Electronic device

Abstract

To provide an electronic device capable of appropriately controlling a heat dissipation direction from a thin package.SOLUTION: An electronic device 1 includes a substrate 10 having a first surface 10a having a longitudinal direction and a lateral direction and heat generating components 11 and 12 located on the first surface 10a, a housing 40 having a base portion 42 and a cover portion 44 and accommodating the substrate 10 in a space defined by the base portion 42 and the cover portion 44, a heat sink 20 located between the substrate 10 and the cover portion 44 so as to overlap the heat generating components 11 and 12 and thermally connected to the heat generating components 11 and 12, and a fan 30 that is located on the first surface 10a so as to be aligned with the heat sink in the longitudinal direction and sucks air from the thickness direction and blows the air toward the heat sink 20. The cover portion 44 has at least one hole 441, 442, 443 located in a range overlapping the heat sink 20.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] Patent Document 1 discloses an electronic device that transfers heat from a chip mounted on a board to a heat sink inside a housing and cools the heat sink inside the housing with a heat dissipation fan. Patent Document 2 discloses a memory system that dissipates heat from a controller chip in a thin memory package in the thickness direction and cools it with air passing outside the package. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2019-80015 [Patent Document 2] Japanese Patent Publication No. 2023-15553 Summary of the Invention [Problem to be solved by the invention]

[0004] When cooling a heat sink with air from a heat dissipation fan inside a housing, as in the electronic device described in Patent Document 1, it is necessary to increase the thickness to increase the cross-sectional area of ​​the air passage. However, it is difficult to apply such a thick package to a thin device.

[0005] When a thin package is used for application to a thin device, such as the memory system described in Patent Document 2, it is difficult to circulate air inside the package, so heat is dissipated in the thickness direction of the package. However, heat dissipation in the thickness direction of the package tends to cause the front or back of the thin device containing the package to become hot. The temperature rise on the front or back of the thin device reduces the comfort when the user uses the thin device.

[0006] The present disclosure has been made in view of the above circumstances, and aims to appropriately control the direction of heat dissipation from a thin package. [Means for solving the problem]

[0007] According to one embodiment of the present disclosure, there is provided an electronic device (1) comprising: a substrate having a first surface having a longitudinal direction and a lateral direction and a heat-generating component located on the first surface; a housing having a base and a cover extending along the first surface and accommodating the substrate in a space defined by the base and the cover; a heat sink positioned between the substrate and the cover and overlapping the heat-generating component in a plan view of the first surface and thermally connecting the heat-generating component; and a fan positioned alongside the heat sink in the longitudinal direction on the first surface, drawing in air from a thickness direction intersecting the first surface and blowing it toward the heat sink. The heat sink includes a flat surface positioned at a predetermined distance from the cover. The cover has at least one hole positioned in an area overlapping the heat sink in a plan view of the first surface.

[0008] (2) In the electronic device described in (1) above, the cover may have one or more sets of holes, and the holes may be a combination of at least two holes positioned side by side in the short-side direction.

[0009] (3) In the electronic device described in (2) above, the one or more sets of mounting holes may be located closer to the fan than a position in the longitudinal direction where at least a portion of the heat-generating component is mounted.

[0010] (4) In the electronic device described in (2) or (3) above, the one or more sets of holes may include at least one set of first holes located closer to the fan in the longitudinal direction and at least one set of second holes located farther from the fan.

[0011] (5) In the electronic device described in (4) above, the second holes may be two long holes positioned symmetrically in the short side direction and having a long axis that points outward in the short side direction as it moves away from the fan along the longitudinal direction.

[0012] (6) In the electronic device described in (4) or (5) above, the cover portion may further include a third hole located between the heat sink and the fan in the longitudinal direction.

[0013] (7) In the electronic device described in any one of (2) to (6) above, the further the longitudinal position of each of the plurality of sets of hole combinations is from the fan, the larger the sum of the opening areas of the holes included in each of the plurality of sets of hole combinations may be.

[0014] (8) In the electronic device described in any one of (1) to (7) above, the heat-generating component may include a first heat-generating component and a second heat-generating component. The heat sink may have a first heat sink to which heat generated by the first heat-generating component is conducted, a second heat sink to which heat generated by the second heat-generating component is conducted, and a slit separating the first heat sink and the second heat sink at least at the center in the short-side direction. In a plan view of the first surface of the substrate, at least a portion of the hole and at least a portion of the slit may be positioned to overlap. [Effects of the Invention]

[0015] An electronic device according to an embodiment of the present disclosure can appropriately control the direction of heat dissipation from a thin package. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a perspective view illustrating an example of the configuration of an electronic device according to an embodiment. [Figure 2] FIG. 2 is a perspective view showing the cover portion in FIG. 1 in a see-through manner. [Figure 3] FIG. 2 is an exploded perspective view of a base, a substrate, a heat conduction member, and a heat sink. [Figure 4] FIG. 3 is a plan view of FIG. 2. [Figure 5] 5 is a cross-sectional view taken along the line AA in FIG. 4. [Figure 6] FIG. 5 is a plan view showing the heat sink in FIG. 4 in a transparent manner. DETAILED DESCRIPTION OF THE INVENTION

[0017] An electronic device is configured to be able to dissipate heat generated inside the housing. When the housing of an electronic device is thin, the direction in which the heat generated inside the housing is conducted and dissipated can be the thickness direction of the thin housing or the planar direction of the thin housing.

[0018] When heat generated inside the housing of an electronic device is conducted in the thickness direction of the thin housing, the temperature of the front or back surface of the thin housing rises. Here, users of the electronic device often touch the front or back surface of the thin housing when using the electronic device. The rise in temperature of the front or back surface of the thin housing reduces the comfort of the user when using the electronic device.

[0019] When heat generated inside the housing of an electronic device is conducted in the planar direction of the thin housing, the temperature of the front or back surface of the thin housing is less likely to rise. However, because the housing is thin, the cross-sectional area along the thickness direction of the housing is small. This small cross-sectional area increases the thermal resistance when conducting heat in the planar direction of the housing. If a thin heat sink is simply used to fit the thin housing, it is difficult to efficiently conduct heat in the planar direction of the housing.

[0020] According to the electronic device according to the present disclosure, heat can be efficiently conducted in the planar direction of the housing inside the thin housing of the electronic device.

[0021] The electronic device according to the present disclosure is assumed to be realized as an SSD (Solid State Drive). The electronic device is not limited to an SSD, and may be realized as a thin device with limited external dimensions, such as a server blade or a storage blade. The electronic device may be realized as a device based on the M.2 standard. The electronic device is not limited to these examples, and may be realized as various thin devices that require heat dissipation.

[0022] (Configuration example of electronic device 1) 1 to 6, an electronic device 1 according to an embodiment of the present disclosure includes a substrate 10, a heat sink 20, a fan 30, and a housing 40. The electronic device 1 is connected to an external connector 50.

[0023] As shown in FIGS. 1 and 2, the housing 40 has a base portion 42 and a cover portion 44. The housing 40 is configured by combining the base portion 42 and the cover portion 44, and has a rectangular parallelepiped outer shape. Specifically, the dimension of the outer shape of the housing 40 in the Z-axis direction is shorter than the dimension in the planar direction extending along the XY plane. In other words, the housing 40 has a thin outer shape. Furthermore, the dimension of the housing 40 in the X-axis direction is longer than the dimension in the Y-axis direction. In the present disclosure, the X-axis direction is also referred to as the longitudinal direction of the housing 40. The Y-axis direction is also referred to as the lateral direction of the housing 40. Furthermore, the Z-axis direction is also referred to as the thickness direction of the housing 40.

[0024] As shown in FIG. 5 , the base portion 42 has a base plane 421 and base side surfaces 422 that protrude in the positive direction of the Z axis from both ends of the base plane 421 in the Y axis direction. The cover portion 44 has a cover plane 444 and cover side surfaces 445 that protrude in the negative direction of the Z axis from both ends of the cover plane 444 in the Y axis direction. The base portion 42 and the cover portion 44 are U-shaped in cross section along the YZ plane. The housing 40 has an internal space partitioned by the base portion 42 and the cover portion 44, with the side of the base portion 42 from which the base side surface 422 protrudes facing the side of the cover portion 44 from which the cover side surface 445 protrudes. The housing 40 has a cylindrical shape with a central axis along the X axis direction, due to the base portion 42, the cover portion 44, and the internal space.

[0025] As shown in FIG. 2, the substrate 10 is accommodated in the internal space of the housing 40. The substrate 10 has a first surface 10a and a second surface 10b extending along the XY plane. As shown in FIG. 5, the first surface 10a faces the cover portion 44, and the second surface 10b faces the base portion 42. As shown in FIG. 4, the dimensions of the first surface 10a and the second surface 10b in the X-axis direction are longer than the dimensions in the Y-axis direction. That is, the longitudinal direction of the substrate 10 coincides with the longitudinal direction of the housing 40, and the lateral direction of the substrate 10 coincides with the lateral direction of the housing 40. Furthermore, the thickness direction of the substrate 10 coincides with the thickness direction of the housing 40 and intersects with the first surface 10a. The substrate 10 is a plate-like member having a shape that fits the internal space of the housing 40. Conversely, the base portion 42 and the cover portion 44 of the housing 40 are configured so that the shape of the internal space of the housing 40 matches the shape of the substrate 10.

[0026] As shown in FIGS. 3 and 6 , a first heat-generating component 11 and a second heat-generating component 12 are mounted on the first surface 10a of the substrate 10. The first heat-generating component 11 and the second heat-generating component 12 are located on the negative X-axis side of the first surface 10a of the substrate 10. That is, the first heat-generating component 11 and the second heat-generating component 12 illustrated in the present disclosure are located offset toward one longitudinal end of the first surface 10a of the substrate 10. The positions of the first heat-generating component 11 or the second heat-generating component 12 are not limited to the illustrated positions and may be any longitudinal position. When the first heat-generating component 11 and the second heat-generating component 12 are energized and operating, heat is generated in the first heat-generating component 11 and the second heat-generating component 12. In this embodiment, the heat generation amount of the second heat-generating component 12 is greater than the heat generation amount of the first heat-generating component 11. The second heat-generating component 12 is mounted on the first surface 10a of the substrate 10 closer to the negative X-axis side than the first heat-generating component 11. The first heat generating component 11 and the second heat generating component 12 are also collectively referred to as heat generating components.

[0027] The first heat-generating component 11 mounted on the substrate 10 includes a nonvolatile memory such as a NAND flash memory. The first heat-generating component 11 may also include a volatile memory such as a DRAM (Dynamic Random Access Memory). The first heat-generating component 11 may also include a power management element for controlling the power consumption of the electronic device 1. The second heat-generating component 12 mounted on the substrate 10 may also include a processor such as a CPU (Central Processing Unit) that controls the reading and writing of data to the NAND flash memory. The second heat-generating component 12 may also include a dedicated circuit for controlling the electronic device 1, such as an FPGA (Field-Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit).

[0028] The substrate 10 may be configured as a so-called printed circuit board. The substrate 10 may include, for example, solder resist as a material. The substrate 10 may include various materials other than the exemplified materials. The substrate 10 may be configured to have low thermal conductivity in the direction along the first surface 10a. If the thermal conductivity of the substrate 10 in the direction along the first surface 10a is low, heat generated in the second heat-generating component 12 is less likely to be conducted to the first heat-generating component 11 through the substrate 10. The substrate 10 may also be configured so that the sum of the amount of heat conducted from the second heat-generating component 12 to the heat sink 20 and the amount of heat removed from the second heat-generating component 12 by the wind from the fan 30 is greater than the amount of heat conducted from the second heat-generating component 12 to the first heat-generating component 11.

[0029] Other components different from the first heat-generating component 11 or the second heat-generating component 12 may be mounted on the first surface 10a of the substrate 10. The other components may also be mounted on the second surface 10b of the substrate 10. The other components may be components that generate heat or components that do not generate heat. The other components may be mounted in any position on the substrate 10 in any layout. The other components may be mounted on the positive side of the X-axis relative to the first heat-generating component 11 or the second heat-generating component, or may be mounted on the negative side of the X-axis relative to the first heat-generating component 11 or the second heat-generating component.

[0030] 1 and 2, the substrate 10 is connected to an external connector 50 at its end in the negative X-axis direction. The substrate 10 may have a terminal connectable to the connector 50 at its end in the negative X-axis direction.

[0031] As shown in FIG. 2, the heat sink 20 is accommodated in the internal space of the housing 40 together with the substrate 10. As shown in FIG. 5, the heat sink 20 is positioned between the substrate 10 and the cover portion 44. As shown in FIGS. 2 to 5, the heat sink 20 has a flat portion 22, ribs 24, and bent portions 26. The flat portion 22 extends along the XY plane. The ribs 24 protrude in the positive direction of the Z axis, i.e., toward the cover portion 44, from both sides of the flat portion 22 located in the Y axis direction. The bent portions 26 protrude inward from parts of the ribs 24 along the flat portion 22. As shown in FIG. 5, when the ribs 24 of the heat sink 20 abut against the cover portion 44, the cover portion 44 and the flat portion 22 of the heat sink 20 are spaced apart by the dimension of the ribs 24 in the Z axis direction. In other words, the flat portion 22 of the heat sink 20 is positioned with a predetermined distance from the cover portion 44 corresponding to the dimension of the ribs 24 in the Z axis direction. The flat surface 22 of the heat sink 20 is positioned with a predetermined gap between it and the cover portion 44, thereby defining a space surrounded by the cover portion 44, the flat surface 22 of the heat sink 20, and the ribs 24. The space between the cover portion 44 and the flat surface 22 of the heat sink 20 communicates with the internal space of the housing 40 at both ends in the X-axis direction.

[0032] The heat sink 20 is positioned so as to overlap the first heat-generating component 11 and the second heat-generating component 12 in a plan view of the first surface 10a of the substrate 10. In other words, as also shown in Figures 2 and 3, the heat sink 20 exemplified in the present disclosure is positioned offset in the negative direction of the X-axis between the substrate 10 and the cover part 44. The position of the heat sink 20 may be any position in the longitudinal direction depending on the positions of the first heat-generating component 11 and the second heat-generating component 12.

[0033] 4, the flat surface 22 of the heat sink 20 contacts the first heat-generating component 11 and the second heat-generating component 12 via the component-side thermally conductive member 13. In other words, the flat surface 22 of the heat sink 20 is thermally connected to the first heat-generating component 11 and the second heat-generating component 12. The component-side thermally conductive member 13 may be configured to include a material with high thermal conductivity, such as a thermal interface material (TIM). The component-side thermally conductive member 13 may also be replaced with another type of material with high thermal conductivity, such as grease.

[0034] 2, the fan 30 is housed in the internal space of the housing 40 together with the substrate 10 and the heat sink 20. The fan 30 is mounted on the first surface 10a of the substrate 10. The fan 30 may not be mounted on the first surface 10a of the substrate 10, but may simply be located between the cover part 44 and the substrate 10.

[0035] The fan 30 exemplified in the present disclosure is positioned offset toward the positive X-axis direction in a plan view of the first surface 10a of the substrate 10. On the other hand, the heat sink 20 exemplified in the present disclosure is positioned offset toward the negative X-axis direction in a plan view of the first surface 10a of the substrate 10, as described above. In other words, the heat sink 20 and the fan 30 exemplified in the present disclosure are positioned offset toward opposite ends of the housing 40 in the longitudinal direction. The positional relationship of the fan 30 with respect to the heat sink 20 is not limited to the relationship exemplified in the present disclosure. The fan 30 may be positioned at any distance from the heat sink 20 in the longitudinal direction, as long as the fan 30 is positioned alongside the heat sink 20 in the longitudinal direction.

[0036] Fan 30 has an air intake port 32 and an air outlet 31. Air intake port 32 is located on the side in the positive direction of the Z axis. Cover part 44 has an opening in cover plane 444 that corresponds to air intake port 32 of fan 30. Fan 30 draws air from outside housing 40 through air intake port 32. Air outlet 31 is located on the side in the negative direction of the X axis. Fan 30 draws air through air intake port 32 and blows it out through air outlet 31, generating wind in the internal space of housing 40 in the negative direction of the X axis.

[0037] The fan 30 may be disposed at a position where the distance from the heat sink 20 in the longitudinal direction of the housing 40 is greatest within the range in which the housing 40 can accommodate the fan 30. Furthermore, when the fan 30 is mounted on the first surface 10a of the substrate 10, the fan 30 may be mounted at a position farthest from the first heat-generating component 11 and the second heat-generating component 12 in the longitudinal direction of the first surface 10a of the substrate 10 so that the distance from the heat sink 20 in the longitudinal direction of the housing 40 is greatest. As the distance between the heat sink 20 and the fan 30 in the longitudinal direction of the housing 40 increases, the airflow blown out from the air outlet 31 of the fan 30 is more likely to be rectified in line with the inlet of the heat sink 20 before flowing toward the heat sink 20. By rectifying the airflow in line with the inlet of the heat sink 20, the amount of air reflected at the inlet of the heat sink 20 and flowing backward in the positive direction of the X-axis decreases, and the amount of air flowing directly through the heat sink 20 in the negative direction of the X-axis increases. As a result, heat is efficiently removed from the heat sink 20, and the heat from the first heat-generating component 11 and the second heat-generating component 12 is dissipated in the longitudinal direction of the housing 40.

[0038] The cover portion 44 has at least one hole penetrating the cover plane 444 and connecting the internal space of the housing 40 to the outside. The hole is located at least closer to the negative X-axis direction than the air outlet 31 of the fan 30, i.e., closer to the heat sink 20. The pressure in the internal space of the housing 40 becomes higher than the external pressure when the fan 30 blows air through the air outlet 31. Here, the pressure in the internal space of the housing 40 at the position of the hole connecting the internal space of the housing 40 to the outside becomes lower than the ambient pressure. This makes it easier for air to flow toward the position of the hole in the internal space of the housing 40. By locating the hole closer to the heat sink 20 than the air outlet 31 of the fan 30, the air blown out from the air outlet 31 of the fan 30 easily flows toward the heat sink 20. The air flowing toward the heat sink 20 flows directly into the area where the heat sink 20 is located due to inertia, and easily reaches the end of the housing 40 in the negative X-axis direction.

[0039] 1, 2, and 4, the cover portion 44 has a first hole 441 and a second hole 442 that are positioned in an area that overlaps with the heat sink 20 in a plan view of the first surface 10a of the substrate 10. The cover portion 44 does not necessarily have to have either the first hole 441 or the second hole 442. In other words, the cover portion 44 has at least one hole that is positioned in an area that overlaps with the heat sink 20 in a plan view of the first surface 10a of the substrate 10.

[0040] The first holes 441 are located closer to the fan 30 than the second holes 442 in the longitudinal direction of the housing 40, within an area that overlaps with the heat sink 20 in a plan view of the first surface 10a of the substrate 10. The first holes 441 include two holes that are aligned in the Y-axis direction. The two holes serving as the first holes 441 may be located offset toward both ends in the short-side direction of the housing 40. The two holes serving as the first holes 441 may be located symmetrically in the short-side direction of the housing 40. The number of holes serving as the first holes 441 is not limited to two, and may be one, or three or more.

[0041] The second holes 442 are located farther from the fan 30 than the first holes 441 in the longitudinal direction of the housing 40, within an area that overlaps with the heat sink 20 in a plan view of the first surface 10a of the substrate 10. The second holes 442 include two holes aligned in the Y-axis direction. The two holes serving as the second holes 442 may be located offset toward both ends in the short side direction of the housing 40. The two holes serving as the second holes 442 may be located symmetrically in the short side direction of the housing 40. The number of holes serving as the second holes 442 is not limited to two, and may be one, or three or more.

[0042] Furthermore, the second holes 442 may be elongated holes having long axes. The long axes of the two elongated holes that are the second holes 442 extend in directions that move farther apart in the Y-axis direction as they move in the negative X-axis direction. In other words, the long axes of the two elongated holes that are the second holes 442 extend outward in the short-side direction as they move away from the fan 30 along the longitudinal direction. The two elongated holes that are the second holes 442 are arranged in a V-shape when viewed from above on the first surface 10a of the substrate 10.

[0043] When the first hole 441 or the second hole 442 is a combination of at least two holes, it is also referred to as a pair of holes. The cover part 44 may have one or more pairs of pair of holes. The first hole 441 or the second hole 442 may include multiple pairs of pair of holes. In other words, the first hole 441 or the second hole 442 may include at least one pair of pair of holes.

[0044] By positioning the holes in an area overlapping the heat sink 20 in a plan view of the first surface 10a of the substrate 10, the pressure in the space between the heat sink 20 and the cover portion 44 is reduced, and the air blown out from the air outlet 31 of the fan 30 is more likely to enter the space between the heat sink 20 and the cover portion 44 than the space between the heat sink 20 and the substrate 10. In other words, the airflow is more likely to pass above the heat sink 20 than below the heat sink 20. The airflow passing through the space between the heat sink 20 and the cover portion 44, i.e., above the heat sink 20, is more likely to reach the end of the housing 40 in the negative X-axis direction due to inertia. The airflow passing below the heat sink 20 is significantly affected by the shape, size, or layout of the components mounted on the substrate 10. On the other hand, the airflow passing above the heat sink 20 is not affected by the components mounted on the substrate 10. Therefore, by allowing air to pass over the heat sink 20, the amount of air that comes into contact with the heat sink 20 and flows is stabilized regardless of the components mounted on the board 10, and the amount of heat that is dissipated into the air through the heat sink 20 is stabilized.

[0045] By providing the holes as a set of holes, the distribution of the air flow rate in the short direction of the heat sink 20 can be made more uniform. In this way, the amount of heat dissipated into the air through the heat sink 20 is stabilized.

[0046] Furthermore, the second holes 442 are located closer to the fan 30 than the second heat-generating component 12 in a plan view of the first surface 10a of the substrate 10. Because the second holes 442 are located closer to the fan 30 than the second heat-generating component 12, the air flowing through the space between the heat sink 20 and the cover 44 passes through the second holes 442 and reaches directly above the second heat-generating component 12. The air that absorbs heat from the second heat-generating component 12 directly above the second heat-generating component 12 then flows due to inertia toward the negative X-axis direction of the housing 40 and exits the housing 40 from the end of the housing 40 facing the negative X-axis direction. In other words, the air that has absorbed heat from the second heat-generating component 12 and has increased in temperature is less likely to flow out of the housing 40 through the second holes 442. This increases the proportion of the heat generated by the second heat-generating component 12 that is dissipated in the longitudinal direction of the housing 40, while decreasing the proportion of the heat that is dissipated in the thickness direction of the housing 40.

[0047] Furthermore, because the second hole 442 is an elongated hole, the air flow entering the space between the heat sink 20 and the cover part 44 gathers in the center in the Y-axis direction as it travels in the negative X-axis direction, then spreads out to both ends in the Y-axis direction, before reaching the end of the housing 40 in the negative X-axis direction. By shifting the air flow in the Y-axis direction in this way, heat is efficiently removed from the heat sink 20 by the air flow.

[0048] The cover part 44 further has a third hole 443. The third hole 443 is located between the heat sink 20 and the fan 30 in the longitudinal direction of the housing 40. The third hole 443 includes two holes that are biased toward both ends in the Y-axis direction, i.e., both ends in the short direction of the housing 40. The location of the third hole 443 between the heat sink 20 and the fan 30 makes it easier for air to flow from the fan 30 toward the heat sink 20.

[0049] When the cover part 44 has multiple sets of combination holes, such as the first hole 441 or the second hole 442, the opening ratio of each of the multiple sets of combination holes may be configured to increase as the longitudinal position of each of the multiple sets of combination holes increases from the fan 30. The opening ratio of a combination hole may be calculated by dividing the sum of the opening areas of the multiple holes included in the combination hole by the area of ​​the range in which the combination holes are located. Since the opening ratio of the combination hole increases with increasing distance from the fan 30, a pressure distribution is generated in which the pressure between the heat sink 20 and the cover part 44 decreases depending on the distance from the fan 30. This pressure distribution makes it easier for the air from the fan 30 to flow between the heat sink 20 and the cover part 44, and also easier for the air to flow between the heat sink 20 and the cover part 44 to the side farther from the fan 30.

[0050] The cover part 44 may also be configured so that the sum of the opening areas of the holes included in each of the plurality of sets of holes increases as the longitudinal position of each of the plurality of sets of holes increases from the fan 30. The cover part 44 may also be configured so that the number of holes included in each of the plurality of sets of holes increases as the longitudinal position of each of the plurality of sets of holes increases from the fan 30. In these cases as well, a pressure distribution occurs such that the pressure between the heat sink 20 and the cover part 44 decreases depending on the distance from the fan 30. This pressure distribution makes it easier for the air from the fan 30 to flow between the heat sink 20 and the cover part 44, and also easier for the air to flow between the heat sink 20 and the cover part 44 to the side farther from the fan 30.

[0051] 2, 3, and 4, the flat surface portion 22 of the heat sink 20 has a first heat sink 221 and a second heat sink 222. The first heat sink 221 and the second heat sink 222 are connected at both ends in the Y-axis direction, i.e., in the short-side direction of the housing 40, but are separated from each other by a slit portion 223 located in the center of the short-side direction of the housing 40. In other words, the slit portion 223 separates the first heat sink 221 and the second heat sink 222 at least in the center of the short-side direction of the housing 40.

[0052] When the first heat sink 221 and the second heat sink 222 are connected at a portion in the short-side direction of the housing 40, the heat sink 20 is configured as an integrated component. As a result, the number of components is reduced. The first heat sink 221 and the second heat sink 222 may be completely separated from each other. When the first heat sink 221 and the second heat sink 222 are completely separated from each other, the amount of heat conducted between the first heat sink 221 and the second heat sink 222 is reduced compared to when the first heat sink 221 and the second heat sink 222 are connected at a portion.

[0053] The second heat sink 222 contacts the cover portion 44 via the cover-side thermally conductive member 14. That is, the second heat sink 222 is thermally connected to the cover portion 44. The cover-side thermally conductive member 14 may be configured to include a material with high thermal conductivity, such as TIM. The cover-side thermally conductive member 14 may be replaced with another type of material with high thermal conductivity, such as grease. The second heat sink 222, which is connected to the second heat-generating component 12 that generates a large amount of heat, is thermally connected to the cover portion 44, which facilitates heat dissipation from the second heat-generating component 12. On the other hand, the heat is not easily conducted from the second heat sink 222 to the first heat sink 221, which inhibits heat conduction from the second heat-generating component 12 to the first heat-generating component 11 via the heat sink 20.

[0054] Heat conducted from the second heat sink 222 to the cover portion 44 is conducted toward the fan 30 along the longitudinal direction of the housing 40. As described above, the fan 30 may be disposed at a position where the distance from the heat sink 20 in the longitudinal direction of the housing 40 is greatest within the range of the housing 40 that can accommodate the fan 30. The longer the distance between the heat sink 20 and the fan 30 in the longitudinal direction of the housing 40, the longer the distance that the air flowing out from the fan 30 must travel to reach a position where the air overlaps the heat sink 20 in a plan view of the first surface 10a of the substrate 10. In other words, the area of ​​the cover plane 444 of the cover portion 44 that is not occupied by the heat sink 20 and is exposed to the air flow increases. As the area of ​​the area exposed to the air on the cover plane 444 increases, the heat conducted from the second heat sink 222 to the cover portion 44 is absorbed by the air. As a result, heat from the second heat-generating component 12 is dissipated in the longitudinal direction of the housing 40.

[0055] At least a portion of the hole may be positioned so as to overlap at least a portion of the slit portion 223 of the heat sink 20 in a plan view of the first surface 10a of the substrate 10. In the electronic device 1 according to the present disclosure, as shown in Figures 2 and 4, a second hole 442 that is at least a portion of the hole is positioned so as to overlap at least a portion of the slit portion 223 of the heat sink 20 in a plan view of the first surface 10a of the substrate 10. The overlap between the hole and the irregularities of the slit portion 223 of the heat sink 20 makes it easier for turbulence such as vortices to occur in the space between the heat sink 20 and the cover portion 44, and heat is efficiently removed from the heat sink 20 by the turbulence.

[0056] 2 and 4, the shape of the slit portion 223 may be bent like a crank when viewed from above on the first surface 10a of the substrate 10, but may also be various shapes such as a straight or curved shape. The shape of the slit portion 223 may be designed appropriately depending on the arrangement of the first heat-generating component 11 and the second heat-generating component 12 mounted on the first surface 10a of the substrate 10.

[0057] If the amount of heat generated by the second heat-generating component 12 is greater than the heat generated by the first heat-generating component 11, the temperature of the second heat-generating component 12 may become higher than the temperature of the first heat-generating component 11. If the temperature of the second heat-generating component 12 becomes higher than the temperature of the first heat-generating component 11, some of the heat generated by the second heat-generating component 12 is conducted to the first heat-generating component 11 through the substrate 10. The first heat sink 221 may dissipate the heat conducted from the second heat-generating component 12 to the first heat-generating component 11. If the thermal conductivity of the substrate 10 is low, the heat generated by the second heat-generating component 12 is less likely to be conducted to the first heat-generating component 11 through the substrate 10. Since the heat is less likely to be conducted from the second heat-generating component 12 to the first heat-generating component 11, the first heat-generating component 11 is less likely to be affected by the heat generated by the second heat-generating component 12.

[0058] Regardless of the magnitude relationship between the heat generation amounts of the first heat-generating component 11 and the second heat-generating component 12, the first heat-generating component 11 and the second heat-generating component 12 are less susceptible to the influence of each other's heat generation due to the low heat conduction between the first heat-sink 221 and the second heat-sink 222. For example, if the high-temperature resistance of one of the first heat-generating component 11 and the second heat-generating component 12 is lower than that of the other, the influence of heat generated by the heat-generating component with the higher high-temperature resistance on the heat-generating component with the lower high-temperature resistance is reduced. Furthermore, if the temperature characteristics of component performance differ between the first heat-generating component 11 and the second heat-generating component 12, the influence of heat generated by one of the first heat-generating component 11 and the second heat-generating component 12 on the performance of the other component is reduced.

[0059] The increase in the amount of heat removed from second heat-generating component 12 by the wind also makes it difficult for the heat generated in second heat-generating component 12 to be conducted to first heat-generating component 11 through substrate 10. Since heat is difficult to be conducted from second heat-generating component 12 to first heat-generating component 11 through substrate 10, first heat-generating component 11 is less susceptible to the influence of the heat generated by second heat-generating component 12.

[0060] <Summary> As described above, in the electronic device 1 according to the present disclosure, air is sent to the heat sink 20 from the fan 30 located in the longitudinal direction of the housing 40 in the internal space of the thin housing 40. Furthermore, in the electronic device 1 according to the present disclosure, by providing a hole in the cover portion 44 of the housing 40 at a position corresponding to the heat sink 20, the amount of air flowing into the space between the heat sink 20 and the cover portion 44 is increased, and heat conducted from the substrate 10 housed in the internal space of the housing 40 to the heat sink 20 is efficiently removed by the air and dissipated in the longitudinal direction of the housing 40. By increasing the amount of heat dissipated in the longitudinal direction of the housing 40, the amount of heat conducted in the thickness direction of the housing 40 decreases. In this way, the electronic device 1 according to the present disclosure appropriately controls the direction of heat dissipation from the thin package.

[0061] Furthermore, by reducing the amount of heat conducted in the thickness direction of the housing 40, the front or back surface of the thin device incorporating the electronic device 1 is less likely to become hot. As a result, the user can use the thin device more comfortably.

[0062] A device according to the comparative example may be configured to simply dissipate heat in the thickness direction of a thin package. However, dissipating heat in the thickness direction causes the front or back surface of a thin device incorporating the device according to the comparative example to become hot, reducing the user's comfort when using the thin device. On the other hand, with the electronic device 1 according to the present disclosure, the heat dissipation direction is appropriately controlled, and heat is dissipated in the longitudinal direction of the thin package. As a result, the user's comfort when using a thin device incorporating the electronic device 1 according to the present disclosure is improved.

[0063] In addition, a comparative example of a device may be configured to allow air to flow from one end of the thin package to the other end in the longitudinal direction. However, because the cross-sectional area of ​​the thin package when viewed in the longitudinal direction is small, it is difficult to allow a sufficient amount of air to flow to dissipate heat from the substrate 10 housed in the thin package in the longitudinal direction. On the other hand, in the electronic device 1 according to the present disclosure, by appropriately positioning the heat sink 20 and the fan 30 and providing holes in the housing 40, a sufficient amount of air can flow to dissipate heat from the substrate 10 in the longitudinal direction. The heat dissipation direction is appropriately controlled, and heat is dissipated in the longitudinal direction of the thin package. As a result, a user can enjoy greater comfort when using a thin device incorporating the electronic device 1 according to the present disclosure.

[0064] In the above-described embodiment, the heat generation amount of the second heat generating component 12 is larger than the heat generation amount of the first heat generating component 11. The heat generation amount of the second heat generating component 12 may be the same as the heat generation amount of the first heat generating component 11, or may be smaller than the heat generation amount of the first heat generating component 11.

[0065] Although the embodiments of the present disclosure have been described based on the drawings and examples, it should be noted that those skilled in the art can make various modifications and alterations based on the present disclosure. Therefore, it should be noted that these modifications and alterations are included in the scope of the present disclosure. For example, each component can be rearranged so as not to cause a logical inconsistency, and multiple components can be combined or divided into one.

[0066] In this disclosure, the terms "first" and "second" are identifiers for distinguishing the configuration. In this disclosure, the terms "first" and "second" are identifiers for distinguishing the configuration. The numbers in the configuration can be exchanged. For example, the first heat-generating component 11 can exchange the identifiers "first" and "second" with the second heat-generating component 12. The exchange of identifiers is performed simultaneously. The configuration remains distinguishable even after the identifier exchange. The identifiers may be deleted. A configuration from which an identifier has been deleted is distinguished by a symbol. The terms "first" and "second" are used solely in this disclosure to interpret the order of the configuration or to justify the existence of an identifier with a smaller number.

[0067] In this disclosure, the X-axis, Y-axis, and Z-axis are provided for convenience of explanation and may be interchanged. The configurations according to this disclosure have been described using a Cartesian coordinate system formed by the X-axis, Y-axis, and Z-axis. The positional relationship between the components according to this disclosure is not limited to an orthogonal relationship. [Explanation of symbols]

[0068] 1 Electronic equipment 10 board (10a: 1st side, 10b: 2nd side) 11 First heat generating component 12 Second heat generating component 13 Component side heat conduction material 14 Cover side heat conductive member 20 heat sink (22: flat portion, 221: first heat sink, 222: second heat sink, 223: slit portion, 24: rib, 26: bent portion) 30 Fan (31: Air outlet, 32: Air intake) 40 Housing (42: base portion, 421: base surface, 422: base side surface, 44: cover portion, 441: first hole, 442: second hole, 443: third hole, 444: cover surface, 445: cover side surface) 50 connectors

Claims

1. a substrate having a first surface having a longitudinal direction and a lateral direction, and a heat-generating component located on the first surface; a housing having a base portion and a cover portion extending along the first surface, the housing accommodating the board in a space defined by the base portion and the cover portion; a heat sink positioned between the substrate and the cover so as to overlap the heat generating component in a plan view of the first surface and thermally connect to the heat generating component; a fan located next to the heat sink in the longitudinal direction on the first surface, the fan sucking air in a thickness direction intersecting the first surface and blowing the air toward the heat sink; Equipped with the heat sink includes a flat surface portion positioned at a predetermined distance from the cover portion, the cover portion has at least one hole positioned in a range overlapping with the heat sink in a plan view of the first surface; electronic equipment.

2. The cover portion has one or more sets of holes, The electronic device according to claim 1 , wherein the pair of holes is a combination of at least two holes positioned side by side in the short-side direction.

3. The electronic device according to claim 2 , wherein the one or more sets of mounting holes are located closer to the fan than a position in the longitudinal direction where at least a portion of the heat-generating component is mounted.

4. 3. The electronic device according to claim 2, wherein the plurality of sets of holes include at least one set of first holes located closer to the fan in the longitudinal direction and at least one set of second holes located farther from the fan.

5. 5. The electronic device according to claim 4, wherein the second holes are two elongated holes positioned symmetrically in the short-side direction and having major axes that extend outward in the short-side direction as they extend along the longitudinal direction away from the fan.

6. The electronic device according to claim 4 , wherein the cover further includes a third hole located between the heat sink and the fan in the longitudinal direction.

7. The electronic device according to claim 2 , wherein the sum of the opening areas of the holes included in each of the plurality of sets of holes increases as the positions of each of the plurality of sets of holes in the longitudinal direction are farther from the fan.

8. the heat generating component includes a first heat generating component and a second heat generating component, the heat sink has a first heat sink to which heat generated by the first heat generating component is conducted, a second heat sink to which heat generated by the second heat generating component is conducted, and a slit portion separating the first heat sink and the second heat sink at least at the center in the short side direction, In a plan view of the first surface of the substrate, at least a portion of the hole and at least a portion of the slit portion are positioned to overlap each other. The electronic device according to any one of claims 1 to 7.

Images