FR3105718A1 - Cooling system of an electronic device and an electronic system comprising such a cooling system - Google Patents

Abstract

The invention relates to a cooling system (700'') for an electronic component (T10) of an electronic device (400) comprising a case (100) comprising at least one wall, a first face of said wall facing the exterior of said casing (100) and a second face (130) of said wall facing the interior of said casing (100), said casing (100) comprising a cavity (150) formed in said wall on the side of said second face (130), and a separation cover (200) resting on said second face (130) and fixed to said wall so as to close said cavity (150) and to delimit a first volume of the case (100) in which a cooling fluid is intended to circulate relative to a second volume of the case (100) in which said electronic device (400) is intended to be positioned, said separation cover (200) comprising a heat sink (200) intended to cool the minus said electronic component (T10) of said d electronic device (400), said heat sink (200) including at least one fin (220), said at least one fin (220) extending into said first volume. Figure for abstract: Figure 1

Description

System for cooling an electronic device and electronic system comprising such a cooling system

The present invention relates to a cooling system for an electronic device and an electronic system comprising such a cooling system.

The invention also relates to an electric charger or a voltage converter comprising such a cooling system.

The invention also relates to a method of manufacturing such a cooling system.

TECHNOLOGICAL BACKGROUND

Cooling systems for electronic devices comprising a casing made in a foundry are known. This type of box comprises at least one wall, a first face of said wall being turned towards the outside of said box and a second face of said wall being turned towards the inside of said box, said box comprising a cavity formed in said wall of the side of said first face, and a cover intended to bear against said first face so as to close said cavity and to delimit a channel for circulation of a cooling fluid. The cover is generally held on the case with screws. A seal is also positioned between the cover and the box to seal the cooling channel. To improve the cooling of the electronic components, the walls of the cavity of the case include fins.

A first drawback of this known solution lies in the fact that the casing, the cavity and the fins are produced simultaneously in a single casting, which prevents any modular design of such a cooling system.

In addition, the construction constraints of the case, the cavity and the fins must be taken into account simultaneously during the manufacture of such a cooling system, which limits the minimum thickness of the fins that can be produced, and thereby the performance of cooling of cooling systems according to the prior art.

Indeed, for a foundry manufacturing process, the fineness of the fins and their tolerance intervals are determined by the largest dimension of the dimensions of the case.

The object of the present invention is to solve the drawbacks described above.

To this end, it is proposed, according to a first aspect of the invention, a system for cooling an electronic component of an electronic device comprising:

• a casing comprising at least one wall, a first face of said wall being turned towards the outside of said casing and a second face of said wall being turned towards the inside of said casing, said casing comprising a cavity formed in said wall on the side of said second side, and
• a separation cover resting on said second face and fixed to said wall so as to close said cavity and to delimit a first volume of the box in which a cooling fluid is intended to circulate with respect to a second volume of the box in which is intended to be positioned said electronic device, said separation cover comprising a heat sink intended to cool at least said electronic component of said electronic device, said heat sink comprising at least one fin, said at least one fin extending in said first volume.

Within the meaning of the invention, a fin is a projection extending on the underside of the main body and intended to increase the heat transmission surface between the main body and a cooling fluid in which the fin is immersed.

Thus, a fin can be a straight fin with constant section, a straight fin with variable section or a fin in the form of a conical stud, or even a fin of any shape.

Thanks to the invention, it is possible to produce the case and the heat sink separately. The separate production of these two elements makes it possible to optimize the manufacturing process of the heat sink by not taking into account during its manufacture the constraints linked to the size of the case. Thus, it is possible to obtain a cooling system after assembly of the case and the dissipator having for example thinner fins than in the prior art.

The cooling system according to the first aspect of the invention may also have one or more of the characteristics of the particular embodiments below, considered individually or in all technically possible combinations.

In a particular embodiment of the invention, the cavity is non-through. In other words, the cavity does not cross through the first face.

In a particular embodiment of the invention, the heat sink comprises a sole having a lower face and an upper face, said upper face being intended to receive heat to be dissipated emitted by said electronic component, said at least one fin s extending over an underside of the sole, said heat sink further comprising a part projecting laterally from said sole so as to be pressed against or bearing against said second face of said wall and fixed to said second face of said wall.

In a particular embodiment of the invention, the housing comprises a cooling fluid inlet, a cooling fluid outlet and a cooling circuit connecting said cooling fluid inlet to said cooling fluid outlet, said cooling circuit cooling being constituted at least in part by said first volume.

In a particular embodiment of the invention, the wall comprises a protuberance on the side of said first face and said cavity is also formed in said protuberance.

In a particular embodiment of the invention, the separation cover is fixed to said wall by friction stir welding.

In a particular embodiment of the invention, the housing and the separation cover are manufactured separately before being assembled.

In a particular embodiment of the invention, the housing is obtained by a first manufacturing process, for example by a foundry process, and the dissipator of the separation cover is obtained by a second manufacturing process, different from the first, for example by an extrusion process or else by a cold stamping process.

Thus, by using two different manufacturing processes, the case and the heatsink can be made of materials having different thermal conductivities, which improves the cooling performance of the cooling system according to the first aspect of the invention.

Thus, the aluminum used in foundry has a thermal conductivity of the order of 130 W m ⁻¹ ·K ⁻¹ while the aluminum used in extrusion has a thermal conductivity of the order of 200 W m ⁻¹ ·K ⁻¹ .

In a particular embodiment of the invention, the separation cover comprises a protuberance extending into said cavity, said first volume being delimited at least in part by said protuberance of said cover.

In a particular embodiment of the invention, the cover comprises a cavity, said cavity of said cover being formed in said protrusion of said cover and in a face of said cover facing said second volume.

In a particular embodiment of the invention, the sole comprises a hole and the cooling system further comprises a plate having two faces, said plate comprising a cavity on one face and a protuberance on the other face, said cavity of said plate being formed in said protuberance of said plate, said separation cover being produced by assembling said heat sink and said plate, the protuberance of said plate being inserted into the hole of said sole during assembly, the cavity of said plate forming the cavity of said cover and the protuberance of said plate forming the protuberance of said cover.

There is also proposed, according to a second aspect of the invention, an electronic system comprising an electronic component and a system for cooling this electronic component according to the first aspect of the invention.

Optionally, the electronic switch is a gallium nitride FET transistor or a MOSFET transistor (metal-oxide-semiconductor field-effect transistor) in silicon (Si-MOSFET) or silicon carbide ( SiC-MOSFET) or an IGBT transistor (insulated-gate bipolar transistor).

Optionally, the transistor is a HEMT (high-electron-mobility transistor) transistor, for example made of gallium nitride.

There is also proposed, according to a third aspect of the invention, an electric charger or a voltage converter comprising an electronic switch and a system for cooling this electronic switch according to the first aspect of the invention.

Optionally, the electronic switch is a gallium nitride FET transistor or a MOSFET transistor (metal-oxide-semiconductor field-effect transistor) in silicon (Si-MOSFET) or silicon carbide ( SiC-MOSFET) or an IGBT transistor (insulated-gate bipolar transistor).

Optionally, the transistor is a HEMT (high-electron-mobility transistor) transistor, for example made of gallium nitride.

There is also proposed, according to a fourth aspect of the invention, a method for manufacturing a cooling system for an electronic component of an electronic device according to the first aspect of the invention, this method comprising:

1. obtaining a casing comprising at least one wall, a first face of said wall being turned towards the outside of said casing and a second face of said wall being turned towards the inside of said casing, said casing comprising a cavity formed in said wall on the side of said second face,
2. obtaining a separation cover comprising a heat sink intended to cool at least said electronic component of said electronic device, said heat sink comprising at least one fin, and
3. fixing said separation cover to said wall so that said separation cover rests on said second face, so as to close said cavity and to delimit a first volume of the box in which a cooling fluid is intended to circulate relative to a second volume of the case in which said electronic device is intended to be positioned and so that said at least one fin extends into said first volume.

The invention will be better understood in the light of the following description, given solely by way of non-limiting example and referring to the following figures:

DESCRIPTION OF FIGURES

There is an exploded three-dimensional view of a voltage converter in a first embodiment of the invention.

There is a three-dimensional view of the upper part of a casing of a voltage converter in a first embodiment of the invention.

There is a three-dimensional view of a heat sink of a voltage converter in a first embodiment of the invention.

There is a three-dimensional view showing variants of fins of various shapes that can be obtained when an extrusion manufacturing process is used.

There is a block diagram illustrating the steps of a method of manufacturing a cooling system according to a first embodiment of the invention.

There is an exploded three-dimensional view of a voltage converter in a second embodiment of the invention.

There is a block diagram illustrating the steps of a method of manufacturing a cooling system according to a second embodiment of the invention.

DETAILED DESCRIPTION

In the following description, the elements will be identified in space with respect to an arbitrary bottom-top vertical direction (designated in the figures by the reference V), which may correspond to the usual vertical direction or to another direction depending the orientation of the system.

There is an exploded view in three dimensions of a voltage converter 1000' according to a first embodiment of the invention. The [Fig. 1] is an exploded view in three dimensions of such a voltage converter 1000'. The voltage converter 1000' includes an electronic device 400 and a cooling system 700'. The cooling system 700 'comprises a box 100 and a separation cover which is in the example described here a heat sink 200.

The electronic device 400 is in the example described here a DC/DC voltage converter called DC/DC voltage converter. This voltage converter is intended to be embedded in a vehicle in order to perform a voltage conversion between a first electrical network and a second electrical network of the vehicle. Typically, the first electrical network is a low voltage network delivering a voltage lower than 30V, for example approximately 24 or 12V, and the second electrical network is a high voltage network delivering a voltage greater than 30V, for example 48V.

In the example described here, the DC/DC voltage converter comprises an electronic card itself comprising a plurality of voltage choppers. Each of the voltage choppers comprises an inductor and two transistors, these two transistors being, in the example described here, gallium nitride (GaN) FET power transistors operating as electronic switches. As a variant, these transistors can also be MOSFET transistors or even IGBT transistors. The DC/DC voltage converter also comprises in the example described here, for each voltage chopper, a first safety transistor and a second safety transistor connected head to tail. In the example described here, the first safety transistor and the second safety transistor are MOSFETs.

By way of illustration are represented on the , the transistors T10, T20, T10' and T20' of the DC/DC voltage converter. The two transistors of the voltage choppers which are installed in the example described here on the opposite side of the electronic card to the side on which the safety transistors T10, T20, T10' and T20' are installed are not visible on the [ Fig. 1].

With reference to the and in [Fig. 2], the box 100 is hollow in shape and comprises in the example described here four side walls and a bottom wall constituting the bottom of this box 100 and connecting the side walls together. In the example described here, one of the four side walls includes an opening.

The lower wall comprises a first face 120 facing the outside of the box 100 and a second face 130 facing the inside of the box 100.

The box 100 further comprises a cavity 150 formed in the lower wall on the side of its second face 130.

The cavity 150 is also non-through, that is to say it does not cross the first face 120.

The separation cover or heat sink 200 rests on the second face 130 and is fixed to the lower wall so as to close the cavity 150 and to delimit a first volume of the box 100 in which a cooling fluid, for example a mixture of water and glycol, is intended to circulate relative to a second volume of the box 100 in which the electronic device 400 is intended to be positioned.

The housing 100 further comprises a cooling fluid inlet 190 and a cooling fluid outlet 190', the cooling fluid inlet 190 is connected to the cooling fluid outlet 190' by a cooling channel 140 formed at the less in part by the first volume. In other words, the cooling channel 140 is delimited at least in part by the cavity 150 closed by the separation cover.

With reference to the , the bottom wall comprises a protrusion 700 on the side of the first face 120, in which the cavity 150 is further formed.

In other words, the cooling channel 140 is less partially formed in the protuberance 700.

As shown on the , the cavity 150 is surrounded by an enclosure formed by a low wall 170 rising from the second face 130. The upper part of the low wall 170 consists of a flat surface.

The housing 100 further comprises a second cavity 650 formed in the lower wall on the side of its second face 130 and at least partially in the protuberance 700.

The second cavity 650 is also non-through and surrounded at least partially by the cavity 150.

In the example described here, the box 100 is produced by a first manufacturing process, for example a foundry process, that is to say using a mold into which a material under pressure is injected. This material has for example a thermal conductivity not exceeding 130 W/mK. It may for example be an aluminum alloy (such as AlSi9Cu3 or AlSi12(Fe)).

The heat sink 200 shown in comprises a sole 210 having an upper face intended to receive the heat to be dissipated emitted by the safety transistors T10', T20' and by the voltage converter transistors of the voltage converter as well as two groups of a plurality of fins 220, 220' extending over the underside of sole 210. Sole 210 also has a thickness substantially equal to the height of low wall 170.

The heat sink 200 is made of an aluminum alloy by the same casting process as that used to manufacture the case 100.

Indeed, in general, for the same manufacturing process, the thinness of the parts and their tolerance intervals are proportional to the largest dimension of the part. Thus, the heat sink 200 being smaller than the box 100, the same manufacturing process can make it possible to obtain finer and closer fins 220, 220'.

Alternatively, the heat sink 200 is made of aluminum (or an aluminum alloy) by an extrusion process or by a cold heading process.

The use of two different processes provides the following advantages. The second method of manufacture may be more economical than the first method of manufacture. In addition, it can make it possible to use, for the heat sink 200, a more economical and/or more thermally efficient material than the materials usable by the first manufacturing process. For example, when the heat sink 200 is obtained by extrusion, that is to say by pushing a paste of an aluminum alloy into a tube (or a die) to obtain a profile. An aluminum alloy having a thermal conductivity higher than 150 W/mK, for example reaching 200 W/mK, can be used.

In addition, the use of a second manufacturing process can make it possible to obtain fins having different geometries from those obtained by the first manufacturing process.

Thus, the shows, in the context of a second manufacturing process which would be a manufacturing process by extrusion, examples of fins of various shapes, for example in the shape of a fir tree, the branches of which are optionally inverted.

The dissipator 200 comprises a part 230 projecting laterally from the sole 210. In the example described here, the part 230 is in continuity of material with the sole 210 and projects laterally all around the sole 210. The part 230 is against and fixed on the second face 130 of the lower wall so as to close the cavity 150. Thus, by completely closing the cavity 150, the heat sink 200 delimits a first volume of the case 100 in which a cooling fluid is intended to circulate relative to a second volume of the box 100 in which the electronic device 400 is positioned.

In the example described here, the thickness of the sole 210 and of the part 230 are equal. As a variant, the thickness of the part 230 can be less than the thickness of the sole 210. The dimensions of the sole 210 and of the part 230 are such that the part 230 is flush with the low wall 170 and is surrounded by the latter. when the part 230 of the heat sink 200 is supported on the surface of the second face 130 located between the cavity 150 and the low wall 170. In addition, the part 230 has a thickness substantially equal to the height of the low wall 170, the upper part of the wall 170 and the upper face of the part 230 are thus substantially coplanar. In the example described here, part 230 and wall 170 are welded by friction stir.

The sole 210 further comprises two low walls 250, 251 which in the example described are of the same height and whose upper parts are flat.

In addition, the two walls 250 and 251 extend straight from the upper face of the dissipator 200 in a direction substantially equal to the direction of the plurality of fins 220.

The sole 210 also includes two other low walls 250', 251' which in the example described are of the same height and whose upper parts are flat.

In addition, the two walls 250' and 251' extend straight from the upper face of the dissipator 200 in a direction substantially equal to the direction of the plurality of fins 220'.

In addition, the heights of the walls 250, 251, 250', 251' are substantially equal so that the upper parts of these four walls are substantially coplanar.

The upper parts of the walls 250, 251 are in thermal contact, possibly via at least one thermal tab, with one or more electronic components to be cooled of the electronic device 400. In the example described here, the upper parts of the low walls 250, 251 are in thermal contact with the safety transistors T10', T20' via a thermal tab and the electronic card bearing these transistors.

The upper parts of the walls 250', 251' are in thermal contact, possibly via at least one thermal leg, with one or more electronic components to be cooled of the electronic device 400. In the example described here, the parts high walls 250', 251' are in thermal contact with the safety transistors T10, T20 by means of a thermal tab and the electronic card carrying these transistors.

On the other hand, the upper face of the sole 210 is also in thermal contact, for example via a thermal leg, with transistors of the voltage choppers of the electronic device 400.

In addition, the sole 210 includes a hole 285 located between the two groups of low walls 250, 251 and 250', 251' so that the electronic components of the electronic device 400 can pass through the sole 210 in order to be housed at least partially in the second cavity 650 of case 100. In the example described here, inductors of the voltage choppers of electronic device 400 are thus at least partially housed in cavity 650.

The second face 130 of the box 100 further comprises positioning elements (not shown in the figures) of the electronic card intended to position it on the second face 130 in a predetermined position. For example, the positioning elements can consist of two lugs projecting perpendicular to the bottom wall. These positioning elements are intended to cooperate with complementary positioning elements of the electronic card to position the electronic card vis-à-vis the lower wall. For example, the complementary positioning elements can be through holes made in the electronic card and intended to cooperate with the lugs.

The second face 130 further comprises means for supporting the electronic device 400. For example, the support means comprise at least one screw barrel 600. In the example described here, the second face 130 comprises five screw barrels on which the electronic card of the electronic device 400 is placed before being screwed.

The upper part of the screw barrels is higher than the upper part of the low wall 170 so that when assembling the electronic device 400 on the support means of the case 100, the transistors T10, T10', T20 and T20' of the device electronics 400 can be in thermal contact, possibly via a thermal leg, with the low walls 250, 251, 250', 251' of the heat sink 200.

With reference to the , a method 900 of manufacturing the cooling system of [FIG. 1] will now be described.

During a step 910, the case 100 is obtained, for example by a foundry process.

During a step 911, the heat sink 200 is obtained, for example by an extrusion manufacturing process.

During a step 920, the separation cover 200 is fixed to the lower wall so that the separation cover 200 bears against the second face 130, so as to close the cavity 150 and to delimit a first volume of the housing 100 in which a cooling fluid is intended to circulate relative to a second volume of the housing 100 in which said electronic device is intended to be positioned and so that the plurality of fins 220, 220' extend in the first volume

For this purpose, the part 230 of the dissipator 200 is pressed against and bears against the second face 130 of the lower wall. Once positioned on the second face 130 of the lower wall, the part 230 and the low wall 170 are welded by friction mixing.

We will now describe with reference to the a voltage converter 1000'' according to a second embodiment of the invention. The [Fig. 6] is an exploded view in three dimensions of such a voltage converter 1000''. The voltage converter 1000'' comprises an electronic device 400' (not shown in the figure) and a cooling system 700''. The cooling system 700'' comprises a box 100' and a separation cover 8000, the separation cover 8000 and the box 100' having moreover been manufactured independently.

The electronic device 400′ is in the example described here a DC/DC voltage converter called a DC/DC voltage converter. This voltage converter is intended to be embedded in a vehicle in order to perform a voltage conversion between a first electrical network and a second electrical network of the vehicle. Typically, the first electrical network is a low voltage network delivering a voltage lower than 30V, for example approximately 24 or 12V, and the second electrical network is a high voltage network delivering a voltage greater than 30V, for example 48V.

In the example described here, the DC/DC voltage converter comprises an electronic card itself comprising a plurality of voltage choppers. Each of the voltage choppers comprises an inductor and two transistors, these two transistors being, in the example described here, gallium nitride (GaN) FET power transistors operating as electronic switches. As a variant, these transistors can also be MOSFET transistors or even IGBT transistors.

The DC/DC voltage converter also comprises in the example described here, for each voltage chopper, a first safety transistor and a second safety transistor connected head to tail. In the example described here, the first safety transistor and the second safety transistor are MOSFETs.

The box 100' is hollow in shape and comprises in the example described here four side walls (not shown in the figure) and a bottom wall constituting the bottom of this box 100' and connecting the side walls together.

The lower wall comprises a first face facing the outside of the box 100' and a second face 1300 facing the inside of the box 100'.

The box 100' further comprises a cavity 1500 formed in the lower wall on the side of its second face 1300.

The separation cover 8000 bears against the second face 1300 and is fixed to the lower wall so as to close the cavity 1500 and to delimit a first volume of the box 100' in which a cooling fluid, for example a mixture of water and glycol, is intended to circulate relative to a second volume of the box 100' in which the electronic device 400' is intended to be positioned.

The housing 100′ further comprises a cooling fluid inlet 1900 and a cooling fluid outlet 1900′, the cooling fluid inlet 1900 is connected to the cooling fluid outlet 1900′ by a cooling channel formed at the less in part by the first volume. In other words, the cooling channel is delimited at least in part by the cavity 1500 closed by the separation cover 8000.

The wall 1100 includes a protuberance 7000 on the side of the first face, in which the cavity 1500 is also formed. The cavity 1500 is also non-through.

In other words, the cooling channel is less partially formed in the protrusion 7000.

The cavity 1500 is surrounded by an enclosure formed by a low wall 1700 rising from the second face 1300. The upper part of the low wall 1700 consists of a flat surface.

In the example described here, the box 100′ is produced by a first manufacturing process, for example a foundry process, that is to say using a mold into which a material under pressure is injected. This material has for example a thermal conductivity not exceeding 130 W/mK. It may for example be an aluminum alloy (such as AlSi9Cu3 or AlSi12(Fe)).

The 8000 splitter hood includes a 2000 heat sink and a 3000 plate.

The heat sink 2000 comprises a base 2100 having an upper face intended to receive the heat to be dissipated emitted by electronic components of the electronic device 400' (in the example described here, by the transistors of the DC/DC voltage converter) and two groups of a plurality of fins 2200, 2200' extending over the underside of the sole 2100. The sole 2100 also has a thickness substantially equal to the height of the low wall 1700.

The upper face of the sole 2100 is in thermal contact, for example via a thermal tab, with transistors of the voltage choppers of the electronic device 400.

Furthermore, the sole 2100 includes a hole 2850 located between the two groups of plurality of fins 2200, 2200'.

Plate 3000 has two sides. On the first face, the plate 3000 comprises a cavity 3100 and on the second face, the plate 3000 comprises a protuberance 3200, the cavity 3100 being non-through and formed in the protuberance 3200.

During assembly of the separation cover 8000, the protuberance 3200 of the plate 3000 is inserted into the hole 2850 of the sole 2100, then the plate 3000 is fixed to the sole 2100 for example by a friction kneading process.

Thus, once assembled, the separation cover 8000 comprises a protuberance 3200 and a non-through cavity 3100 formed in this protrusion 3200.

Thus, the electronic components of the electronic device 400′ can be housed at least partially in the cavity 3100 of the separation cover 8000 and thus be cooled by the cooling system 700′. In the example described here, the inductances of the voltage choppers of the electronic device 400′ are thus at least partially housed in the cavity 3100.

Furthermore, when the separation cover 8000 is fixed to the lower wall of the box 100', the protuberance 3200 extends into the cavity 1500 and the first volume is delimited at least in part by the protuberance 3200. In other words , the cooling channel is at least partly delimited by the protrusion 3200, the sole 2100 of the heat sink 2000 and the cavity 1500.

The 2000 heat sink is made of an aluminum alloy by the same foundry process as that used to manufacture the 100' case.

Indeed, in general, for the same manufacturing process, the thinness of the parts and their tolerance intervals are proportional to the largest dimension of the part. Thus, the heat sink 2000 being smaller than the box 100', the same manufacturing process can make it possible to obtain finer and closer fins 2200, 2200'.

Alternatively, the heat sink 2000 is made of aluminum (or an aluminum alloy) by an extrusion process or by a cold heading process.

The use of two different processes provides the following advantages. The second method of manufacture may be more economical than the first method of manufacture. In addition, it can make it possible to use, for the heat sink 2000, a material that is more economical and/or more thermally efficient than the materials that can be used by the first manufacturing process. For example, when the heat sink 2000 is obtained by extrusion, that is to say by pushing a paste of an aluminum alloy in a tube (or a die) to obtain a profile. An aluminum alloy having a thermal conductivity higher than 150 W/mK, for example reaching 200 W/mK, can be used.

In addition, the use of a second manufacturing process can make it possible to obtain fins having different geometries than those obtained by the first manufacturing process.

Furthermore, the dissipator 2000 comprises a part 2300 projecting laterally from the sole 2100. In the example described here, the part 2300 projects laterally all around the sole 2100. The part 2300 is pressed against and fixed on the second face 1300 of the lower wall so as to close the cavity 1500. Thus, by completely closing the cavity 1500, the separation cover 8000 delimits a first volume of the box 100 'in which a cooling fluid is intended to circulate with respect to a second volume of the box 100' in which the electronic device 400' is positioned.

In the example described here, the thickness of the sole 2100 and the part 2300 are equal. Alternatively, the thickness of the part 2300 may be less than the thickness of the sole 2100. The dimensions of the sole 2100 and of the part 2300 are such that the part 2300 is flush with the low wall 1700 and is surrounded by it. when the part 2300 of the heat sink 2000 is supported on the surface of the second face 1300 located between the cavity 1500 and the wall 1700. In addition, the part 2300 has a thickness substantially equal to the height of the wall 1700, the upper part of the low wall 1700 and the upper face of the part 2300 are thus substantially coplanar.

The second face 1300 of the box 1000 can further comprise positioning elements (not shown in the figures) of the electronic card intended to position it on the second face 1300 in a predetermined position. For example, the positioning elements may consist of lugs projecting perpendicular to the bottom wall. These positioning elements are intended to cooperate with complementary positioning elements of the electronic card to position the electronic card vis-à-vis the lower wall. In the aforementioned example of the lugs, these complementary positioning elements are for example through holes made in the electronic card.

The second face 1300 further comprises means for supporting the electronic device 4000. For example, the support means comprise for example at least one screw barrel on which the electronic card of the electronic device 4000 is placed before being screwed.

With reference to the , a method 9000 of manufacturing the cooling system of [Fig 6] will now be described.

During a step 9100, the box 100′ is obtained, for example by a foundry process.

During a step 9110, the heat sink 2000 is obtained, for example by an extrusion manufacturing process.

During a step 9120, the plate 3000 is obtained, for example by a manufacturing process by stamping.

During a step 9130, the plate 3000 and the heat sink 2000 are assembled. During this step, the protrusion 3200 of the plate 3000 is inserted into the hole 2850 of the sole 2100 so that the plate 3000 is pressed against the sole 2100 of the heat sink 2000, then the plate 3000 and the heat sink 2000 are fixed for example by a friction kneading process.

During a step 9200, the part 2300 of the heat sink 2000 is attached to the bottom wall 1100 so as to close the opening 1500 and so that the plurality of fins 2200 and 2200' extend into the first volume.

For this purpose, the part 2300 of the sole 2100 of the dissipator 2000 is pressed against and bears against the second face 1300 of the lower wall. Once positioned on the second face 1300 of the lower wall 1100, the part 2300 and the upper part of the low wall 1700 are welded by friction mixing.

The present invention is not limited to the embodiments previously described. It will indeed be apparent to those skilled in the art that modifications can be made thereto.

For example, in the previously described embodiments the coolant may be air, water, oil or liquid nitrogen instead of a mixture of water and glycol.

For example, in an alternative embodiment to that described in relation to the in [Fig.5], the electronic device 400 could be an electric charger, for example an on-board charger in a motor vehicle.

Similarly, in an alternative embodiment to that described in relation to the in [Fig.7], the electronic device 400 could be an electric charger, for example an on-board charger in a motor vehicle.

Furthermore, in an alternative embodiment to that described in relation to the to [Fig. 5], the fins of the heat sink 200 could be replaced by a plurality of fins having the shape of a conical pad occupying substantially the same surface on the underside of this sink.

Similarly, in an alternative embodiment to that described in relation to the to [Fig. 7], the fins of the heat sink 2000 could be replaced by a plurality of fins having the shape of a conical stud occupying substantially the same surface on the underside of this sink.

Furthermore, the terms used in the claims should not be interpreted as being limited to the elements of the embodiments previously described, but should on the contrary be interpreted as including all equivalent elements the provision of which is within the reach of those skilled in the art. applying general knowledge.

Claims (11)

System for cooling (700', 700'') an electronic component (T10) of an electronic device (400, 400') comprising

1. a box (100, 100') comprising at least one wall, a first face of said wall being turned towards the outside of said box (100, 100') and a second face (130, 1300) of said wall being turned towards the 'inside said box (100, 100'), said box (100, 100') comprising a cavity (150, 1500) formed in said wall on the side of said second face (130, 1300), and
2. a separation cover (200, 8000) resting on said second face (130, 1300) and fixed to said wall so as to close said cavity (150, 1500) and to delimit a first volume of the box (100, 100') in which a cooling fluid is intended to circulate with respect to a second volume of the case (100, 100') in which said electronic device (400) is intended to be positioned, said separation cover (200, 8000) comprising a dissipator (200, 2000) intended to cool at least said electronic component (T10) of said electronic device (400), said heat sink (200, 2000) comprising at least one fin (220, 2200), said at least one fin (220 , 2200) extending into said first volume.

Cooling system (700', 700'') according to the preceding claim, in which the said heat sink (200, 2000) comprises a sole (210, 2100) having a lower face and an upper face, the said upper face being intended to receive the heat to be dissipated emitted by said electronic component (T10), said at least one fin (220, 2200) extending on an underside of the sole (210, 2100), and in which said heat sink (200, 2000) further comprises a part (230, 2300) projecting laterally from said sole (210, 2100) so as to be pressed against said second face (130, 1300) of said wall and fixed to said second face (130, 1300 ) of said wall. Cooling system (700', 700'') according to one of the preceding claims, in which the said housing (100, 100') comprises a cooling fluid inlet (190, 1900), an outlet (190', 1900') in cooling fluid and a cooling circuit connecting said cooling fluid inlet (190, 1900) to said cooling fluid outlet (190', 1900'), said cooling circuit being constituted at least in part by said first volume . Cooling system (700', 700'') according to one of the preceding claims, in which said wall comprises a protrusion (700, 7000) on the side of said first face and in which said cavity (150, 1500) is further formed in said protuberance (700,7000). Cooling system according to one of the preceding claims, in which the separation cover is fixed to the said wall by friction stir welding. Cooling system according to one of the preceding claims, in which the casing is obtained by a first manufacturing process, for example by a foundry process, and in which the dissipator of the separation cover is obtained by a second manufacturing process, different of the first, for example by an extrusion process or else by a cold stamping process. Cooling system (700'') according to one of Claims 1 to 6, in which the said separation cover (2000) comprises a protuberance extending into the said cavity (1500), the said first volume being delimited at least in part by the said protuberance of said cover (2000). Cooling system (700'') according to claim 7 wherein said cover (2000) comprises a cavity, said cavity of said cover being formed in said protuberance of said cover and in a face of said cover facing said second volume. A cooling system (700'') according to claim 8 and claim 2 wherein said sole includes a hole, said cooling system further comprising a plate having two sides, said plate comprising a cavity on one side and a protrusion on the other face, said cavity of said plate being formed in said protuberance of said plate, said separation cover being produced by assembling said heat sink and said plate, the protuberance of said plate being inserted into the hole of said sole during assembly, the cavity of said plate forming the cavity of said cover and the protuberance of said plate forming the protuberance of said cover. Electric charger or voltage converter comprising an electronic switch and a system for cooling said electronic switch according to one of Claims 1 to 9. Method of manufacturing (500, 900) a cooling system (700, 700') for an electronic component (T10) of an electronic device (400) according to any one of Claims 1 to 9, comprising:

1. obtaining (510, 910) a box (100, 100') comprising at least one wall, a first face of said wall facing the outside of said box (100, 100') and a second face (130 , 1300) of said wall facing the inside of said box (100, 100'), said box (100, 100') comprising a cavity (150, 1500) formed in said wall on the side of said second face (130, 1300),
2. obtaining (511, 911) a separation cover (200, 8000) comprising a heat sink (200, 2000) intended to cool at least said electronic component (T10) of said electronic device (400), said heat sink (200, 2000) comprising at least one fin (220, 2200), and
3. fixing (520, 920) said separation cover (200, 8000) to said at least one wall so that said separation cover rests on said second face, so as to close said cavity (150, 1500) and to delimit a first volume of the case (100, 100') in which a cooling fluid is intended to circulate relative to a second volume of the case (100, 100') in which the said electronic device (400) is intended to be positioned and so that said at least one fin extends into said first volume.