Electronic device

Abstract

To provide an electronic device which achieves cooling performance and waterproofness without using a fan.SOLUTION: An electronic device includes: a housing 2 which houses an electronic component 3 in an internal space S2 and is provided with a suction port 2i which is open at a position lower than the electronic component 3 and an exhaust port 2x which is open at a position above the electronic component 3 and in which a ventilation passage Fc of cooling air for the electronic component 3 is formed in an area from the suction port 2i to the exhaust port 2x of the internal space S2; and a waterproof mechanism which maintains circulation of the cooling air and prevents water droplets falling from above from entering the internal space S2 from the exhaust port 2x.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to electronic devices. [Background technology]

[0002] In recent years, the amount of heat generated by electronic components such as ICs mounted on electronic devices has tended to increase in response to the demand for high computing power, and high cooling performance is required for electronic devices. Furthermore, electronic devices mounted on vehicles, etc., require waterproofing, not only from rain outside the vehicle cabin, but also from concerns about drinking water spilled by passengers inside the vehicle.

[0003] Therefore, electronic devices have been proposed that improve waterproofing and cooling performance by installing a fan in the housing that houses the electronic components and providing filters with a water-repellent coating such as fluorine on the air intake and exhaust ports (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. WO2010 / 122715 (paragraphs 0019-0021, Figure 1) Summary of the Invention [Problem to be solved by the invention]

[0005] However, from the perspective of environmental measures, cost reduction, and simplification of manufacturing processes, the market is calling for fewer parts. Therefore, installing expensive fans not only increases costs, but also limits the space available for installing electronic components. Furthermore, motors, which are the driving components, have a limited lifespan and there is concern that they may malfunction due to lack of durability, so there is a demand for fanless designs.

[0006] The present disclosure discloses a technique for solving the above-mentioned problems, and aims to provide an electronic device that achieves both cooling performance and waterproofing without using a fan. [Means for solving the problem]

[0007] The electronic device disclosed in the present disclosure is characterized by comprising a housing that houses electronic components in an internal space, and that has an air intake port that opens vertically below the electronic components when installed to communicate outside air with the internal space, and an exhaust port that opens at an upper position to communicate outside air with the internal space, and that forms a ventilation path for cooling air for the electronic components in the internal space from the air intake port to the exhaust port by an ascending air current driven by the heat of the electronic components, and a waterproof mechanism that maintains the ventilation of the cooling air and prevents water droplets falling from above from entering the internal space through the exhaust port. [Effects of the Invention]

[0008] According to the electronic device of the present disclosure, waterproofing can be achieved without compromising the ventilation volume achieved by gravity ventilation, so that an electronic device that combines cooling performance and waterproofing can be obtained without using a fan. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a perspective view showing the appearance of an electronic device according to a first embodiment. [Figure 2] 2A and 2B are a front cross-sectional view and a side cross-sectional view, respectively, for explaining the configuration of the electronic device according to the first embodiment. [Figure 3] 3 is a partial enlarged view for explaining the structure of the ventilation filter used in the ventilation opening of the electronic device according to the first embodiment. FIG. [Figure 4] 4 is a cross-sectional view illustrating the inclination of the ventilation filter when the electronic device according to the first embodiment is installed. FIG. [Figure 5]5A and 5B are partial cross-sectional views in side view illustrating the structure of the exhaust port portion of electronic devices according to first and second modifications of the first embodiment, respectively. [Figure 6] FIG. 10 is a cross-sectional view of the electronic device as seen from the front for explaining the configuration of the electronic device according to the second embodiment. [Figure 7] FIG. 10 is a cross-sectional view illustrating the configuration of an electronic device according to a modified example of the second embodiment, as viewed from the front. [Figure 8] 8A and 8B are a cross-sectional view in front view for explaining the configuration of the electronic device according to the third embodiment, and a cross-sectional view in obliquely upward side view of the electronic component portion, respectively. [Figure 9] 9A and 9B are a cross-sectional view in front view illustrating the configuration of an electronic device according to a modification of the third embodiment, and a cross-sectional view in obliquely upward side view of an electronic component portion, respectively. [Figure 10] FIG. 10 is a front view of a radar portion for explaining the configuration of an electronic device according to a fourth embodiment. [Figure 11] FIG. 11 is a cross-sectional view of an electronic component portion as seen obliquely from above, illustrating the configuration of a radar device according to a modified example of the fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Embodiment 1 1 to 4 are diagrams illustrating the configuration of an electronic device according to a first embodiment, with Fig. 1 being a perspective view showing the appearance of the electronic device, Fig. 2A being a cross-sectional view taken along line AA in Fig. 1 as viewed from the front, and Fig. 2B being a cross-sectional view taken along line BB in Fig. 1 as viewed from the right side. Fig. 3 is a partially enlarged view of the filter surface, i.e., a direction away from the thickness direction, to illustrate the structure of a ventilation filter used in an air vent, and Fig. 4 is a cross-sectional view including a vertical line parallel to the filter surface to illustrate the relationship between the inclination of the filter surface and the sliding angle of water droplets when the electronic device is installed in at least an air vent (exhaust port) on the exhaust side.

[0011] 1, 2A, and 2B, electronic device 1 according to the first embodiment accommodates electronic components 3, which are heat-generating bodies, in an internal space S2 of a housing 2 constituted by a cover 21 and a housing 22. An air intake 2i is provided below electronic components 3 in the vertical direction (gravity direction) in housing 2 for taking in outside air to cool electronic components 3, and an exhaust 2x is provided above electronic components 3 for absorbing heat from electronic components 3 and discharging heated air to the outside.

[0012] In this disclosure, the vertical direction when the electronic device 1 is installed in a vehicle or the like is defined as the z direction, the left-right direction as the x direction, and the front-to-back direction as the y direction, with the upward facing surface being the top surface 2ft and the downward facing surface being the bottom surface 2fb. The forward facing surface is referred to as the front surface, the rear facing surface as the back surface, the right facing surface as the right surface, and the left facing surface as the left surface, but the front, back, right surface, and left surface will be collectively referred to as the side surface 2fs.

[0013] The electronic component 3 is a heat-generating component such as an IC (Integrated Circuit), and is fixed with screws 7 to fixing bosses 22b on the inner surface of the housing 22 and mounted on a substrate 4 arranged parallel to the xz plane. When the electronic device 1 is operated, the electronic component 3 generates heat and its temperature rises. The high-temperature electronic component heats the gas (air) inside the housing, causing its temperature to rise. The heated air becomes lighter in specific gravity than the outside air. Therefore, due to the difference in position (height difference) between the air intake 2i and the air exhaust 2x in the vertical direction (z direction), an upward air current known as gravity ventilation or temperature difference ventilation occurs, in which air is drawn in through the air intake 2i and exhausted through the air exhaust 2x, cooling the electronic component 3.

[0014] In the electronic device 1 of the present disclosure, outside air, which is cooler than the air inside the housing, is drawn in through the air intake 2i, and air warmed by heat from the electronic components 3 flows upward and is discharged through the air exhaust 2x. The imaginary line Lix connecting the center position Pi of the air intake 2i and the center position Px of the air exhaust 2x is the line connecting the air intake 2i and the air exhaust 2x in the shortest distance, forming the ventilation path Fc with the highest air flow velocity. Therefore, by positioning the electronic components 3 and the board 4 close to the imaginary line Lix, the cooling effect of the electronic components 3 can be improved. Note that "close to the imaginary line Lix" means that the area of ​​the internal space S2 is closer to the imaginary line Lix than the upper or lower end, or that the area of ​​the portion closer to the imaginary line Lix than the upper or lower end is larger than the area of ​​the portion closer to the imaginary line Lix than the upper or lower end.

[0015] Meanwhile, the intake port 2i is located on the bottom surface 2fb, and the exhaust port 2x is located on the back surface (side surface 2fs), each on a different surface of the housing 2. They are arranged at different positions in the front-to-back direction (y direction) so that the virtual line Lix is ​​inclined with respect to the z direction both in the zy plane and in the zx plane. This allows spaces to be formed in front of and behind the virtual line Lix (y direction) and on the left and right (x direction), making it easy to arrange the electronic components 3 and the board 4 so that they approximate the virtual line Lix.

[0016] Since the board 4 is arranged so that it extends parallel to the xz plane, heat buildup can be eliminated without obstructing the airflow. Other components that are not depicted may be built into the housing. However, by ensuring that there is nothing blocking the virtual line Lix, except for the heat-generating electronic components 3, the board 4, and the heat sink 8 in the third embodiment described below, the shortest ventilation path Fc for cooling air is secured, thereby improving the heat dissipation effect.

[0017] This allows for a heat dissipation effect through natural air cooling without the need for a driving part such as a fan, thereby reducing the number of parts and simplifying the manufacturing process. Meanwhile, up to this point we have explained heat dissipation, but from here on we will explain waterproofing while ensuring the above heat dissipation. As explained in the background art, even when electronic device 1 is installed in a vehicle cabin, water droplets may drip onto the electronic device, not only from drinking water dropped by passengers but also from condensation from an air conditioning unit, for example.

[0018] Therefore, in the electronic device 1 of the present disclosure, the cover 21 and the housing 22 are made of waterproof materials that are machined or molded from resin materials such as PBT (Polybutylene Terephthalate), PC (Polycarbonate), PP (Polypropylene), ABS (Acrylonitrile Butadiene Styrene) resin, acrylic, or metals such as aluminum and stainless steel. A seal member 2s made of rubber or the like is sandwiched between the two parts and fastened with screws to eliminate any gaps between the cover 21 and the housing 22, thereby ensuring waterproofing.

[0019] Meanwhile, the internal space S2 of the housing 2 is in communication with the outside air through an intake port 2i and an exhaust port 2x (collectively referred to as ventilation ports) located at different positions above and below the housing 2. However, the intake port 2i is provided to open from the bottom surface 2fb from the interior of the housing 2 toward approximately the downward direction, making it unlikely that water droplets will enter due to gravity. In addition, the exhaust port 2x, located above the electronic components 3, is provided to open from the rear surface (side surface 2fs) from the interior of the housing 2 in a direction perpendicular to the vertical direction (z), making it unlikely that water droplets will enter due to simple water droplets falling.

[0020] However, in an in-vehicle environment, water droplets do not necessarily fall from directly above, but may proceed toward the housing 2 from various angles depending on the flow of outside air or the driving conditions. Therefore, in the electronic device 1 of the first embodiment, a water-repellent ventilation filter 5, for example a mesh-like ventilation filter, which does not allow water droplets to pass through but does not obstruct the airflow, is provided in the ventilation hole as a waterproofing mechanism.

[0021] The ventilation filter 5 is obtained by molding a water-repellent material with low surface free energy, such as a resin material such as a fluororesin typified by PTFE (polytetrafluoroethylene), into a mesh shape using a mold to provide breathability, as shown in FIG. 3. Alternatively, the ventilation filter 5 can be formed by coating the surface of a mesh made of a metal such as stainless steel with PTFE resin. Alternatively, the ventilation filter 5 may be a nonwoven fabric or a porous sheet with holes that penetrate through the thickness direction and are distributed throughout the surface. The ventilation filter 5 can then be attached to the ventilation opening by gluing it to the ventilation opening, or by welding it if the housing 22 is made of resin, so that there are no gaps between the ventilation opening and the periphery, thereby ensuring waterproofing of the housing.

[0022] Here, the ventilation filter 5 can improve the ventilation volume by reducing the diameter (wire diameter Wf) of the fibers 5f and increasing the mesh size Wa, and the required ventilation volume can be ensured by adjusting the wire diameter Wf and mesh size Wa. Note that, depending on the mounting layout of the electronic device 1, even if water droplets poured from above run down the wall surface, pass through the ventilation holes, and adhere to the ventilation filter 5, they will not enter the interior of the housing, so waterproofing of the interior of the housing can be achieved by increasing the wire diameter and reducing the mesh size according to the particle size of the intruding water droplets.

[0023] In this example, the normal to the opening surface of the exhaust port 2x (filter surface 5ff: Figure 4) is horizontal, but to reduce air flow resistance during gravity ventilation, it is desirable for the opening surface (normal to the opening surface) to face as upward as possible. Even if the filter surface 5ff were facing directly upward in the vertical direction, dripping water would remain on the filter surface 5ff and would not enter the housing.

[0024] However, if water droplets remain on the filter surface 5ff, they become an obstacle, preventing the breathability expected from the mesh opening Wa, making it difficult to ensure heat dissipation. In this case, for example, if a forced cooling configuration using a fan is used, it is possible to blow off the water droplets remaining on the filter surface. However, if temperature difference ventilation is used, as in the electronic device 1 disclosed herein, it is difficult to blow off the water droplets remaining on the filter surface 5ff.

[0025] Therefore, in the electronic device 1 of the first embodiment, at least for the exhaust port 2x, the angle of the filter surface 5ff (the angle of the normal to the filter surface 5ff with respect to the vertical direction) is set to be larger than the water droplet sliding angle α, as shown in Fig. 4. In this case, it is desirable that the height of the portion of the outer surface of the housing 2 (for example, the top surface 2ft) that continues to the tip of the downward slope of the filter surface 5ff is lower than the filter surface 5ff. This allows the water droplets to slide along the filter surface 5ff and outward from the filter surface 5ff, so the opening of the exhaust port 2x is not narrowed, ensuring airflow and maintaining heat dissipation.

[0026] The ventilation filter 5 can also be attached indirectly, rather than directly, to the housing 2. For example, waterproofing can also be ensured by bonding or welding the ventilation filter 5 tightly to a relay part (not shown) made of resin or the like and having communicating holes, and then sandwiching a packing or the like between the relay part and the housing 2 to attach the relay part to the housing 2 without any gaps.

[0027] Variant. In the above example, the configuration of the exhaust port and filter was described as a waterproof mechanism for preventing water droplets from entering and remaining at the exhaust port. In the present modified examples (first modified example and second modified example), an example is described in which a structure for preventing water droplets from entering is formed at the peripheral portion of an exhaust port that opens with its normal oriented horizontally or downward from the horizontal. Fig. 5A is a partial cross-sectional view taken along line CC in Fig. 2A as a side view from the right side to illustrate the structure of the exhaust port portion of an electronic device according to the first modified example, and Fig. 5B is a partial cross-sectional view taken along line CC in Fig. 2A as a side view from the right side to illustrate the structure of the exhaust port portion of an electronic device according to the second modified example.

[0028] 5A, the electronic device 1 according to the first modification has a groove 2g formed on the rear surface 2fs to surround an exhaust port 2x that opens with its normal facing horizontally or downward from the horizontal. The groove 2g is formed with a narrow width to exert capillary action, and by capillary action, it captures water droplets that flow along the rear surface 2fs toward the exhaust port 2x, thereby preventing them from entering the exhaust port 2x.

[0029] As shown in Fig. 5B, the electronic device 1 according to the second modification has a canopy 2v protruding from the rear surface 2fs above an exhaust port 2x that opens directly to the side within the rear surface 2fs, in an area that encompasses the opening area of ​​the exhaust port 2x on both sides (x direction). This deflects water droplets that flow from above along the rear surface 2fs toward the exhaust port 2x to the outside (left and right) of the exhaust port 2x, preventing them from entering the exhaust port 2x. Note that, although this modification has been described as being used in combination with a ventilation filter 5 as a waterproofing mechanism, the ventilation filter 5 need not be used.

[0030] Embodiment 2 In the second embodiment, an example will be described in which an airflow guide is provided inside the housing to guide the airflow. Fig. 6 is a cross-sectional view of the electronic device according to the second embodiment, corresponding to Fig. 2A used to explain the configuration of the first embodiment, as viewed from the front. Note that the configuration other than the airflow guide is the same as that of the first embodiment, and therefore the description of the similar parts will be omitted and Figs. 1, 3 to 5B used in the first embodiment will be used.

[0031] 6, the electronic device 1 according to the second embodiment has wall-like airflow guides 6 disposed above and below the imaginary line Lix on the inner surface of the housing 2. The wall-like airflow guides 6 protrude in the front-to-rear direction (y direction) and extend parallel to and spaced from the imaginary line Lix in the xz plane. That is, the airflow guides 6 are disposed so as to sandwich the electronic components 3 and the board 4, which are heat-generating bodies, from above and below.

[0032] This allows the entire space inside the housing (internal space 2s) to be separated as a ventilation path Fc along the imaginary line Lix between the ventilation holes, narrowing the space to the area that includes the electronic components 3 and the board 4, thereby reducing stagnation of air in the upper part of the internal space 2s and improving the heat dissipation effect. Of course, even if there is no ventilation guide 6, the entire internal space 2s does not necessarily become the ventilation path Fc, but the presence of the ventilation guide 6 makes it possible to set the optimal area in the internal space 2s as the ventilation path Fc.

[0033] The airflow guide 6 may be integrally molded with the housing 22, or may be a separate part molded from resin or metal (not shown) attached with screws, etc. Furthermore, the airflow guide 6 has at least a portion of a surface that is approximately parallel to the imaginary line Lix, thereby forming a ventilation path Fc along a flow path that connects the intake port 2i and the exhaust port 2x, which are connected by the imaginary line Lix, via the shortest route, thereby stabilizing the airflow and further improving the heat dissipation effect.

[0034] The airflow guides 6 are formed on both the upper and lower sides of the imaginary line Lix, but the above effect can be achieved with just the upper airflow guide 6. However, since the airflow guide 6 is also formed on the lower side, the ventilation path Fc along the flow path that connects the intake port 2i and the exhaust port 2x, which are connected by the imaginary line Lix, via the shortest route can be formed in a more limited space, further stabilizing the airflow.

[0035] Variant. In the above example, an example in which a linear airflow guide is provided has been described. In this modified example, an example in which an airflow guide that extends while bending with respect to an imaginary line will be described. Fig. 7 is a cross-sectional view of the front view corresponding to Fig. 6, illustrating the configuration of an electronic device according to the modified example.

[0036] As shown in Fig. 7, the electronic device 1 according to the modified example is bent so that the gap between the upper and lower airflow guides 6 narrows above the board 4. This increases the driving force for removing heat from the heat-generating electronic components 3 and board 4, and the rising air temperature, resulting in better heat dissipation. Although not shown, the airflow guides 6 may be partially cut out.

[0037] Embodiment 3 In the third embodiment, an example in which a heat sink is provided to increase heat dissipation from an electronic device will be described. Figures 8A and 8B are provided to explain the configuration of an electronic device according to the third embodiment, where Figure 8A is a cross-sectional view in front view corresponding to Figure 2A used to explain the first embodiment, and Figure 8B is a cross-sectional view taken along line DD in Figure 8A as a side view of the electronic component portion from diagonally above to the right. Note that, apart from the provision of a heat sink, the electronic device is the same as in the first embodiment, and therefore, a description of similar parts will be omitted and Figures 1, 3 to 5B used in the first embodiment will be used.

[0038] 8A and 8B, the electronic device 1 according to the third embodiment includes a heat sink 8 that directly or indirectly transfers heat from a heat-generating electronic component 3. The heat sink 8 is preferably made of a metal material with high thermal conductivity, such as aluminum or copper, and is shaped by cutting or the like.

[0039] The heat sink 8 is fastened to a fixing boss 22b formed to protrude from the inner surface 2fi of the housing 22 with an unnumbered screw in place of the substrate 4, and is disposed at a position where the imaginary line Lix passes. Unlike the embodiment, the electronic component 3 is mounted on the rear surface of the substrate 4, and is screwed to an unnumbered boss protruding from the heat sink 8 to the front surface.

[0040] Meanwhile, unreferenced bosses protruding toward the front surface are formed from the four corners of the heat sink 8 in the xz plane, and the four corners of the substrate 4 are fixed with unreferenced screws. Meanwhile, the electronic component 3 mounted on the rear surface of the substrate 4 is in contact with the part protruding from the center part in the xz plane of the heat sink 8 via the heat transfer material 9. The heat transfer material 9 may be a silicone sheet type or an adhesive curing type.

[0041] This allows heat from the electronic component 3 to be indirectly transferred from the package (not shown) of the electronic component 3 to the heat sink 8 via the heat transfer material 9. The heat sink 8 is disposed at a position where the imaginary line Lix connecting the intake port 2i and the exhaust port 2x passes, i.e., in the flow path of the cooling air, thereby improving the cooling effect. Note that the package may be in contact with the heat sink 8, thereby directly transferring heat from the heat-generating electronic component 3.

[0042] Variant. In this modified example, an example in which fins are provided on a heat sink will be described. Figures 9A and 9B are diagrams for explaining the configuration of an electronic device according to this modified example, with Figure 9A being a cross-sectional view in front view corresponding to Figure 8A, and Figure 9B being a cross-sectional view taken along line EE in Figure 9A as a side view of the electronic component portion from diagonally above to the right.

[0043] 9A and 9B, the electronic device 1 according to the modified example has fins 8f formed on the surface of the heat sink 8 facing the inner surface 2fi of the housing 22, protruding toward the inner surface 2fi. The fins 8f are arranged at intervals along a direction substantially parallel to the imaginary line Lix. This increases the heat transfer area from the electronic component 3 to the air via the heat sink 8 without impeding the airflow, thereby further improving heat dissipation.

[0044] Embodiment 4 In this third embodiment, an example will be described in which a radar device having a plurality of transmitting antennas and receiving antennas is configured as an electronic device. Figures 10 and 11 are provided to explain the configuration of a radar device as an electronic device according to a fourth embodiment, with Figure 10 being a front view of a radar portion in which a plurality of transmitting antennas and receiving antennas are arranged in a plane, and Figure 11 being a cross-sectional view of an electronic component portion as seen from a diagonally upward side corresponding to Figure 9B, for explaining the configuration of a radar device according to a modified example.

[0045] Note that, apart from the configuration of the radar device, the present embodiment is similar to the first to third embodiments, and therefore, explanations of similar parts will be omitted and Figures 1 to 5B used in the first embodiment, Figures 6 and 7 of the second embodiment, and Figure 9A of the third embodiment will be used.

[0046] Automotive radar detects targets by transmitting radio waves and receiving reflected waves from the target. Radio waves are transmitted in frequency bands known as millimeter waves, such as the 24 GHz, 77 GHz, and 81 GHz bands. Automotive radar uses multiple transmitting antennas (TX) and multiple receiving antennas (RX), and the main body is installed in an upright position parallel to the target so that the antennas face the target, such as a car or roadside object. This makes it possible to obtain information on the distance to the target as well as its direction based on signal processing.

[0047] 10 shows an example of an antenna substrate for use as the substrate 4 in an antenna configuration with four-channel transmitting antennas TX1 to TX4 (collectively referred to as transmitting antennas TX) and four-channel receiving antennas RX1 to RX4 (collectively referred to as receiving antennas RX). In this example, a monolithic microwave integrated circuit (MMIC), which is a high-frequency element, is mounted on the substrate 4 as the electronic component 3. Each transmitting antenna TX and each receiving antenna RX on the substrate 4 are configured to couple radio waves with ports formed on the electronic component 3 that correspond to each antenna.

[0048] The electronic component 3, which is a high-frequency element, and each antenna are connected by a circuit pattern such as a microstrip line. In this case, for example, a patch antenna formed with a copper foil pattern on a high-frequency substrate is used as the antenna. The high-frequency element is packaged and integrated with semiconductor devices that perform radar processing, such as generating, transmitting, and receiving radio waves. However, since there are parts within the package that generate high amounts of heat, heat generation has become a problem, leading to reduced output, increased noise, reduced radar detection performance, and even reduced reliability.

[0049] Therefore, in order to realize a radar with good detection capabilities, efficient heat dissipation is required, and by applying the electronic device 1 disclosed herein, which combines cooling performance and waterproofing, to a radar device, a highly reliable radar device can be obtained.

[0050] Variant. In the above example, the electronic component 3 as a high-frequency element, the transmitting antenna TX, and the receiving antenna RX are integrally mounted on the substrate 4 as an antenna substrate, but the present invention is not limited to this. As shown in Fig. 11 of this modified example, the transmitting antenna TX, the receiving antenna RX, and their connecting parts to the substrate 4 may be mounted on a plane parallel to the substrate 4 on which the electronic component 3 as a high-frequency element and their connecting parts to the transmitting antenna TX and the receiving antenna RX are mounted, and the connecting parts to the substrate 4 may be mounted as separate components 10 such as waveguides by screwing, soldering, or the like.

[0051] In this case, the transmitting antenna TX and receiving antenna RX may be patch antennas formed with a copper foil pattern on a high-frequency substrate, as in the integrated type, or may be waveguide antennas in which metal surface components are laminated and bonded with a conductive adhesive or the like.

[0052] Although various exemplary embodiments and examples are described in this disclosure, the various features, aspects, and functions described in one or more embodiments are not limited to the application of a particular embodiment, but may be applied to the embodiments alone or in various combinations. Therefore, countless modifications not illustrated are contemplated within the scope of the technology disclosed in this specification. For example, this includes cases where at least one component is modified, added, or omitted, or where at least one component is extracted and combined with components of another embodiment.

[0053] For example, in the present disclosure, an example has been shown in which the ventilation filter 5 is provided at both the intake port 2i and the exhaust port 2x, but this is not limited to this, and it is sufficient that the ventilation filter 5 is provided at least at the exhaust port 2x located above the electronic component 3.

[0054] As described above, the electronic device 1 of the present disclosure is configured such that the electronic component 3 is housed in the internal space S2, and the housing 2 is provided with the air intake 2i, which opens below the electronic component 3 in the vertical direction (z direction) when installed, communicating the external air with the internal space S2, and the air exhaust 2x, which opens above the electronic component 3, communicating the external air with the internal space S2. The housing 2 also includes a ventilation path Fc for the cooling air for the electronic component 3, which is formed in the internal space S2 from the air intake 2i to the air exhaust 2x, driven by an ascending air current driven by the heat of the electronic component 3. The housing 2 also includes a waterproofing mechanism (ventilation filter 5, eaves 2v, and groove 2g) that maintains the ventilation of the cooling air and prevents water droplets falling from above from entering the internal space S2 through the air exhaust 2x. This allows the housing 2 to achieve both waterproofing and heat dissipation without using a fan.

[0055] In particular, as a waterproofing mechanism, a ventilation filter 4 is provided which covers the exhaust port 2x, repels water droplets, and allows cooling air to pass through. If the surface of the exhaust port 2x facing the outside air is tilted from directly above in the vertical direction (z direction) by an angle α or more at which water droplets slide off the ventilation filter 5, the water droplets slide downward on the filter surface 5ff and are expelled outside the range of the ventilation filter 5, so ventilation is not hindered and high heat dissipation performance can be maintained.

[0056] Furthermore, the surface of the exhaust port 2x facing the outside air opens with its normal facing horizontally or downward from the horizontal, and the outer surface of the housing 2 is provided with at least one of a canopy 2v provided above the exhaust port 2x and a groove 2g surrounding the exhaust port 2x as a waterproofing mechanism, which prevents water droplets running along the outer surface of the housing 2 from approaching the exhaust port 2x, thereby not impeding ventilation and maintaining high heat dissipation performance.

[0057] Furthermore, if the intake port 2i and the exhaust port 2x are arranged to open on different surfaces of the housing 2, it is possible to prevent water droplets from directly hitting the electronic components 3 through the ventilation openings.

[0058] If the electronic component 3 is positioned closer to the straight line (imaginary line Lix) connecting the center position Pi of the air intake port 2i and the center position Px of the air exhaust port 2x than to the upper and lower end portions of the internal space S2, the air will be able to reach the electronic component 3 efficiently, improving heat dissipation.

[0059] If the housing 2 is provided with airflow guides 6 that are spaced apart in the vertical direction (z direction) relative to the straight line (imaginary line Lix) and that narrow the area of ​​the ventilation path Fc in the internal space S2, heat buildup is prevented and the air is efficiently directed at the electronic components 3, improving heat dissipation.

[0060] By providing a board 4 on which electronic components 3 are mounted and which is set so as to extend in a plane including a vertical line along the ventilation path Fc, air flows smoothly along the board 4, improving heat dissipation.

[0061] If a heat sink 8 is provided in the ventilation path Fc to transfer heat from the electronic components 3, the heat dissipation performance can be further improved.

[0062] In particular, if the heat sink 8 is provided with fins 8f extending along the ventilation path Fc, the heat dissipation performance is further improved.

[0063] Furthermore, if the electronic device 1 is provided with an antenna having multiple transmitting antennas TX and multiple receiving antennas RX, and the electronic component 3 is provided with a high-frequency element (MMIC) having ports for coupling radio waves with each of the multiple transmitting antennas TX and the multiple receiving antennas TX, and is configured to function as a radar device, a highly reliable radar device can be obtained using a high-frequency element that generates a lot of heat.

[0064] Various aspects of the present disclosure are summarized below as appendices.

[0065] (Appendix 1) a housing that accommodates electronic components in an internal space, the housing having an air intake port that opens at a position below the electronic components in a vertical direction when installed to communicate with outside air and the internal space, and an air exhaust port that opens at an upper position to communicate with outside air and the internal space, the housing having an airflow path for cooling air for the electronic components that runs from the air intake port to the air exhaust port in the internal space by an ascending air current driven by heat from the electronic components; a waterproof mechanism that maintains the ventilation of the cooling air and prevents water droplets falling from above from entering the internal space through the exhaust port; An electronic device comprising:

[0066] (Appendix 2) As the waterproofing mechanism, a ventilation filter is provided to cover the exhaust port, repel water droplets, and allow the cooling air to pass through; The electronic device described in Appendix 1, characterized in that the surface of the exhaust port facing the outside air is inclined with respect to directly above in the vertical direction by an angle greater than the sliding angle of water droplets onto the ventilation filter.

[0067] (Appendix 3) The surface of the exhaust port facing the outside air is open with its normal line directed horizontally or downward from the horizontal, The electronic device described in Appendix 1 or 2, characterized in that the outer surface of the housing is provided with at least one of a canopy above the exhaust port and a groove surrounding the exhaust port as the waterproofing mechanism.

[0068] (Appendix 4) 4. The electronic device according to claim 1, wherein the intake port and the exhaust port are open on different sides of the housing.

[0069] (Appendix 5) The electronic device described in any one of appendixes 1 to 4, characterized in that the electronic component is positioned closer to a line connecting the center position of the intake port and the center position of the exhaust port than to the upper and lower end portions of the internal space.

[0070] (Appendix 6) The electronic device described in Appendix 5 is characterized in that the housing is provided with an airflow guide arranged at a vertical interval relative to the straight line and narrowing the area of ​​the ventilation path in the internal space.

[0071] (Appendix 7) 7. The electronic device according to any one of claims 1 to 6, comprising a substrate on which the electronic components are mounted and which is installed so as to extend in a plane including a vertical line along the ventilation path.

[0072] (Appendix 8) 8. The electronic device according to any one of claims 1 to 7, further comprising a heat sink disposed in the ventilation path for transferring heat from the electronic component.

[0073] (Appendix 9) 9. The electronic device according to claim 8, wherein the heat sink is formed with fins extending along the ventilation path.

[0074] (Appendix 10) an antenna formed with a plurality of transmitting antennas and a plurality of receiving antennas; the electronic component includes a high-frequency element having ports for coupling radio waves to the plurality of transmitting antennas and the plurality of receiving antennas, 10. The electronic device according to any one of claims 1 to 9, which functions as a radar device. [Explanation of symbols]

[0075] 1: electronic device (radar device), 2: housing, 2g: groove, 2i: air intake, 2v: eaves, 2x: exhaust port, 3: electronic component (high frequency element), 4: circuit board (antenna circuit board), 5: ventilation filter, 5ff: filter surface (surface facing the outside air), 6: airflow guide, 8: heat sink, 8f: fin, 10: separate part (waveguide), Fc: ventilation path, Lix: imaginary line, Pi: center position (of air intake), Px: center position (of exhaust port), RX: receiving antenna, S2: internal space, TX: transmitting antenna, α: sliding angle.

Claims

1. a housing that accommodates electronic components in an internal space, the housing having an air intake port that opens at a position below the electronic components in a vertical direction when installed to communicate with outside air and the internal space, and an air exhaust port that opens at an upper position to communicate with outside air and the internal space, the housing having an airflow path for cooling air for the electronic components that runs from the air intake port to the air exhaust port in the internal space by an ascending air current driven by heat from the electronic components; a waterproof mechanism that maintains the ventilation of the cooling air and prevents water droplets falling from above from entering the internal space through the exhaust port; An electronic device comprising:

2. As the waterproofing mechanism, a ventilation filter is provided to cover the exhaust port, repel water droplets, and allow the cooling air to pass through; 2. The electronic device according to claim 1, wherein the surface of the exhaust port facing the outside air is inclined with respect to directly above in the vertical direction by an angle equal to or greater than an angle at which water droplets slide off the ventilation filter.

3. The surface of the exhaust port facing the outside air is open with its normal line directed horizontally or downward from the horizontal, 2. The electronic device according to claim 1, wherein the outer surface of the housing is provided with at least one of a canopy provided above the exhaust port and a groove surrounding the exhaust port as the waterproofing mechanism.

4. 4. The electronic device according to claim 1, wherein the intake port and the exhaust port are opened on different surfaces of the housing.

5. 4. The electronic device according to claim 1, wherein the electronic component is positioned closer to a line connecting the center position of the intake port and the center position of the exhaust port than to the upper and lower end portions of the internal space.

6. 6. The electronic device according to claim 5, wherein the housing is provided with an airflow guide arranged at a distance in a vertical direction relative to the straight line, the airflow guide narrowing the area of ​​the ventilation path in the internal space.

7. 4. The electronic device according to claim 1, further comprising a substrate on which the electronic components are mounted and which is disposed so as to extend in a plane including a vertical line along the ventilation path.

8. 4. The electronic device according to claim 1, further comprising a heat sink disposed in the ventilation path for transferring heat from the electronic component.

9. 9. The electronic device according to claim 8, wherein the heat sink is formed with fins extending along the ventilation path.

10. an antenna formed with a plurality of transmitting antennas and a plurality of receiving antennas; the electronic component includes a high-frequency element having ports for coupling radio waves to the plurality of transmitting antennas and the plurality of receiving antennas, 4. The electronic device according to claim 1, which functions as a radar device.

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