LU500978B1

LU500978B1 - Heat exchanger and method for assembling and operating the same

Info

Publication number: LU500978B1
Application number: LU500978A
Authority: LU
Inventors: Christian Cantor; Victor Caudy; Thierry Berger
Original assignee: Estra Automotive Systems Luxembourg S A R L
Priority date: 2021-12-10
Filing date: 2021-12-10
Publication date: 2023-06-12

Abstract

A heat exchanger (10) for an automotive application comprising: a plurality of flat tubes (12) for conveying a coolant fluid, wherein the flat tubes (12) extend in a first direction (Y); a first tank (14) extending over a tank length along a second direction (Z) and to which said flat tubes (12) are fluidly connected, wherein the tank (14) comprises a body (16) having a cavity (18) for said coolant fluid, a tank opening (20) of said cavity (18) being delimited by a peripheral border (22) of said tank body (16); a header plate (24) closing said tank opening (20), said header plate (24) having a rear side (26) facing the cavity (18), and an opposite front side (28), wherein the header plate (24) comprises oblong through-holes (30) receiving end portions (12.1) of the flat tubes (12);characterized in that the heat exchanger (10) further comprises: a plurality of mounting members (32), each mounting member (32) comprising an oblong aperture (34) which receives a first end portion (12.1) of a respective tube (12), wherein each mounting member (32) is fixedly attached on the header plate (24) at a position where the corresponding first end portion (12.1) of the respective tube (12) engages in a respective through-hole (30) of the header plate (24); wherein each mounting member (32) is attached to said corresponding first end portion (12.1) by brazing; at least a flexible first sealing means (36) configured to surround at least one first end portion (12.1) of a respective tube of the plurality of tubes (12), wherein the first sealing means (36) extends between the front side (28) of the header plate (24) and the respective mounting member (32), whereby the first sealing means (36) movably supports the respective first end portion (12.1) of the tube (12) in respect to the header plate (24).

Description

1 LUS00978

Heat exchanger and method for assembling and operating the same

FIELD OF THE INVENTION

The present invention generally relates to the field of heat exchangers and particularly relates to fluid-air heat exchangers as arranged in automotive vehicles.

BACKGROUND OF THE INVENTION

A heat exchanger such as a radiator, condenser or evaporator, for use in an automotive vehicle, includes usually an inlet tank, an outlet tank and a plurality of flat tubes extending between the tanks. The tubes connect fluidly the two tanks and enable a fluid flow between them. The connection of the tubes to a tank is established by means of a respective header plate comprising oblong apertures in which the tubes are fitted, and which closes the tank cavity. Commonly, a circumferential seal is arranged between the header plate and the tank opening, which is also referred to as peripheral portion or "tank foot". In this arrangement, the seal, which provide a fluid-tight mounting, is compressed between the tank and the header plate. According to prior art, header plates and tubes are typically assembled into a unitary structure and brazed and then assembled with the plastic tanks.

Further according to the prior art, some heat exchanger arrangements require a single seal on the header plate, wherein the seal extends partially into the openings of the header plate, such that when the tubes are received by openings, portions of the seal extend between each tube and wall portions of the header plate defining the opening.

For example, WO 2018/060622 A1 describes a heat exchanger comprising a collector plate comprising holes into which ends of tubes are inserted, wherein the collector plate comprises a compressible seal forming compressible flanges, the flanges being inserted into the holes and compressed between the wall of the holes and the ends of the tubes in order to provide the seal between said ends of the tubes and the collector plate.

2 LUS00978

Other prior art heat exchangers provide a brazed joint between the tube end section entering the opening of the header plate, which provides a rather rigid and robust sealing solution.

A known issue with such arrangements is the thermal cycle resistance. Indeed, during operation, the tubes are subjected to thermally induced mechanical stresses of different intensity, which depend on a temperature gradient vastly reliant on the temperature of the coolant flowing through the tube and the exterior environment. The temperature gradient may differ significantly from tube to tube and may also be dependent on other parameter such as e.g. a number of heating cycles, a running time of the heat exchanger and/or a geometry of one or more adjacent heat emitting devices, such as, e.g. an electrical battery or an engine.

As a consequence, each tube is subjected to thermal expansion which induce forces, respectively stress, to the central body. In their sum, these forces acting on the tubes, and in particular on the brazing junctions where the tubes are connected to the header plate, represent a load which regularly leads to leakages and/or shorten the service life of the heat exchanger.

OBJECT OF THE INVENTION

The object of the present invention is to provide an improved heat exchanger having an enhanced service life, wherein the heat exchanger is provided with an enhanced thermal cycle resistance and the possibility to compensate stresses.

This object is achieved by a heat exchanger as claimed in the independent claim.

SUMMARY OF THE INVENTION

According to the invention, a heat exchanger for an automotive application comprises: a plurality of flat tubes for conveying a coolant fluid, wherein the flat tubes extend in a first direction. The heat exchanger comprises further a first tank extending over a tank length along a second direction and to which said flat tubes are fluidly connected, wherein the tank comprises a body having a cavity for said coolant fluid. The tank includes an interface wall having a rear side facing the cavity, and an opposite front side, wherein the interface wall comprises oblong through-holes receiving end portions of the flat tubes. The heat exchanger further

3 LUS00978 comprises a plurality of mounting members, each mounting member comprising at least one oblong aperture which receives a first end portion of a respective tube, wherein each mounting member is fixedly attached on the tank and/or interface wall at a position where the corresponding first end portion of the respective tube engages in a respective through-hole of the interface wall, wherein each mounting member is sealably attached to said corresponding first end portion. The heat exchanger further comprises flexible first sealing means configured to surround at least one first end portion of a tube of the plurality of tubes wherein the first sealing means extends between the front side of the header plate and the respective mounting member, whereby the first sealing means movably supports, in a fluid tight manner, the respective first end portion of the tube with respect to the interface wall.

As will be noted, the respective tubes are attached in a sealed manner to the mounting member. Typically, the oblong aperture in the mounting member is dimensioned so that it contacts the respective tube end around its periphery, optionally by way of a collar to increase the contact surface. A fluid-tight attachment of the tube end to the mounting member in the through hole can be obtained by metallurgical binding, e.g. by brazing, welding, laser welding or similar, or by any other means, e.g. gluing or the like. "Sealing means" generally refers to a sealing element or device, wherein the sealing means is (configured to) surround, respectively encompass and/or enclose or seal the end portion of a tube against another element, such as for example the interface wall and/or the mounting member. "Sealably attached" refers to a liquid tight arrangement comprising elements that are fixedly attached to one another. "Interface wall" generally refers to a closing, wall-like structure, such as for example a closure panel or partition. The interface wall can generally be integral with the tank. Alternatively, the interface wall consists of or comprise a header plate, which is a separated element for closing the tank, wherein the header plate is fixedly attached to the tank.

4 LUS00978

In this context, it should be further noted that the brazing is done in a manner so as to provide a gas- and/or liquid tight junction between the header plate and the corresponding tube.

It shall be appreciated that the heat exchanger according to the invention generally provides a flexible connection between each tube and the tank, respectively the manifold. In particular, a free expansion of the tube versus the tubes asides is permitted, which permits the individual tubes to resist to thermal cycle issues due to different temperature gradient(s) in heat exchanger core. In particular the soft, respectively flexible, sealing means allows to provide a high degree of flexibility to a dilatating, corresponding tube. It is thus possible to compensate for mechanical stresses induced by thermal dilatations of the tubes.

It had been further found by the inventors that the proposed heat exchanger may be assembled particularly economical and easily, since the tubes may be brazed to their respective mounting members. It is for example possible to assemble the heat exchanger directly at a customer's premises or assembly lines, if required.

It had been further found by the inventors that the proposed heat exchanger may also be used to cool down a so-called U-flow battery cooling tube. In this context, it should be noted that since the tubes are brazed to the mounting plates, a further brazing between the mounting plates and a respective tank body is not required.

As a consequence, the proposed heat exchanger provides a possibility to simply clinch the tubes brazed to the mounting elements on a respective tank body and/or header plate. This in turn leads to a reduced production time and costs.

The tank may have any appropriate design with an interface wall having oblong through holes. In embodiments, the tank comprises a tank opening of the cavity delimited by a peripheral border of the tank body, and the interface wall is formed by a header plate closing said tank opening. This is a conventional design where the tank may be made of plastic and the header plate, with the oblong through holes, is made of metal, e.g. aluminum alloy.

In some embodiments, the tank body and the interface wall are integrally formed. "Integrally formed" refers to a configuration wherein the interface wall or a header plate forming (part of) the interface wall are formed integral with the tank body,

5 LUS00978 and/or wherein the interface wall and the tank body are permanently bonded to each other. In general, such an arrangement can be manufactured particularly quickly in an assembly line, as the intermediate step of attaching the interface wall and/or the header plate to the tank body is eliminated. Such an integral tank is commonly referred to as manifold. It may be formed by e.g. metal extrusion as a tubular member with a relatively flattened wall portion, subsequently provided with the oblong apertures, thus forming an integral interface wall.

In embodiments, each mounting member has two lateral fixing arms bended over the peripheral border of the tank body and/or a fixing tab of the interface wall. The lateral fixing arms allow a stable and quick connection between the mounting elements and the interface wall and/or the tank body. "Fixing tab" generally refers to a peripheral edge of the interface wall (or header plate).

In embodiments, the first sealing means comprises a plurality of separate/independent sealing elements, one per tube, wherein each sealing element comprises a single hole and hence individually surrounds and seals one corresponding respective first end portion. According to this embodiment, the sealing elements, may e.g. take the form of sealing rings or the like. In general, the first sealing means seals the tube end portion against the mounting member as well as the interface wall or header plate. Here, one sealing element is provided by tube, thus with a single hole to accommodate and seal a single tube end.

In alternatives, the first sealing means may comprise a gasket member (or gasket frame) comprising a plurality of holes to receive therein a plurality of tube ends.

The gasket member may comprise a number of holes corresponding to the number or through holes in the interface wall, or a part thereof (however more than 1 hole, preferably more than 5 holes).

The holes of the first sealing means are dimensions in consideration of the tube ends: they provide an opening in the sealing means that tightly surrounds the tube end.

6 LUS00978

In some embodiments, the heat exchanger comprises further a second sealing means, wherein the second sealing means is arranged on the peripheral border between the rear side of the interface wall and the tank body. In other words, the second sealing means may be arranged on the peripheral border of the tank body between the read (rear) side of the header plate or the interface wall and the tank body. In general, the second sealing means allows an improved seal between the header plate and the tank body. Depending on the configuration and geometry of the second sealing means, the sealing means may also seal against the end portion of a tube.

In some embodiments, the heat exchanger further comprises a second tank arranged adjacent to the first tank, wherein the second tank is identical or similar in construction to the first tank, wherein the interface wall of the second tank comprises oblong through-holes receiving first end portions of corresponding tubes, wherein the first end portions are directly attached to the header plate of the second tank by brazing.

In general, such an arrangement allows that several tanks, respectively manifolds are spaced adjacently to one another, wherein only one of the tanks is provided with mounting members brazed to corresponding tube ends, and wherein the other tank is directly brazed to its corresponding tube ends. As a consequence, this embodiment provides a heat exchanger that has several tanks, whereby the tubes attached to one tank may slightly move due to thermal deformations. This embodiment foresees that only those tubes of the plurality of tubes are connected by means of the mounting members to the tank body for which a greater deformation is to be expected due to a temperature gradient forming during the operating time of the heat exchanger.

In some embodiments, the first tank further comprises a first cap and a second cap, wherein the second tank further comprises a first cap and a second cap, and wherein the second cap of the first tank and the first cap of the second tank contact each other, such that the body of the first tank and the body of the second tank are separated from one another by the second cap of the first tank and the first cap of the second tank.

7 LUS00978

In some embodiments, the second cap comprises an inlet. "Inlet" refers to an opening or conduct which allows to conduct a medium, e.g. a coolant fluid or liquid, into the respective tank.

In some embodiments, the heat exchanger further comprises a supplementary tank extending over a tank length along the second direction and to which a plurality of second end portions of the plurality of tubes are fluidly connected, wherein the supplementary tank is arranged opposite to the first tank.

The supplementary tank may be identical or similar in construction to the first tank. Alternatively, the supplementary tank may have different dimensions and/or a greater volume. The supplementary tank is arranged opposite to the first tank and at the second end portion of each tube of the plurality of tubes. In general, the supplementary tank, as any other tank, may function as a manifold. The second end portions engaging in the supplementary tank, respectively the header plate of the supplementary tank may for example be brazed directly to the header plate of the second tank.

In some embodiments, the aperture of each mounting member is delimited by a collar element protruding from a chassis of the mounting member. The collar element improves the stability of the junction between the engaging tube end and the mounting member.

In some embodiments, the chassis comprises a first plate section and a second plate section arranged at an angle to each other. The angle inside the chassis makes the mounting member particularly quick and easy to use as a clip, meaning that clipping/clinching the mounting member to a header plate and/or tank body within a production setting is made easier and faster.

In some embodiments, at least the first tank consists of or comprises a polymer, in particular a polyamide, a polypropylene, a resin, a thermoplastic polymer, or mixtures thereof.

In some embodiments, each tube of the plurality of tubes comprises or consists of a solderable metal, wherein the metal comprises aluminum (elemental or alloy).

8 LUS00978

In some embodiments, the first sealing means consists of or comprises at least one of the following: a rubber, a polymer, a polymer-based material, an ethylene propylene diene monomer (rubber), or mixtures thereof.

In embodiments, the mounting member comprises a single oblong aperture, i.e. itis configured to receive a single tube end.

In embodiments, the mounting member comprises between two and five apertures, e.g. 2, 3, 4 or 5. adjacently arranged to each other along the second direction. In other words, a mounting member may be connected to one or more adjacent tube end portions arranged above each other along the tank length/height (second direction). This arrangement allows that the number of mounting members may be reduced whilst still providing a high degree of flexibility to tubes subjected to thermal stresses.

In some embodiments, the mounting member comprises two apertures (or more) arranged next to one another at the same level/height. In such case the mounting member receives two adjacently arranged tubes at same level. Here the tank may comprise two separate cavities, whereby the flow direction in the first cavity is different from the second cavity.

The invention is further related to a method for assembling a heat exchanger according to the invention. The method for assembling a heat exchanger according to the invention comprises: forming a plurality of mounting members, wherein forming the plurality of mounting members comprises (i) pre-stamping an integral mounting member assembly, and (ii) separating each mounting member from the pre-stamped mounting member assembly during a clinching step.

The features and advantages of the heat exchanger and the different embodiments of the heat exchanger do also apply for the method for assembling the heat exchanger according to the invention.

The invention is further related to a method for operating a heat exchanger according to the invention, wherein the method comprises: (i) conducting a coolant fluid stored within the second tank out of the second tank; and (ii) subsequently conducting said coolant fluid subsequently into the first tank.

The features and advantages of the heat exchanger and the different embodiments of the heat exchanger do also apply to the method for operating the heat exchanger according to the invention.

It should be noted that the present invention can generally be used for any configurations of a heat exchanger, be it for |-flow configuration (inlet and outlet tanks at opposite ends of the tubes) or U-flow configuration (inlet and outlet tanks on the same side). The present heat exchanger may generally be used as radiator in automotive vehicles or for cooling a battery device within a vehicle, however other applications are also possible.

BRIEF DESCRIBTION OF THE DRAWINGS

The present invention will now be described, by way of example, with reference to the accompanying drawings, in which:

Fig.1: is a principle exploded view of an embodiment of tank and pipe assembly used in the inventive heat exchanger;

Fig.2: is a principle view corresponding to Fig. 1 in an assembled state;

Fig.3: is an exploded view of a heat exchanger according to a further embodiment;

Fig.4: is an assembled view of the heat exchanger illustrated in Fig. 3;

Fig.5: is a view on a cutting-plane cutting perpendicularly along a height direction of the heat exchanger of Fig.4;

Fig.6: is a perspective view of a mounting member having a collar element;

Fig.7: is an exploded view of a heat exchanger according to a further embodiment;

Fig. 8: is a view of the heat exchanger of Fig. 7 in an assembled state;

Fig. 9: is a view on a cutting-plane cutting perpendicularly along a height direction of a heat exchanger according to a further embodiment;

Fig. 10: is a perspective view of a mounting member having an angled chassis;

Fig.11: is an exploded view of a heat exchanger according to a further embodiment;

Fig.12: is a view of the heat exchanger of Fig. 11 in an assembled state;

Fig.13: is a view on a cutting-plane cutting perpendicularly along a height direction of the heat exchanger according to Fig. 11 and 12;

Fig.14: is a perspective view of amounting member having two apertures, each having a collar element.

DETAILED DESCRIBTION OF PREFERRED EMBODIMENTS

Referring to Figs. 1 and 2, a heat exchanger 10 conventionally comprises a plurality of flat tubes 12 for conveying a coolant fluid, wherein the flat tubes 12 extend in a first direction Y. In automotive applications, the first direction often corresponds to a direction along a width of a vehicle.

In the present embodiment, the heat exchanger comprises a first tank 14 extending over a tank length along a second direction Z, which is perpendicular to the first direction Y. In the heat exchanger forms part in an automotive application, the second direction conventionally corresponds to a direction along the height of a vehicle. The tank 14 has a body 16 presenting a cavity 18 (as seen best in Fig. 3) for the coolant fluid. An opening of the cavity 18, which is also referred to as tank opening 20 (seen best in Fig. 3) is defined, respectively delimited by a peripheral border 22 of the tank body 16.

A plurality of flat tubes 12 is in fluid communication, respectively fluidly connected, to the tank body 16. It should be noted that Fig.1 and Fig.2 schematically illustrate partially a flat tube 12 and in particular the first end portion 12.1 of the flat tube 12. The second end portion of the tube 12 is not illustrated in Figs. 1 and 2.

A header plate 24 is provided for closing the tank opening 20, which then forms an interface wall for connecting the tubes. The header plate 24 comprises a rear side 26 which faces the cavity 18 as well as a front side 28 opposite of the rear side 26. The header plate 24 further comprises through holes 30, which have an oblong cross-section and extend transversally, generally perpendicularly to the

11 LUS00978 tank length (direction X). It is understood, that the through holes 30 as well as the flat tubes 12 may also have a different form in other embodiments. Any appropriate flat tube design may be used; however, the through-holes 30 are configured for receiving the end portions 12.1 of the tubes 12.

The heat exchanger 10 further comprises a plurality of elementary, respectively individual, mounting members 32. The mounting members 32 have likewise oblong through-holes, respectively apertures 34, for receiving corresponding first end portions 12.1 of a respective tube 12. It should be noted that the form of the aperture 34 is not limited to an oblong form. Each mounting member 32 is connected to a tube end portion 12.1 of a respective tube by brazing.

In general, the aperture 34 receives a first end portion 12.1 of a respective tube 12. Each mounting member 32 of the plurality of mounting members 32 is fixedly attached to the header plate 24 at a position where the corresponding first end portion 12.1 of the respective tube 12 engages in or protrudes into in a respective through-hole 30 of the header plate 24. In particular, the mounting member 32 may be clinched or clipped onto the header plate 24 and/or the tank body 16. In order to clinch the mounting member 32, the mounting member 32 has two peripheral, bendable fixing arms 38. As illustrated in Fig. 2, the fixing arms 38 are bended over the peripheral border 22 of the tank 16 as well as over the header plate 24.

In addition, each mounting member 32 is fixedly attached to a corresponding end portion 12.1 of a tube by brazing. Thereby, a very rigid junction is formed between the tube end portion of an individual tube and the mounting member 32, whereas a rigid junction between the end portion 12.1 of each tube 12 of a plurality of tubes and the header plate 28 can be omitted. In general, a brazed connection is also gas- and or liquid tight connection.

The heat exchanger 10 illustrated in Figs. 1 and 2 further comprises at least a flexible first sealing means 36 configured to surround, respectively encompass or seal, the end portion 12.1 of the tube 12. The sealing means 36 thereby seals the header plate 28 against the mounting member 32 as well as the end portion 12.1 of the tube. In this context, it should again be noted that Figs. 1 and 2 are purely

12 LUS00978 schematic. The first sealing means 36 is illustrated best in Fig 3, Fig. 5 or Fig. 7.

In this respect, Fig. 3 illustrates a first sealing means 36 comprising a gasket 36.1 formed of a plurality of sealing means connected to one another, whereas Fig. 7 illustrates a sealing means 36 comprising a plurality of sealing elements 36.2 that are separated from one another.

In general, the first sealing means 36 thus extends between the front side 28 of the header plate 24 and the mounting member 32, whereby the sealing means 36 supports the first end portion 12.1 in a fluid-tight and movable manner with respect to the header plate 24.

This is particularly useful during the assembly as well as during the operation of the heat exchanger 10. During the operation of the heat exchanger 10, the tubes 12 are subjected to thermally induced mechanical stresses and dilatations. In cases where the plurality of tubes 12 is directly brazed to the header plate, the dilatations and stresses are transferred to the header plate directly. This causes regularly high stresses on the side of the tank body whereon the through-holes are arranged. Thanks to the arrangement of a first sealing means 36 and a mounting member 32, the stresses caused by the thermal load subjected on an individual tube are transmitted to the mounting member 32 and compensated by the first sealing means 36. In this respect, is should be noted that the tube end portions 12.1 are brazed to the mounting members 32 (instead of brazing them to the header plate). In other words, the different dilatations of the different tubes 12 caused by different temperature gradients are compensated by the first sealing means 36 and the mounting member 32.

According to the embodiment illustrated in Fig. 1 and Fig. 2, the heat exchanger 10 further comprises a second sealing means 40. The second sealing means 40 is arranged between the peripheral border 22 of the tank body 16 and the header plate 24.

Fig. 3 and Fig. 4 illustrate a heat exchanger 10 according to an embodiment based on the schematic principle illustrated by Fig. 1 and Fig. 2. The heat exchanger 10 illustrated in Fig. 3 and Fig. 4 comprises a first tank 14, a header plate 24, a plurality of mounting members 32, a second sealing means 40. The

13 LUS00978 first sealing means is formed as a single gasket 36.1. Due to this arrangement, an assembly of the heat exchanger illustrated in Fig. 3 and Fig. 4 can be carried out particularly fast.

As can be further derived from Fig. 3 and Fig. 4, the heat exchanger 10 comprises afurther, respectively supplementary tank 56 arranged opposite of the first tank 14 at the second end 12.2 of teach tube of the plurality of tubes 12.

Like the first tank 14, the supplementary tank 56 may have a tank body 16 forming a cavity 18 having an opening 20 delimited by a peripheral border 22.

Contrary to the first ends 12.1, the second ends 12.2 are not connected to any mounting plates, but are directly fixedly attached to a further header plate 24 closing the opening 18 of the tank body 16 of the supplementary tank 56. Since the first ends 12.1 are already connected to the mounting members 32 and the first sealing means 36.1, the second ends 12.2 do not necessarily require a further arrangement to compensate for stresses and dilatations. Therefore, the second ends 12.2 may be fixedly attached to the header plate 24 directly, e.g. by brazing.

In addition, Fig. 3 and Fig. 4 illustrate also the arrangement of the plurality of tubes 12, wherein the tubes are placed spaced apart and parallel to one another, whereby the plurality of tubes 12 form the central part of the heat exchanger 10.

Although not represented, fins are typically provided between neighboring tubes to improve heat exchange with air.

As can be derived best from Fig. 3, an upper and lower reinforcement element 58 delimit this central element formed by the multiplicity of tubes 12. It is understood that the terms "upper" and "lower" refer to the orientation of the heat exchanger 10 illustrated in Fig. 3. Both elements 58 are fixedly attached to both header plates 24.

Fig. 5 illustrates is a detail cutout view through the tank (left of Fig.4) in plane (X,Y). Fig. 5 shows in particular a section of the tank body 16 of the first tank 14 and the inner cavity 18 of the first tank 14. The tank body 16 has a peripheral border 22 forming a rim-like structure. The second sealing means 40 is arranged on the peripheral border 22 between the tank body 16 and the header plate 24.

14 LUS00978

The header plate 24 is clinched around the peripheral border 22 by two lateral fixing tabs 24.1, whereby the second sealing means 40 is in a compressed state.

The lateral fixing tabs 24.1 of the header plate may be bendable or formable, such that the fixing tabs 24.1 may be bent over the peripheral border 22 of the tank 14 during a clinching or clamping process.

As can be further derived from the embodiment shown in Fig. 5, a mounting member 32 is arranged on the header plate 24 and the peripheral border 22 of the tank 14. Fig. 6 illustrates a perspective view of a corresponding mounting member 32. The mounting member 32 has two lateral fixing arms 38 bended over the fixing tab 24.1 of the header plate 24 and thus also over the peripheral border 22 of the tank body 16 arranged underneath the header plate 22.

It should be noted that according to some embodiments, the tank body 16 and the header plate 24, respectively the interface wall comprising a header plate, may be integrally bound/formed together, respectively may be made integral. In this case, the two lateral fixing arms 38 of the mounting member 32 bend over the peripheral border 22 only. Such an embodiment is also illustrated by Fig. 9.

Fig. 6 illustrates the mounting member 32. The aperture 34 of the illustrated mounting member 32 is delimited by a collar element 34.1 protruding from a flat rectangular body, respectively chassis 34.2 of the mounting member 32. The collar element 34.1 defines the aperture 34 and is configured to directly contact and surround the tube 12, respectively the first end portion 12.1 of the tube 12.

It may be noted that in practice, the tubes 12, mounting member 42 32 and fins may be preassembled and brazed, forming a unitary structure. The tank 14, header plate 24 and gasket 40 are also preassembled. The tube preassembly and tank preassembly are then assembled together with the intermediate sealing elements 36.

Fig. 7 and Fig. 8 illustrate a further embodiment of a heat exchanger 10.

According to this embodiment, the at least first sealing means 36 forms part of a plurality of sealing means 36. Each first sealing means 36 individually surrounds and seals a corresponding respective first end portion 12.1 of the tube 12. The

15 LUS00978 first sealing means 36 are thus separated from one another and spaced apart a small distance.

The heat exchanger illustrated in Figs. 7 and 8 further comprises a second tank 46 arranged adjacent to, respectively above, the first tank 14. The second tank is substantially identical in construction to the first tank 14. Like the first tank 14, the second tank 46 comprises a header plate 24 having oblong through-holes 30 for receiving end portions 12.1 of the tubes 12. Yet it should be noted that the first tank 14 and second tank 46 have each a tank body 16 that is formed integral with a header plate 24. It should be further noted that only the first ends 12.1 engaging in the first tank 14 are provided with a mounting member 32 and a first sealing means 36, whilst the first end 12.1 engaging in the header plate 24 of the second tank 46 are directly connected to the header plate 24 of the second tank 46 by brazing. In other words, merely a sub-set of tube end-portions is equipped with mounting members. This arrangement allows those tubes that are exposed to the highest mechanical stress to be connected to a compensation mechanism (i.e. the first sealing means 36 and the corresponding mounting member 32), while the tubes that are expected to be exposed to only a small temperature gradient are connected directly to the corresponding tank, or directly to the corresponding header plate.

As further illustrated by Fig. 7, the second ends 12.2 of the plurality of tubes 12 are likewise directly attached to a header plater 24 of a supplementary tank 56, wherein the supplementary tank 56 is arranged opposite of the first tank 14 and the second tank 46. The supplementary tank 56 has likewise a tank body 16 that is made integral with a header plate 24.

The first tank 14 further comprises a first cap 50.1 and a second cap 50.2, both caps close the tank body 16. Likewise, the second tank 46 further comprises a first cap 52.1 and a second cap 52.2, which are configured to close lateral ends of the corresponding tank body 16 of the second tank 46.

Fig. 8 is a perspective view of the embodiment illustrated in Fig. 7 in an assembled state, the second cap 50.2 of the first tank 14 and the first cap 52.1 of the second tank 46 contact each other. In other words, the tank body 16 of the

16 LUS00978 first tank 14 and the body 16 of the second tank 46 are separated from one another by the second cap 50.2 of the first tank 14 and the first cap 52.1 of the second tank 46. Similar caps 56.1, 56.2 are provided on lateral ends of the supplementary tank 56.

As can be further seen in Fig. 8 and Fig. 9, the second cap 52.2 comprises an inlet 54. It is understood, that the inlet 54 may alternatively be configured and operated as an outlet. The inlet 54 allows to conduct coolant fluid or (cooling) liquid into the second tank 46. In this respect, the first tank 14 has an outlet (not illustrated) that is connected to an external conduit 60. The external conduit 60 is arranged at an outermost position of the heat exchanger 10 and is thus in fluid communication with the first tank 14. The external conduit is fixed and kept in its place by means of a clip 62 attached to the second tank 46.

Fig. 9 illustrates a further embodiment, wherein the tank body 16 and the interface wall are made integral. In other words, the tank body and the interface wall are formed in one piece. This embodiment may be assembled particularly quickly.

In addition, the heat exchanger 10 illustrated in Fig. 9 may be combined with the mounting plate 32 as illustrated in Fig. 10. It should be noted however, that the mounting plate 32 illustrated in Fig. 10 is not limited to a combination with the embodiment shown in Fig. 9. The mounting plate 32 illustrated in Fig. 10 may be arranged on any suitable tank body or header plate.

The mounting plate 32 illustrated in Fig. 10 comprises a chassis, wherein said chassis 34.2 is formed of a first plate section 34.3 and a second plate section 34.4 arranged at an angle a to each other. The mounting plate 32 may particularly fast and easy be clipped or clinched to a tank body (or header plate).

As can be further derived from Fig. 9, the heat exchanger 10 comprises a first sealing means 36 contacting the end portion 12.1 of the tube 12, the mounting plate 32 as well as the peripheral border 22, which is formed by both, the tank body 16 as well as the interface wall 24.

It should be noted that in alternative embodiments, an additional second sealing means (not illustrated) may be formed between the portions forming the interface wall 24 and the portion forming the tank body 16, even if the interface wall and

17 LUS00978 the tank body are made integral. In this respect, a second sealing means may for example be provided within a groove arranged between the portion forming the tank body and the portion forming the interface wall.

In general, it should be acknowledged that a method for assembling a heat exchanger requires that a plurality of mounting members 32 is formed. This forming comprises in particular a pre-stamping step, wherein an integral mounting member assembly is pre-punched from a (metal) blank, wherein the mounting members are not entirely separated from one another, such that the mounting member assembly comprises a plurality of connected mounting members. The forming of the plurality of mounting members further requires a separation step, which is performed during the mounting of each mounting member of the mounting member assembly, wherein the separation is performed during a clinching step.

Fig. 11, Fig. 12 and Fig. 13 illustrate a further embodiment of a heat exchanger 10 combined with battery cells 80. The tank 16 is built as a manifold, i.e. with integral interface wall 24. The tank body 16 comprises a first cavity 18 and a separate, second cavity 19, which can be seen best in Fig. 13. According to this embodiment, the tubes 12 are arranged in pairs, at the same level. In other words, each tube 12 is arranged adjacently to another tube along a plane transversal to the length (Z) of the tank (here plane defined by the first direction Y and third direction X). The end portions 12.1 of each pair of tubes are inserted in a single mounting member 32.

In this respect, Fig. 14 illustrates a mounting member 32 having two apertures 34, each provided with by an annular collar 34.1.

As can be derived from Fig. 11, Fig. 12 and Fig. 13, the coolant fluid is conducted via an inlet conduct 64 into the first cavity 18 of the tank 14. The coolant fluid is subsequently conducted via a first tube 12 of the pair of tubes to a return cap 68, which comprises a U-shaped conduct (not illustrated). The coolant fluid is subsequently conducted by means of the second tube 12 of the pair of tubes to the second cavity 19 of the tank 14, which is connected to an outlet conduct 66.

18 LUS00978

In this embodiment, where the heat exchanger is designed for application as battery cooler, the tubes 12 are undulated in order to accommodate between them cylindrically shaped battery cell 80. The undulation (waves) of the tubes 12 are adjusted to the battery cell external shape (curvature/diameter) in order to maximize the surface contact and ensure an improved heat transfer between the tubes 12 and the battery cells 80.

It may be noted that the undulated tubes 12 present a connection section 12.3 close to the tank 14 having a length Sp (Fig. 12). This connection section12.3 (typically initially straight as in the drawings) allows shaping the tubes 12 to better adapt to the spacing imposed by the battery cells 80. The shaping of the straight section 12.3 can be done individually, tube by tube, or simultaneously by means of any appropriate tool.

In practice, the pairs of tubes 12 are preassembled and brazed with the respective mounting member 32 and return caps 68. On the assembly line, the thus preassembled tube pairs are fitted with a sealing member 36 around each tube end 12.1, which are then engaged in the respective manifold through holes 30 and the mounting members 32 clinched to the manifold. The battery cells 80 are then put in place between adjacent tube pairs. If needed, the spacing between adjacent tube pairs is modified by bending the respective connection sections 12.3.

Although not shown in the drawings, the assembly of heat exchanger and battery cells is typically disposed in a housing or frame to maintain a compact assembly.

In general, any appropriate means may be used to maintain a compact assembly.

Claims

LUSOPBiED 0978 P-ESHTHO-016/LU CLAIMS

1. Heat exchanger (10) for an automotive application comprising: a plurality of flat tubes (12) for transporting a cooling fluid, in which the flat tubes (12) extend in a first direction (Y); a first reservoir (14) extending over a reservoir length along a second direction (Z) and to which said flat tubes (12) are fluidically connected, in which the reservoir (14) comprises a body (16) having a cavity (18) for said cooling fluid; said first reservoir (14) comprising an interface wall (24) having a rear side (26) facing the cavity (18) and an opposite front side (28), in which the interface wall (24) comprises oblong through holes (30) receiving end portions (12.1) of the flat tubes (12); characterized by a plurality of mounting members (32), each mounting member (32) comprising at least one oblong opening (34) which receives a first end portion (12.1) of a respective tube (12), in which each mounting member (32) is permanently fixed to the interface wall (24) and/or the tank, in a position where the corresponding first end portion (12.1) of the respective tube (12) engages in a respective through hole (30) of the interface wall (24); in which each mounting member (32) is hermetically fixed to said corresponding first end portion (12.1), in particular by brazing; a first sealing means (36) configured to surround at least a first end portion (12.1) of a tube in the plurality of tubes (12), wherein the first sealing means (36) extends between the front side (28) of the interface wall (24) and the respective mounting member (32), thereby the first sealing means (36) supports in a movable manner, in a

LUS0PRE} 0978 fluid-tight, the first respective end part (12.1) of the tube (12) with respect to the interface wall (24).

2. Heat exchanger (10) according to claim 1, in which said tank comprises a tank opening (20) of said cavity (18) delimited by a peripheral border (22) of said tank body (16); and said interface wall is formed by a collector plate (24) closing said tank opening (20).

3. Heat exchanger (10) according to claim 1, in which the tank body (16) and the interface wall (24) are formed as a single unit.

4. Heat exchanger (10) according to any one of the preceding claims, wherein each mounting member (32) has two lateral fixing arms (38) bent over the peripheral edge (22) of the tank body (16) and/or a fixing tab (24.1) of the interface wall (24).

5. Heat exchanger (10) according to any one of the preceding claims, wherein the first sealing means (36) comprises a plurality of separate sealing elements (36.2), one per tube, wherein each sealing element (36.2) comprises a single hole and thus individually surrounds and seals a corresponding respective first end portion

(12.1).

6. Heat exchanger (10) according to any one of claims 1 to 4, wherein the first sealing means comprises a sealing element

(36.1) comprising a number of holes corresponding to the number of through holes in the interface wall, or a part thereof.

7. Heat exchanger according to any one of the preceding claims, further comprising a second sealing means (40), in which the second sealing means (40) is arranged on the peripheral edge (22) between the rear side (26) of the interface wall (24) and the tank body (16).

LUSOPBiED 0978

8. Heat exchanger (10) according to any one of the preceding claims, further comprising a second tank (46) arranged adjacent to the first tank (14), in which the interface wall (24) of the second tank (46) comprises oblong through holes (30) receiving first end portions (12.1) of corresponding tubes (12), in which the first end portions (12.1) are directly attached to the through holes of the interface wall (24) of the second tank (46) by brazing.

9. Heat exchanger (10) according to claim 8, wherein the first reservoir (14) further comprises a first plug (50.1) and a second plug (50.2), wherein the second reservoir (46) further comprises a first plug (52.1) and a second plug (52.2), and wherein the second plug (50.2) of the first reservoir (14) and the first plug

(52.1) of the second reservoir (46) are in contact with each other, so that the body (16) of the first reservoir (14) and the body (16) of the second reservoir (46) are separated from each other by the second plug (50.2) of the first reservoir (14) and the first plug (52.1) of the second reservoir (46).

10. Heat exchanger (10) according to claim 9, wherein the second plug (52.2) includes an inlet (54).

11. Heat exchanger (10) according to any one of the preceding claims, wherein the heat exchanger (10) further comprises an additional tank (56) extending over a tank length along the second direction (Z) and to which a plurality of second end portions

(12.2) of the plurality of tubes (12) are fluidly connected, in which the additional reservoir (56) is arranged opposite to the first reservoir (14).

12. Heat exchanger (10) according to any one of the preceding claims, wherein the opening (34) of each mounting member (32) is delimited by a collar element (34.1) projecting from a frame (34.2) of — the mounting member (32).

LUS0PRE} 0978

13. Heat exchanger (10) according to claim 12, wherein the frame (34.2) comprises a first plate section (34.3) and a second plate section (34.4) forming an angle with respect to each other.

14. Heat exchanger (10) according to any one of the preceding claims, wherein at least the first reservoir (14) is made of or comprises one of the following: a plastic, a polyamide, a polypropylene, a resin, a thermoplastic, or mixtures thereof.

15. Heat exchanger (10) according to any one of the preceding claims, wherein each tube of the plurality of tubes (12) comprises or is made of a weldable metal, wherein the metal comprises aluminum.

16. Heat exchanger (10) according to any one of the preceding claims, wherein the first sealing means (36) is made of or comprises at least one of the following: a rubber, a plastic, a polymer-based material, an ethylene-propylene-diene monomer (rubber), or mixtures thereof.

17. Heat exchanger (10) according to any one of the preceding claims, in which each mounting member (32) is provided with a single opening.

18. Heat exchanger (10) according to any one of the preceding claims, wherein the mounting member (32) comprises between two and five openings (34) arranged adjacently one above the other.

19. Heat exchanger (10) according to claim 17 or 18, wherein the sealing member comprises a number of holes corresponding to the number of openings in the mounting member (32).

20. Heat exchanger (10) according to any one of the preceding claims, wherein the mounting member (32) comprises two openings (34) arranged side by side.

LUSOPBiED 0978

21. Heat exchanger (10) according to claim 20, wherein the mounting member (32) comprises two openings (34) arranged side by side at the same level along a length direction of the tank, whereby the tubes are arranged in pairs and tightly bound 5 in a respective opening, whereby the tubes are corrugated along their length direction to house, between adjacent pairs of tubes, cylindrical battery elements (80).

22. Heat exchanger (10) according to claim 21, in which a connecting section (12.3) of the tube separates the collector from the first corrugation.

23. Method of assembling a heat exchanger (10) according to any one of the preceding claims, wherein the method comprises: the formation of a plurality of mounting members (32), wherein the formation of the plurality of mounting members (32) comprises - the pre-stamping of an assembly of integrated mounting members, and - the separation of each mounting member from the assembly of pre-stamped mounting members during a clinching step.

24. A method of operating a heat exchanger according to any one of claims 8 to 22, wherein the method comprises: - conveying a cooling fluid stored inside the second tank (46) out of the second tank (46); and subsequently - conveying said cooling fluid into the first tank (16).