Electronic apparatus casing having radiator and fan

Abstract

An electronic apparatus casing (1) comprising an electronic board bearing heat dissipation elements (51, 52) to be cooled, said casing comprising: - a rigid frame (4); - a rigid cover (6) attached to the frame in order to form a housing; - a radiator (3) placed above said electronic board received in the housing, said radiator comprising a bottom wall (35) in thermal contact with the heat dissipation elements; - said radiator (3) comprising a plurality of cooling fins (36) extending vertically in a first portion (3A) of the bottom wall and a plurality of pins (37) extending vertically in a second portion (3B) of the bottom wall; - a blower fan (2) positioned on said plurality of pins so as to raise said fan off the bottom wall of the radiator in order to create an air passage through the pins.

Description

Description Title: Electronic device case with a radiator and a fan Technical field

[0001] The present disclosure relates to the field of cooling electronic components in an electronic device housing. More particularly, the subject matter of the disclosure is electronic device housings comprising a radiator and a fan intended to cool one or more electronic components arranged in the housing. Prior art

[0002] In the automotive industry, increasingly powerful electronic components are being used, particularly due to the development of new features such as driver assistance or autonomous driving, for example. These electronic components heat up when in operation. It is necessary to provide means to ensure the dissipation of this heat.

[0003] Generally, the electronic enclosure includes a rigid chassis, a rigid cover, an electronic board, electronic components mounted on the board, heat dissipation elements, a radiator and a blower fan.

[0004] The rigid cover is fixed to the chassis to form a housing. The cover and the chassis define a housing space in which the electronic card carrying the components is received.

[0005] The electronic components are mounted flat on the circuit board, i.e. their largest dimension is substantially parallel to the housing.

[0006] Electronic components that are heat generating sources are provided with heat dissipation elements to ensure the dissipation of this heat.

[0007] The heat sink, formed from a material having good thermal conductivity, is disposed flat within the housing, with one side of the bottom wall in thermal contact with the heat sink elements to assist in dissipating heat. The bottom wall of the heat sink is divided into two regions. A first region includes a plurality of fins extending vertically from the bottom wall and a second region includes a smooth, flat surface.

[0008] The fan is a blower fan. It consists of a stator structure, a motor, and a rotor with blades. The stator structure includes two main faces, opposite and parallel, and a side wall connecting the two faces. The fan has two air inlets located on either side of the rotor made in the two main faces and a single air outlet on the side wall facing the fins when the fan is mounted in the radiator. During operation, the air flow set in motion by the fan blades is an air flow that enters the two air inlets and then blows through the air outlet towards the cooling fins. For space reasons, the blower fan is mounted flat on the smooth part of the radiator, i.e. their largest dimension is substantially parallel to the electronic plate.In other words, the fan is mounted on the smooth part of the radiator with the rotation axis of the fan rotor perpendicular to the smooth, flat surface of the radiator bottom wall.

[0009] The arrangement of the fan in relation to the radiator does not allow for efficient cooling of all the elements located under the radiator. Indeed, since one of the fan's air inlets is pressed against the smooth part of the radiator, the dissipation element located under the smooth part does not directly benefit from a forced airflow like the other element located under the area with the fins that generate a forced airflow. The heat dissipated by the element located under the fan is transferred by the bottom wall of the radiator to the area with the fins and located above the second element. In addition, since one of the two fan air inlets is obstructed in this assembly by the smooth part, this configuration also reduces the performance of the airflow generated by the fan blades. Statement of the invention

[0010] The present invention aims to partially overcome these drawbacks by proposing a solution compatible with all these problems. The present invention aims to ensure the efficient cooling of all the dissipative elements, while limiting production costs and guaranteeing a restricted occupation volume so as not to disrupt its integration into applications, in particular applications in the automotive field.

[0011] To this end, the invention relates to an electronic device housing comprising an electronic card carrying at least one heat dissipation element to be cooled, said housing comprising: - a rigid chassis; - a rigid cover configured to be fixed on the chassis to form an open housing in which said electronic card is received; - a radiator intended to cool said at least one heat dissipation element, said radiator being received in said open housing and placed above said electronic card, said radiator comprising a bottom wall having a lower face oriented towards the inside of the housing and an upper face oriented towards the outside of the housing, the lower face of said bottom wall being in thermal contact with an upper face of said at least one heat dissipation element; - said radiator comprising a plurality of cooling fins extending vertically in a first part of the radiator from said upper face of the bottom wall and a plurality of pins extending vertically in a second part of the radiator from said upper face of the bottom wall; - a blower fan positioned on said plurality of pins so as to raise said fan relative to the bottom wall of the radiator to create an air passage through the pins between the fan and the bottom wall.

[0012] The features set out in the following paragraphs may, optionally, be implemented, independently of each other or in combination with each other:

[0013] According to one embodiment, the blower fan comprises a rotor with blades, two air inlets located on either side of the rotor and an air outlet configured to generate an air flow towards the cooling fins of the radiator, the fan being arranged in the second part of the radiator with the axis of rotation (Z1) of the rotor perpendicular to the bottom wall of the radiator.

[0014] According to another embodiment, the pins are arranged on the second part of the bottom wall of the radiator so as to form an air space between a lower main face of the fan and an upper face of the bottom wall of the radiator adapted to allow air circulation.

[0015] Advantageously, the spikes are arranged on the second part of the bottom wall so as to create air circulation to optimize the collection of calories while limiting pressure loss.

[0016] According to one embodiment, the spikes have a height of between 1 mm and 30 mm, preferably between 6 mm and 12 mm.

[0017] According to one embodiment, the housing further comprises a thermal interface layer placed between the lower face of the bottom wall of the radiator and the upper face of each dissipation element to ensure thermal contact.

[0018] According to another embodiment, the radiator comprises two longitudinal side walls, a transverse side wall and two lateral extensions which form a base with the bottom wall, said base being configured to be fixed to the chassis in order to form the electronic box with the chassis and the cover.

[0019] Preferably, said at least one heat dissipation element comprises a first heat dissipation element located under the cooling fins and a second heat dissipation element located under the pins.

[0020] According to one embodiment, the radiator and the frame form a single piece.

[0021] Preferably, the radiator is made of thermally conductive material. Brief description of the drawings

[0022] Other characteristics, details and advantages of the invention will appear on reading the detailed description below, and on analyzing the attached drawings, in which: Fig. 1

[0023] [Fig. 1] Figure 1 schematically illustrates an exploded perspective view of an electronic device housing comprising a fan and a radiator according to one embodiment. Fig. 2

[0024] [Fig. 2] Figure 2 schematically illustrates a perspective view of the housing of Figure 1 in an assembled state. Fig. 3

[0025] [Fig. 3] Figure 3 schematically illustrates a top view of the housing of Figure 1 in an assembled condition. Fig. 4

[0026] [Fig. 4] Figure 4 schematically illustrates a sectional view along axis AA of the housing of Figure 3. Fig. 5

[0027] [Fig. 5] Figure 5 schematically illustrates a sectional view along axis BB of the housing of Figure 3. Description of the embodiments

[0028] The drawings and the description below contain, for the most part, elements of a certain character. They may therefore not only serve to better understand the present invention, but also contribute to its definition, if necessary.

[0029] Reference is now made to Figures 1 to 5 which illustrate an electronic device housing 1 according to an embodiment of the invention, arranged in an orthonormal XYZ reference frame.

[0030] The electronic device housing 1 may be, for example, an electronic unit mounted on board a vehicle comprising one or more electronic components. In the context of the present invention, a forced air flow is generated outside the housing, along one of the walls of the housing to promote the cooling of certain electronic components contained in the housing.

[0031] The electronic box 1 comprises a rigid chassis 4, a rigid cover 6, an electronic card 5 on which are mounted two heat dissipation elements 51, 52 provided to allow the dissipation of the heat generated by the electronic components contained in the box 1, a radiator 3 positioned on the two heat dissipation elements 51, 52 and a blower fan 2 to generate the forced air flow.

[0032] In the example illustrated in Figure 2 which represents the housing in an assembled state, the housing 1 has a rectangular parallelepiped shape. It comprises an upper facade with the fan 2 and the cooling fins 36 of the radiator 3 which are visible. The upper facade extends in a horizontal plane XY. The height of the housing 1 extends in the Z direction.

[0033] The cover 6 comprises a bottom wall 61 having a substantially rectangular shape. The chassis 4 comprises a frame comprising a peripheral edge 43 having a substantially rectangular shape and two parallel and opposite side walls 41, 42 extending vertically in the Z direction from the peripheral edge 43. The cover 6 is configured to be fixed to the chassis 4 and to the electronic card 5 so as to hold the electronic card 5 in the housing. Thus, the side walls 41, 42 of the chassis 4 and the bottom wall 61 of the cover 6 delimit an open housing 9 in which the electronic card 5 is received. By way of example, the cover 6 and the electronic card 5 comprise a plurality of fixing holes intended to receive screws making it possible to fix the electronic card 5 and the cover 6 to the chassis 4.

[0034] The chassis 4 and the cover 6 are both rigid in order to guarantee good integrity of the electronic card 5 and the electronic components. The chassis 4 and the cover 6 are for example molded parts.

[0035] The card 5 comprises a plate 53 which extends in an XY plane and heat dissipation elements 51, 52 mounted flat in the housing, i.e. their largest dimension is substantially parallel to the housing.

[0036] The heat dissipation elements 51, 52 are formed from a material having good thermal conductivity and are provided on the electronic components which are also mounted flat on the electronic card.

[0037] The radiator 3 described here is made of thermally conductive material and configured to be in thermal contact with the heat dissipation elements 51, 52 when it is received in the open housing 9 and positioned on the heat dissipation elements 51, 52. For example, it is made of aluminum, magnesium or thermally conductive plastic. Thus, the heat dissipation elements 51, 52 allow the dissipation of the heat generated by the components towards the radiator.

[0038] The radiator 3 is configured to be fixed to the chassis 4 by any suitable means, by screwing, riveting or welding for example, in order to ensure good rigidity to the chassis / radiator assembly.

[0039] The radiator 3 comprises a bottom wall 35 which extends in the XY plane, parallel to the electronic card 5, two longitudinal side walls 31, 34, parallel and opposite which extend in an XZ plane from the two long sides of the bottom wall. The radiator 3 also comprises a transverse side wall 32 which extends in a YZ plane from one of the two short sides of the bottom wall. Thus, the longitudinal side walls 31, 34 and the transverse side wall 32 surround the three sides of the bottom wall 35 of the radiator, leaving one side of the bottom wall open. The lower edges of the two short sides of the bottom wall 35 protrude beyond the lower face of the bottom wall 35, respectively forming two extensions 32E, 33 which are intended to bear against the peripheral edge 43 of the chassis 4 when the radiator 3 is positioned on the heat dissipation elements 51, 52.In other words, the bottom wall 35, the longitudinal side walls 31, 34, the transverse side wall 32 and the two lateral extensions 32E, 33 form a base having a rectangular parallelepiped shape whose dimension is adjusted so that when it is received in the open housing 9 formed by the cover 6 and the chassis 3,. and placed above the electronic card 5, the side walls 31, 34 of the radiator are in edge-to-edge contact respectively with the edges 44, 45 of the corresponding side walls 42, 41 of the chassis 4, as illustrated in FIG. 4. The lower face of the bottom wall 35 of the radiator 3 is in thermal contact with the heat dissipation elements 51, 52. The two extensions 32E, 33 bear against the peripheral edge 43 of the chassis 4. Thus, when the radiator 3 is placed in the open housing 9 of the housing, its bottom wall 35, its longitudinal side walls 31, 34, its transverse side wall 32 and the two lateral extensions 32E, 33 form a cover which closes the open housing 9 formed by the chassis 4 and the cover 6.

[0040] According to one exemplary embodiment, the chassis 4 and the radiator 3 are two separate parts. According to another exemplary embodiment, the chassis 4 and the radiator 3 form a single part.

[0041] According to an exemplary embodiment, the housing 1 further comprises an interface layer made of a thermally conductive material 38, 39 placed between the lower face of the bottom wall 35 of the radiator 3 and the upper face of each dissipation element 51, 52 to ensure thermal contact.

[0042] Figures 4 and 5 illustrate in more detail the configuration of the radiator 3 according to two different section views.

[0043] The radiator is divided into two parts 3A, 3B by a central wall 7 oriented parallel to the transverse side wall 32 of the radiator. The first part 3A comprises a plurality of cooling fins 36 which extend vertically from the bottom wall 35, and oriented parallel to the longitudinal side walls 31, 34 as illustrated in FIG. 2. The fins 36 extend in the X direction from the central wall 7 to the open side of the radiator 3. The second part 3B comprises a plurality of pins 37 which extend vertically from the bottom wall in the Z direction.

[0044] The housing 1 comprises a first heat dissipation element 51 located under the cooling fins 36, in thermal contact with a lower face of the bottom wall 35 of the first part 3A of the radiator and a second heat dissipation element 52 located under the pins 37, in thermal contact with a lower face of the bottom wall 35 of the second part 3B of the radiator.

[0045] In order to enhance the dissipation of heat emitted by the electronic components, a forced airflow circulating outside the housing is generated by the fan 2 which is a blower fan in the case of the present disclosure.

[0046] As illustrated in Figures 2 and 3, the fan 2 comprises a stator structure, a motor and a rotor 21 with blades 22. In the case illustrated in the present application, the blades 22 are visible as in known solutions. The stator structure comprises an upper main face 25 and a lower main face 28 which extend in the XY plane parallel to the bottom wall of the radiator, and a side wall 26 which joins the two faces on a part so as to form a lateral opening 27. The fan 2 further comprises an annular opening 23 on the upper 25 and lower 28 faces. Only the annular opening 23 of the upper face is visible in Figures 1 to 3. The two annular openings 23 form two air inlets located on either side of the rotor 21 and the lateral opening 27 forms an air outlet.

[0047] The fan 2 is fixed securely to the radiator 3, by any suitable means, for example by gluing with double-sided adhesive.

[0048] The fan 2 is mounted flat in the second part 3B of the radiator, with the axis of rotation (Z1) of the rotor perpendicular to the bottom wall of the radiator 3. The fan 2, unlike the prior art described in the introductory part, is positioned on the plurality of pins 37 so that the fan is raised relative to the bottom wall 35 of the radiator 3 to create an air passage 8 between the fan 2 and the bottom wall 35 of the radiator. Thus, the air inlet of the lower face 28 formed by the annular opening 23 is no longer applied against the bottom wall 35 and is no longer obstructed by the bottom wall of the radiator while allowing flat mounting of the fan in the radiator to maintain the compactness of the housing.

[0049] The pins 37 are arranged relative to each other so as to form a space 8 adapted to allow air to circulate under the fan 2, between the lower main face 28 of the fan 2 and the upper face of the wall bottom 35 of the radiator. The arrangement of the pins 37 also allows the air to be mixed to optimize the collection of calories while limiting the pressure loss. In addition, the pins 37 are configured to provide a mechanical support surface to support the fan.

[0050] According to one exemplary embodiment, the pins 37 of the radiator are arranged at regular intervals so as to form a network of pins. According to another exemplary embodiment, they are distributed randomly on the bottom wall of the radiator.

[0051] They extend vertically from the bottom wall 35 in the Z direction and have a height of between 1 mm and 30 mm, preferably between 6 mm and 12 mm.

[0052] The fan 2 is arranged in the second part 3B of the radiator 3 so that the air outlet 27 is oriented towards the cooling fins 36. The air flow set in motion by the blades of the fan 2 therefore enters through the two air inlets 23 and exits through the air outlet 27 towards the cooling fins 36.

[0053] The presence of the pins 37 makes it possible to improve the heat collection performance conducted by the pins. Indeed, the air inlet of the lower surface 28 formed by the annular opening 23 is no longer obstructed in the flat mounting of the fan in the radiator. In addition, the second heat dissipation element 52 which is located under the pins 37 can benefit from forced convection like the first dissipation element 51 located under the fins 36 due to the passage of air created through the pins in the formed space 8.

[0054] It should also be noted that the presence of the pins 37 does not change the number of parts to be assembled, nor the mounting of the fan in the housing to keep the housing compact. This therefore maintains the number of parts to be stored and therefore the costs related to the storage and assembly of the electronic device housing. Industrial application

[0055] The electronic box according to the invention is particularly suitable for equipping electronic units on board a motor vehicle which must be ventilated by an air flow to cool certain components.

[0056] This disclosure is not limited to the example of an electronic device housing described above but it encompasses all the variants that a person skilled in the art may envisage within the framework of the protection sought.

Claims

Claims

1. Electronic device housing (1) comprising an electronic card (5) carrying at least one heat dissipation element (51, 52) to be cooled, said housing comprising: - a rigid chassis (4); - a rigid cover (6) configured to be fixed on the chassis to form an open housing in which said electronic card is received; - a radiator (3) intended to cool said at least one heat dissipation element, said radiator being received in said open housing and placed above said electronic card, said radiator comprising a bottom wall (35) having a lower face oriented towards the inside of the housing and an upper face oriented towards the outside of the housing, the lower face of said bottom wall being in thermal contact with an upper face of said at least one heat dissipation element; - said radiator (3) comprising a plurality of cooling fins (36) extending vertically in a first part (3A) of the radiator from said upper face of the bottom wall and a plurality of pins (37) extending vertically in a second part (3B) of the radiator from said upper face of the bottom wall; - a blower fan (2) positioned on said plurality of pins (37) so as to raise said fan (2) relative to the bottom wall (35) of the radiator to create an air passage (8) through the pins (37) between the fan and the bottom wall; - said spikes (37) being arranged on the second part (3B) of the bottom wall so as to create air circulation to optimize the collection of calories while limiting the pressure loss.

2. Housing according to claim 1, in which the blower fan (2) comprises a rotor (21) with blades (22), two air inlets (23) located on either side of the rotor and an air outlet (27) configured to generate an air flow towards the cooling fins (36) of the radiator, the fan being arranged in the second part (3B) of the radiator with the axis of rotation (Z1) of the rotor perpendicular to the bottom wall of the radiator.

3. Housing according to claim 1 or 2, wherein the pins (37) are arranged on the second part (3B) of the bottom wall (35) of the radiator so as to form an air space (8) between a lower main face (28) of the fan and an upper face of the bottom wall (35) of the radiator (3) adapted to allow the circulation of air.

4. Housing according to one of claims 1 to 3, in which the pins (37) have a height of between 1 mm and 30 mm, preferably between 6 mm and 12 mm.

5. Housing according to one of claims 1 to 54, further comprising a thermal interface layer (38, 39) placed between the lower face of the bottom wall (35) of the radiator and the upper face of each dissipation element (51, 52) to ensure thermal contact.

6. Housing according to one of claims 1 to 65, in which the radiator (3) further comprises two longitudinal side walls (31, 34), a transverse side wall (32) and two lateral extensions (33, 32E) which form with the bottom wall (35) a base, said base being configured to be fixed on the chassis (4) in order to form with the chassis (4) and the cover (6) the electronic housing.

7. Housing according to one of claims 1 to 6, wherein said at least one heat dissipation element comprises a first heat dissipation element (51) located under the cooling fins (36) and a second heat dissipation element (52) located under the pins (37).

8. Housing according to one of claims 1 to 7, in which the radiator (3) and the chassis (4) form a single piece.

9. Housing according to one of claims 1 to 8, in which the radiator (3) is made of thermally conductive material.

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