WO2024017684A1

WO2024017684A1 - Thermal module comprising a ventilation duct mounted on a heat exchanger

Info

Publication number: WO2024017684A1
Application number: PCT/EP2023/069042
Authority: WO
Inventors: Remi Tournois; Sebastien Riviere
Original assignee: Valeo Systemes Thermiques
Priority date: 2022-07-19
Filing date: 2023-07-10
Publication date: 2024-01-25
Also published as: FR3138190A1; FR3138190B1

Abstract

The present invention relates to a thermal module (1) comprising a ventilation duct (2) and a heat exchanger (3), the ventilation duct (2) having a face comprising an air inlet (4) and an opposite face sealingly mounted on the heat exchanger (3), the duct (2) and the heat exchanger (3) being attached to one another via the attachment means of the thermal module (1), the attachment means comprising at least one tie device, the thermal module (1) being characterised in that the attachment means also comprise means for holding the duct (2) against the heat exchanger (3) in a longitudinal direction (X) orthogonal to the faces of the duct (2), the holding means comprising a fusible portion rigidly attached to the duct (2).

Description

THERMAL MODULE COMPRISING A VENTILATION DUCT MOUNTED ON A HEAT EXCHANGER

The present invention relates to the field of heat exchange systems for vehicles, and more specifically concerns a thermal module comprising a ventilation duct mounted on a heat exchanger.

In vehicles, it is known to provide thermal modules arranged on the front of the vehicle which are configured in particular to recover large quantities of fresh air and to allow an exchange of calories between the flow of fresh air passing through it and different fluids. heat carriers or refrigerants circulating through heat exchange devices, such as radiators or condensers. The fluid(s) thus cooled or heated are also used in thermal loops, for example for air conditioning of the vehicle passenger compartment and/or for cooling circuits of vehicle components such as batteries for example.

Such a thermal module is therefore fixed in the front compartment of the vehicle so that the outside air enters an air inlet of a ventilation duct bringing this outside air to the heat exchanger. The air inlet is therefore the element of the heat exchanger closest to the front of the vehicle, to receive the air arriving from the vehicle grille as directly as possible.

In the event of a frontal impact, the ventilation duct is likely to be deformed, whether under the effect of the movement of the grille or other equipment placed between the grille and the heat exchanger, for example a grille with shutters controlled, particularly at the air inlet. Continuing the shock, the ventilation duct impacts the heat exchanger. It is then necessary to dismantle the ventilation duct and the heat exchanger, and replace or repair them, which is complex and expensive. The ventilation duct is less heavy but due to its extended vertically in the front compartment, it is difficult to access the lower ends of the ventilation duct to remove them from the heat exchanger.

There is therefore a need for a thermal module composed of a ventilation duct mounted on a radiator-type heat exchanger, which is much simpler and less expensive to repair in the event of a frontal impact.

In this context, the present invention proposes a thermal module comprising a ventilation duct and a heat exchanger, the ventilation duct having a face comprising an air inlet and an opposite face mounted in a sealed manner on the heat exchanger, said duct and said heat exchanger being fixed to one another by means of fixing the thermal module, the fixing means comprising at least one fastening device, said thermal module being characterized in that the fixing means further comprise means for holding said conduit against said heat exchanger in a longitudinal direction orthogonal to said faces of said conduit, said holding means comprising a fuse part integral with said conduit.

The thermal module according to the invention is shaped to be placed in a front compartment of a vehicle, with the air inlet which is fixed closest to the front of the vehicle, with its back to the passenger compartment. The longitudinal direction as defined is substantially parallel to the main direction of air flow through the heat exchanger. This longitudinal direction can be parallel to the longitudinal direction of the vehicle when the thermal module is mounted on the vehicle. The holding means are preferably arranged at a portion of the ventilation duct comprising the air inlet, for example on one or more side walls of the ventilation duct proximal to this air inlet.

Thanks to the invention, during a frontal impact causing the ventilation duct to deform, the fuse part integral with the ventilation duct breaks or deforms, which makes it possible to absorb part of the shock, without damaging the heat exchanger. The fuse part attached to the ventilation duct comes from the material with the ventilation duct or is a part attached to the ventilation duct by any fixing.

The fixing means comprising the attachment device(s) can be configured to allow direct fixing of the conduit to the heat exchanger or indirect fixation, where appropriate via additional elements interfacing between the heat exchanger and the conduit .

According to a characteristic of the invention, said holding means comprise two stops secured to said conduit or said heat exchanger being offset relative to each other in said longitudinal direction, and a part secured respectively to said heat exchanger or said conduit , able to be blocked between said two stops in said longitudinal direction. This way of producing the holding means makes it possible to easily dismantle the ventilation duct because the holding means only fix the longitudinal position of the ventilation duct. This can therefore be removed from the heat exchanger by dismantling the attachment device then lifting the ventilation duct, possibly after a slight rotation of the latter relative to the main elongation plane of the heat exchanger.

According to a characteristic of the invention, at least one of the two stops comprises a chamfer capable of facilitating the insertion of said part between said stops.

According to one characteristic of the invention, the two stops are arranged on a tongue extending one or the other of said heat exchanger or said conduit, said tongue incorporating a clearance between said fuse part and respectively said heat exchanger or said conduit. The clearance thus created between the fuse part and the main body of the device or the duct allows the heat exchanger to undergo, without damage, moderate advancement of the ventilation duct towards the heat exchanger in the event of a frontal impact. This clearance therefore extends in the longitudinal direction orthogonal to said faces of the ventilation duct. According to one characteristic of the invention, a seal is compressed between side walls of the ventilation duct and side walls of the heat exchanger.

According to one characteristic of the invention, said tongue extends said heat exchanger towards said conduit, and said stops are offset from one another in a vertical direction extending parallel to a side wall of said heat exchanger on which said said heat exchanger is mounted. tongue, said part comprising a rod secured to said conduit and a terminal plate extending said rod, said terminal plate being housed between said stops. This offset of the stops in two orthogonal directions on the tongue makes it possible to place the part obliquely between the two stops, which provides vertical maintenance of the ventilation duct in the heat exchanger, when the side wall of the heat exchanger on which is mounted the tab is arranged vertically in the vehicle. This configuration of the holding means also facilitates the rotation of the part between the stops and therefore the assembly or disassembly of the ventilation duct on the heat exchanger.

According to one characteristic of the invention, said fuse part is a groove on said terminal plate, said groove being positioned between the two stops between which said terminal plate is placed. The groove is preferably arranged on the surface of the end plate facing the main body of the ventilation duct. So during a frontal impact the groove breaks more easily.

According to one characteristic of the invention, the terminal plate comprises two contact portions with the stops, said contact portions being arranged on either side of a central portion of the terminal plate, a groove delimiting each of the two contact portions with said central portion. This way of producing the part makes it possible to use an identical part for each of the means for holding the thermal module when these holding means are doubled so as to have them on opposite side walls of the thermal module. When the heat exchanger includes a radiator having side water boxes arranged vertically in the vehicle, the holding means are for example arranged on each of these water boxes and on corresponding side walls of the ventilation duct.

According to a characteristic of the invention, said tongue extends said conduit towards said heat exchanger and said part is a cylindrical pin secured to said heat exchanger, one of the two stops proximal to said conduit comprising a notch forming said clearance and closed by a breakable strip, said breakable strip being in contact with said pin. By “closed” here we mean at least partially closed, the important thing being that the breakable strip blocks the movement of the pin in the notch outside of a frontal impact situation. It should be noted that this alternative embodiment only allows vertical maintenance of the ventilation duct in the vehicle by the pressure exerted on the pin by the elastic return force of the breakable slat, and that it may be necessary to provide a specific stop on the heat exchanger.

According to one characteristic of the invention, said at least one attachment device is a snap-fit attachment device. This allows easy assembly and reassembly of the ventilation duct on the heat exchanger, in particular without screws.

According to a characteristic of the invention, said fixing means further comprise means for guiding said conduit on said heat exchanger in said longitudinal direction.

According to a characteristic of the invention, said fixing means further comprise an anti-vibration device disposed between the heat exchanger and the ventilation duct. This anti-vibration device is for example an elastomer or a flexible strip placed on one or more snap-fastening devices or on the holding means. It makes it possible to guarantee the position of the ventilation duct relative to the heat exchanger in the longitudinal direction, to limit vibrations when the vehicle is rolling, and to avoid tolerance problems due to the manufacturing of the ventilation duct and the heat exchanger. According to one characteristic of the invention, the heat exchanger comprises a radiator and a motorized fan.

The invention also relates to a method of mounting the thermal module according to the invention, comprising at least the steps of:

- positioning of said part between said two stops by carrying out a translation movement of said conduit with an angle of attack inclined relative to a main elongation plane of the thermal module,

- rotation of said conduit around an axis parallel to said main elongation plane and located between said two stops,

- fixing said conduit via said at least one fastening device.

The assembly method according to the invention has advantages similar to those of the thermal module according to the invention.

Other characteristics and advantages of the invention will appear further through the description which follows on the one hand, and several examples of embodiment given for informational and non-limiting purposes with reference to the appended schematic drawings on the other hand, in which :

[fig 1] illustrates a thermal module according to the invention, in a first embodiment of the invention, comprising in particular a ventilation duct and a heat exchanger,

[fig 2] is a perspective view of a part of means for holding the thermal module according to the invention, in the first embodiment of the invention, intended to be integral with the ventilation duct,

[fig 3] is a sectional and perspective view of other elements of holding means, intended to be integral with the heat exchanger, in the first embodiment of the invention,

[fig 4] is a sectional view of the thermal module according to the invention at the level of means for maintaining the thermal module according to the invention, in the first embodiment of the invention, making in particular visible the cooperation between the part of Figure 2 and the elements of Figure 3, [fig 5] is a perspective view of a water box of the heat exchanger making visible the elements of the holding means of Figure 3,

[fig 6] is a perspective view of the thermal module according to the invention, seen from above to show more particularly a portion of the upper end of this module,

[fig 7] is a perspective view of a snap-fastening device on the upper end portion of Figure 6,

[fig 8] is a perspective view of elements of holding means on a part of a thermal module according to the invention, in a second embodiment of the invention,

[fig 9] is a perspective view of an element of holding means on another part of the thermal module according to the invention, in the second embodiment of the invention,

[fig 10] is a perspective view of the thermal module making visible the cooperation of the holding means, in the second embodiment of the invention, and

[fig 11] is a sectional view of the thermal module according to the invention at the level of the holding means of Figure 10.

As a reminder, according to the invention, a thermal module 1 comprises at least one ventilation duct 2 and a heat exchanger 3, fixed to one another by appropriate fixing means including a fastening device 40, and holding means comprising a fuse part 86, 248 secured to said conduit 2.

A first embodiment of the invention is illustrated in Figures 1 to 7.

The ventilation duct 2 has an air inlet 4 on a front face of the ventilation duct 2. Opposite this front face, the air entering this air inlet 4 arrives on a rear face of the ventilation duct 2 mounted sealed on the heat exchanger 3. At the interface between the ventilation duct 2 and the heat exchanger 3, the ventilation duct 2 and the heat exchanger 3 each have side walls, the whole of which has a generally rectangular frame shape. The seal between the ventilation duct 2 and the heat exchanger 3 is ensured by a seal 5 of the same overall shape, this seal being compressed between the side walls of the ventilation duct 2 and the side walls of the exchanger thermal 3. The seal 5 is preferably made of flexible material in order to facilitate the mounting of the ventilation duct 2 on the heat exchanger 3 and to absorb vibrations on the thermal module 1. This material is for example EPDM (ethylene-propylene-diene monomer).

The heat exchanger 3 extends in a main elongation plane substantially parallel to the inlet and outlet faces of the ventilation duct 2. By substantially parallel we mean that a variation of up to 15 degrees between the main elongation plane and the entry and exit faces is possible. The main elongation plane of the thermal module 1 therefore extends in the transverse Y and vertical Z directions of the orthonormal reference shown in Figure 1. It should be noted that this arrangement is only an example and that the thermal module could present another orientation without departing from the context of the invention.

The air inlet 4 extends upstream of the heat exchanger 3 if we consider a direction of longitudinal elongation X, perpendicular to the transverse and vertical directions which have just been defined.

The air inlet 4 extends from one end to the other of the thermal module 1, in the transverse direction Y, and it extends partially over the vertical dimension Z.

In the example illustrated, the air inlet 4 of the thermal module 1 defines a lower end portion 7 of the thermal module, opposite a upper end portion 6 of the thermal module 1. The upper end portion 6 is arranged above the lower end portion 7 in the Z direction of the orthonormal reference shown in Figure 1, which is a vertical direction associated with the thermal module 1. The X direction of the orthonormal reference shown in Figure 1, orthogonal to the main elongation plane of the thermal modulei, is a longitudinal direction associated with the thermal module 1. Finally the direction Y of the orthonormal reference represented in Figure i, orthogonal to the longitudinal directions X and vertical Z of the thermal module i, is a transverse direction associated with the thermal module i.

These directions are named in reference to the positioning of the thermal module i in a motor vehicle in which it is intended to be mounted. In fact, the thermal module 1 is mounted in a front compartment of the vehicle, the air inlet 4 facing a front end of the vehicle, to receive the air directly when the vehicle is rolling. The longitudinal direction X therefore corresponds to the longitudinal direction of the vehicle. The vertical direction Z also corresponds to the vertical direction of the vehicle, the high end portion 6 being positioned above the low end portion 7 in the vehicle, it being understood that the thermal module can be mounted with an inclination relative to the vertical. Of course, in other embodiments, the arrangement of the thermal module is different, the air inlet possibly being in the upper end portion of the thermal module.

In this first embodiment of the invention, the heat exchanger 3 is a radiator which is intended to transfer calories to the air circulating in the ventilation duct 2 and passed through the radiator. This radiator comprises two water boxes forming the side walls of the heat exchanger 3 which extend in the vertical direction Z of the thermal module 1. In the upper part, that is to say in the upper end portion 6 , these water boxes have screw holes 38 making it possible to fix the heat exchanger 3 on a longitudinal member of the vehicle, in particular by screwing. A motorized fan (not shown) is fixed behind the body of the radiator and makes it possible to accelerate the passage of air in the ventilation duct 2 to improve the cooling of the heat exchanger liquid also circulating in the radiator.

The ventilation duct 2 is preferably made of flexible material, for example of homopolymer polypropylene reinforced with talc, or of another polymer material, to absorb the air pressure, when the vehicle in which the thermal module 1 is mounted is rolling. at high speed. The conduit 2 of ventilation is fixed to the heat exchanger 3 by fixing means comprising a fastening device and holding means.

The attachment device is formed here by two snap-fit attachment devices 40 arranged on the upper end portion 6, on either side of the thermal module 1 in the transverse direction thereof. These fixing means will be detailed later in relation to Figure 6.

The holding means are arranged at the level of the lower end portion 7. It should be noted that the upper or lower arrangement of the fixing means according to the vertical dimension Z is arbitrary here. It is notable that the holding means are arranged at the level of the ventilation duct 2, if we consider the vertical dimension as previously mentioned. Therefore, a deformation according to a longitudinal or transverse component, created by a frontal impact that the vehicle is likely to encounter, of the ventilation duct at the level of the air inlet, directly impacts the holding means, which are not offset vertically relative to the air inlet regardless of the position of the air inlet on the ventilation duct.

The holding means make it possible to hold the ventilation conduit 2 against the heat exchanger 3 in the longitudinal direction of the thermal module 1, in particular by means of a part 8 shown in Figure 2 and comprising a fuse part, here thanks to the presence of grooves 86.

The part 8 is made of rigid synthetic material, for example polypropylene reinforced with glass fibers, it being understood that another polymer material can be chosen, and comprises a base 80 secured by snap-fastening to the ventilation duct 2 via an elastic blade 88 of part 8, this elastic blade 88 comprising a free end forming a hook capable of getting stuck in a corresponding ring 22 of the ventilation duct 2, visible in Figure 4. Part 8 further comprises a rod 82 connecting the base 80 and an end plate 84 of the part 8, the end plate 84 extending substantially perpendicularly the rod 82. This end plate 84 comprises a central portion 843, delimited by two grooves 86 beyond which are located contact portions 841 and 842 of the plate terminal 84. The grooves 86 help to form breakable contact portions. The grooves 86 are arranged on the surface of the terminal plate 84 facing the main body 2 of the ventilation duct. So during a frontal impact they break more easily. These contact portions 841 and 842 in fact form lateral ends of the terminal plate 84 coming, when the ventilation duct 2 is mounted on the heat exchanger 3, in contact with stops 320 and 322 of the heat exchanger 3, visible on Figure 3 in particular, and their breakable nature allows, in the event of a frontal impact, in a substantially longitudinal direction, the part 88 to no longer be in contact with the stops and to allow the movement of the rod and consequently of the conduit 2 of ventilation on which the base 80 of part 8 is fixed.

The stops 320 and 322 are here secured to a water box of the radiator of the heat exchanger 3 and are therefore placed on a vertical side wall of the heat exchanger 3. Alternatively, the stops 320 and 322 are secured to a frame of the heat exchanger 3, allowing the fixing of this heat exchanger 3 within the front compartment of the vehicle. The other vertical side wall of the heat exchanger 3 includes holding means similar to those described here and bear the same references. Thus the part 8 has two grooves 86 because depending on the position of this part 8 on the thermal module 1, one or the other of these two grooves 86 serves as a fuse part during an impact on the conduit 2 of ventilation as explained below.

More precisely, the stops 320 and 322 are formed on a tongue 324 extending the side wall of the heat exchanger 3 in the longitudinal direction of the thermal module 1. The stops 320 and 322 extend projecting from the tongue 324, in a elongation plane substantially perpendicular to the tongue 324, and in particular in the transverse direction of the thermal module 1, being offset from one another in the longitudinal direction of the thermal module 1. This longitudinal offset is less than the thickness of the terminal plate 84 at the level of its contact portions 841 and 842, which requires positioning the terminal plate slightly obliquely between these two stops 320 and 322. They are also offset in the vertical direction of the thermal module 1. Thus they allow of block the part 8 in the longitudinal direction of the thermal module i, as shown in the sectional view in Figure 4, on which the part 8 is mounted slightly obliquely between the two stops 320 and 322. In fact, a first stop 320 blocks a contact portion 841 of the terminal plate 84 of part 8 in the direction of thrust of the ventilation duct 2 towards the heat exchanger 3, and the second stop 322 blocks the other contact portion 842 of the terminal plate 84 of part 8 in the opposite direction. The first stop 320, located above the second stop 322, is closer to the body of the heat exchanger than the stop 322, in order to facilitate the mounting of the ventilation duct 2 on the heat exchanger 3, in particular by a slight rotation of part 8 between these two stops 320, 322.

When an impact on the vehicle, in which the thermal module 1 is mounted, pushes the ventilation duct 2 onto the heat exchanger 3, the ventilation duct 2 deforms, thanks to the flexible material constituting it, so as to absorb part of the energy. The part 8 breaks at one of the grooves 86 forming a frangible part, and the rod 82 is housed in a clearance 328 arranged longitudinally on the heat exchanger 3 between the stops 320, 322 and part of the tongue 324 proximal to the rest of the heat exchanger 3. More particularly here, in the example illustrated, it is at the level of the first stop 320 that the breakage of the part 88 takes place, since the shock tends to push the portion contact portion 842 against this first stop 320, while it tends to move the other contact portion 841 away from the second stop 322.

The clearance 328 combined with this deformation of the ventilation duct 2 allows the thermal module to absorb a frontal impact of the "RCAR Crash" type (from the English "Research Council for Automative Repairs") on the vehicle, without damaging the vehicle. heat exchanger 3.

The means for holding the ventilation conduit 2 on the heat exchanger 3 therefore comprise means 32 consisting of the tongue 324 and the stops 320,322 arranged on the heat exchanger 3, and of the part 8 secured to the ventilation conduit 2. In the event of a longitudinal impact, only the part 8 of the ventilation duct 2 is damaged and it is therefore sufficient to dismantle the ventilation duct 2 to repair or replace it, leaving the heat exchanger 3 mounted in the vehicle. For this purpose, it is necessary to manipulate the snap-fastening devices 40 participating in forming the fixing means to very easily mount and disassemble the ventilation duct 2.

The snap-fastening devices 40, visible in Figures 6 and 7, each comprise a ring 401 secured to the ventilation duct 2, which blocks a corresponding snap-fit finger 402 mounted here integrally with a water box of the radiator of the heat exchanger 3. Of course as a variant, the snap-fastening devices 40 each comprise a ring secured to the heat exchanger 3, blocking a corresponding snap-in finger mounted securely on the ventilation duct 2. In this variant as well as in the main variant embodiment of the invention, these snap-fastening devices 40 are shaped so that a push on the lower end portion 7 of the thermal module 1 at the level of the ventilation duct 2 , causes the ventilation duct 2 to detach from the heat exchanger 3 in the upper end portion 6.

Furthermore, in this first embodiment of the invention, the snap-fastening devices 40 each comprise, integrally mounted on the ring 401, a flexible blade 403 bearing on the heat exchanger 3. This flexible blade has dimensions and elastic return characteristics such that the blade is compressed when the detent finger 402 cooperates with the ring 401 and tends to move the ventilation duct 2 and the heat exchanger 3 away from each other to ensure fixing of the snap-in finger against the ring The flexible blade thus also constitutes an anti-vibration device.

The means for fixing the thermal module 1 also comprise means for longitudinally guiding the ventilation duct 2 on the heat exchanger 3. This guiding means comprises a tongue 26 curved at its end and secured to its base of the ventilation duct, and a buttonhole 36 secured to the heat exchanger 3. The tongue 26 is integral with the ventilation duct 2. The tongue 26 and the buttonhole 36 are each arranged on a central zone of a side wall of the ventilation duct 2 or of the heat exchanger 3, this side wall extending transversely to the thermal module 1 in its upper end portion 6. The tongue 26 is inserted into the buttonhole 36 during assembly of the thermal module 1, the curved end of the tongue 26 blocking the tab 26 in the buttonhole 36.

A method of mounting the thermal module 1 in this first embodiment of the invention will now be described.

It notably comprises a step of positioning the part 8 between the two stops 320, 322 by moving the conduit 2 substantially vertically, the lower end portion 7 preceding the upper end portion, with an angle of attack inclined relative to to the main elongation plane of the thermal module i.The insertion of the part 8 between the two stops 320, 322 is facilitated by the presence of chamfers 326 smoothing the edges of the stops 320, 322 coming into contact with the part 8, such that this is visible in Figure 3 in particular.

The assembly process continues with a rotation of the conduit 2 around an axis parallel to the transverse direction Y to the thermal module 1, this axis being formed by the contact of the part 8 with one or the other of the two stops 320, 322. The rotation makes it possible to simultaneously press each of the contact portions 841, 842 of the part 8 with its corresponding stop 320, 321, and to bring the ventilation duct 2 into contact with the heat exchanger 3 at the level of the upper end portion of the thermal module 1.

The assembly process ends with the fixing of said conduit 2 on said heat exchanger 3 via the guiding means and the snap-fastening devices 40.

In this first embodiment of the invention, the ventilation duct is therefore not attached at the level of the lower end portion of the thermal module 1, but only blocked longitudinally by a contact of the part 8 in a first direction longitudinal with the first stop 320 and in a second longitudinal direction with the second stop 322. The part 8 is also held transversely by the tongue 324, at least in one direction, and held vertically, in one direction, by abutment of the rod 82 on the second stop 322.

We will now describe a second embodiment, with reference to Figures 8 to 11, which differs from what was previously described by the structure of the holding means. The identical elements between the first embodiment and the second embodiment therefore bear the same references and will not be detailed further.

In this second embodiment of the invention, the holding means, formed on the lower end portion 7 of the thermal module 1, comprise means 24 arranged on the ventilation duct 2, visible in Figure 8, and a cylindrical pin 34 on the heat exchanger 3, visible in Figure 9. The means 24 on the ventilation conduit 2 comprise a tongue 240 extending a side wall of the ventilation conduit 2, this side wall extending in a longitudinal direction of the thermal module 1. The tongue 240 comprises two stops 242 and 244 offset relative to each other in the longitudinal direction of the thermal module 1, and blocking the pin 34 of the heat exchanger 3, as visible in Figures 10 and 11.

A first stop 244, or proximal stop due to its position relative to the main body of the ventilation duct 2, comprises a notch 246 closed at least partially by an elastic strip 248, articulated on the first stop at the entrance to the notch. It is understood that the strip 248 is of small thickness so that it forms the fuse part of the stop 244. The breakable or deformable strip 248 comes from one piece with the ventilation duct 2 and has an elasticity which makes it an anti-vibration device arranged between the ventilation duct 2 and the heat exchanger 3. Therefore, in a variant of this second embodiment of the invention, the flexible strips of the snap-fastening devices such as they were mentioned in the first embodiment are not necessary for the vibration resistance of the thermal module 1. As in the first embodiment of the invention, in this second embodiment of the invention, similar holding means are located at opposite transverse ends of the thermal module i, on the vertical side walls of the thermal module i. In particular a pin 34 is arranged on each of the water boxes of the radiator of the thermal module 1.

In this second embodiment of the invention, when an impact on the vehicle in which the thermal module 1 is mounted, pushes the ventilation duct 2 onto the heat exchanger 3, the pin 34 pushes on the strip 248 which is breaks or deforms, and is lodged in the notch 246 which forms a longitudinal clearance for the pin 234, in order to accompany the longitudinal movement of the main body of the ventilation duct 2 relative to the heat exchanger 3.

In the event of a longitudinal impact, only the means 24 of the ventilation duct 2 are damaged and it is therefore sufficient to dismantle the ventilation duct 2 to repair or replace it, leaving the heat exchanger 3 mounted in the vehicle.

A method of mounting the thermal module 1 in this second embodiment of the invention will now be described.

It includes in particular a step of positioning the two stops 242, 244 around the pin 34 by moving the conduit 2 substantially vertically, the lower end portion 7 preceding the upper end portion 6, with an angle of attack inclined relative to to the main elongation plane of the thermal module 1. The insertion of the two stops 242, 244 around the pin 34 is facilitated by the presence of chamfers smoothing the edges of the stops 242, 244 coming into contact with the pin 34 during this insertion.

The assembly process continues with a rotation of the conduit 2 around an axis parallel to the transverse direction Y to the thermal module 1, this axis being defined by the pin 34. During this rotation, the ventilation conduit 2 is brought in contact with the heat exchanger 3 at the upper end portion of the thermal module 1.

The assembly process ends with the fixing of said conduit 2 on said heat exchanger 3 via the guide means and the snap-fastening devices 40.

In accordance with what was mentioned in the first embodiment, in this second embodiment of the invention, the ventilation duct is not attached at the level of the lower end portion of the thermal module 1, but only blocked longitudinally thanks to the pin 34 of the heat exchanger 3, located between the two stops 242, 244 of the ventilation duct 2. The spring effect of the elastic strip also tends to block the pin 34 in relation to the stops according to vertical and transverse components.

Of course, the invention is not limited to the examples which have just been described and numerous adjustments can be made to these examples without departing from the scope of the invention. In particular, the fuse part has as a variant a foldable and non-breakable portion, for example on the rod 82. In another variant the holding means are arranged on transverse side walls of the ventilation duct 2 and of the heat exchanger 3 on a other area than the lower end portion 7 of the thermal module 1, for example on a central portion of each of these side walls. Furthermore, it should be noted that heat exchanger 3 is not necessarily a radiator with water boxes and that it may be another type of heat exchanger.

Claims

1- Thermal module (1) comprising a ventilation duct (2) and a heat exchanger, the ventilation duct (2) having one face comprising an air inlet (4) and an opposite face mounted in a sealed manner on the heat exchanger (3), said conduit (2) and said heat exchanger (3) being fixed to each other by means of fixing the thermal module (1), the fixing means comprising at least one device for fastener (40), said thermal module (1) being characterized in that the fixing means further comprise means for holding said conduit (2) against said heat exchanger (3) in a longitudinal direction (X) orthogonal to said faces of said conduit (2), said holding means comprising a fuse part (86, 248) integral with said conduit (2).

2- Thermal module (1) according to claim 1, in which said holding means comprise two stops (320, 322, 242, 244) integral with said conduit (2) or with said heat exchanger (3) being offset one by relative to the other in said longitudinal direction (X), and a part (8, 34) secured respectively to said heat exchanger (3) or to said conduit

(2), capable of being blocked between said two stops (320, 322, 242, 244) in said longitudinal direction (X).

3- Thermal module (1) according to claim 2, in which at least one of the two stops (320, 322, 242, 244) comprises a chamfer (326) capable of facilitating the insertion of said part (8, 34) between said stops (320, 322, 242, 244).

4- Thermal module (1) according to any one of claims 2 to 3, in which the two stops (320, 322, 242, 244) are arranged on a tongue (324, 240) extending one or the other of said heat exchanger

(3) or said conduit (2), said tongue (324, 240) incorporating a clearance (328, 246) between said fuse part (86, 248) and respectively said heat exchanger (3) or said conduit (2). 5- Thermal module (i) according to claim 4, in which said tongue (324) extends said heat exchanger (3) towards said conduit (2), and in which said stops (320, 322) are offset one from the other in a vertical direction extending parallel to a side wall of said heat exchanger on which said tongue is mounted, said part (8) comprising a rod (82) integral with said conduit (2) and an end plate (84) extending said rod (82), said end plate (84) being housed between said stops (320, 322).

6- Thermal module (1) according to the preceding claim, in which said fuse part is a groove (86) on said terminal plate (84), said groove (86) being positioned between the two stops (320, 322) between which said end plate (84) is placed.

7- Thermal module (1) according to the preceding claim, in which the terminal plate (84) comprises two contact portions (841, 842) with the stops (320,322), said contact portions (841, 842) being arranged on either side and on the other hand a central portion (843) of the terminal plate (84), a groove (86) delimiting each of the two contact portions (841, 842) with said central portion (843).

8- Thermal module (1) according to claim 4, in which said tongue (240) extends said conduit (2) towards said heat exchanger (3) and in which said part (34) is a cylindrical pin integral with said heat exchanger (3) ), one of the two stops (244) proximal to said conduit (2) comprising a notch (246) forming said clearance and closed by a breakable strip (248), said breakable strip (248) being in contact with said pin.

9- Thermal module (1) according to any one of claims 1 to 8, wherein said at least one attachment device is a snap-fit attachment device (40).

10- Thermal module (1) according to the preceding claim, wherein said fixing means further comprise means for guiding (26) said conduit (2) on said heat exchanger (3) in said longitudinal direction. il- Method of mounting a thermal module (i) according to any one of the preceding claims taken in combination with claim 2, comprising at least the steps of:

- positioning of said part (8,34) between said two stops (320,322,242,244) by carrying out a translation movement of said conduit

(2) in a plane inclined relative to a main elongation plane of the thermal module (1),

- rotation of said conduit (2) around an axis parallel to said main elongation plane and located between said two stops (320,322,242,244),

- fixing said conduit (2) via said at least one attachment device.