---

Register or Login To Download This Patent As A PDF

United States Patent Application	20030168208
Kind Code	A1
Sato, Kaoru	September 11, 2003

---

---

---

Foreign Application Data

---

Date	Code	Application Number
Mar 11, 2002	JP	2002-64898

---

Claims

---

What is claimed is:

1. A cooling apparatus comprising: a heat transfer plate having a heat-receiving surface; a heat sink having a plurality of fins erected on said heat transfer plate on a surface opposed to said heat-receiving surface; a blower for said heat sink; and baffling members each for controlling an air path between said fins of said heat sink.

2. The cooling apparatus of claim 1, wherein each of said baffling members makes a clearance between said fins smaller than other portions.

3. The cooling apparatus of claim 1, wherein one of said baffling member and corresponding one of said fins are in contact with each other.

4. The cooling apparatus of claim 1, wherein each of said baffling members is shaped like one of a plate, column, and comb.

5. A cooling apparatus comprising: a heat transfer plate having a heat-receiving surface; a heat sink having a plurality of fins erected on said heat transfer plate on a surface opposed to said heat-receiving surface; a blower for said heat sink; and air-guiding members each inserted between said fins of said heat sink for guiding an air path toward a central portion of said heat sink.

6. The cooling apparatus of claim 5, wherein one of said air-guiding members and corresponding one of said fins are in contact with each other.

7. A cooling apparatus comprising: a heat transfer plate having a heat-receiving surface; a heat sink having a plurality of fins erected on said heat transfer plate on a surface opposed to said heat-receiving surface; a blower for said heat sink; and air-guiding members each inserted between said fins of said heat sink for guiding an air path toward a central portion of said heat transfer plate.

8. A cooling apparatus comprising: a heat transfer plate opposed to a heat-generating body in contact therewith and protruding oppositely to a heat-receiving surface thereof; a heat sink having a plurality of fins erected on said heat transfer plate on a surface opposed to said heat-receiving surface; a fan as a blower for said heat sink; and baffle plates each disposed between said fins of said heat sink.

9. The cooling apparatus of claim 8, wherein each of said baffle plates disposed between said fins of said heat sink is perpendicular to a fan-attaching surface.

10. The cooling apparatus of claim 8, wherein each of said baffle plates disposed between said fins of said heat sink is at an angle with respect to a fan-attaching surface.

11. The cooling apparatus of any one of claims 9 and 10, wherein each of said baffle plates disposed between said fins of said heat sink is shaped like a comb.

12. The cooling apparatus of any one of claims 9 and 10, wherein each of said baffle plates disposed between said fins of said heat sink is formed by cutting and raising a portion of each fin.

13. The cooling apparatus of any one of claims 9 and 10, wherein said baffle plates are disposed between said fins of said heat sink so that at least two baffle plates corresponds to one fin.

14. A cooling apparatus comprising: a heat transfer plate opposed to a heat-generating body in contact therewith and protruding oppositely to a heat-receiving surface thereof; a heat sink having a plurality of fins erected on said heat transfer plate on a surface opposed to said heat-receiving surface; a blower for said heat sink; and baffle plates disposed on a side wall of said heat sink through which air is blown.

15. The cooling apparatus of claim 11 further comprising: a duct for guiding exhausted fluid to an outside of the cooling apparatus; wherein said blower is disposed one of between said duct and a housing wall and in the middle of said duct.

16. The cooling apparatus of claim 12 further comprising: a duct for guiding exhausted fluid to an outside of the cooling apparatus; wherein said blower is disposed one of between said duct and a housing wall and in the middle of said duct.

17. A cooling apparatus comprising: a heat transfer plate having a heat-receiving surface; a heat sink having:. a plurality of fins erected on said heat transfer plate on a surface opposed to said heat-receiving surface; and baffling members each for controlling an air path between said fins of said heat sink; a fan for blowing air from said heat sink; and a duct as an air path for said fan.

---

Description

---

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a heat sink used to cool a heat-generating component, e.g. a micro processing unit (herein after abbreviated as an MPU), for use in a personal computer, and also relates to a cooling apparatus for cooling a heat-generating body by combining the heat sink with a blowing measure, e.g. a fan.

[0003] 2. Background Art

[0004] In recent electronic equipment, with higher integration of electronic components, e.g. semiconductors, and higher frequencies of operating clocks, the heat values thereof are increasing. This makes a large problem of how to maintain the temperature of bonded portion of each electronic component within the range of the operating temperature thereof for normal operation. Especially, the degree of integration and the frequencies of MPUs are prominently increasing. Additionally, in order to ensure stable performance and operating life thereof, heat dissipation is becoming an important problem to be addressed.

[0005] Generally used to cool a heat-generating body, e.g. an MPU, is a cooling apparatus made of a heat sink for increasing a heat dissipation area and efficiently exchanging heat with a coolant, e.g. air, and a motorized fan for forcedly supplying the coolant, e.g. air, to this heat sink. In general, the heat sink is essentially consisting of a material exhibiting high heat conductivity, such as aluminum and copper, and manufactured by a method, such as ejector molding (or pultrusion molding), cold forging, die casting, and lamination of thin plates.

[0006] Conventional examples are described with reference to FIGS. 6 and 7.

[0007] The drawings of FIG. 6 are front views and side views of a conventional cooling apparatus showing a structure having different air blowing directions of a fan thereof. The drawings of FIG. 7 show an example of a structure of another conventional cooling apparatus in which baffle plates for controlling airflow are incorporated in the cooling apparatus of FIG. 6.

[0008] When such a cooling apparatus is used, a heat sink is mounted on heat-generating body 3 in contact therewith, as shown in FIGS. 6A to 6D. As for the actual cooling principle of the cooling apparatus, heat generated in the heat-generating body is transferred to plate-like fins 1 via heat transfer plate 2 made of a material having high heat conductivity, e.g. aluminum, as shown in FIG. 6A. The heat on the surfaces of plate-like fins 1 is transferred to the air supplied from cooling fan 4 and thereby dissipated into the air and cooled.

[0009] As for the heat dissipation performance of a cooling apparatus, it is generally considered that when the air quantity around a fin is equal, increasing the surface area by increasing the number of fins can simply improve the heat dissipation capability. However, in fact, the heat dissipation capability decreases in some cases, when it is considered based on the heat dissipation quantity per unit area. As the number of heat dissipating fins increases, the clearance between the fins capable of receiving airflow becomes smaller. This increases the resistance of inflow air and reduces the total quantity of inflow air. As a result, despite of the increased surface area, the heat dissipation capability decreases. In other words, simply increasing the number of heat dissipating fins is not effective.

[0010] In order to improve the performance of a cooling apparatus, it is most desirable to maintain the apparatus so that heat is uniformly distributed throughout the heat sink and all the fins formed for heat dissipation can dissipate heat.

[0011] For many of the conventional cooling apparatuses as shown in FIG. 6A, because the heat-generating body itself is extremely smaller than the entire heat sink and thus the contact area between them is small, heat from the heat-generating body tends to be intensively transferred only to fins directly above the heat-generating body. For this reason, in such a structure, simply blowing air from the cooling fan to the heat sink cannot necessarily provide high cooling performance. Additionally, because of the structure of electronic equipment, the cooling fan is sometimes used in a blow-in mode, as shown in FIG. 6C. In this structure, because air streams 7a flowing in the heat sink through the side faces thereof are likely to flow through the side faces nearer to the fan side of the heat sink, only little air flows into the dissipating fins in the vicinity of a region directly above the heat-generating body, which is considered to have the highest temperature. Therefore, a region of stale air, i.e. a region in which almost no heat dissipation action works (hereinafter referred to as a "dead region", is locally generated in some cases. This dead region is a factor of further deteriorating the cooling performance.

[0012] As described above, as for important factors in determining the performance of a cooling apparatus, it is most desirable to maintain the temperature throughout the heat sink as uniform as possible and secure sufficient heat dissipation area and air quantity. These conditions are ideal and, in fact, the actual structure makes difficult to maintain these conditions in many cases. Therefore, another method is considered. From the viewpoint of heat transfer characteristics, a structure in which air quantity as much as possible can be secured in a high-temperature region can provide higher performance.

[0013] In consideration of this viewpoint, an improvement has been devised in order to improve the heat dissipation performance in a structure as shown in FIG. 7A. For example, proposed in Japanese Patent Application Unexamined Publication No. H09-153573 is a method of preventing generation of dead region 10 directly above the heat-generating body of FIG. 6C in the following manner. As shown in FIG. 7A, baffle plates 9 attached to the side faces of the heat sink allows formation of air streams 7c that flow into the heat sink through the side faces thereof. Air streams 7c push down mainstreams 7a of the airflow toward the heat-generating body side of the heat sink and guide much of the airflow to the vicinity of the highest temperature region.

[0014] However, because further progress in speed-up of electronic components, e.g. semiconductors, tends to cause the electronic components to generate more heat, it is becoming difficult that a cooling apparatus of a conventional structure sufficiently cools the electronic components. Especially, electronic components involving more heat generation, e.g. MPUs, have problems: the electronic components cannot achieve sufficient performance, or thermal runaway thereof causes abnormality in electronic equipment incorporating the electronic components.

[0015] Especially when a structure in a conventional blow-in mode as shown in FIG. 6C is unavoidably selected, a method of using baffle plates 9 as shown in FIG. 7A are employed to prevent generation of the dead region of airflow. This structure is preferable in that the air quantity as much as possible can be secured in the highest temperature region. However, even with the structure of FIG. 7A, dead regions 10 still exist behind baffle plates 9. Although the performance of the apparatus of FIG. 7A is more improved than that of FIG. 6C, the surface area of the heat sink still has useless dead regions that do not contribute to heat dissipation. These dead regions pose a problem: sufficient heat dissipation performance cannot be obtained.

[0016] Further, in order to meet the recent demand of further higher performance, many of cooling apparatuses are structured so that the heat sink is wider than the fan. For this reason, generation of these dead regions is unavoidable. Similarly, as shown in FIG. 7C, when the heat sink is wider than the fan even with a cooling fan in a blow-out mode, generation of dead regions 10 is unavoidable. Thus, it is difficult to make the entire heat sink achieve its full heat dissipation performance.

SUMMARY OF THE INVENTION

[0017] The present invention provides a cooling apparatus having:

[0018] a heat transfer plate having a heat-receiving surface;

[0019] a heat sink having a plurality of fins erected on the heat transfer plate on a surface opposed to the heat-receiving surface;

[0020] a blower for the heat sink; and

[0021] baffling members each for controlling an air path between the fins of the heat sink.

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] FIGS. 1A, 1B, 1C, and 1D are front views and side views of a cooling apparatus in accordance with a first exemplary embodiment of the present invention.

[0023] FIGS. 2A, 2B, 2C, and 2D are front views and side views of a cooling apparatus in accordance with a second exemplary embodiment of the present invention.

[0024] FIGS. 3A, 3B, and 3C are a plan view, a front view, and a side view, respectively, of a cooling apparatus in accordance with a third exemplary embodiment of the present invention.

[0025] FIGS. 4A, 4B, and 4C are a plan view, a front view, and a side view, respectively, of another cooling apparatus in accordance with the third exemplary embodiment of the present invention.

[0026] FIGS. 5A, 5B, 5C, and 5D are front views and side views of a cooling apparatus in accordance with a fourth exemplary embodiment of the present invention.

[0027] FIGS. 6A, 6B, 6C, and 6D are front views and side views of a conventional cooling apparatus.

[0028] FIGS. 7A, 7B, 7C, and 7D are front views and side views of another conventional cooling apparatus.

[0029] FIGS. 8A, 8B, 8C, 8D and 8E are front views, side views, and a perspective view of an essential part of a cooling apparatus in accordance with a fifth exemplary embodiment of the present invention.

[0030] FIGS. 9A,; 9B, 9C, 9D and 9E are front views, side views, and a perspective view of an essential part of another cooling apparatus in accordance with the fifth exemplary embodiment of the present invention.

[0031] FIGS. 10A, 10B, 10C and 10D are a plan view, a front view, a side view, and a perspective view of an essential part, respectively, of another cooling apparatus in accordance with the fifth exemplary embodiment of the present invention.

[0032] FIGS. 11A, 11B, 11C and 11D are a plan view, a front view, a side view, and a perspective view of an essential part, respectively, of sill another cooling apparatus in accordance with the fifth exemplary embodiment of the present invention.

[0033] FIGS. 12A, 12B, 12C, 12D and 12E are front views, side views, and an enlarged detail view of an essential part of yet another cooling apparatus in accordance with the fifth exemplary embodiment of the present invention.

[0034] FIGS. 13A, 13B, 13C, and 13D are a plan view, a front view, a side view, and an enlarged detail view of an essential part of, respectively, of a cooling apparatus in accordance with a sixth exemplary embodiment of the present invention.

[0035] FIGS. 14A, 14B, 14C and 14D are front views and side views of another cooling apparatus in accordance with the sixth exemplary embodiment of the present invention.

[0036] FIGS. 15A and 15B are front views and side views of cooling systems in accordance with a seventh exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0037] Exemplary embodiments of the present invention are demonstrated hereafter with reference to the accompanying drawings.

[0038] First Exemplary Embodiment

[0039] FIG. 1A shows a cooling apparatus in accordance with the first exemplary embodiment. FIGS. 1A and 1B are a front view and a side view, respectively, of the cooling apparatus of the first exemplary embodiment when a cooling fan thereof is used in a blow-in mode. FIGS. 1C and 1D are a front view and a side view, respectively, of the cooling apparatus when the cooling fan is used in a blow-out mode.

[0040] With reference to FIG. 1A, plate-like fins 1 are formed on heat transfer plate 2. Heat transfer plate 2 includes fins 1. Heat-generating body 3 is placed under heat transfer plate 2. In this case, a heat sink is made of plate-like fins 1. Heat-generating body 3 includes heat-generating electronic components including semiconductors or transistors, such as an IC, LSI, and MPU.

[0041] Generally, for heat dissipating equipment opposed to a small heat-generating body in contact therewith, when heat flows into isotropic material through a heat-receiving surface, the heat tends to diffuse with a semispherical temperature distribution. Therefore, an ideal shape of a heat sink is structured to have a semispherical heat transfer portion and a large number of heat dissipating fins radially formed around a heat-generating source at the center of the heat transfer portion. It is effective to reduce the temperature distribution throughout the heat sink, in improving heat dissipation characteristics. However, such a structure poses various problems other than performance: the shape and size are not suitable for actual application, or manufacturing cost is extremely expensive.

[0042] In order to reduce cost and ensure performance of a cooling apparatus in recent downsized electronic equipment, a heat sink made of ejected aluminum is used in many cases. Recently, heat dissipation characteristics have been improved by reducing the clearance between the fins, increasing the number of fins, and thus increasing the surface area of the heat sink. However, there is a technical problem: the extrusion technique for reducing the clearance between the fins is extremely difficult. Additionally, too small clearance between the fins restricts the inflow air quantity and deteriorates the performance, against the expectation. Thus, this method is not necessarily a wise way. Therefore, as described above, if air can be guided toward a high-temperature region as much as possible, higher performance can be expected, from the viewpoint of heat transfer characteristics.

[0043] As described in FIG. 7A, there is an example of improving the performance by attaching baffle plates 9 to the side faces of the heat sink. The baffle plates control airflow and guide much of the airflow toward the heat-generating body side. However, even in this case, generation of dead regions that do not contribute to heat dissipation cannot be prevented. Thus, there is still a problem that not all the surface area of the heat sink can effectively be utilized.

[0044] Therefore, in order to address this problem, in a cooling apparatus of the present invention, a heat sink and comb-like baffle plates combine. The present invention can realize a cooling apparatus that can make the heat sink reach its maximum performance and has excellent heat dissipation characteristics.

[0045] For a cooling apparatus of the first exemplary embodiment shown in FIGS. 1A through 1D, a heat sink is structured so that plate-like fins 1 erect on a surface opposed to a surface of heat transfer plate 2 that is in contact with a heat-generating body, and a cooling fan is mounted on plate-like fins 1. Additionally, as shown in FIGS. 1A through 1D, in each clearance between plate-like fins 1 in the vicinity of both side faces of the heat sink, comb-like baffle plate 6 is disposed from the cooling fan attaching surface on the top face of the heat sink to the heat transfer plate side.

[0046] FIGS. 1A and 1B show an example of a cooling apparatus in which a cooling fan thereof is used in a blow-in mode. Disposing comb-like baffle plate 6 in each clearance between plate-like fins 1 in this manner allows formation of air streams 7c that flow into the heat sink through the side faces thereof. These air streams 7c push down mainstreams 7a of the air toward the heat-generating body side in the heat sink, which has the highest temperature. Thus, the heat dissipation characteristics can be improved, like the cases shown in FIGS. 7A through 7D. Further, formation of air streams 7b each flowing into the heat sink through each clearance between plate-like fin 1 and comb-like baffle plate 6 can prevent generation of dead regions of air, which are generated in the cases shown in FIGS. 7A and 7B. This structure increases the effective surface area of the heat sink, thereby achieving higher heat dissipation characteristics. As for the effect of these comb-like baffle plates 6, because the air flowing into each clearance between comb-like baffle plate 6 and plate-like fin 1 forms turbulent flow, this turbulent flow can change the dead regions as shown in FIGS. 7A through 7D to regions having high heat dissipation characteristics (high heat conductivity).

[0047] Now, a brief description is provided of the relation between heat dissipation and heat conductivity. Generally, when heat is dissipated into the air from a metal surface, the higher the heat conductivity, the larger the heat dissipation quantity. Further, the thinner the boundary layer of the fluid, the higher the heat conductivity. It is known that this boundary layer is thinner in turbulent flow than in laminar flow. Therefore, generation of turbulent flow is one of the methods of improving heat dissipation characteristics (hereinafter referred to as the "effect of turbulent flow").

[0048] FIGS. 1C and 1D show an example of the cooling apparatus in which the cooling fan is used in a blow-out mode. Also in the blow-out mode, disposing comb-like baffle plate 6 in each clearance between plate-like fins 1 allows mainstreams 8a of the airflow in the blow-out mode to be pushed down toward the heat-generating body side in the heat sink, which has the highest temperature. Further, in a similar manner, air streams 8b each flowing into the heat sink through each clearance between plate-like fin 1 and comb-like baffle plate 6 are formed. This can prevent generation of dead regions of air, and increase the effective surface area of the heat sink, thereby achieving higher heat dissipation characteristics.

[0049] Top cover 5 provided on the top face of the heat sink as shown in the drawings is necessary only when the heat sink is larger than the fan, which is necessitated by higher performance of the cooling apparatus. When the heat sink and the fan are of the same size, top cover 5 is not necessary. However, even in this case, dead regions 10 as shown in FIGS. 6A through 6D or FIGS. 7A through 7D do not disappear completely. Thus, even when the heat sink and the heat sink are of the same size, high performance cannot always be obtained.

[0050] Second Exemplary Embodiment

[0051] FIGS. 2A through 2D show a cooling device in accordance with the second exemplary embodiment. FIGS. 2A and 2B are a front view and a side view, respectively, of the cooling apparatus of the second exemplary embodiment when a cooling fan thereof is used in a blow-in mode. FIGS. 2C and 2D are a front view and a side view, respectively, of the cooling apparatus when the cooling fan is used in a blow-out mode. The basic structure of the apparatus shown in FIGS. 2A through 2D is substantially similar to that of the first exemplary embodiment described with reference to FIGS. 1A through 1D. In this embodiment, descriptions are mainly provided of what is different from the cases shown in FIGS. 1A through 1D. What is largely different from the cases shown in FIGS. 1A through 1D is that comb-like baffle plates 6 disposed between the fins in the vicinity of the side faces of the heat sink are at an angle with respect to the fan attaching surface. This structure allows formation of external air streams 7c along the surfaces of comb-like baffle plates 6, in the case shown in FIGS. 2A and 2B. These air streams 7c can more actively guide mainstreams 7a of the airflow toward the vicinity of a region having the highest temperature directly above the heat-generating body than the cases shown in FIGS. 1A through 1D. Thus, higher heat dissipation characteristics can be achieved.

[0052] Similarly, also in the case shown in FIGS. 2C and 2D, blow-in air streams 8c are generated along the surfaces of comb-like baffle plates 6. These air streams 8c can actively guide the mainstreams 8a of the airflow toward the vicinity of a region having the highest temperature directly above the heat-generating body. Thus, high heat dissipation characteristics can be achieved.

[0053] Third Exemplary Embodiment

[0054] FIGS. 3A through 3C show a cooling apparatus in accordance with the third exemplary embodiment. A cooling fan thereof in a blow-in mode is disposed on a side face of a heat sink. FIGS. 3A, 3B, and 3C are a plan view, a front view, and a side view, respectively, of the cooling apparatus. Similar to the case shown in FIGS. 2A and 2B, disposing comb-like baffle plate 6 in each of the clearances between plate-like fins 1 allows formation of air streams 7c that flow into the heat sink through the side face thereof. Air streams 7c push down mainstreams 7a of the airflow toward the heat-generating body side of the heat sink, which has the highest temperature, thereby improving the heat dissipation characteristics. Additionally formed are air streams 7b that flow into the heat sink through the clearances between plate-like fins 1 and comb-like baffle plates 6. This structure is similar to that of the cases shown in FIGS. 1A through 1D. Therefore, it is possible to prevent generation of dead regions of air, increase the effective surface area of the heat sink, and achieve high heat dissipation characteristics using the effect of turbulent flow.

[0055] FIGS. 4A through 4C show another example of the cooling apparatus in accordance with the third exemplary embodiment. In this example, the cooling fan in a blow-out mode is disposed on a side face of the heat sink. FIGS. 4A, 4B, and 4C are a plan view, a front view, and a side view, respectively, of the cooling apparatus. Also in this case, similar to the case shown in FIGS. 2C and 2D, blowing air streams 8c are generated along the surfaces of comb-like baffle plates 6. Air streams 8c can actively guide mainstreams 8a of the airflow toward the vicinity of a region having the highest temperature in the heat sink directly above the heat-generating body. Thereby, high heat dissipation characteristics can be achieved.

[0056] Fourth Exemplary Embodiment

[0057] FIG. 5 shows front views and side views of a cooling apparatus in accordance with the fourth exemplary embodiment. FIGS. 5A and 5B are a front view and a side view, respectively, of the cooling apparatus, when a cooling fan thereof is used in a blow-in mode. FIGS. 5C and 5D are a front view and a side view, respectively, of the cooling apparatus when the cooling fan is used in a blow-out mode. What is different from the cases shown in FIGS. 1A through 1D of the first exemplary embodiment is that comb-like baffle plates 6 are not disposed between plate-like fins 1, but disposed on the side faces of the heat sink. From the viewpoint of heat dissipation characteristics, basically, effects substantially similar to those of the first exemplary embodiment can be achieved.

[0058] Fifth Exemplary Embodiment

[0059] FIGS. 8A through 12E show cooling apparatuses in accordance with the fifth exemplary embodiment. As for the structure of each drawing, FIGS. 8A through 8E correspond to a first example, FIGS. 9A through 9E correspond to a second example, FIGS. 10A through 10D and FIGS. 11A through 11D correspond to a third example, and FIGS. 12A through 12E correspond to a fourth example. The respective examples can achieve substantially similar effects. In the first through fourth embodiments, comb-like baffle plates are used to control the airflow. In contrast, in the fifth embodiment, these baffle plates are formed by cutting and raising or bending a portion of each plate-like fin 1 as raised baffle plate 11 (hereinafter referred to as a "baffle plate"). This is only one difference. Basically, this structure can achieve effects substantially similar to those of the first through fourth embodiments, from the viewpoint of heat dissipation characteristics.

[0060] In other words, baffle plate 11 existing between the fins as shown in FIGS. 1A and 1B need not be disposed at the center of the clearance between fins necessarily. As shown in FIGS. 8A through 8E or FIGS. 9A through 9E, the baffle plate can sufficiently control the airflow even from one side if there is a sufficient baffling width effective in the airflow control. Therefore, baffle plate 11 can be disposed between the fins in contact with either of the fins on both sides. All the baffle plates 11 need not be cut and raised in one direction necessarily, in the cooling apparatus shown in FIGS. 8A through 8E. However, when a manufacturing process is considered, forming in one direction is desirable. In a blow-in mode in which air flows into the heat sink through the right and left sides thereof, the slot made by cutting and raising baffle plate 11 should be formed so that the slot is disposed behind baffle plate 11 and baffle plate 11 is against the direction in which air flows into. When the positions of the baffle plate and the slot are reversed, the air impinging upon baffle plate 11 goes into the slot made by cutting and raising baffle plate 11 and passes through the fins themselves, which deteriorates the effect of baffle plates 11.

[0061] Sixth Exemplary Embodiment

[0062] FIGS. 13A through 13D and FIGS. 14A through 14D show cooling apparatuses in accordance with the sixth exemplary embodiment.

[0063] FIGS. 13A through 13D and FIGS. 14A through 14D show a few examples of the position of the baffle plates. FIGS. 13A through 13D show an example in which the respective baffle plates between corresponding plate-like fins 1 are not aligned. Even with such a configuration, airflow control can be performed without any problem. Thus, cooling performance substantially similar to that of the cases shown in FIGS. 8A through 8E can be expected. FIGS. 14A through 14D show examples in which a plurality of baffle plates are disposed on one fin. Also in these cases, a plurality of baffle plates are disposed perpendicular to or at an angle with respect to the heat-receiving surface. Each of the cases has a configuration in which the effects substantially similar to those of the cases shown in FIGS. 8A through 8E or FIGS. 9A through 9E can be expected.

[0064] Additionally, disposing at least two baffle plates per fin of the heat sink easily makes the airflow between the baffle plates form turbulent flow. Thus, heat dissipation characteristics can be improved.

[0065] Seventh Exemplary Embodiment

[0066] FIGS. 15A and 15B show cooling systems in accordance with the seventh exemplary embodiment. Shown in each of 15A and 15B is an example in which the above-mentioned cooling apparatus and a duct combine. Each drawing shows how a fan, i.e. a blower, and duct 14 are disposed between housing wall 13 and a heat sink, using the fan in a blow-in mode.

[0067] In FIG. 15A, the fan is disposed on the housing wall. In FIG. 15B, the fan is disposed in the middle of the duct. With each of these configurations, the air in the housing is sucked into the heat sink in the blow-in mode, the hot air dissipated from the heat sink can be directly exhausted to the outside of the housing via the duct. This can prevent temperature rise in the housing caused by the heat exhausted from the heat sink. As a result, the temperature of the air flowing into the heat sink can be kept low and extremely high cooling performance can be achieved.

[0068] In the present invention, disposing baffle plates having a pitch equal to that of the fins of the heat sink on a side face or the top face of the heat sink allows the mainstreams of the air flowing into the heat sink through the side face or the top face thereof to be guided toward the heat-generating body side of the heat sink. This can improve heat dissipating characteristics.

[0069] In the present invention, a duct for guiding exhausted heat fluid to the outside is added to a structure comprising: a heat transfer plate opposed to a heat-generating body in contact therewith and protruding oppositely to a heat-receiving surface thereof; a heat sink having a plurality of fins erecting on the heat transfer plate oppositely to the heat-receiving surface, and baffle plates; and a fan, i.e. a blower for the heat sink. This configuration can further improve heat dissipating characteristics.

[0070] As described hereinabove, in each of the cooling apparatuses of the exemplary embodiments, disposing comb-like baffle plates or raised baffle plates between the fins of the heat sink or on a side wall of the heat sink through which air is blown can prevent generation of dead regions of air and allows mainstreams of the cooling air to be guided toward the vicinity of a region directly above the heat-generating body. This structure can realize a cooling apparatus having extremely high heat dissipation performance. Additionally, configuring a new cooling system in which one of the cooling apparatuses of these embodiments and a duct combine can make the cooling apparatus achieve maximum performance it originally has.

[0071] The comb-like baffle plate or raised baffle plate shown in these embodiments is shaped like a plate. However, because the original purpose of the baffle plate is guiding air toward the vicinity of a region in the heat sink directly above the heat-generating body, the baffle plate need not be shaped like a plate necessarily. The baffle plate can be shaped like a rod, column, or prism.

[0072] For the cooling apparatuses of the exemplary embodiments, disposing comb-like baffle plates or raised baffle plates between the fins of the heat sink or on a side wall of the heat sink through which air is blown allows mainstreams of the cooling air to be guided toward the vicinity of a region directly above the heat-generating body. This structure can make the heat sink achieve the heat dissipation characteristics it originally has, thereby providing an electronic component cooling apparatus having excellent cooling performance.

* * * * *