Fan duct and electronics

Abstract

To provide a fan duct with which good heat dissipation performance can be obtained when there is an obstacle on the leeward side of a fan that blows air to dissipate heat, and an electronic apparatus comprising the fan duct.SOLUTION: A fan duct covers a heat sink that is attached to an electronic component and a fan that blows air to the heat sink, and is provided with an intake port on the upstream side of the blowing direction of the fan and an exhaust port on the downstream side, and the fan duct comprises a branch wall and ribs. The branch wall has two plate-like parts that are continuous on both sides on the upstream side in the blowing direction of the fan, and are inclined with respect to the blowing direction to be separated from each other toward the downstream side in the blowing direction of the fan, and the branch wall is arranged inside the edge of the exhaust port. The plurality of ribs project from a surface of the branch wall opposite to the heat sink, have a crest-type, plate-like shape with an acute angle at the most projecting apex, and are provided side by side in their own thickness direction.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] SUMMARY OF THE INVENTION Embodiments of the present invention relate to a fan duct and an electronic device. [Background technology]

[0002] Conventionally, electronic devices such as PCs (Personal Computers) include components that become hot, such as CPUs (Central Processing Units). Such components are generally fitted with heat sinks for heat dissipation, and furthermore, fans and fan ducts are installed to ensure an appropriate flow of gas (air) around the heat sink (e.g., Patent Document 1), and the positions of the intake and exhaust holes of the fan duct are determined.

[0003] Depending on the amount and arrangement of components contained in the housing of the electronic device, there may be components (obstacles) located downwind of the fan that prevent the gas from passing through smoothly. This undesirably reduces heat dissipation performance. Summary of the Invention [Problem to be solved by the invention]

[0004] The problem to be solved by the present invention is to provide a fan duct that can achieve good heat dissipation performance when there is an obstacle downwind of the fan that blows air for heat dissipation, and an electronic device equipped with such a fan duct. [Means for solving the problem]

[0005] The fan duct of the embodiment includes: It has an intake port and an exhaust port, It covers the heat sink attached to the electronic component and the fan that blows air to the heat sink. cormorant The valve includes a branch wall and a rib. The fan is located between the intake port and the exhaust port. The heat sink is located between the fan and the exhaust port and has a base that contacts the electronic components and a plurality of fins that protrude from the base. The protruding direction of the fins is approximately perpendicular to the flow direction of the gas caused by the blown air. The branch wall is A pair of inclined grooves are provided on the edge of the exhaust port, are positioned inside the exhaust port, are continuous on the upstream side in the gas flow direction, and are inclined so as to move away from each other toward the downstream side. Having a plate-shaped portion do The rib protrudes from a surface of the branch wall facing the heat sink, The protruding direction is opposite to the gas flow direction,The most protruding portion has a mountain-shaped plate shape with an acute angle, and a plurality of plates are arranged side by side in the thickness direction of the plate. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a perspective view showing an example of the appearance of a fan duct according to the first embodiment. [Figure 2] FIG. 2 is a perspective view schematically illustrating an example of the structure of an electronic device to which a fan duct is attached. [Figure 3] FIG. 3 is a perspective view showing an example of a ventilation hole provided in an electronic device. [Figure 4] FIG. 4 is a plan view illustrating the shape of the fan duct. [Figure 5] FIG. 5 is a vertical cross-sectional side view illustrating the shape of the fan duct. [Figure 6] FIG. 6 is a vertical cross-sectional side view illustrating the positional relationship between the fan duct and components near the exhaust port. [Figure 7] FIG. 7 is a perspective view showing the arrangement of the exhaust ports of the fan duct attached to the electronic device. [Figure 8] FIG. 8 is a plan view showing an example of the shape of the ribs provided on the fan duct of the fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] (First embodiment) The embodiments will be described with reference to the drawings. FIG. 1 is a perspective view showing an example of the appearance of a fan duct 1 according to a first embodiment. FIG. 2 is a perspective view showing an example of the structure of an electronic device 100 to which the fan duct 1 is attached. For ease of explanation, a three-dimensional coordinate system is also shown in the drawings. In the three-dimensional coordinate system, the width direction (left-right direction) of the fan duct 1 and the electronic device 100 is defined as the X-axis direction, the depth direction (front-back direction) as the Y-axis direction, and the height direction (up-down direction) as the Z-axis direction. The positive direction of the Y-axis is the direction from the rear side to the front side of the electronic device 100, and is defined as the "forward" direction. The positive direction of the Z-axis is the direction from bottom to top.

[0008] 1, fan duct 1 has a generally box-like shape and covers heat sink 2 and fan 3 that blows air to heat sink 2. Fan 3 blows air in the negative direction (rearward) of the Y axis. An air intake 11 is provided on the upstream side of fan duct 1 in the air blowing direction of fan 3, and an air exhaust 12 is provided on the downstream side.

[0009] Hereinafter, the term "upstream side" simply refers to the upstream side (or upwind) based on the airflow direction (negative direction of the Y axis) of the fan 3. Similarly, the term "downstream side" simply refers to the downstream side (or downwind) based on the airflow direction of the fan 3.

[0010] The heat sink 2 is attached to a heat-generating electronic component. This "heat-generating electronic component" is, for example, a CPU (Central Processing Unit). The heat generated by the CPU is conducted to the heat sink 2, and the heat from the heat sink 2 is dissipated into the surrounding gas (air). This prevents malfunctions due to overheating of the CPU.

[0011] The heat sink 2 is composed of a base 21 and multiple fins 22. The fins 22 are provided upright on the base 21. The multiple fins 22 are adjacent to each other at a predetermined interval. The base 21 is in contact with the CPU, and heat from the CPU is conducted therethrough. The fins 22 dissipate the heat conducted from the base 21, which is continuous with the fins 22, into the air.

[0012] The heat sink 2 is fixed onto frames 41 to 43, which are layered at predetermined intervals, with helical springs 44 and screws 45. Between the frames 41 and 42, a motherboard 101 (see FIG. 2) is sandwiched.

[0013] The fan 3 blows air by continuously sending it in one direction with rotating blades. In this embodiment, the following are arranged in order from upstream to downstream in the airflow direction of the fan 3: intake port 11, fan 3, heat sink 2, and exhaust port 12. The gas (air) taken in by the fan 3 through the intake port 11 and sent out flows mainly around the fins 22 of the heat sink 2, removing heat from the fins 22, and is discharged from the exhaust port 12.

[0014] The fan duct 1 allows the air blown by the fan 3 to efficiently dissipate heat from the heat sink 2, improving the heat dissipation effect. Specifically, the fan duct 1 surrounds the heat sink 2, and the gas inside the fan duct 1 is replaced with gas taken in from the intake port 11 by the rotation of the fan 3, and is then pushed out from the exhaust port 12. This allows the gas around the heat sink 2 to be quickly replaced.

[0015] For the above-described function of the fan duct 1, it is desirable that there are no parts (obstacles) that obstruct exhaust air downwind of the exhaust port 12. However, depending on the size of the electronic device 100 equipped with the fan duct 1 and the arrangement of its built-in components, an obstacle may be placed downstream of the exhaust port 12.

[0016] As shown in FIG. 2, the electronic device 100 includes a motherboard 101, a CPU 102, a memory 103, a solid state drive (SSD) 104, a riser card 105, expansion boards 106 and 107 such as I / O boards, and a housing 110.

[0017] The housing 110 houses the above-mentioned components (motherboard 101, CPU 102, memory 103, SSD 104, riser card 105, and expansion boards 106 and 107 such as I / O boards).

[0018] The motherboard 101 is an example of a board on which electronic components (CPU 102 in this embodiment) are mounted, the heat of which is dissipated by the heat sink 2. The memory 103 and SSD 104 also generate heat in accordance with their operation. This heat is also dissipated by the flow of air inside the housing 110, which is created by the airflow of the fan 3.

[0019] The expansion boards 106 and 107 can also be directly connected to the motherboard 101, but in that case, the expansion boards 106 and 107 stand upright on the motherboard 101, which requires the height dimension of the housing 110 to be increased, resulting in an increase in the size of the electronic device 100. To prevent this, a riser card 105 is used.

[0020] The riser card 105 mediates the connection between the expansion boards 106, 107 and the motherboard 101. The riser card 105 has one or more slots that accept the insertion of the expansion boards 106, 107, and is inserted into the slots provided in the motherboard 101. The riser card 105 allows the expansion boards 106, 107 to be positioned and connected approximately parallel to the motherboard 101, rather than standing upright on the motherboard 101. This makes it possible to reduce the height dimension of the housing 110.

[0021] However, due to the above-described arrangement, the expansion boards 106 and 107 are located downstream of the exhaust port 12 in the airflow direction of the fan 3. In this case, if the exhaust direction from the exhaust port 12 were backward (negative direction on the Y axis), the expansion boards 106 and 107 would become an obstacle that blocks the exhaust. Therefore, in this embodiment, the exhaust direction is configured to avoid the expansion boards 106 and 107.

[0022] 3 is a perspective view showing an example of ventilation holes 151 to 157 provided in electronic device 100. This perspective view shows electronic device 100 as seen from the rear side.

[0023] The electronic device 100 includes a fan duct 1, a heat sink 2 and a fan 3 covered by the fan duct 1, a motherboard 101, and a housing 110. The housing 110 houses the motherboard 101 and the fan duct 1, and is provided with ventilation holes 151 to 157 for intake and exhaust.

[0024] The housing 110 includes a front cover 111, a rear cover 112, and an I / O panel 113. The front cover 111 is a part that makes up the front side of the housing 110. The front cover 111 is provided with ventilation holes 151 to 153. The rear cover 112 is a part that makes up the rear side of the housing 110. The rear cover 112 is provided with ventilation holes 154 and 155. The ventilation hole 154 is located at the top of the rear side of the housing 110. The ventilation hole 155 is located at the bottom of the rear side of the housing 110.

[0025] The I / O panel 113 constitutes a part of the rear surface of the housing 110. The I / O panel 113 is provided with ventilation holes 156 and 157. The ventilation holes 156 and 157 are located at the bottom of the rear surface of the housing 110. The ventilation hole 156 is an opening that receives the insertion of a connector into the I / O board (expansion boards 106 and 107).

[0026] Each of the ventilation holes 151 to 157 takes in or exhausts gas (air). Among them, the ventilation holes 154 to 156 provided on the rear side of the housing 110 are mainly responsible for exhausting air.

[0027] In the electronic device 100 of this embodiment, expansion boards 106 and 107 are disposed behind the CPU 102. For this reason, the exhaust port 12 of the fan duct 1 is divided into an exhaust port 121 that opens toward the upper rear and an exhaust port 122 that opens toward the lower rear so that the exhaust air avoids the expansion boards 106 and 107 (see FIG. 1). The exhaust port 12 is divided by a branch wall 13 and a rib 14. The rib 14 is erected on the surface of the branch wall 13 facing the heat sink 2. Furthermore, multiple ribs 14 are provided side by side in the left-right direction at regular intervals.

[0028] The shapes of the branch wall 13 and the ribs 14 will now be described in more detail with reference to Figures 4 and 5. Figure 4 is a plan view illustrating the shape of the fan duct 1. Figure 5 is a vertical cross-sectional side view illustrating the shape of the fan duct 1.

[0029] Branch wall 13 is disposed inside the edge of exhaust port 12, and divides exhaust port 12 into exhaust port 121 and exhaust port 122. Branch wall 13 has a substantially V-shaped cross section in side view, and the bent portion protrudes toward heat sink 2. This divides the flow direction of the gas that has passed through heat sink 2 into two.

[0030] More specifically, the branch wall 13 has two plate-shaped portions 131 and 132. The plate-shaped portions 131 and 132 are continuous with each other at their upstream edges. The plate-shaped portions 131 and 132 are inclined with respect to the airflow direction of the fan 3 so that the distance between them increases toward the downstream side. The first plate-shaped portion 131 guides the gas flow obliquely upward. The second plate-shaped portion 132 guides the gas flow obliquely downward. As a result, the branch wall 13 guides the exhaust air so as to avoid a partial range downstream of itself, thereby branching the exhaust air.

[0031] The angle formed by the two plate-like portions 131, 132 of the branch wall 13 and the airflow direction (negative direction of the Y-axis) of the fan 3 is 45° or more, and the angle formed by the two plate-like portions 131, 132 is a right angle (90°) or an obtuse angle slightly larger than that. The angle setting of this branch wall 13 is determined taking into consideration the lifespan of the mold, ease of manufacturing, etc.

[0032] The ribs 14 are provided to protrude from the surface of the branch wall 13 facing the heat sink 2. The ribs 14 have a mountain-shaped plate shape, and a plurality of ribs 14 are provided side by side in the thickness direction of the ribs 14. The mountain-shaped edges of the ribs 14 in this embodiment are formed linearly.

[0033] The mountain-shaped edges of ribs 14 are inclined with respect to the airflow direction. The angle formed by the mountain-shaped edges of ribs 14 and the airflow direction of fan 3 (negative direction of the Y-axis) is effectively in the range of 20 to 45 degrees, and more preferably about 30 degrees. The angle of the mountain shape at apex 141, which is the most protruding part, is an acute angle.

[0034] The angle setting of the ribs 14 described above is determined based on the results of a simulation of the cooling effect (described later) so that the desired effect can be obtained and the mold can be designed accordingly.

[0035] For example, if the angle formed by the mountain-shaped edge of the rib 14 and the airflow direction of the fan 3 is too large, the desired effect cannot be obtained, and it is desirable that the angle be at least 45° or less to obtain the desired effect.

[0036] Furthermore, if the angle between the mountain-shaped edge of rib 14 and the airflow direction of fan 3 is too small (for example, less than 20°), the tops 141 of rib 14 become too sharp, which is undesirable as it makes filling defects more likely to occur during molding. Furthermore, in this case, if rib 14 is made long (the dimension from top 141 to base is large) in order to ensure a sufficient height dimension at the base, rib 14 will no longer fit within exhaust port 121 in a plan view (as viewed in the negative Z-axis direction), and the structure of the mold will become complicated.

[0037] In order to avoid the above-mentioned inconveniences and obtain the desired effect while being able to mold using a mold with a simple structure that is less likely to cause filling defects, it is desirable that the angle between the mountain-shaped edge of rib 14 and the air blowing direction of fan 3 be between 20° and 45°, and preferably around 30°.

[0038] If the thickness of the base of the rib 14 is 3 mm or less, sink marks are unlikely to occur, and there is no need to apply a mold recess. Also, since there are no walls above or below the rib 14, it can be molded using a normal cavity core. Therefore, the tip of the rib 14 can be made sharp.

[0039] Fig. 6 is a vertical cross-sectional side view illustrating the positional relationship between the fan duct 1 and components (expansion boards 106, 107) near the exhaust ports 12 (121, 122). Fig. 7 is a perspective view showing the arrangement of the exhaust port 121 of the fan duct 1 attached to the electronic device 100. As shown in these figures, the exhaust direction of the exhaust ports 121, 122 is set so that the exhaust avoids the nearby components (expansion boards 106, 107) and passes around them.

[0040] In this configuration, when the electronic device 100 is powered on and operating, the CPU 102, SSD 104, etc. generate heat and their temperatures rise. When the fan 3 operates and blows air, the air inside the fan duct 1 and the housing 110 flows and ventilates, so heat is removed from the CPU 102, etc., preventing them from overheating.

[0041] If the fan duct 1 does not have the branch wall 13 and ribs 14 as in this embodiment, in a simulation of the arrangement shown in Figure 2, the CPU 102 will reach 79.7°C, and the two SSDs 104 will reach 62.6°C and 62.1°C, respectively (this simulation will be referred to as "Simulation A" below).

[0042] In contrast to the above simulation, if the branching wall 13 and ribs 14 as in this embodiment are present, in a similar simulation, the CPU 102 will reach 69.3°C and the two SSDs 104 will reach 54.2°C and 52.5°C, respectively (this simulation will be referred to as "Simulation B" below).

[0043] Incidentally, in a simulation of the fan duct 1 with only the branch wall 13 and no ribs 14, the CPU 102 reached 69.5°C, and the two SSDs 104 reached 54.2°C and 52.5°C, respectively (this simulation will be referred to as "Simulation C" below). In other words, it can be said that the heat dissipation effect is improved when the ribs 14 are provided compared to when they are not provided.

[0044] For the above-mentioned simulations A to C, a fan 3 with specifications that would result in an appropriate intersection (operating point) between the air volume-static pressure characteristic graph of the fan 3 and the ventilation resistance graph of the electronic device 100 was selected, and then the shape and dimensions of the rib 14 and the inclination angle of the plate-like portions 131 and 132 of the branch wall 13 were adjusted. Furthermore, realistic values ​​were used in the adjustments so that the mold for the fan duct 1 would not be impossible to manufacture or would not have a short lifespan.

[0045] According to the simulation, the operating point in simulation C (with only branch wall 13 and no ribs 14) shifted to the side with a larger air volume compared to simulation A (without branch wall 13 or ribs 14). Also, compared to simulation C, the operating point in simulation B (with branch wall 13 and ribs 14) remained almost unchanged, but the maximum air velocity increased. Therefore, according to the simulation, it can be said that by properly providing branch wall 13, at least the air volume increases, and by properly providing ribs 14, at least the maximum air velocity increases. These factors can improve heat dissipation performance.

[0046] In this way, according to the fan duct 1 of the first embodiment, even if there is an obstacle downwind of the fan duct 1, the air can be exhausted while avoiding the obstacle, so that the heat generated inside the electronic device 100 can be properly dissipated.

[0047] As described above, according to this embodiment, it is possible to provide a fan duct 1 and an electronic device 100 equipped with the fan duct 1 that can achieve good heat dissipation performance when there is an obstacle (in this embodiment, expansion boards 106, 107) downwind of the fan 3 that blows air for heat dissipation.

[0048] The above-described embodiment can be modified as needed by partially changing the configuration or functions of each of the above-described devices. Therefore, several modifications of the above-described embodiment will be described below as other embodiments. The following mainly focuses on differences from the above-described embodiment, and detailed descriptions of commonalities with the content already described will be omitted. The modifications described below may be implemented individually or in appropriate combination.

[0049] (Second embodiment) Although the mountain-shaped edges of the ribs 14 in the first embodiment are formed in a straight line, this is not limited to this in practice, and for example, they may be formed in a curved or bent shape so that the angle of inclination with respect to the airflow direction of the fan 3 gradually increases from the top 141 to the base. Such a configuration may reduce the resistance that the top 141 of the rib 14 imparts to the flow of gas, further improving heat dissipation performance.

[0050] (Third embodiment) In the first embodiment, the branch wall 13 and the rib 14 divide the exhaust port 12 into upper and lower halves, but this is not a limitation in practice, and the exhaust port 12 may be divided into left and right halves, for example, depending on the orientation of components that may become obstacles. More specifically, if an expansion board is installed upright in a position downwind of the CPU 102, it is considered preferable to provide the branch wall 13 and the rib 14 to divide the exhaust port 12 into left and right halves.

[0051] (Fourth embodiment) 8 is a plan view showing an example of the shape of the rib 514 provided in the fan duct 1 of the fourth embodiment. The rib 514 of this embodiment is formed so that its thickness gradually decreases from the base to the top 141.

[0052] Compared to the rib 14 of the first embodiment, the rib 514 having such a shape can have a thinner top 141 while maintaining the rigidity of the rib 14 by making the base thicker. The thinner the top 141, the more the loss caused by the flow being blocked by the top 141 can be reduced.

[0053] Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, modifications, and combinations can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0054] 1...Fun duct, 11...Air intake, 12, 121, 122...exhaust port, 13...branch wall, 131...first plate-shaped portion, 132...second plate-shaped portion, 14,514...rib, 141...top, 2...heat sink, 21...base portion, 22...fin, 3...fans, 41-43...frame, 44...helicopter spring, 45...screw, 100...electronic equipment, 101...motherboard, 102...CPU, 103...Memory, 104...SSD, 105...Riser card, 106,107... Expansion board, 110... chassis, 111... front cover, 112... rear cover, 113... I / O panel, 151~157...Ventilation hole. [Prior art documents] [Patent documents]

[0055] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-283171

Claims

1. A fan duct having an intake port and an exhaust port, which covers a heat sink attached to an electronic component and a fan that blows air to the heat sink, The fan is located between the intake port and the exhaust port, the heat sink is located between the fan and the exhaust port and has a base portion in contact with an electronic component and a plurality of fins protruding from the base portion; The protruding direction of the fins is substantially perpendicular to the flow direction of the gas caused by the blown air, a branch wall provided on an edge of the exhaust port and positioned inside the exhaust port, the branch wall having a pair of plate-like portions that are continuous on an upstream side in the gas flow direction and inclined so as to move away from each other toward a downstream side; a plurality of ribs arranged side by side in a thickness direction of the branch wall, the ribs protruding from a surface of the branch wall facing the heat sink, the protruding direction being opposite to the gas flow direction, the most protruding apex of which has a mountain-shaped plate shape with an acute angle; A fan duct equipped with:

2. The angle formed by the two plate-like portions of the branch wall is a right angle or an obtuse angle.

2. The fan duct of claim 1.

3. The rib is formed so that its thickness gradually decreases from the base to the top.

2. The fan duct of claim 1.

4. The mountain-shaped edges of the ribs are curved or bent so that the angle of inclination relative to the airflow direction of the fan gradually increases from the top to the base.

2. The fan duct of claim 1.

5. The angle between the mountain-shaped edge of the rib and the airflow direction of the fan is in the range of approximately 20 to 45 degrees.

2. The fan duct of claim 1.

6. A fan duct according to any one of claims 1 to 5; a heat sink covered by the fan duct; a fan enclosed by the fan duct; a substrate on which electronic components whose heat is dissipated by the heat sink are mounted; a housing that houses the board and the fan duct and has ventilation holes for intake and exhaust; An electronic device comprising:

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