The present application claims priority under 35 U.S.C. ยง 119 to Japanese Patent Application No. 2020-168096, filed on Oct. 2, 2020, the entire contents of which are hereby incorporated herein by reference.
The present disclosure relates to a cooling device.
Conventionally, a cooling device is used for cooling a heating element. The cooling device often has a plurality of fins. When a cooling medium such as air flows between the fins adjacent to each other in the plurality of fins, heat from the heating element often moves to the cooling medium.
In recent years, for example, cooling of a CPU, a GPU, or the like provided in a server device has become important, and it is desired to improve cooling performance when a cooling device is used for such cooling.
An example embodiment of a cooling device of the present disclosure includes at least one fin laminated body which extends in a first direction and includes fins laminated in a second direction perpendicular to the first direction, and a heat conductor which extends in the second direction and is inside the fin laminated body. A second-direction interval between adjacent ones of the fins on one side of the fin laminated body in the first direction is greater than another second-direction interval between adjacent ones of the fins on another side of the fin laminated body in the first direction.
The above and other elements, features, steps, characteristics and advantages of the present disclosure will become more apparent from the following detailed description of the example embodiments with reference to the attached drawings.
Example embodiments of the present disclosure will be described below with reference to the drawings.
In the drawings, a first direction is defined as an X direction, one side in the first direction is defined as X1, and the other side in the first direction is defined as X2. As will be described later, the first direction is a direction in which a cooling medium A flows, one side in the first direction corresponds to an upstream side, and the other side in the first direction corresponds to a downstream side.
A direction perpendicular to the first direction is defined as a second direction (Y direction), one side in the second direction is defined as Y1, and the other side in the second direction is defined as Y2. Further, a direction perpendicular to the first direction and the second direction is defined as a third direction (Z direction), one side in the third direction is defined as Z1, and the other side in the third direction is defined as Z2.
The cooling device 1 is a device which cools a plurality of heating elements 5A and 5B (
The heating elements 5A and 5B are preferably, for example, a CPU or a GPU provided in the server device. In this case, the cooling device 1 is mounted on the server device. The heating elements 5A and 5B may be, for example, power transistors of an inverter included in a traction motor for driving wheels of a vehicle. The power transistor is, for example, an insulated gate bipolar transistor (IGBT). In this case, the cooling device 1 is mounted on the traction motor. The number of heating elements may be a plurality other than two, or may be one.
The cooling device 1 includes a fin laminated body 200, a plurality of heat conductors 3, and a base member 4.
The fin laminated body 200 includes a plurality of fins 2. The plurality of fins 2 include a plurality of first fins 21 and a plurality of second fins 22. The first fin 21 and the second fin 22 have different shapes, and are plate-like members extending in the first direction and having the second direction as a thickness direction. The first fin 21 and the second fin 22 are formed of, for example, an aluminum alloy.
The first fins 21 and the second fins 22 are alternately disposed in the second direction. The fin laminated body 200 is configured by laminating the first fin 21 and the second fin 22 in the second direction. That is, the fin laminated body 200 includes the plurality of fins 2 extending in the first direction and disposed to be laminated in the second direction.
The first fin 21 includes wide portions 211 and 212 and a narrow portion 213 (
The second fin 22 includes a narrow portion 221 and a wide portion 222. The wide portion 222 is wider in the third direction than the narrow portion 221. The wide portion 222 is disposed on the other side of the narrow portion 221 in the first direction. Accordingly, the second fin 22 has a T shape as viewed in the second direction.
The wide portion 222 of the second fin 22 overlaps the wide portion 212 of the first fin 21 as viewed in the second direction. The narrow portion 221 of the second fin 22 overlaps a part of the narrow portion 213 of the first fin 21 on the other side in the first direction as viewed in the second direction.
As illustrated in
As illustrated in
As illustrated in
Here, the first fin 21 may be configured to be divided in the first direction by the first region R1 and the second region R2. In this case, each of the divided portions has a T shape. However, it is necessary to position the divided fins in the second direction at the time of assembling the fins. On the other hand, in the case of the first fin 21 as illustrated in
In a case where the divided fins are used as described above, the fin laminated body is formed on each of one side in the first direction and the other side in the first direction. That is, it is sufficient if the cooling device 1 has at least one fin laminated body.
The shapes of the first fin 21 and the second fin 22 are not limited to the above, and may be, for example, rectangular when viewed in the second direction.
Each of the plurality of heat conductors 3 is configured as a heat pipe extending in the second direction. Each of the plurality of heat conductors 3 penetrates the fin laminated body 200 from the other side in the second direction to the one side in the second direction. That is, the heat conductor 3 extends in the second direction and is disposed inside the fin laminated body 200. For example, the end portion of the heat conductor 3 on one side in the second direction may not protrude from the fin 2 disposed closest to one side in the second direction.
The plurality of fins 2 are connected to the heat conductor 3 by, for example, caulking, heat welding, bonding, or the like. The detailed configuration of the heat conductor 3 will be described later.
In the arrangement example of the heat conductor 3 illustrated in
As illustrated in
The base member 4 is a metal member formed of, for example, an aluminum alloy, and has a plate shape with the second direction as a thickness direction. The base member 4 is disposed on the other side of the plurality of heat conductors 3 in the second direction. The end portion of each of the plurality of heat conductors 3 on the other side in the second direction is connected to the base member 4. In the example of
As illustrated in
In a case where three heating elements are cooled, for example, one heating element may be disposed in the first region R1, another heating element may be disposed from the first region R1 to the second region R2, and the remaining heating element may be disposed in the second region R2. Alternatively, a single heating element disposed from the first region R1 to the second region R2 may be cooled.
As illustrated in
The heat generated by the heating elements 5A and 5B is transferred to the fins 2 via the base member 4 and the heat conductor 3, and is dissipated to the cooling medium A flowing between the fins 2. Accordingly, the heating elements 5A and 5B can be cooled.
Here, as illustrated in
In a case where the cooling medium A flows in between the fins 2 from one side of the fin laminated body 200 in the first direction, the cooling medium A flowing between the fins 2 (first fins 21) on the upstream side has a relatively low temperature and is sufficiently cooled on the upstream side. Thus, even when the second-direction interval P1 of the fins 2 on the upstream side is widened to reduce the heat-dissipation area of the fins 2, there is no influence on cooling of the heating element. Even when the cooling performance is improved by increasing the flow rate of the cooling medium A flowing into the cooling device 1, the pressure loss can be suppressed and the decrease in the flow rate of the cooling medium A flowing between the fins 2 on the upstream side can be suppressed by widening the second-direction interval P1 between the fins 2 on the upstream side. Accordingly, the cooling performance on the upstream side can be improved. Further, noise can be reduced by suppressing the pressure loss.
The inflow cooling medium A collides with an upstream end portion 21T (
In a case where the flow of the cooling medium A is a laminar flow, heat exchange is actively performed in a boundary layer between the fin 2 and the cooling medium A, but the heat exchange is less likely to be performed when the cooling medium A moves away from the boundary layer. On the other hand, when the flow of the cooling medium A is a turbulent flow, the pressure and the flow rate change irregularly, so that the boundary layer between the fin 2 and the cooling medium A is actively exchanged, and the heat exchange is more actively performed. Since the heat exchange in the fluid is performed in a wider range than the laminar flow due to the turbulence of the flow, the substantial heat transfer coefficient is increased. Therefore, the cooling capacity is improved at the place where the turbulent flow is generated.
Therefore, in a case where the fan device 15 having a large air volume is used, the cooling performance of the cooling device 1 can be improved.
For example, in the fin laminated body 200, the first fins 21 may be laminated in the second direction at the second-direction interval P2 in a partial region in the second direction. In this case, in the partial region, the interval between the fins 2 is the same on the upstream side and the downstream side. That is, it is sufficient if the second-direction interval P1 between adjacent fins 2 on one side in the first direction in at least one of the plurality of fins 2 is wider than the second-direction interval P2 between adjacent fins 2 on the other side in the first direction in at least one of the plurality of fins 2.
In the example of
As illustrated in
As illustrated in
At this time, when the cooling device 1 is installed such that the second direction is a vertical direction (gravity direction), and the other side in the second direction is the ground side, the working medium easily returns to the heating elements 5A and 5B side by gravity, and the cooling performance of the heating elements 5A and 5B can be improved.
The installation direction of the cooling device 1 is not limited to the above, and for example, the other side in the second direction may be set as the wall surface side of the installation target equipment.
Various example embodiments described below can be applied to the configuration of the fin 2 described above.
As illustrated in
As illustrated in
As illustrated in
The opposing surfaces 201A and 201B face a direction in which the cooling medium A flows. That is, at least one of the plurality of fins 2 has the opposing surfaces 201A and 201B facing the first direction. Further, the opposing surfaces 201A and 201B are disposed between both end portions of the fin 2 in the first direction. Accordingly, the turbulent flow of the cooling medium A is easily generated in the vicinity of the opposing surfaces 201A and 201B.
When the first recess 201 is provided, opposing surfaces such as the opposing surfaces 201A and 201B can be provided on both guide surface sides.
As illustrated in
Since the opposing surfaces 202A and 202B face the first direction, the turbulent flow of the cooling medium A is easily generated in the vicinity of the opposing surfaces 202A and 202B. Further, when the first recess 201 and the second recess 202 are provided, the cooling medium A smoothly flows along the outer surface of the second recess 202, which protrudes toward the first guide surface 2S1, on one side in the first direction and the inner surface of the first recess 201, which is recessed toward the second guide surface 2S2, on the other side in the first direction, and the cooling medium A smoothly flows along the inner surface of the second recess 202, which is recessed toward the first guide surface 2S1, on one side in the first direction and the outer surface of the first recess 201, which protrudes toward the second guide surface 2S2, on the other side in the first direction.
As illustrated in
As illustrated in
As illustrated in
Accordingly, in the fin 2, a opposing surface Sa is formed on one side in the second direction, and a opposing surface Sb is formed on the other side in the second direction. Since the opposing surfaces Sa and Sb face the first direction, the turbulent flow of the cooling medium A is easily generated in the vicinity of the opposing surfaces Sa and Sb.
Accordingly, a part of the through-hole 2H becomes a opposing surface 2H1 facing the first direction. That is, the opposing surface 2H1 is provided in the through-hole 2H.
Therefore, the turbulent flow of the cooling medium A is easily generated in the vicinity of the opposing surface 2H1. The opposing surface 2H1 can be formed by a simple method of forming the through-hole 2H in the fin 2. Further, it is also easy to form a large number of through-holes 2H in the fin 2.
The example embodiment of the present disclosure has been described above. The scope of the present disclosure is not limited to the above example embodiment. The present disclosure can be implemented by making various modifications to the abovementioned example embodiment without departing from the gist of the disclosure. In addition, the matters described in the above example embodiments can be arbitrarily combined together, as appropriate, as long as there is no inconsistency.
For example, the cooling medium A in which the turbulent flow is generated in the second region R2 (
The cooling medium A is not limited to air, and may be water, for example. In this case, the cooling device 1 is a water-cooled device.
The present disclosure can be used, for example, for cooling various heating elements.
Features of the above-described preferred example embodiments and the modifications thereof may be combined appropriately as long as no conflict arises.
While example embodiments of the present disclosure have been described above, it is to be understood that variations and modifications will be apparent to those skilled in the art without departing from the scope and spirit of the present disclosure. The scope of the present disclosure, therefore, is to be determined solely by the following claims.
Number | Date | Country | Kind |
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2020-168096 | Oct 2020 | JP | national |