15b, 16a, 16b of the casing 4 and be brazed to them.

The inner longitudinal wall 17 is folded outwards and in the direction of the exchanger 1, thus forming an inner transverse wall 18 and an intermediate longitudinal wall 19 forming with the inner longitudinal wall 17 a peripheral groove G 1 for accommodating the walls 15 a , 15b, 16a, 16b of the casing 4, thereby filling a function of fixing the housing 4. The inner transverse wall 18 forms a stop for the end of the walls 15a, 15b, 16a, 16b of the casing 4. The longitudinal wall intermediate 19 is folded outwards and in the reverse direction of the fold forming the peripheral groove G 1, thereby forming an outer transverse wall 20 and an outer longitudinal wall 21 forming with the intermediate longitudinal wall 19 a peripheral groove G 2 for housing a flange l ia of the end of the manifold January 1, thereby filling a function of fixing the manifold January 1; it is the end of the box 1 1 by which it is fixed to the flange 5; the rim l ia of the box 11 will be called fixing flange l ia.

Thus, the flange comprises two peripheral grooves G1, G2 formed by walls 17, 18, 19, 20, 21 of the fixing flange 5, these grooves G1, G2 having a common wall 19. Each groove G1, G2 is provided for the maintenance of a part, in this case for the maintenance of the housing 4 and the collector 1 1, respectively. More specifically, the housing 4 and the manifold 11 are each arranged so that their longitudinal end walls (along the length L of the exchanger 1) are inserted longitudinally in a peripheral groove G1, G2, by the transverse opening of this groove G1, G2. The grooves G1, G2 are oriented in opposite directions, that is to say that their openings are turned in two opposite directions along the direction of the length L of the exchanger 1. Because of their conformation with a common wall 19, they offer the exchanger 1 a great compactness and a good quality of maintaining parts 4, 1 1, either for brazing (for the housing 4) or for crimping (for the collector box) 1 1). In the extension of the outer longitudinal wall 21, the flange 5 comprises tabs 22 crimping the box 11 to the flange 5. These lugs 22 are arranged to be bent (folded) on the fixing flange 11a. The crimping tabs 22 are shown folded (that is to say in crimping position) on all of the figures. The box 11 is then crimped to the fastening flange 5.

With reference in particular to FIG. 4, the exchanger 1 is in this case arranged so that the collector 10 is fixed to the casing 4 at a distance d from the flange 5 and more precisely from the free end 17a of its longitudinal wall. internal 17.

Maintaining the tubes 2 is provided by the manifold 10 and the holding of the header 1 1 is ensured (by crimping) by the flange 5 itself brazed to the casing 4, the manifold 10 and the flange 5 being both brazed to casing 4 but independently of one another; in this case, they are even without contact with each other. Thus, the forces to which the flange 5 is subjected because of its function of holding the manifold 11 are not transmitted directly to the collector 11 which is connected to the casing 4 and to the tubes 2. the flange 5 are not transmitted to the collector January 1, the latter may be formed so as to receive tubes 2 slender section and separated from each other by a small distance. In particular, it is possible to form the collector 11 by a traditional stamping process on a thin plate; in such a method, the collars 13 of the collector 11 are stamped then their bottom is punched to form the orifices, in a known manner. By way of example, the plate making it possible to form the collector 10 having a thickness of approximately 1 mm, it is possible to form a collector 10 with orifices 12 of 100 mm by 7 or 8 mm approximately, with a inter-tube space of 2 to 3 mm. . The collars 13 may have a bulk (dimension parallel to the direction of the length L of the exchanger 1) substantially equal to 4mm; thus, by subtracting the thickness of the straps 14 (1mm), the collars 13 have a useful surface of contention of the end of the tubes 2 and brazing with them of about 3mm. In addition, the collector 10 being brazed directly to the casing 4, the radius of its corners is relatively large and the collector 10 is simpler to manufacture, this which is interesting because, because of the thickness of the collector 10, it is not always easy to conform it correctly.

A further advantage is that industrially, the implementation of the invention can be done with collectors of the prior art, thin but weak, by simply adding a clamp 5.

In the internal transverse wall 18 of the flange 5 (that is to say in the bottom of the groove G1) are provided orifices 23 for receiving locating lugs 24 protruding longitudinally out of the flaps 15a, 15b, 16a, 16b of the housing 4. Each tab 24 extends in the extension of the flap 15a, 15b, 16a, 16b which supports it; a flap 15a, 15b, 16a, 16b may comprise one or more lugs 24; all the flaps 15a, 15b, 16a, 16b or only a few may comprise one or more tabs 24. In this case, the exchanger 1 comprises a positioning tab 24 located in the middle of the end of each small flap 15a , 16a of the casing 4 and two positioning tabs 24 located at the end of each large flap 15b, 16b of the casing 4.

The positioning tabs 24 are arranged to be folded or deformed to maintain the flange 5 in position relative to the casing 4 by crimping. Their deformation also serves to guarantee their perfect soldering to the inner surfaces of the orifices 23 in which they are inserted, in order to fill the mounting clearance with these surfaces and to avoid any air leakage at this level, in other words to guarantee the tightness 23. For this purpose, the tabs 24 may be folded against the inner transverse wall 18, for example by bearing on the latter itself abutting on the end edge of the flaps 15a, 15b, 16a, 16b of the 4. They can also simply be deformed rather than crimped, insofar as a simple deformation would prevent them from moving relative to the flange 5.

The function of these tabs 24 is to allow the positioning and maintenance of the flange 5 on the casing 4 during the manufacture of the exchanger 1 and in particular before and during the brazing of its various constituent elements. Thus, the manufacture of the exchanger 1 is facilitated. The tubes 2 are stacked and inserted into the orifices of the collectors 10 and the walls 15, 16 L of the casing 4 attached around them and held in position relative to each other. the other thanks to the crimping tabs R; it may be noted here that other holding means such as clinching means could be provided. The flanges 5 are attached to the ends of the casing 4, the positioning tabs 24 being inserted into the holes 23 provided for this purpose and deformed, folded or crimped to maintain the assembly. The whole can then be brazed and is for this purpose arranged in an oven, in a known manner. The surfaces intended to be soldered to the casing 4 (and in particular the outer surfaces of the skirts 10a of the collectors 10 and the surfaces of the grooves G1) have substantial dimensions, which allows quality soldering, the contact surfaces being important. The inlet manifolds 1 1 and outlet 1 1 'can then be crimped to the exchanger 1, in this case by arranging with a seal 27 in the bottom of the groove G2 receiving the flange l ia of the box 1 1, in a known manner; it is an O-ring 27 diagrammatically shown in FIGS. 3 and 9.

Figures 3, 5, 6 and 8 to 1 1 show a particular characteristic of the exchanger 1: the corners of the flange 5 comprise a recessed portion 25 at the internal groove G1. Such a recessed portion 25 is provided to facilitate the manufacture of the flange 5 and promote the quality of its brazing on the casing 4, ensuring a sufficient brazing surface including in the corners. Indeed, the flange 5 is in this case formed by stamping and it is difficult to bend the material in the corners, as is known. Thus, thanks to the recessed portions 25, the amount of material in the corners is less important which allows them to be stamped so as to form an inner longitudinal wall which has, including in the corners, a sufficient length for soldering the housing 4 of quality.

Of course, the shape of the housing and more particularly the shape of the corners of the ends of the housing 4 is adapted to the shape of the flange 5, as seen for example in Figure 5 (the ends of the housing 4 being intended to come into stop in the internal groove G1 of the flange 5).

The manifold 1 1 comprises, at each corner, a bulge 26 corresponding to the recessed portion 25 of the flange 5. This bulge 26 is housed in the recessed portion 25, providing a holding function in position sealing gasket 27; indeed, the seal 27 would not be contained in the corners because of the recessed portions 25 of the flange 5.

FIG. 12 shows a second embodiment of the flange 5 of the exchanger 1. Its description will be brief and the references used for the previous embodiment will be retained, only the differences between these embodiments being described.

In the second embodiment shown in FIG. 12, the shape of the skirt 10a of the collector 10 is slightly different: it can be seen that it is not folded towards the manifold 11 as was the case in the first embodiment. embodiment but is folded on the other side, towards the other end of the exchanger 1. In any event, the collector 10 has an outer surface of peripheral skirt at which it is brazed to the inner surface of the housing walls 4, in this case at a distance d from the free end 17a of the inner longitudinal wall 17 of the flange 5.

The operation of the exchanger 1 (whatever its embodiment) is as follows (it is described briefly because well known to those skilled in the art). Air is supplied at the level of the air intake box 1 1, flows into the tubes 2 (this flow being disturbed by the fins 2 ') and leaves the exchanger 1 through the outlet box of air 1 1 '. Furthermore, the exchanger is supplied with water through the water inlet pipe 9, circulates in the water flow channels 3 (this circulation being disturbed by the disturbers) and leaves the exchanger 1 by the pipe 8 of water outlet. The air and water flows are against the direction in the direction of the length L of the exchanger 1; we speak of heat exchanger "against the current"; the efficiency of such an exchanger 1 is very good. The heat exchanger 1 has been described in relation to the air circulating in its tubes 2 and the water flowing between the tubes through the disrupters. It goes without saying that this could be reversed, that is to say water in the tubes and air between the tubes. Moreover, it could be air in both cases or water in both cases, or other fluids.

The invention has been described in connection with preferred embodiments, but it goes without saying that other embodiments can be envisaged. In particular, the characteristics of the various embodiments described can be combined with one another, if there are no incompatibilities.

Claims

claims

1-heat exchanger comprising elements (2, 2 ', 3) for exchange and fluid flow, at least one fluid collecting box (1 1, 1 1') into which the exchange elements ( 2, 2 ', 3) and a housing (4) housing the exchange elements (2, 2', 3), characterized in that it comprises a flange (5) for fixing the manifold (11 , 1 1 ') to the housing (4), the flange having a groove (G1) for fixing the housing (4) and a groove (G2) for fixing the manifold (1 1), the grooves (G1, G2) having a common wall (19).

2- exchanger according to claim 1 comprising at least one plate (10) for holding the exchange elements (2, 2 ', 3 ").

3- exchanger according to claim 2 wherein the fixing flange (5) and the collector plate (10) are separate parts fixed to the housing (4) independently of one another.

4- exchanger according to claim 3 wherein the fastening flange (5) and the collector plate (10) are without contact with each other.

5- exchanger according to one of claims 2 to 4 wherein the fixing flange (5) and / or the header plate (10) is fixed directly to the housing (4).

6- exchanger according to one of claims 1 to 5 wherein the manifold (1 1, 11 ') and the flange (5) are crimped to each other.

7- exchanger according to one of claims 1 to 6, wherein the flange (5) is brazed to the housing (4) and the housing (4) has at least one tab (24) positioning arranged to be housed in a hole (23) of the flange (5) for the maintenance of the latter on the housing (4) during their brazing.

8- exchanger according to claim 7 wherein the orifice (23) is formed in the bottom of the groove (G1) fixing the housing. 9-exchanger according to one of claims 2 to 8, claims 3 to

6 to be taken in their connection to claim 2, in which the collector plate (10) has a skirt (10a) with a surface along which it is soldered to the housing (4).