Housing body for electronic module

Abstract

To provide a housing body that houses an electronic module such as an in-vehicle ECU and has high heat dissipation efficiency.SOLUTION: A housing body for an electronic module that houses an electronic module includes a case that houses the electronic module inside and is formed by joining a resin upper cover that covers one side of the electronic module and a lower cover that covers the other side of the electronic module, and at least one metal structure for heat dissipation which is attached by penetrating through the upper cover such that one end locally contacts one side of the electronic module housed inside the case and the other end protrudes from the upper cover.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a housing body for accommodating an electronic module such as a circuit board, and more particularly to a housing body for an electronic module having high heat dissipation performance for efficiently dissipating heat generated from the electronic module. [Background technology]

[0002] Vehicles such as automobiles are equipped with electronic control units (ECUs: Electric Control Units) for engine control, motor control, and the like. Such on-vehicle electronic control units (ECUs) are usually equipped with circuit boards on which heat-generating components are mounted. The heat-generating components are electronic elements that generate a particularly large amount of heat, such as processors and IC chips. In the above-mentioned electronic control units, the circuit board needs to be housed inside a case (housing body) in order to protect the heat-generating components and the circuit board. For this reason, it is important to efficiently release the heat generated by the heat-generating components to the outside of the case.

[0003] For example, as disclosed in the following Patent Documents 1 to 6, there have been proposed heat dissipation structures in which heat dissipation fins are formed on a housing and heat generated inside the housing is dissipated through the fins. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2013-084854 A [Patent Document 2] JP 2014-192456 A [Patent Document 3] JP 2017-001412 A [Patent Document 4] JP 2019-096766 A [Patent Document 5] Patent Publication No. 2021-163875 [Patent Document 6] Patent Publication No. 2022-075116 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the heat dissipation structure using heat dissipation fins has a problem that the entire housing becomes relatively large because the fins require a relatively large surface area to be mounted on the housing that houses the circuit board equipped with the heat generating components. If the heat dissipation structure using fins is made smaller in size in order to reduce the size, the heat dissipation efficiency also decreases. In addition, the fins must be made of a metal with high thermal conductivity, which tends to increase the weight of the housing.

[0006] The present inventors have actively conducted research and development into the heat dissipation structure of a housing body (chassis) that houses an on-vehicle ECU, and have now developed an improved housing body that enables higher heat dissipation efficiency, smaller size, lighter weight, and lower costs.

[0007] SUMMARY OF THE PRESENT DISCLOSURE An object of the present invention is to provide a housing body for accommodating an electronic module such as an in-vehicle ECU, which has high heat dissipation efficiency. [Means for solving the problem]

[0008] In order to achieve the above-mentioned object, the housing body of the present invention is a housing body for an electronic module that accommodates an electronic module, and is characterized in that it comprises a case that accommodates the electronic module inside and is formed by joining a resin upper cover that covers one side of the electronic module and a lower cover that covers the other side of the electronic module, at least one metal structure for heat dissipation that is attached by penetrating the upper cover so that one end locally contacts the one side of the electronic module accommodated inside the case and the other end protrudes from the upper cover, and a metal plate that is adhered to the back surface of the upper cover of the case. Effect of the Invention

[0009] According to the present invention, the heat generated from the electronic module accommodated in the housing body can be efficiently dissipated, and an increase in temperature of the electronic module can be suppressed. A housing body for an electronic module having high heat dissipation efficiency is provided. [Brief description of the drawings]

[0010] [Figure 1] 1 is an exploded perspective view showing a configuration example of an electronic module housing body according to an embodiment of the present invention; [Diagram 2] 1 is a perspective view showing a configuration example of an electronic module housing body according to an embodiment of the present invention; [Diagram 3] 1A and 1B are a side view and a partial cross-sectional view showing a first configuration example of an electronic module housing body in an embodiment of the present invention. [Figure 4] 1A to 1C are diagrams showing an example of the configuration of a metal structure 20. [Diagram 5] 6A to 6C are diagrams illustrating an example of a simulation of a temperature rise in a housing body according to an embodiment of the present invention. [Figure 6] 6A to 6C are diagrams illustrating an example of an experiment on temperature rise of a housing body according to an embodiment of the present invention. [Figure 7] 11 is an exploded perspective view showing a second configuration example of an electronic module housing body in an embodiment of the present invention. FIG. [Figure 8] 11 is a perspective view showing a second configuration example of an electronic module housing body in an embodiment of the present invention. FIG. [Figure 9] 5A and 5B are a side view and a partial cross-sectional view showing a second configuration example of an electronic module housing body in an embodiment of the present invention. [Figure 10] 13 is a diagram showing a state in which a card edge connector is connected to the thin external connection terminal of the housing body. FIG. [Figure 11] 6A to 6C are diagrams illustrating an example of a simulation of a temperature rise in a housing body according to an embodiment of the present invention. [Figure 12] 11A and 11B are diagrams illustrating a third configuration example of an electronic module housing body in an embodiment of the present invention. [Figure 13] 13A and 13B are diagrams illustrating a fourth configuration example of an electronic module housing body in an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. However, such an embodiment does not limit the technical scope of the present invention. An embodiment of the present invention will be described with reference to specific drawings.

[0012] Fig. 1 is an exploded perspective view showing a first configuration example of an electronic module housing body in an embodiment of the present invention. Fig. 2 is a perspective view showing the first configuration example of an electronic module housing body in an embodiment of the present invention, Fig. 2(a) is a perspective view seen from above, and Fig. 2(b) is a perspective view seen from below. Fig. 3 is a side view (Fig. 3(a)) and a partial cross-sectional view (Fig. 3(b)) showing the first configuration example of an electronic module housing body in an embodiment of the present invention.

[0013] The housing body for the electronic module (hereinafter referred to as the "housing body") is a housing (case) that houses the electronic module 50, and is composed of a case 10 formed by joining a resin upper cover 11 that covers one side 50a of the electronic module 50 that is configured as a circuit board, and a lower cover 12 that covers the other side 50b of the electronic module 50.

[0014] Furthermore, at least one, preferably a plurality of, metal structures 20 are attached to the case 10, and the metal structures 20 are preferably formed in a pin shape and are attached to the upper cover 11 by penetrating the upper cover 11 so that one end 20a thereof locally contacts one surface 50a of the electronic module 50 housed inside the case 10 and the other end 20b thereof protrudes from the upper cover 11. Also, a breathable membrane cap 13 for adjusting the pressure inside the case 10 is attached to the upper cover 11.

[0015] The upper cover 11 and the lower cover 12 are joined together with a sealing material 14 sandwiched therebetween to keep the mating surfaces waterproof, thereby forming the case 10. The electronic module 50 is housed in the internal space of the case 10 so as to be covered from both sides by the upper cover 11 and the lower cover 12, and both covers are fixed together by, for example, screw means 70.

[0016] The upper cover 11 is made of a synthetic resin having an electromagnetic wave shielding function, for example, PA6 (6 nylon) / CF30 (30% carbon). As will be described later, the upper cover 11 is formed in a form in which the metal structure 20 is inserted through the upper cover 11 by, for example, insert molding using a mold in which the metal structure 20 is arranged at a predetermined position.

[0017] The lower cover 12 is a bottom cover that covers the other side 50b, which is the side opposite to the one side 50a of the electronic module 50, and is made of either a metal material such as steel or a synthetic resin having an electromagnetic wave shielding function, and if made of synthetic resin, it may be the same material as the upper cover 11 or a different material. The lower cover 12 is formed by injection molding.

[0018] The electronic module 50 is, for example, a circuit board constituting an in-vehicle ECU (Electric Control unit), and various electronic elements 52 such as IC chips are mounted on a printed circuit board 51 on which metal wiring is printed. External connection terminals 53 are formed on the edges of the circuit board (electronic module) 50, and the electronic module 50 is housed in the case 10 with the external connection terminals 53 exposed to the outside from the case 10 after being waterproofed with a sealing material or the like. The external connection terminals 53 are electrically connected to a connector (not shown).

[0019] A thermal interface material (TIM) 60 is thinly applied in a thin film or sheet shape on a heat source on an electronic module 50, which is a circuit board, that is, a specific electronic element 52 mounted on a printed circuit board 51. The thickness of the thermal interface material is about 1 to 2 mm. The thermal interface material (TIM) 60 can be in various forms, such as thermally conductive grease, thermally conductive gel, and thermally conductive sheet. The thermal interface material (TIM) 60 is partially disposed on the electronic element 52, which is a heat source of the printed circuit board 51, and performs a thermal conduction function between the electronic element 52 and the metal structure 20. One end 20a of the metal structure 20 contacts the electronic element 52 via the thermal interface material (TIM) 60.

[0020] FIG. 4 is a diagram showing a configuration example of the metal structure 20. The metal structure 20 is preferably a metal pin, and is formed, for example, in a generally cylindrical shape. FIG. 4(a) shows a first shape example of the metal structure 20, and FIG. 4(b) shows a second shape example of the metal structure 20. In both the examples of FIG. 4(a) and FIG. 4(b), one end 20a of the metal structure 20 that contacts the circuit board 50 constitutes a bottom surface portion with a relatively large diameter in order to secure a relatively wide contact area with the circuit board 50. In the shape example of FIG. 4(a), in order to reduce the weight of the metal structure, the cylindrical portion extending from the one end 20a side to the other end 20b side is formed in a hollow shape. In the shape example of FIG. 4(b), the part of the other end 20b of the metal structure 20 that protrudes from the upper cover 11 and is exposed to the outside may be formed in a cross-sectional shape. In order to increase heat dissipation, the surface area is set as large as possible. In the shape example of FIG. 4(b), the inside of the cylinder has a dense structure and has high thermal conductivity. 1 to 3 show examples of the configuration of a housing body in which the metal structure 20 shown in Fig. 4(a) is adopted. The shape of the metal structure 20 is not limited to the above example, and various shapes that can provide a relatively large surface area, such as a rectangular column shape or a thin and elongated plate shape (fin shape), can be adopted.

[0021] The metal structure 20 is a metal pin made of a high thermal conductivity material such as copper or aluminum alloy, and a copper pin, which has a higher thermal conductivity, is particularly preferred. The metal structure 20 is attached by being inserted through the upper cover 11; specifically, when the electronic module 50 is housed inside the case 10, the metal structure 20 is attached to the upper cover 11 at a length and position such that it comes into contact, via a thermal interface material (TIM), with the upper part of a localized portion that is directly above or in the vicinity of the electronic element 52, which is a heat source arranged on the printed circuit board 51.

[0022] One end 20a of the metal structure 20 contacts a local portion of the electronic module 50 inside the case 10, and the other end 20b of the metal structure 20 is attached so as to protrude outside the upper cover 11, and heat generated in the local portion of the electronic module 50 is dissipated to the outside of the case 10 due to the thermal conductivity performance of the metal structure 20.

[0023] The metal structure 20 is attached to the upper cover 11 in a changeable mounting position in accordance with a wide variety of electronic modules 50 having different positions for the electronic elements 52 that are heat sources. In insert molding, by changing the position of the metal structure 20 placed in the mold, it is possible to form the upper cover 11 with the metal structure 20 attached in a desired position.

[0024] At the penetration portion of the upper cover 11 where the resin upper cover 11 and the metal structure 20 are joined, the metal structure 20 is joined to the upper cover without peeling off within the range of deformation due to thermal expansion of the upper cover 11.

[0025] Since the upper cover 11, which is made of a resin material, and the metal structure 20 have different thermal expansion coefficients, the amount of deformation thereof differs according to temperature changes caused by heat generation or the like of the electronic module 50. For example, heat conduction through the metal structure 20 is also transmitted to the upper cover 11, and the amount of deformation of the upper cover 11, which is made of a resin material, is usually greater than the amount of deformation of the metal structure 20, which is made of metal, in response to a rise in temperature, so that the difference in the amount of deformation may cause the joint between the metal structure 20 and the upper cover 11 to separate, or a relative misalignment may occur, resulting in the joint coming off.

[0026] Therefore, the portion where the metal structure 20 is joined to the upper cover 11 is subjected to a processing process that maintains the joined state between the upper cover 11 and the metal structure 20 without peeling off even when the metal structure 20 expands and contracts due to temperature changes, and the metal structure 20 is fixed to the upper cover 11 through the processing process. As the processing process, for example, a laser processing method can be adopted in which the peripheral surface of the metal structure 20 is laser scanned in two scanning directions that cross each other on the area that is inserted into the upper cover 11 and contacts the upper cover. The laser processing method is disclosed in detail in Japanese Patent No. 4020957 and is known as a direct joining technique of metal and dissimilar materials called "Laseridge" (registered trademark) or "Laseridge" (registered trademark). By using this technique, the joint portion of the metal structure 20 with the upper cover is firmly joined and fixed to the upper cover 11 without peeling off within the range of deformation due to thermal expansion of the upper cover 11 caused by temperature changes due to heat conduction, etc. As a result, the metal structure 11 does not come off or have a gap, and a completely tight joint that maintains waterproof performance is possible. The joining technique between the upper cover 11 and the metal structure 20 is not limited to the above processing method, and other processing methods may be adopted. Note that, in Fig. 4(c) and Fig. 4(d), the region 20c of the metal structure 20 to which the laser processing is applied is shown.

[0027] Fig. 5 is a diagram illustrating an example of a simulation of a temperature rise of a housing body in an embodiment of the present invention. Fig. 5(a) shows the result of a simulation of a temperature rise of a housing body having a conventional heat dissipation fin structure as a comparative example, and Fig. 5(b) shows the result of a simulation of a temperature rise of a housing body in this embodiment. In both simulations, a heater is placed as a heat source on a printed circuit board inside the housing body, and the temperature change when the same power is supplied to the heater is simulated.

[0028] In FIG. 5(a), the temperature measurement point CH1 is the arrangement position of the heater, and the temperature of the heater itself is measured. The temperature measurement points CH2 and CH3 are the arrangement positions of the heat dissipation fins, and the temperature of the heat dissipation fins is measured. In FIG. 5(b), the temperature measurement point CH4 is the arrangement position of the heater, and the temperature of the heater itself is measured. The temperature measurement points CH5, CH6, and CH7 are the arrangement positions of the metal structure 20, and the temperature of the metal structure (heat dissipation pin) 20 is measured. In FIG. 5(a), the temperature measurement points CH2 and CH3 of the heat dissipation fin are positions around the temperature measurement point CH1 of the heater, and in FIG. 5(b), the temperature measurement points CH5 and CH6 of the metal structure 20 are the arrangement positions of the metal structure 20 arranged directly above or in the immediate vicinity of the temperature measurement point CH4 of the heater, and the temperature measurement point CH7 of the metal structure 20 is the periphery of the heater away from the heater, and is an arrangement position farther from the heater than the temperature measurement points CH5 and CH6.

[0029] Comparing the temperature change graphs of Figure 5(a) and Figure 5(b), the temperature at the heater temperature measurement point CH1 in Figure 5(a) exceeded 140°C, while the temperature at the heater temperature measurement point CH4 in Figure 5(b) was about 80°C, and the temperature of the heater itself dropped by more than 60°C, resulting in the suppression of the temperature rise. The temperatures of the temperature measurement points CH5 and CH6 of the metal structure 20 were higher than the temperature measurement points CH2 and CH3 of the heat dissipation fin, and it was confirmed that the heat generated by the heater was dissipated by the high thermal conductivity of the metal structure 20, and the effect of significantly suppressing the temperature rise of the heater was confirmed.

[0030] 6 is a diagram for explaining an example of an experiment on a temperature rise of a housing body in the embodiment of the present invention, showing the results of an actual temperature rise measurement experiment under conditions similar to those of the temperature rise simulation in FIG.

[0031] Fig. 6(a) shows the results of a temperature measurement experiment on a housing body having a conventional heat dissipation fin structure as a comparative example, and Fig. 6(b) shows the results of a temperature measurement experiment on a housing body in this embodiment. As with the simulation example in Fig. 5, in both temperature measurement experiments, a heater was placed as a heat source on the printed circuit board inside the housing body, and the same power was supplied to the heater to measure the temperature change.

[0032] In FIG. 6(a), temperature measurement point CH1 is the position where the heater is arranged, and the temperature of the heater itself is measured. Temperature measurement points CH2, CH3, and CH4 are the positions where the heat dissipation fins are arranged, and the temperature of the heat dissipation fins is measured. Temperature measurement point CH5 is the position of the metal upper cover close to directly above the heater, and the temperature is measured. In FIG. 6(b), temperature measurement point CH6 is the position where the heater is arranged, and the temperature of the heater itself is measured. Temperature measurement points CH7, CH8, CH9, and CH10 are the positions where the metal structure 20 is arranged, and the temperature of the metal structure (heat dissipation pin) 20 is measured. In addition, in Figure 5 (b), temperature measurement points CH8 and CH9 of the metal structure 20 are positions of the metal structure 20 that are arranged directly above or very close to temperature measurement point CH6 of the heater, temperature measurement point CH10 of the metal structure 20 is located around the heater away from the heater and is located farther from the heater than temperature measurement points CH8 and CH9, and temperature measurement point CH7 of the metal structure 20 is located even farther from the heater than temperature measurement point CH10.

[0033] Comparing the temperature change graphs of Figure 6(a) and Figure 6(b), the temperature at the heater temperature measurement point CH1 in Figure 6(a) exceeds 190°C, while the temperature at the heater temperature measurement point CH6 in Figure 6(b) is around 120°C, and the temperature of the heater itself drops by more than 70°C, and the effect of suppressing temperature rise was confirmed by actual temperature measurement experiments. The temperature at the temperature measurement point of the metal structure 20 is higher than the temperature of the heat dissipation fins, and the high thermal conductivity of the metal structure 20 promotes heat dissipation from the heater, resulting in high heat dissipation performance.

[0034] Next, a second configuration example of the electronic module housing body in the embodiment of the present invention will be described. Fig. 7 is an exploded perspective view showing the second configuration example of the electronic module housing body in the embodiment of the present invention. Fig. 8 is a perspective view showing the second configuration example of the electronic module housing body in the embodiment of the present invention, Fig. 8(a) is a perspective view seen from above, and Fig. 8(b) is a perspective view seen from below. Fig. 9 is a side view (Fig. 9(a)) and a partial cross-sectional view (Fig. 9(b)) showing the second configuration example of the electronic module housing body in the embodiment of the present invention.

[0035] The second configuration example of the housing body is formed to have a thinner shape compared to the first configuration example of the housing body shown in Figures 1 to 6. By thinning the external connection terminal 53 provided on the electronic module 50 and making it electrically connectable to a thin connector, for example, a so-called card edge connector, the entire housing body can be made thinner and smaller. By making the housing body smaller and thinner, the mountability in a vehicle is improved. Note that Figures 7 to 9 show the second configuration example of the housing body in which the metal structure 20 shown in Figure 4(b) is adopted.

[0036] Figure 10 shows the state in which a card edge connector 80 is connected to the thin external connection terminal 53 of the housing body, where Figure 10(a) is a side view of the housing body to which the card edge connector 80 is connected, and Figure 10(b) is an oblique view thereof.

[0037] 9(b), a thermal interface material (TIM) is also disposed on the other side (the side facing the lower cover 12) of the circuit board 50 inside the housing, and the lower cover 12 is formed to contact the circuit board 50 via this thermal interface material. The thickness of the lower cover 12 in the height direction is reduced to set the gap between the circuit board 50 housed inside to approximately the thickness of the thermal interface material 60, and the circuit board 50 and the lower cover 12 are in contact via the thermal interface material 60, so that heat generated in the circuit board 50 is conducted to the lower cover 12 in addition to the metal structure 20 attached to the upper cover 11, and dissipated. This further improves the heat dissipation efficiency.

[0038] FIG. 11 is a diagram for explaining a temperature rise simulation example of the housing body in the embodiment of the present invention. FIG. 11(a) is the same as FIG. 5(a) and shows the temperature rise simulation result of a comparative example of a housing body having a conventional heat dissipation fin structure, FIG. 11(b) is the same as FIG. 5(b) and shows the temperature rise simulation result of the housing body in the first configuration example shown in FIG. 1-3, and FIG. 11(c) shows the temperature rise simulation result of the housing body in the second configuration example shown in FIG. 7-9. As shown in FIG. 11(c), in the second configuration example, the temperature rise of the heater as a heat source is further suppressed compared to the first configuration example, and a higher heat dissipation efficiency is obtained. The back side of the circuit board 50 on which the heat source is arranged contacts the lower cover 12 via a thermal interface material (TIM), and the heat dissipation effect due to the contact is additionally generated, so that the temperature of the heat source is further reduced.

[0039] Figure 12 shows a third configuration example of a housing body for an electronic module in an embodiment of the present invention, where Figure 12(a) is an oblique view from above, Figure 12(b) is a plan view, and Figure 12(c) is a cross-sectional view along the dashed line in Figure 12(b).

[0040] The third configuration example of the housing body, like the first and second configuration examples of the housing body described above, has a case 10 that houses therein an electronic module 50 configured with an electronic element 52 that is a heating element and a printed circuit board 51, and the case 10 is formed by joining a resin upper cover 11 that covers one side of the electronic module 50 and a lower cover 12 that covers the other side of the electronic module 50. Furthermore, at least one metal structure 20 for heat dissipation is provided, which is attached by penetrating the upper cover 11 so that one end locally contacts one side of the electronic module 50 housed inside the case 10 and the other end protrudes from the upper cover.

[0041] Furthermore, in the third configuration example, the housing body is configured such that a metal plate 15 is adhered to the back surface (the inner surface of the case 10) of the upper cover 11 of the case 10, as shown in FIG. 12(c).

[0042] The metal plate 15 is a metal plate having high thermal conductivity, such as a copper plate, and is disposed such that its end is in contact with the side peripheral surface of one end 20a of the metal structure 20. Alternatively, it may be disposed slightly apart within a range in which thermal conductivity is not significantly reduced. A part of the heat transferred from the electronic element 52, which is a heat generating body, to the metal plate 15 is transferred from the metal plate 15 to the upper cover 11 made of resin and dissipated to the outside. The upper cover 11 is made of resin and has a relatively high thermal emissivity compared to metals, etc., and the heat transferred to the metal plate 15 is widely propagated to the upper cover 11 in contact with the metal plate 15, and is effectively dissipated to the outside by thermal radiation from the surface of the upper cover 11. Heat propagates not only in the height direction of the metal structure 20 (thickness direction of the case 10) but also in the direction in which the metal plate 15 in contact with it is arranged, i.e., the lateral direction of the metal structure 20 (the lateral direction of the case 10), thereby allowing the heat to propagate effectively, thereby improving the heat dissipation efficiency.

[0043] The metal plate 15, like the metal structure 20, is formed by insert molding in a state of being in contact with and attached to a predetermined area of ​​the rear surface of the upper cover 11. In addition, by using the metal plate 15 whose surface has been roughened by various techniques, the contact area with the upper cover 11 is increased microscopically, and the efficiency of heat transfer to the upper cover 11 can be further improved.

[0044] 12, an electronic element 52' that serves as a heat generating element is also mounted on the back side of the printed circuit board 51, and a metal structure 20' for heat dissipation that comes into contact with the electronic element 52' via a thermal interface material 60 is attached by penetrating the lower cover 12. When the lower cover 12 is a resin molded body, similar to the upper cover 11, the surface of the metal structure 20' is processed using the above-mentioned direct bonding technology of metal and dissimilar materials called "Laseridge" (registered trademark) or "Laseridge" (registered trademark), thereby increasing the contact area with the lower cover 12 microscopically, and further improving the efficiency of heat transfer to the lower cover 11.

[0045] The surface of the metal structure 20 of the present invention may be resin-coated. Generally, resin materials have a higher thermal emissivity than metals, so coating the metal structure 20 with a resin material having a higher thermal emissivity than the metal structure 20 increases the thermal emissivity of the metal structure 20, further improving the heat dissipation effect.

[0046] Figure 13 shows a fourth configuration example of a housing body for an electronic module in an embodiment of the present invention, where Figure 13(a) is an oblique view from above, Figure 13(b) is a plan view, and Figure 13(c) is a cross-sectional view along the dashed line in Figure 13(b).

[0047] The fourth configuration example of the housing body, like the first to third configuration examples of the housing body described above, has a case 10 that houses an electronic module 50 comprising an electronic element 52 which is a heating element and a printed circuit board 51, and the case 10 is formed by joining a resin upper cover 11 that covers one side of the electronic module 50 and a lower cover 12 that covers the other side of the electronic module 50.

[0048] 12(c), the housing body further includes a metal plate 15 adhered to the back surface (the inner surface of the case 10) of the upper cover 11 of the case 10, and the metal plate 15 is disposed so as to contact one surface of the electronic module 50 housed inside the case 10. More specifically, the metal plate 15 contacts, via the thermal interface material 60, the electronic element 52, which is a heat generating element mounted on the printed circuit board 51.

[0049] As in the third configuration example, the metal plate 15 is a metal plate with high thermal conductivity, such as a copper plate, and is disposed in direct contact with the electronic element 52 via the thermal interface material 60. Heat transferred from the electronic element 52, which is a heat generating body, to the metal plate 15 is diffused and transmitted by the metal plate 15, and is further transferred from the metal plate 15 to the upper cover 11 made of resin and dissipated to the outside. The upper cover 11 is made of resin and has a relatively high thermal emissivity compared to metals, etc., and the heat transferred to the metal plate 15 is propagated widely to the upper cover 11 in contact with the metal plate 15, and is effectively dissipated to the outside by thermal radiation from the surface of the upper cover 11. The heat is diffused widely in the metal plate 15, which has a large surface area, and is efficiently dissipated.

[0050] As in the third configuration example, the metal plate 15 is formed by insert molding in a state where it is in contact with the entire surface of a predetermined area of ​​the rear surface of the upper cover 11 and is attached to it. In addition, by using the metal plate 15 whose surface has been roughened by various techniques, the contact area with the upper cover 11 is increased microscopically, and the efficiency of heat transfer to the upper cover 11 can be further improved.

[0051] In the fourth configuration example of Figure 13, similar to the third configuration example described above, an electronic element 52' that serves as a heat generating element is also mounted on the back side of the printed circuit board 51, and a metal structure 20' for heat dissipation that contacts the electronic element 52' via a thermal interface material 60 is attached by penetrating the lower cover 12.

[0052] When the lower cover 12 is a resin molded body, by using a metal structure 20' whose surface has been roughened by various techniques, as with the upper cover 11, the contact area with the lower cover 12 can be increased microscopically, and the efficiency of heat transfer to the lower cover 12 can be further improved.

[0053] The surface of the metal plate 15 of the present invention may be resin-coated. Generally, resin materials have a higher thermal emissivity than metals, so coating the metal plate 15 with a resin material having a higher thermal emissivity than the metal plate 15 increases the thermal emissivity of the metal plate 15, further improving the heat dissipation effect.

[0054] The housing body of the present invention is ideal for accommodating an in-vehicle ECU as an electronic module, but is not limited to this and can be applied to accommodate various electronic modules, particularly preferably in-vehicle electronic modules, such as a control unit that controls the motor drive of an electric vehicle.

[0055] It should be noted that the present invention is not limited to the above-described embodiments, and it goes without saying that the present invention includes design changes that do not deviate from the gist of the present invention, including various modifications and alterations that would occur to a person with ordinary knowledge in the field of the present invention. [Explanation of symbols]

[0056] 10: case, 11: upper cover, 12: lower cover, 13: breathable membrane cap, 14: sealing material, 15: metal plate, 20: metal structure, 20a: one end of the metal structure, 20b: other end of the metal structure, 50: electronic module (circuit board), 50a: one side of the electronic module, 50b: other side of the electronic module, 51: printed circuit board, 52: electronic element, 53: external connection terminal, 60: thermal interface material (TIM), 70: screw means

Claims

1. A housing body for an electronic module that houses an electronic module, a case that houses the electronic module and is formed by joining a resin upper cover that covers one side of the electronic module and a resin lower cover that covers the other side of the electronic module; and at least one metal structure for heat dissipation that is attached through the upper cover so that one end locally contacts the one side side of the electronic module accommodated inside the case and the other end protrudes from the upper cover.

2. 2. A housing body for an electronic module as described in claim 1, characterized in that a thermal interface material is at least partially arranged in a thin film form on one side of the electronic module, and the one end of the metal structure contacts the one side of the electronic module via the thermal interface material.

3. 3. A housing body for an electronic module as described in claim 2, characterized in that a thin film of another thermal interface material is at least partially arranged on the other side of the electronic module, and the inner surface of the lower cover contacts the other side of the electronic module via the other thermal interface material.

4. 3. The housing for an electronic module according to claim 2, wherein the one end of the metal structure contacts a portion of a heat source mounted on the one side of the electronic module or a portion thereof adjacent thereto via the thermal interface material.

5. 2. The housing body for an electronic module according to claim 1, wherein the metal structure is formed in a cylindrical shape, and the one end of the metal structure that contacts the electronic module has a flat surface that is formed wider than other portions.

6. 6. The electronic module housing according to claim 5, wherein the metal structure has a hollow portion that opens at the other end.

7. 6. The housing body for an electronic module according to claim 5, wherein the other end of the metal structure protruding from the upper cover has a cross-shaped cross section.

8. 2. The electronic module housing as claimed in claim 1, wherein said metallic structure is a copper pin.

9. 2. The electronic module housing according to claim 1, wherein the lower cover is a resin cover having an electromagnetic wave shielding function.

10. 2. The housing body for an electronic module according to claim 1, wherein the electronic module is an in-vehicle electronic control unit.

11. A housing body for an electronic module that houses an electronic module, a case that houses the electronic module and is formed by joining a resin upper cover that covers one side of the electronic module and a resin lower cover that covers the other side of the electronic module; at least one metal structure for heat dissipation, the metal structure being attached to the upper cover so as to penetrate the upper cover and have one end locally contacting the one surface side of the electronic module housed inside the case and the other end protruding from the upper cover; a metal plate attached to the back surface of the upper cover of the case; A housing body for an electronic module comprising:

12. 12. The housing for an electronic module according to claim 11, wherein the metal plate is disposed such that an end portion thereof contacts a side peripheral surface of the one end of the metal structure.

13. 12. The electronic module housing according to claim 11, wherein the surface of the metal structure is resin-coated.

14. The housing body for an electronic module as described in claim 11, further comprising at least one other metal structure for heat dissipation that is attached through the lower cover so that one end locally contacts the other side side of the electronic module accommodated inside the case and the other end protrudes from the lower cover.

15. 12. The housing body for an electronic module according to claim 11, wherein the electronic module is an in-vehicle electronic control unit.

16. A housing body for an electronic module that houses an electronic module, a case that houses the electronic module and is formed by joining a resin upper cover that covers one side of the electronic module and a resin lower cover that covers the other side of the electronic module; a metal plate that is attached to the back surface of the upper cover of the case and that comes into contact with the one surface side of the electronic module housed inside the case; A housing body for an electronic module comprising:

17. The housing body for an electronic module as described in claim 16, further comprising at least one metal structure for heat dissipation that is attached through the lower cover so that one end locally contacts the other side side of the electronic module accommodated inside the case and the other end protrudes from the lower cover.

18. 17. The electronic module housing according to claim 16, wherein the surface of the metal plate is resin-coated.

19. 17. The housing body for an electronic module according to claim 16, wherein the electronic module is an in-vehicle electronic control unit.

20. An electronic module; 20. An electronic module assembly comprising: an electronic module housing body according to any one of claims 1 to 19, which houses the electronic module.

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