JP2013165120A - Cooling component, cooling device, and cooling method for heating element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling component using a heat sink having spindle-like fins of which cross section is spindle-shaped (or like a rugby ball), and a cooling device.SOLUTION: A spindle-like fin 2 has one end and the other end in its longitudinal direction, the width of its central part in the longitudinal direction is larger than that of its other parts, and the shape of the cross section of the fin 2 parallel to the longitudinal direction is substantially spindle-shaped. A cooling device includes: a cooling component in which the plurality of spindle-like fins 2 are erected so as to form a single row in a direction perpendicular to the longitudinal direction on the surface of a heating element 3; and blasting means for sending air such that air flows from any one end in the longitudinal direction of the spindle-like fins 2 to the other end, along clearances formed by the surface of the heating element 3 and the adjacent wall surfaces of the erected spindle-like fins 2.

Description

  The present invention relates to a technical field for cooling a heat generating portion of an electronic device or the like.

  In recent years, information communication in electronic devices including information processing devices such as servers and workstations that exchange information with user terminals due to the progress of information processing in companies and the use of the Internet in society. Many are used.

  Recently, the amount of business data to be processed and the amount of data such as voice and moving images has increased rapidly, and these information processing devices etc. The processing load on various semiconductors and devices increases, and these semiconductors and devices generate heat.

  Therefore, it is important for such an information processing apparatus or the like to properly cool the heat generated by the various semiconductors and devices incorporated therein in order to operate them stably.

  In addition, since the information processing apparatus or the like is a basic system that processes various types of company data or is a so-called infrastructure of society that always provides various services, electronic devices including related information processing apparatuses are Reliability through stable operation is even more important.

  In addition, in a server room that houses an information processing apparatus, for example, as described above, it can operate stably even in an installation environment where the air conditioning temperature is slightly higher due to social demands for power saving. Therefore, it is necessary to effectively cool the inside of each information processing apparatus and the like accommodated therein.

  Specifically, a central processing unit (hereinafter referred to as CPU) included in an information processing apparatus such as a server or a workstation, a graphic (drawing) function, a storage function, a data input / output function, a network communication function, etc. A large scale integrated circuit (hereinafter referred to as an LSI) that controls various peripheral functions of a CPU or an LSI (hereinafter referred to as an LSI collectively) that controls the functions described above when operating. ) Etc. and various peripheral function devices are operated while cooling so as not to exceed the guaranteed operating temperature.

  Although there are technologies such as air cooling and water cooling in the method of cooling the inside of such an information processing apparatus, heat is transferred into the air due to heat generation from LSI etc. in the apparatus, cost, housing structure and maintainability. In many cases, forced air cooling that cools by using a heat sink to dissipate and a fan using a motor for exchanging the heat of the heat by blowing is used.

  In forced cooling using a heat sink and a fan as described above, for example, by increasing the surface area of the heat sink itself, increasing the air volume of the fan, increasing the wind speed, or improving the thermal conductivity of the heat sink material Has improved cooling efficiency.

  However, in case of electronic equipment including information processing devices whose mounting volume is limited due to standardization of the case size or specific application, an increase in the area of the heat sink for cooling efficiency improvement, The increase in fan diameter is physically limited.

  Moreover, even if the area of the heat sink is simply increased, not all portions necessarily contribute to heat dissipation due to heat transfer loss due to heat conduction.

  Moreover, even if the fan diameter can be increased or the fan rotation speed can be increased, the housing size becomes large, and power consumption and noise increase.

  In addition to the application of heat sink materials with good thermal conductivity and the addition of fans that individually cool LSIs, for example, in addition to fans that cool the entire device such as an information processing device, it is generally expensive. End up.

  Therefore, for example, in an information processing apparatus such as a server or a workstation, while the entire apparatus is cooled by air blowing, an increase in heat generated by the operation of the LSI or the like using the air blowing is increased without increasing the air volume of the air blowing source. There is a case where efficient cooling is expected so that the temperature is within a stable operating range including a remarkable device.

  Here, the technology disclosed in Patent Document 1 is a heat sink that makes contact with a heat generating part of a small processing unit (Micro Processing Unit; hereinafter referred to as MPU) included in a notebook personal computer (hereinafter referred to as PC). Disclosed is a cooling device for a heat generating element that forcibly cools heat transmitted from a heat generating part by blowing air by mounting a fan on the surface opposite to the above.

  According to the technique described in Patent Document 1, a plurality of fins each having a cross-sectional shape of a bird wing (hereinafter referred to as wing fins) are provided on the upper surface of the heat sink, and the shape of the wing fins is followed. Air is blown from a fan built in the heat sink so that air can flow.

  And by reducing air resistance using winged fins, it is possible to suppress a decrease in air volume, so that heat dissipation efficiency can be increased and turbulence can be suppressed by smoothing the flow of air. Therefore, it is disclosed that noise generated in the wing fin portion can be reduced.

JP 2000-332177 A

  However, according to the technique described in Patent Document 1 described above, even if the airflow can be prevented from being lowered by making the fin shape into a wing shape, the air flow rate is improved and the heat dissipation efficiency is further improved. It may not be possible.

  The reason is that the length of the wing fins extending along the direction of air flow is short and divided, and the individual surface area is small, so that it is difficult to transfer heat to the air flowing through the wing fins. This is because the airflow is often collided with the wing-like fins arranged in series in the downstream direction in which the air flows because the airflow is arranged at equal intervals vertically and horizontally, and improvement in the airflow velocity cannot be expected.

  Further, according to the technique described in Patent Document 1 described above, a plurality of wing-shaped fins are arranged uniformly in the vertical and horizontal directions at equal intervals, but this may not always be efficient.

  The reason for this is that the heat distribution on the opposite surface (hereinafter referred to as the heat dissipation surface) of the heat sink due to conduction heat from the contact location (hereinafter referred to as the heat transfer surface) of the heat sink where the LSI as the heat source is in surface contact. Is not uniform due to heat transfer loss, the temperature at the center of the heat dissipation surface of the heat dissipation surface corresponding to the heat transfer location of the heat transfer surface is the highest, and the temperature decreases as it goes to the peripheral portion around that location. For this reason, the wing-like fins distributed in the vertical and horizontal directions from the central portion to the peripheral portion have poor heat dissipation efficiency.

  Furthermore, even though it is possible to cool the relevant part such as an LSI by using a heat sink in which a plurality of wing fins and a fan that blows air are integrated, the LSI, a sub board on which the LSI is mounted, a memory, It is not always possible to simultaneously cool an entire device having other heat sources such as storage.

  Further, in addition to a fan as shown in Patent Document 1 mounted on a heat sink that individually cools a CPU or the like, when an additional fan that cools the entire apparatus is provided, the apparatus size increases or the apparatus cost increases. May go up.

  The main object of the present invention is to provide a cooling member, a cooling device, and the like using a heat sink having a spindle-shaped fin having a spindle (or rugby ball-like) cross section in order to solve the above-described problems. It is in.

  In order to solve the above problems, the cooling device according to the present invention has one end and the other end in the longitudinal direction, the width of the central portion in the longitudinal direction is longer than the width in other portions, and is parallel to the longitudinal direction. A plurality of spindle-shaped fins, each of which has a substantially spindle-shaped cross-section, standing on the surface of the heating element so as to form a single row in a direction perpendicular to the longitudinal direction; Air passes along the gap including the surface formed by the surface and the adjacent wall surface of the plurality of spindle-shaped fins standing from one end in the longitudinal direction of the spindle-shaped fin toward the other end. Air blowing means for blowing air to flow.

  ADVANTAGE OF THE INVENTION According to this invention, when air passes the ventilation flow path between the several spindle shaped fins of a heat sink, a cooling efficiency can be improved locally.

It is a side view which shows the outline of the structure of the cooling member in the 1st Embodiment of this invention. It is AA sectional drawing of the cooling member shown in FIG. It is a perspective view which shows the structure of the heat sink in the 2nd Embodiment of this invention. It is a top view which shows the structure of the heat sink in the 2nd Embodiment of this invention. It is a top view which shows typically the flow of the air which passes the heat sink in the 2nd Embodiment of this invention. It is a top view which shows the cooling device using a general heat sink and an air cooling fan. It is a perspective view which shows the application example of the cooling device in the 2nd Embodiment of this invention. It is a top view which shows typically the flow of the air on the component mounting board | substrate surface of the information processing apparatus by the cooling device in the 2nd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description of the present invention, three-dimensional coordinate symbols are used in the drawings for convenience of description of member shapes and devices.

<First Embodiment>
The cooling member of the 1st Embodiment of this invention is demonstrated with reference to FIG. 1 and FIG.

  FIG. 1 is a side view schematically showing the structure of a cooling member in the first embodiment of the present invention.

  The cooling member 1 shown in FIG. 1 is composed of a plurality of spindle-shaped fins 2 and has a structure in which the heating element 3 and the spindle-shaped fins 2 shown below the spindle-shaped fins 2 are physically and thermally coupled toward the drawing. Have taken.

  2 is a cross-sectional view taken along line AA of the cooling member 1 shown in FIG. That is, as shown in FIG. 1, the spindle-shaped fin 2 shown in FIG. 2 has an AA cross section parallel to the surface of the heating element 3 standing on the spindle-shaped fin 2, and the spindle-shaped fin 2 is cut into a ring. It is the figure seen from the upper surface.

  As shown in FIG. 2, a plate-shaped plate having one end and the other end in the longitudinal direction, and having a substantially spindle shape with a width in the direction perpendicular to the longitudinal direction at the center of the longitudinal direction, which is longer than other portions. It is a member (fin).

  The cooling member 1 has a structure in which a plurality of spindle-shaped fins 2 are erected in parallel so as to form a single row. Further, the cooling member 1 generates heat generated by the heating element 3 shown below the spindle-shaped fin 2 (in the figure, − (minus) Z-axis direction, hereinafter the same) as shown in FIG. While conducting to the plurality of spindle-shaped fins 2, the heat is dissipated into the space of the environment where the cooling member 1 is installed.

  Then, either the longitudinal direction of the spindle-shaped fin 2 shown in FIG. 1, that is, either the front side or the other side of the cooling member 1 shown in FIG. 1 (± (plus or minus) Y shown in the figure) Dissipation of the heat is promoted by blowing air from the axial direction (hereinafter the same) using air blowing means (not shown).

  In other words, the air is heated by the conduction heat from the heating element 3 generated in the air gap between the surface of the heating element 3 standing on the spindle-shaped fin 2 and the plurality of spindle-shaped fins 2 as shown in FIG. The air can be expelled in the ± Y-axis directions shown in the figure. At that time, the space sandwiched between the plurality of spindle-shaped fins 2 shown in FIG. 2, that is, the shape of the ventilation channel, is because the adjacent wall surfaces of the spindle-shaped fins 2 face each other in a convex curve shape. The ventilation channel has a shape in which the cross-sectional area of both end portions in the longitudinal direction is large and the cross-sectional area of the central portion is small.

  As a result, the air from the ± Y-axis direction shown in FIG. 2 is blown by a blowing means (not shown), and the inlet and outlet of the ventilation channel are wide and the central portion passes through the narrowest space, so that the inlet From the center to the center, the flow velocity of the blown air accelerates.

  This promotes the dissipation of heat conducted from the heating element 3 to the spindle fin 2.

  In addition, in the ventilation passage between the plurality of spindle-shaped fins 2 shown in FIG. 1, the lower side toward the paper surface is the heat generating surface of the heating element 3, and the upper side toward the paper surface is the open end portion of the spindle-shaped fin 2. The left and right are substantially U-shaped structures composed of adjacent wall surfaces of the spindle-shaped fins, and the length from the surface of the heating element 3 on which the spindle-shaped fins 2 stand up to the open end of the spindle-shaped fins 2 is Unless it is extremely short, the heated air in the ventilation channel between the plurality of spindle-shaped fins 2 by the air blown from the ± Y-axis direction shown in the figure is opposite to the direction in which the blown air flows. It can be driven out in any of the ± Y-axis directions shown in the figure.

  That is, according to the cooling member according to the present embodiment, when the air passes through the ventilation channel between the plurality of spindle-shaped fins, the cooling speed is locally improved by improving the wind speed. Can do.

  The structure and number of spindle-shaped fins 2 shown in FIGS. 1 and 2 are examples for explaining the structure of the cooling member 1 of the present embodiment, and the present invention is limited to such structure and number. is not.

<Second Embodiment>
Next, a second embodiment based on the first embodiment will be described.

  A heat sink, which is a cooling device according to a second embodiment of the present invention, will be described with reference to FIGS. In addition, in the following description, while it demonstrates in detail centering on the characteristic part which concerns on this embodiment, the same code | symbol is attached | subjected to the part same as the structure of 1st Embodiment, and it overlaps. Is omitted.

  FIG. 3 is a perspective view showing the structure of the heat sink in the second embodiment of the present invention. FIG. 4 is a top view showing the structure of the heat sink in the second embodiment of the present invention.

  The heat sink 5 shown in FIG. 3 is a base plate 4 that is a rectangular flat plate serving as a base having a predetermined thermal conductivity and vertical, horizontal, and thickness that are in contact with a heating element such as an LSI and a heat transfer surface (not shown). A plurality of spindle-shaped fins 2 are integrally provided on the base plate 4 at a predetermined interval perpendicular to the heat dissipating surface opposite to the heat transfer surface of the base plate 4.

  As shown in FIG. 4, the spindle-shaped fin 2 is a plate-like member whose cross-sectional shape cut by a plane parallel to the heat radiating surface of the base plate 4 is substantially spindle-shaped when viewed from above.

  The spindle fin 2 and the base plate 4 have the same or equivalent material and thermal conductivity.

  The structure and the number of spindle-shaped fins 2 shown in FIGS. 3 and 4 are examples for explaining the structure of the heat sink 5 of the present embodiment, and the present invention is not limited to such structure and number. Absent.

  Here, the heat transfer surface (not shown) where the above-described base plate 4 is in contact with the heating element constitutes an LSI (not shown) and a heat generating portion that generates heat when the LSI or the like operates. A silicon die of a semiconductor chip, or a case made of metal or the like that covers the die so as to protect it from physical damage and conducts heat of the die, which is larger than the die area (so-called CPU or LSI heat spreader). The same applies to the surface below).

  At that time, the contact is made with a predetermined pressure through silicon grease or the like having a good thermal conductivity, so that they are thermally coupled with a low thermal resistance.

  The material of the base plate 4 and the spindle-shaped fin 2 standing on the heat radiating surface of the base plate 4 may be a metallic material from the viewpoint of thermal conductivity, workability, cost, and the like.

  The type is aluminum, copper, or an alloy containing these as main components.

However, the material is not limited to the above-described materials, and any material that is not illustrated in FIGS. 3 and 4 and that can maintain the cooling target within the range of the guaranteed operating temperature by a fan that blows air, which will be described later. For example, other existing materials such as ceramic and stone may be used.
For convenience of explanation, a fan is described as a typical blower, but a blower other than a fan may be used as long as it is a blower that can blow (the same applies to the following description).

  For the method of integrating the base plate 4 and the spindle-shaped fin 2, for example, if it is a metallic material, an existing method of integrally forming such as casting (so-called die casting) or machining is used. The heat sink 5 can be selected according to conditions such as the size, cost, and manufacturing quantity of the target heat sink 5.

  For example, if many pieces are manufactured, a casting method using a mold that can reduce the cost can be adopted.

  Further, when the members of the base plate 4 and the spindle-shaped fin 2 are separate and combined, the joining method is a shape slightly smaller than the cross-sectional shape of the spindle-shaped fin 2 (not shown) on the heat radiation surface of the base plate 4. Then, after digging a groove having a predetermined depth by the number of spindle-shaped fins 2 and press-fitting the spindle-shaped fins 2 there, or using the above-described fitting technique, the base plate 4 and The base portion with the spindle-shaped fin 2 can be welded, for example, if it is a metallic material. For example, an existing brazing technique for joining the base plate 4 and the spindle-shaped fin 2 by melting an alloy material such as aluminum solder. Technology may be used.

  In addition, from the viewpoint of thermal conductivity, it is desirable to integrally mold with the same material having good thermal conductivity as described above. However, when the members are joined, the spindle-shaped fins are joined from the members of the base plate 4 by joining. It is only necessary to select a construction method in which the decrease in the thermal conductivity to the member 2 is not significant, and the cooling target can maintain the operation guaranteed temperature range by cooling by blowing air from a fan described later.

  Further, the size of the base plate 4, the size including the thickness of the central portion of the spindle-shaped fin 2, the dimensions of the interval between the adjacent spindle-shaped fins 2, the thermal conductivity of the base plate 4 and the spindle-shaped fin 2, and the ventilation of the cooling fan The amount of air to be blown, the wind speed, the number of spindle-shaped fins 2 and the smoothness of the surface of the spindle-shaped fins 2 are those described below in the environment where the apparatus is installed. What is necessary is just to determine so that the cooling object may be maintained in the range of operation guarantee temperature by cooling with the ventilation from.

  Further, the length from the heat radiating surface of the base plate 4 to the open end of the spindle-shaped fin 2 (+ (plus) Z-axis direction shown in FIG. It is sufficient if the length of the spindle-shaped fin 2 in the longitudinal direction is such that it is difficult for air to flow out from the open end of the fin 2, and if the length cannot be secured, the spindle described in the application example described later. By applying a structure that closes the upper part of the fin 2, it is possible to suppress the outflow of air from the open end.

  Further, the base portion of the base plate 4 and the spindle fin 3 that rises vertically from the base plate 4 has a base (base plate 4 not shown) in order to make it easier to transfer the conduction heat from the opposite heat transfer surface. Using the existing method of thickening the base part of the spindle-shaped fin 2 so that the transition from the surface of the heat sink surface to the side wall of the spindle-shaped fin 2 standing up is rounded around the boundary part) Thus, the heat dissipation performance may be further improved.

  Next, the operation in this embodiment will be described.

  FIG. 5 is a top view schematically showing the flow of air passing through the heat sink in the second embodiment of the present invention.

  FIG. 5 is a cross-sectional view of the spindle-shaped fin 2 and a general fin (23 in FIG. 6) cut along a plane parallel to the heat radiating surface of the base plate 4 in order to easily understand the difference from the general fin. Contrast is made by using the shape comparison fins 30 provided at the top and bottom. That is, the upper half of the shape comparison fin 30 has a spindle shape and the lower half shows a general flat fin.

  Also, the upper and lower dotted lines shown in FIG. 5 are virtual lines that block the air flow between the upper half spindle-shaped fins or the lower half flat fins. Each wall corresponds to the wall surface of the actual adjacent fin. Comparison is made in the case where air from a fan (not shown) flows between the wall surfaces and toward the fin entrance with a constant air volume m and a constant wind speed v.

  The spindle-shaped fin side shown in the upper half of FIG. 5 has a shorter distance from the wall at the center than the inlet and outlet in the longitudinal direction, so the cross-sectional area of the ventilation channel when air passes through here is Get smaller. As a result, the wind speed locally increases from the entrance to the center of the ventilation channel, and the cooling efficiency can be selectively increased.

  On the other hand, the general flat fin side shown in the lower half of FIG. 5 has a constant distance from the entrance, the exit, and the wall of the central portion, so the wind speed does not increase.

  This will be described in more detail below using mathematical expressions.

  That is, the mass of a substance passing through a plane given per unit time in a general flat fin (the lower half of the shape comparison fin 30 shown in FIG. 5; hereinafter the same) is expressed as a mass flow rate (Mass Flow). Rate: The unit is Kg / s), and the following equation is established.

Mass flow rate m = ρ × S × v (Equation 1),
Here, ρ is the density of the fluid, S is the area of the fluid path, and v is the velocity of the fluid.

  When the flow rate m, density ρ, and speed v of air blown from a fan (not shown) in Formula 1 are constant, Formula 1 is established in a region where the distance from the center of the fin to the wall to be closed is equal.

  That is, if the fin has a flat shape, the velocity S is constant because the area S of the fluid path is constant at any ventilation channel position.

  However, when there is a region where the distance from the center of the fin to the wall to be closed differs in the middle of the longitudinal direction of the fin described in the present embodiment, the following equation is used.

m = ρ × S × v = ρ × S ′ × v ′ (Expression 2)
Here, S ′ is the area of the portion where the ventilation channel in the fin central portion is narrowed, and v ′ is the velocity of the fluid in the portion where the ventilation channel in the fin central portion is also narrowed.

  Formula 2 indicates that the wind speed v can be changed by different cross-sectional areas through which air passes. In other words, reducing the cross-sectional area S of the ventilation channel when passing through the spindle-shaped fin (the upper half of the shape comparison fin 30 shown in FIG. It is shown that it is possible to increase to v ′.

  Specifically, if the cross-sectional area of the ventilation channel is the same at the inlet and outlet, and the cross-sectional area near the center of the ventilation channel is half that of the inlet and outlet, the flow velocity of the air passing through the part is Doubled.

  If the length from the heat radiating surface of the base plate 4 to the open end of the spindle-shaped fin 2 is not extremely short, the amount of air overflowing from the open end of the spindle-shaped fin 2 is not so much, so increase the flow velocity as described above. Can do. If there is a lot of air overflowing from the open end of the spindle-shaped fin 2, a mechanism for closing the open end as described later may be provided.

  Thus, the plurality of spindle-shaped fins can promote the release of heat from the surface.

  Further, the temperature rise (ΔT) of the fluid accompanying the heat generation is expressed by the following formula 3, and it can be seen that the temperature rise is suppressed by the increase of the fluid velocity.

ΔT = Q / (C × A × v × ρ) (Equation 3)
Here, Q is the calorific value of the fluid, C is the specific heat of the fluid, and A is the area of the heat exchange portion of the object along which the fluid flows. That is, if Q, C, A, and ρ are constant, the flow velocity v is doubled when the area S is halved in Equation 2, and therefore, the temperature rise (ΔT) is suppressed to half from Equation 3. .

  Here, FIG. 6 is a top view showing a cooling device using a general heat sink and fan.

  As shown in FIG. 6, the general heat sink 21 has a plurality of general heat sink fins 23 standing on a base plate 22 of a general heat sink. The heat that the general heat sink 21 receives from the heat generating surface such as an LSI on the heat transfer surface and conducts appears as a heat sink region 24 of the general heat sink at a corresponding location on the opposite heat dissipation surface.

  However, in the fin 23 of the general heat sink 21, the heat radiation area 24 of the heat sink 21 has a flat shape, and thus the wind speed v does not increase. That is, in the general heat sink 21, the wind speed cannot be improved only by narrowing the pitch of the plurality of fins.

  Further, in many cases, the high temperature is distributed around the central portion of the heat radiation area 24 of a general heat sink. In the case of the general fin 23, the volume is constant even in the central portion. Compared to the heat conduction, there is little contribution.

  That is, the heat sink in the present embodiment can locally improve the air velocity by making the fins of the heat sink into a spindle shape. At that time, the air from the fan 14 can be accelerated from the moment when it enters the spindle-shaped fin 2, and the speed can be maximized at the central portion of the spindle-shaped fin 2. As a result, the cooling efficiency in the vicinity of the center of the plurality of spindle-shaped fins 2 can be improved.

  In addition, since a heating element such as an LSI generally comes into contact with a heat transfer surface near the center of the heat sink, heat exchange is locally performed near the center of the fin. Therefore, the spindle-shaped fin 2 having a thick central portion in the longitudinal direction and a large volume is more effective in increasing the heat exchange efficiency of the heat sink than simply increasing the surface area including the peripheral portion of the heat sink.

  Further, the cooling efficiency can be selectively improved with respect to the heating element without changing the wind speed of the entire system.

  Further, as a modification, as shown in a perspective view of an application example of the cooling device in the present embodiment shown in FIG. 7, due to restrictions on the structural surface of the device housing, the heat sink surface of the spindle fin 2 When the length to the open end is short, a lid made of the same material as that of the base plate 4 or the spindle-shaped fin 2 as shown in FIG. By applying the end closing lid 15 to the open end of the spindle-shaped fin 2, it is possible to suppress the outflow of air from the open end.

  Thereby, even when the length to the open end of the spindle-shaped fin 2 is short, the air is almost blocked like a tunnel surrounded by the base plate 4, the adjacent spindle-shaped fin 2, and the above-described open end closed lid 15. Since it passes through the ventilated flow path, it is possible to obtain an effect that the flow velocity is easily accelerated toward the center of the spindle-shaped fin 2. At that time, the open end closing lid 15 may be fixed at a position where the open end of the spindle fin 2 is closed using, for example, the base plate 4 and the closing lid stopper 16.

  Note that the above-described open end closing lid 15 may be replaced by a cover or the like which is a part of a device housing (not shown) close to the open end of the heat sink 5. At that time, the same effects as described above can be obtained.

  Further, as another modification, the spindle-shaped fin 2 has a small arrangement interval in the peripheral portion of the heat sink 5 according to the propagation state of the conduction heat from the heat generating portion to the heat radiating surface and the wind speed of the fan. The central part where the high temperature region is concentrated is cooled intensively, and it is not necessary to provide the spindle-shaped fin 2 in the peripheral part where the heat is not concentrated so much, and the material and cost of the heat sink including the fin are reduced. Can do.

  Further, since both ends of the spindle-shaped fin 2 in the longitudinal direction are streamlined, turbulence is generated when the blown air flows in and out as compared to the general heat sink fin 23 shown in FIG. The noise associated with the turbulent flow is reduced.

  FIG. 8 is a top view showing the air flow on the surface of the component mounting board of the information processing apparatus according to the present embodiment.

  As shown in FIG. 8, the computer board 10 includes various devices that can be heat sources such as a heat sink 5 mounted on the CPU 13, an expansion board 6 mounted with an LSI 9, a memory 7, and a storage 8, on the surface of the computer board 10 and It is mounted in the vicinity.

  Further, the CPU 13 appropriately attaches the heat sink 5 to the semiconductor silicon die of the CPU 13 (not shown) or just above a case such as a metal on the CPU surface thermally bonded to the die via an appropriate amount of silicon grease. It is fixed while mounted with a certain pressure.

  The fan 14 is at the same horizontal plane as the surface of the computer board 10 and blows air toward the computer board 10 shown in FIG.

  The air blown from the fan 14 is blown at a predetermined air volume and air velocity from the longitudinal direction (the −Y axis direction shown in FIG. 8) of the spindle-like fin 2 of the heat sink 5 mounted on the computer board 10, for example, mounted on the CPU 13. . Here, the wind speed when flowing into the plurality of spindle-shaped fins 2 from the left toward the drawing and passing through the central portion becomes wind speed v + α12, which is increased by + α.

  In addition, it is desirable that the air blown from the fan 14 be adjusted to a parallel wind so that the device on which the computer board 10 is mounted should be blown uniformly at a constant air volume at a constant air speed. Each device mounted on the substrate 10 may be cooled within a range of the guaranteed operating temperature by a predetermined air volume and speed.

  Note that the air temperature in the computer board 10 causes a decrease in the flow velocity by colliding with components on the substrate, and the air temperature is reduced by heat exchange caused by cooling the components in the middle. The gradual increase in the value can be ignored for the purpose of achieving the purpose of cooling each device to be cooled within the guaranteed operating temperature range.

  Similarly, due to air viscosity, inflow resistance in the ventilation channel, pressure loss, air gas density, and temperature changes due to air compression or decompression, the device to be cooled is cooled within the guaranteed operating temperature range. It can be ignored for the purpose to be achieved.

  That is, according to the heat sink according to the present embodiment, when the air passes through the ventilation channel between the plurality of spindle-shaped fins, the cooling speed can be locally improved by improving the wind speed. it can. Moreover, the selective cooling efficiency of the heating element can be improved without changing the wind speed of the entire system.

  The present invention is applicable to electronic devices including servers and workstations that cool a heat-generating part such as an LSI mounted by forced air cooling, and information processing devices used for industrial equipment such as factory automation.

DESCRIPTION OF SYMBOLS 1 Cooling member 2 Spindle-shaped fin 3 Heat generating body 4 Base plate 5 Heat sink 6 Expansion board 7 Memory 8 Storage 9 LSI
10 Computer board 11 Wind speed v
12 Wind speed v + α
13 CPU
DESCRIPTION OF SYMBOLS 14 Fan 15 Open end obstruction | occlusion lid | cover 16 Closure lid stopper 21 General heat sink 22 General heat sink base plate 23 General heat sink fin 24 General heat sink heat dissipation area 30 Shape comparison fin

Claims (9)

  A spindle-shaped fin having one end and the other end in the longitudinal direction, the width of the central portion in the longitudinal direction being longer than the width in other portions, and the cross-sectional shape parallel to the longitudinal direction being substantially spindle-shaped, A cooling member characterized in that a plurality of sheets are erected in a single row in a direction perpendicular to the longitudinal direction on the surface.   A base plate having a predetermined area and thickness and a predetermined thermal conductivity is provided between the heating element and the spindle-shaped fin, and the base plate and the spindle-shaped fin have the same or equivalent thermal conductivity. 2. The cooling member according to claim 1, wherein the cooling member is an integral or integrally formed heat sink.   The cooling member according to claim 1, a ventilation channel that is a gap including a surface including a surface of the heating element and an adjacent wall surface of the plurality of spindle-shaped fins, A cooling device comprising: air blowing means for blowing air so that air flows from one end portion in the longitudinal direction toward the other end portion.   The air blowing means is provided in the heat sink when air is blown at a predetermined air volume and wind speed over an entire control board of an electronic device on which a plurality of types of heat generators including the heat generator on which the heat sink is mounted is mounted. The air flow is blown so that air flows from one end of the longitudinal direction of the spindle-shaped fin to the other end. The cooling device as described.   The air blower means the control board of the electronic device such that a plurality of types of heat generating elements including the heat generating element on which the heat sink mounted on the control board of the electronic equipment is placed within a predetermined operating temperature range. The cooling device according to any one of claims 1 to 4, wherein the air is blown at a predetermined air volume and speed.   The heat sink is connected to any member of the heat sink so that air blown from the blower means does not overflow from the open end of the spindle fin when the blown air passes through the ventilation channel. The cooling device according to any one of claims 1 to 5, wherein an open end closing lid that closes the open end locked to any member of the heat sink is made of the same material.   The cooling device according to any one of claims 1 to 6, wherein the base plate and a base portion of each spindle-shaped fin standing on the base plate have a skirt shape. A spindle-shaped fin having one end and the other end in the longitudinal direction, the width of the central portion in the longitudinal direction being longer than the width in other portions, and the cross-sectional shape parallel to the longitudinal direction being substantially spindle-shaped, In the surface, in a direction perpendicular to the longitudinal direction, a plurality of sheets are erected so as to form a single row,
The heating element is cooled by blowing air from a longitudinal end of the plurality of spindle-shaped fins erected from the longitudinal direction to the other end by a blowing means. Cooling method. Utilizing the fact that the flow velocity of the air blown from the blowing means increases at the location where the gap is narrowed by the adjacent wall surfaces of the plurality of spindle-shaped fins facing each other in a convex curve shape, The method for cooling a heating element according to claim 8, wherein the cooling efficiency by the spindle-shaped fins at a location is improved as compared with other locations.

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