COOLING DEVICE OF ELECTRONIC EQUIPMENT

A first air blowing unit rotates to blow air and includes a first discharge surface for discharging the air. A second air blowing unit rotates to blow the air and includes a second discharge surface for discharging the air. A heat sink includes a plurality of fins. Edges on an upstream side in an air blowing direction of the fins are opposed to the first discharge surface or the second discharge surface. The edges of the fins located on a downstream side of a boundary between the first discharge surface and the second discharge surface are located closer to the first discharge surface and the second discharge surface than the other edges. A duct covers the heat sink, the first air blowing unit, and the second air blowing unit and includes a suction port on the upstream side and an exhaust port on the downstream side.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2022-202904, filed on Dec. 20, 2022, the entire contents of which are incorporated herein by reference.

FIELD

Embodiments described herein relate generally to a cooling device of electronic equipment.

BACKGROUND

Electronic equipment such as a PC (Personal Computer) includes a component heated to high temperature such as a CPU (Central Processing Unit). In general, a heat sink is attached to such a component in order to radiate heat. Air sucked by a fan installed on an upstream side flows to the heat sink and is discharged to a downstream side of the heat sink, whereby the heat radiation is performed.

Recently, there are increasing demands for a reduction in the size of electronic equipment. A reduction in the size of a cooling fan that blows air to a heat sink is demanded. However, if the cooling fan is reduced in size, since a discharge volume of cooling air decreases, cooling performance of the heat sink is undesirably deteriorated.

DETAILED DESCRIPTION

An aspect of embodiments is to provide a cooling device of electronic equipment capable of realizing a reduction in the size of a cooling fan without reducing a discharge volume of cooling air.

A cooling device of electronic equipment according to an embodiment includes a first air blowing unit, a second air blowing unit, a heat sink, and a duct. The first air blowing unit forms a flow of air by rotating to blow the air and includes a first discharge surface for discharging the air. The second air blowing unit forms a flow of the air by rotating to blow the air, includes a second discharge surface for discharging the air, and is installed adjacent to the first air blowing unit. The heat sink has width smaller than a sum of a diameter of the first discharge surface and a diameter of the second discharge surface, a plurality of fins being erected side by side in a thickness direction in a base section of the heat sink to which heat of an electronic component conducts. Edges on an upstream side in an air blowing direction of the fins are opposed to the first discharge surface or the second discharge surface. The edges of the fins located on a downstream side of a boundary between the first discharge surface and the second discharge surface are located closer to the first discharge surface and the second discharge surface than the other edges. The duct covers the heat sink, the first air blowing unit, and the second air blowing unit and includes a suction port on the upstream side and an exhaust port on the downstream side in the air blowing direction by the first air blowing unit and the second air blowing unit.

An embodiment is explained with reference to the drawings.FIG.1is a perspective view illustrating an example of an exterior of a cooling device200in a first embodiment.FIG.2is a perspective view schematically illustrating an example of the structure of electronic equipment100to which the cooling device200is attached. For convenience of explanation, a three-dimensional coordinate system is also illustrated in the drawings. In the three-dimensional coordinate system, a width direction (a left-right direction) of the cooling device200and the electronic equipment100is represented as an X-axis direction, a depth direction (a front-rear direction) thereof is represented as a Y-axis direction, and a height direction (an up-down direction) thereof is represented as a Z-axis direction. Note that a Y-axis positive direction is a direction from the rear side to the front side of the electronic equipment100. The Y-axis positive direction is referred as “front”. A Z-axis positive direction is a down-to-up direction.

First, as illustrated inFIG.1, the cooling device200includes a duct1, a heat sink2, and fans3and4. The duct1has a substantially box-like shape and covers the heat sink2and the fans3and4that blow air to the heat sink2. A suction port11is provided in a position on an upstream side in an air blowing direction of the fans3and4in the duct1. An exhaust port12is provided in a position on a downstream side in the air blowing direction. The duct1discharges, from the exhaust port12, air sucked from the suction port11by the fans3and4. A flowing direction of the air blown by the fans3and4is directed to a Y-axis negative direction (the rear) by the duct1.

In the following explanation, the simple description of the upstream side intends to indicate an upstream side (a windward side) based on a flowing direction of the air in the duct1(the Y-axis negative direction). Similarly, the simple description of the downstream side intends to indicate a downstream side (a downwind side) based on the flowing direction of the air in the duct1.

The heat sink2is generally formed of a metal material having high thermal conductivity such as aluminum or copper and is attached to an electronic component (a heat source) that generates heat. The heat source is, for example, a CPU (Central Processing Unit). Heat generated by the CPU conducts to the heat sink2. Heat of the heat sink2is dispersed to the air around the heat sink2. Consequently, malfunction and the like due to overheat of the CPU are prevented.

The heat sink2includes a base section21and a plurality of fins22. The base section21receives conduction of heat emitted by the electronic component. The plurality of fins22are provided to be erected side by side in the thickness direction on the base section21. The plurality of fins22are adjacent to one another at predetermined intervals from one another. The base section21is in contact with the CPU and receives the conduction of the heat of the CPU. The fins22emit (radiate), to the air, the heat conducting from the base section21that is continuous to the fins22. The air flowing in the duct1passes among the fins22of the heat sink2, whereby the heat radiation is accelerated.

The heat sink2is fixed, by helical springs84and screws85, on frames81and82formed in layers at a predetermined interval. A motherboard101(seeFIG.2) is sandwiched between the frame81and the frame82.

The fan3is an example of the first air blowing unit in the present disclosure. The fan4is an example of the second air blowing unit in the present disclosure. The fan3includes a first discharge surface32for discharging the air sucked from the outside toward the heat sink2. The fan4includes a second discharge surface42for discharging the air sucked from the outside toward the heat sink2.

The fan3and the fan4in this embodiment have the same size, pass the center position in the width direction of the heat sink2along an X axis and are disposed symmetrically with respect to a surface parallel to the fins22(a surface parallel to a YZ plane) at an included angle of 90 degrees or more.

The fans3and4are axial fans and continuously blow the air by driving to rotate, for example, with conduction motors, propellers including one or more blades around rotating shafts. The air blown by the fans3and4forms a flow of the air among the fins22. The air blown by the fans3and4carries the heat emitted by the fins22and the base section21to the downstream side and accelerates the heat radiation. In this way, the fans3and4cool the heat sink2.

In this embodiment, the suction port11, the fan3or the fan4, the heat sink2, the exhaust port12are disposed in this order from the upstream side toward the downstream side in the air flowing direction in the duct1. The air sucked from the suction port11and blown by the fans3and4mainly flows around the fins22of the heat sink2to take away heat of the fins22and is discharged from the exhaust port12.

The duct1causes the air blow by the fan3to efficiently act on the heat radiation of the heat sink2and improves a heat radiation effect. Specifically, the duct1surrounds the heat sink2and delimits a range in which the air blown by the fan3for cooling the heat sink2flows. Gas in the duct1is replaced with gas sucked from the suction port11by rotation of the fan3and is pushed out from the discharge port12. Consequently, gas around the heat sink2is quickly replaced.

In order to sufficiently exert the effects of the cooling device200explained above, a component (an obstacle) that hinders exhaust is desirably absent on the downwind side of the exhaust port12. However, an obstacle is sometimes disposed on the downstream side of the exhaust port12depending on the size of the electronic equipment100including the cooling device200, disposition of an object built in the cooling device200, and the like.

As illustrated inFIG.2, the electronic equipment100includes a motherboard101, a CPU102, memories103, SSDs (Solid State Drives)104, a riser card105, an I/O board106, and a housing110. The housing110houses the units described above (the motherboard101, the CPU102, the memories103, the SSDs104, the riser card105, and the I/O board106).

The motherboard101is an example of a substrate on which the electronic component (in this embodiment, the CPU102), the heat of which is radiated by the heat sink2, is mounted. Since the memories103and the SSDs104also generate heat according to operation, the memories103and the SSDs104can be heat sources. The heat generated by the heat sources is also emitted by the flow of the gas in the housing110formed by the air blow of the fans3and4.

The I/O board106is connected to the motherboard101via an insertion port (a slot) included in the riser card105. Since the I/O board106is disposed in parallel to the mother board101by being connected to the insertion port included in the riser card105, it is possible to suppress a height dimension of the housing110.

However, if the I/O board106is located further on the downstream side than the exhaust port12because of the disposition explained above, the I/O board106hinders the exhaust. This embodiment is configured such that the exhaust from the duct1avoids the I/O board106.

FIG.3is a perspective view illustrating an example of vent holes161to167provided in the electronic equipment100. The perspective view is a view of the electronic equipment100viewed from the rear side.

The duct1is housed on the inside of the housing110of the electronic equipment100. In the housing110, the vent holes161,162, and163for taking in the air sucked into the inside of the duct1and the vent holes164,165, and167for discharging the air passed through the duct1are provided.

The vent holes161,162, and163are provided in a front cover111configuring the front surface of the housing110. The vent holes164are provided in a rear cover112configuring the rear surface of the housing110. The vent holes165and167are provided in an I/O panel113configuring a part of the rear surface of the housing110. The I/O panel113includes connection terminals for connecting various kinds of peripheral equipment to the electronic equipment100.

In the electronic equipment100in this embodiment, the I/O board106is disposed behind the CPU102. Therefore, the exhaust port12of the duct1is divided into, such that the exhaust avoids the I/O board106, an upper exhaust port121opened upward and a lower exhaust port122opened downward (seeFIG.1). Specifically, the exhaust port12is divided into the upper exhaust port121and the lower exhaust port122by a branch wall13.

FIG.4is a perspective view illustrating an example of a shape of the duct1. The duct1has a shape formed by opening a side on which the fan3and the fan4are attached and the side of the exhaust port12.

The duct1includes a top plate10and sidewalls15to18. The top plate10configures a Z-axis direction upper part of the duct1and is opposed to the distal end portions of the fins22. The sidewalls17and18are opposed to both side portions of the heat sink2. The sidewalls15and16connect the sidewalls17and18and side portions of the fans3and4and surround a space between the fans3and4and the heat sink2.

With the duct1explained above, the air blown by the fans3and4reaches the heat sink2without leaking from the duct1. The sidewalls15and16are examples of a first wall section in the present disclosure.

The branch wall13is provided on the downstream side (the Y-axis negative side) of the duct1. The branch wall13includes an upper wall section131and a lower wall section132. The upper wall section131and the lower wall section132are connected on a side extending along the X axis on the upstream side in the air blowing direction. The upper wall section131and the lower wall section132are inclined with respect to the air blowing direction such that the distance between the upper wall section131and the lower wall section132is larger further on the downstream side in the air blowing direction.

The air passed among the fins22of the heat sink2reaches the branch wall13. The upper wall section131guides, obliquely upward, a part of the air passed among the fins22of the heat sink2and discharges the part of the air from the upper exhaust port121. The lower wall section132guides, obliquely downward, the remaining air passed among the fins22of the heat sink2and discharges the remaining air from the lower exhaust port122. In this way, the branch wall13guides the exhaust air to avoid a part of a range on the downstream side of the branch wall13and causes the exhaust air to branch. Therefore, even if peripheral equipment such as the I/O board106(seeFIG.3) is disposed in a position on the downstream side of the branch wall13, cooling performance of the heat sink2is not hindered.

FIGS.5,6, and7are schematic plan views of the cooling device200for explaining a relation between the directions of the discharge surfaces32and42of the fans3and4and the shape of the edges of the fins22.FIGS.5to7illustrate examples different from one another.

First, the fans3and4common to the examples are explained. The fan3includes a plurality of blades that rotate around the rotating shaft. The fan3discharges, from the first discharge surface32, the air sucked from the suction port11. The first discharge surface32is a circular region. Similarly, the fan4includes a plurality of blades that rotate around the rotating shaft. The fan4discharges, from the second discharge surface42, the air sucked from the suction port11. The second discharge surface42is a circular region.

The fan3and the fan4have the same size. The size of the fan3and the fan4is set such that the sum of the diameter of the first discharge surface32and the diameter of the second discharge surface42is larger than the width of the heat sink2.

The first discharge surface32from which the fan3discharges the air and the second discharge surface42from which the fan4discharges the air are symmetrically disposed across a fin221in the center in the width direction of the heat sink2(the X-axis direction) on the upstream side of the heat sink2.

Further, a housing of the fan3and a housing of the fan4are adjacent to each other without a gap. Therefore, the housing of the fan3, the housing of the fan4, the sidewalls15and16, and the top plate10(seeFIG.4) surround a space on the upstream side of the heat sink2. Therefore, the air blown by the fan3and the fan4reaches the heat sink2without leaking to the outside of the duct1.

The sidewalls15and16of the duct1are provided to gradually reduce the interval between the sidewalls15and16in a part from the suction port11to the heat sink2. Therefore, the air blown by the fan3is directed to the center in the width direction along the sidewall15and the air blown by the fan4is directed to the center in the width direction along the sidewall16.

Subsequently, the example illustrated inFIG.5is explained. In the heat sink2in this example, edges on a side opposed to the first discharge surface32or the second discharge surface42(edges of the fins22on the upstream side in the air blowing direction) of the fins22are located along a ridge-shaped imaginary line projecting in the center in an arranging direction of the fins22(the X-axis direction). In other words, the edges on the side opposed to the first discharge surface32or the second discharge surface42of the fins22are located to draw a ridge shape projecting most in the fin221in the center.

An edge of the fin221in the center is located on the downstream side of a boundary between the first discharge surface32and the second discharge surface42(a position where the housing of the fan3and the housing of the fan4are in contact). The edge of the fin221in the center is located closest to the fans3and4and intervals between the edges of the other fins22and the fans3and4are wider than an interval between the fin221in the center and the fans3and4. The edges of the fins22in other than the center farther away from the center are located farther from the first discharge surface32or the second discharge surface42.

In this example, the fans3and4are disposed such that an angle formed by the first discharge surface32and the fin221in the center and an angle formed by the second discharge surface42and the fin221in the center are equal and an included angle between the first discharge surface32and the second discharge surface42is 90° or more. That is, the fans3and4are disposed such that an angle formed by the fin221in the center and the first discharge surface32or the second discharge surface42is 45° or more.

If the angles are set smaller, that is, if the included angle between the fan3and the fan4is set smaller than 90°, since an angle formed by a traveling direction of the air discharged by the fans3and4and the fins22increases and resistance in the air changing the air flowing direction along the fins22increases, the flow of the air tends to be disturbed. Accordingly, the included angle between the fan3and the fan4is desirably 90° or more.

The fin221in the center functions as a wall extending in the height direction (the Z-axis direction) between the position between the fan3and the fan4and the center position in the width direction of the heat sink2(the X-axis direction). The air blown by the fan3and the air blown by the fan4are separated by the fin221in the center. An inconvenience of flows of the air blown by the fan3and the air blown by the fan4interfering with each other is avoided. With such structure, the air blown by the fan3and the air blown by the fan4are guided to the heat sink2without being mixed.

The edges opposed to the first discharge surface32or the second discharge surface42of the fins22in this example respectively include end faces substantially parallel to the thickness direction (the X-axis direction). The air blowing direction of the fans3and4in this example is not parallel to a Y axis but is inclined with respect to the Y axis. Therefore, the end faces of the edges of the fins22explained above are inclined with respect to an air discharging direction from the first discharge surface32or the second discharge surface42and are not orthogonal to the air discharging direction. Accordingly, the air blown by the fan3and the air blown by the fan4do not collide with the end faces of the fins22to be blocked.

If the edges of the fins22did not project in the ridge shape, since the air blown by the fan3and the air blown by the fan4collide with each other in the center in the width direction, the flow would be disturbed. In this case, flow velocity is likely to inconveniently decrease.

However, in this example, since the edges of the fins22are projected in the ridge shape, the air blown by the fan3and the air blown by the fan4are prevented from being mixed and, at the same time, the edges of the fins22do not have orthogonal surfaces opposed to the first discharge surface32or the second discharge surface42. Therefore, it is possible to improve stability of the flow of the air in the duct1.

Subsequently, the example illustrated inFIG.6is explained. In the explanation of this example, explanation of portions common to the example illustrated inFIG.5is omitted and different portions are explained.

In this example, the included angle between the first discharge surface32and the second discharge surface42is 180°. That is, the angle formed by the fin221in the center and the first discharge surface32or the second discharge surface42is 90°.

In a heat sink201in this example, the edges opposed to the first discharge surface32or the second discharge surface42of the fins22respectively include the end faces inclined with respect to the thickness direction (the X-axis direction). The air blowing direction of the fans3and4in this example is parallel to the Y-axis direction. Therefore, the end faces of the edges of the fins22explained above are inclined with respect to the air discharging direction from the first discharge surface32or the second discharge surface42and is not orthogonal to the air discharging direction. Accordingly, the air blown by the fan3and the air blown by the fan4do not collide with the end faces of the fins22to be blocked.

The example explained above does not deny that the fan3and the fan4are installed in a state in which the included angle exceeds 180º. That is, the included angle between the fan3and the fan4may be set larger than 180º (up to, for example, approximately 200°).

Subsequently, the example illustrated inFIG.7is explained. In the explanation of this example, explanation of portions common to the example illustrated inFIG.6is omitted and different portions are explained.

In a heat sink202in this example, the edges on the side opposed to the first discharge surface32and the second discharge surface42of the fins22are located along a W-shaped imaginary line projecting in the center and both the ends in the arranging direction of the fins22(the X-axis direction). In other words, the edges on the side opposed to the first discharge surface32and the second discharge surface42of the fins22are located to draw a W shape formed by projecting the fins22in the center and at both the ends.

With the heat sink202in this example, the sum of the surface areas of the fins22can be set larger than that of the heat sink201in the example illustrated inFIG.6. Therefore, it is possible to obtain the heat sink202having higher heat radiation power.

In the examples explained above, the fans3and4are disposed symmetrically with respect to the heat sink2. However, in implementation, the disposition of the fans3and4is not limited to this. The fans3and4may not be symmetrically disposed with respect to the heat sink2.

Since the fans3and4suck, from the suction port11, the air to be blown against the heat sink2, an air current occurs in a position facing the suction port11. Heat generated by components located near the suction port11is carried and taken away by the air current. That is, a flow of the air formed by the fans3and4is considered to facilitate heat radiation of not only the heat source that is in contact with the base section21of the heat sink2but also the components near the suction port11.

Accordingly, the fans3and4may be disposed with intention to facilitate heat radiation of components around the fans3and4.

As explained above, the cooling device200in the embodiment includes the fan (the first air blowing unit)3, the fan (the second air blowing unit)4, the heat sink2, and the duct1. The fan3forms a flow of air by rotating to blow the air and includes the first discharge surface32for discharging the air. The fan4forms a flow of the air by rotating to blow the air, includes the second discharge surface42for discharging the air, and is installed adjacent to the fan3. The duct1covers the heat sink2, the fan3, and the fan4and includes the suction port11on the upstream side in the air blowing direction by the fans3and4and the exhaust port12on the downstream side in the air blowing direction. The heat sink2has width smaller than the sum of the diameter of the first discharge surface32and the diameter of the second discharge surface42, the plurality of fins22being erected side by side in the thickness direction in the base section21of the heat sink2to which the heat of the electronic component such as the CPU102conducts. Edges on the upstream side in the air blowing direction of the fins22are opposed to the first discharge surface32or the second discharge surface42. The edge of the fin221in the center located on the downstream side of the boundary between the first discharge surface32and the second discharge surface42is located closer to the first discharge surface32and the second discharge surface42than the edges of the other fins22.

With the structure explained above, the cooling device200can perform the air blow to the heat sink2with the plurality of fans3and4and can direct, with the fin221in the center further projecting than the other fins22, the flows of the air blown from the fan3and the air blown from the fan4toward the heat sink2without causing the flows to interfere with each other. Consequently, in cooling the heat sink2with the two fans3and4in which the sum of the diameters of the discharge surfaces32and42is larger than the width of the heat sink2, it is possible to suppress a loss of energy and efficiently cool the heat sink2. Accordingly, even if a large-diameter fan cannot be used because of, for example, the height of the housing110of the electronic equipment100, by adopting a plurality of fans3and4that supply an air volume equivalent to that of the large-diameter fan in cooperation with one another, it is possible to realize a reduction in the size of (reduce the height direction dimension of) the cooling fans without reducing a discharge volume of cooling wind.

The fans3and4in the embodiment explained above have the same size. However, in implementation, the sizes of the plurality of fans3and4do not always need to be the same. Outputs (wind velocities and air volumes to be obtained) of the fans3and4may be different.

While several embodiments are explained above, these embodiments are presented as examples and are not intended to limit the scope of invention. These new embodiments can be implemented in other various forms. Various omissions, substitutions, and changes can be made in a range not departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and the gist of the invention and included in the inventions described in the claims and a scope of equivalents of the inventions.