JP2005286130A - Mounting structure of cooling device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the mounting structure of a cooling device, whereby superior and stable contact with high accuracy can be obtained between a heat generating body and the cooling device, while attaining low profile for the cooling device. <P>SOLUTION: An energizing member for energizing and press-contacting a cooling module 4 to an MPU 3 employs no cylindrical coil nor a plate spring, but rather employs a conical coil spring 42. Thus, the height directional dimension can be reduced more than the case with the use of the cylindrical coil spring 26, and low profile of a fitting mechanism 41, and then that of the cooling module 4 can be attained. Further, the conical coil spring 42 can easily set a weight applied to a side of the MPU 3 and apply a stable weight thereto, in comparison with the case with the plate spring 31. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a mounting structure for a cooling device that is mounted in a thin housing such as a notebook personal computer and efficiently cools a heating element provided inside the housing while being thin.

  Conventionally, heat generating parts such as MPU (microprocessor unit) are used as functional parts inside the casing of thin electronic devices such as notebook computers, and in order to prevent a significant temperature rise of such heat generating parts, A cooling device having a heat receiving part and a heat radiating part is incorporated.

  FIG. 5 shows such a cooling device, and a similar structure is disclosed in Patent Document 1, for example. In the figure, reference numeral 1 denotes a case of a notebook personal computer. An MPU 3 is mounted and fixed on a substrate 2 housed inside the case 1, and a horizontally long rectangular shape for cooling the MPU 3 is provided above the MPU 3. The cooling device 4 is arranged.

  The cooling device 4 includes a case 5 that is integrally die-cast with a material having excellent thermal conductivity such as aluminum, copper, and magnesium, and a cover 7 that forms a fan housing portion 6 that is a heat radiating portion together with the case 5. Are provided as the outer member. The heat receiving portion 8 formed on one side of the case 5 includes a connecting portion 8A having a trapezoidal cross section with the central portion slightly protruding downward, and the connecting portion 8A is thick. In addition, the fan housing portion 6 has the other side of the case 5 as an upper surface portion, and a cover 7 made of a metal plate material as a lower surface portion, and a space 9 serving as a wind tunnel is formed therebetween, in which a plurality of fan blades are formed. A blower 13 comprising a rotatable fan 11 in which 10 is integrally formed on the outer peripheral side surface of a cup-shaped rotor (not shown) and a drive unit 12 that applies a rotational force to the fan 11 is attached. ing. Each of the case 5 and the cover 7 facing the rotation axis direction of the blower 13 is provided with intake holes 14 and 15 for taking air into the space 9 and orthogonal to these intake holes 14 and 15. An exhaust hole 16 is provided in the radial direction of the blower 13.

  A plurality of substrates 2 to which the MPU 3 is fixed are formed on the bottom surface of the housing 1 and are placed on the top surface of the projection 19 having the screw holes 18, and between the top surface of the MPU 3 and the connection portion 8 </ b> A of the heat receiving unit 8. A heat conducting rubber 20 having elasticity is provided. In addition, in order to thermally connect the MPU 3 and the heat receiving portion 8, the heat receiving portion 8 is provided with an attachment mechanism 21 for attaching the cooling device 4 to the housing 1 that is the attached portion. The substrate 2 is provided with an insertion hole 2A through which a male screw portion 25A of a screw 25 described later is inserted at a position corresponding to the screw hole 18.

  Here, the structure of the attachment mechanism 21 will be described. A recess 24 having a circular bottom hole 23 at the center of the bottom portion is formed around the heat receiving portion 8 so as to correspond to the screw holes 18 of the protrusions 19, respectively. A stud 26 with a mounting screw 25 is provided in the recess 24 so that it can be inserted into the bottom hole 23. The stud 26 includes a cylindrical portion 26A whose lower end passes through the bottom hole 23 and is in contact with the upper surface of the substrate 2, and a flange portion 26B that is formed in the upper end radial direction of the cylindrical portion 26A and is inserted into the recess 24. A cylindrical coil spring 28 is provided between the bottom surface of the recess 24 and the lower surface of the flange portion 26B to press the cooling device 4 against the MPU 3 against the bias of the heat conducting rubber 20. The lower end of the male screw portion 25A passes through the cylindrical portion 26A of the stud 26 and the insertion hole 2A provided in the substrate 2, and is screwed into the screw hole 18 formed in the housing 1. . Further, 29 is a retaining ring that is located below the recess 24 and is attached to the lower end portion of the cylindrical portion 26A. This is when the stud 26 is attached with the cylindrical coil spring 28 interposed in the recess 24 of the heat receiving portion 8. This is to prevent the stud 26 from jumping out of the recess 24 due to the elastic force of the cylindrical coil spring 28.

  In the above configuration, the heat reaching the heat receiving portion 8 from the MPU 3 via the heat conducting rubber 20 is conducted to the fan housing portion 6 side by the case 5 made of a member having good heat conductivity, and the fan 12 is driven by the drive portion 12. When the fan 11 in the storage unit 6 rotates, the air around the intake holes 14 and 15 of the cooling device 4 in the housing 1 passes through the intake holes 14 and 15 while taking the heat conducted to the case 5. It is sucked into the space 9 in the storage unit 6. Then, the air taken into the space 9 is smoothly discharged from the exhaust hole 16 in a direction orthogonal to the intake holes 14 and 15 to the outside of the cooling device 4 and the casing 1. Thereby, the temperature rise of MPU3 in the housing | casing 1 can be suppressed by the cooling device 4. FIG.

  Further, when the male screw portion 25A of the mounting screw 25 is screwed into the screw hole 18 of the housing 1 with the substrate 2 and the stud 26 placed on the protrusion 19 of the housing 1, the mounting screw 25 is mounted in the recess 24 of the heat receiving portion 8. The stud 26 is fixedly mounted on the projection 19 of the housing 1 together with the substrate 2. At this time, due to the elastic force of the cylindrical coil spring 28 constituting the attachment mechanism 21, the heat receiving portion 8 of the cooling device 4 is brought into close contact with the MPU 3 with an appropriate load, and the heat from the MPU 3 is efficiently applied to the connecting portion 8A of the heat receiving portion 8. I can tell you well.

FIG. 6 shows another example in which a plate spring 31 is used in place of the cylindrical coil spring 28. The leaf spring 31 is elastically deformed around a portion that contacts the protrusion 32 provided on the upper surface of the heat receiving portion 8 as a fulcrum, and a cylindrical portion 26A of each stud 26 is provided around the leaf spring 31. A hole 33 through which is inserted is formed. Further, here, the leaf spring 31 is placed on the upper surface of the heat receiving portion 8, so that a through hole 34 having substantially the same shape as the hole 33 is provided in place of the recess 24, and the cylindrical portion 26A of the stud 26 has a lower end thereof. The portion passes through the through hole 34 and is in contact with the upper surface of the substrate 2. In this case, the cylindrical portion 26A of the stud 26 is inserted through the hole 33 of the leaf spring 31 and the through hole 34 of the heat receiving portion 8 in this order, and the substrate 2 and the stud 26 are placed on the protrusion 19 of the housing 1, A male screw portion 25A of the mounting screw 25 is screwed into the screw hole 18 of the housing 1. As a result, the elastic force of the leaf spring 31 acts so that the heat receiving portion 8 of the cooling device 4 is in close contact with the MPU 3 with an appropriate load, and the heat from the MPU 3 is connected to the heat receiving portion 8 as in the case of FIG. It can be efficiently transmitted to the part 8A.
JP 2001-85585 A

  However, in the cooling device mounting structure shown in FIG. 5, the spring material (the wire forming the spring) that is the base material of the cylindrical coil spring 28 spirals at the same coil diameter regardless of the position in the height direction. Therefore, the urging member that urges and presses the cooling device 4 against the MPU 3 needs a certain height, and there is a limit to making the cooling device thinner.

  In order to avoid such a problem, it is conceivable to adopt a structure using the leaf spring 31 shown in FIG. 6, but from the manufacturing accuracy of the leaf spring 31, compared to a structure using the cylindrical coil spring 28, It was difficult to set the load to be applied to the MPU 3 side, and furthermore, there was a variation in load during mass production, and stable thermal connection could not be realized.

  Accordingly, the present invention has been made in view of the above-described problems, and has a cooling device mounting structure capable of obtaining a good and stable and accurate contact between the heating element and the cooling device while reducing the thickness of the cooling device. The purpose is to provide.

  In the mounting structure of the cooling device according to claim 1 of the present invention, a conical coil spring whose coil diameter changes in the height direction is used as the biasing member that biases and presses the heat receiving portion of the cooling device toward the heating element. The dimensional difference in the height direction can be reduced as compared with the cylindrical coil spring, and the mounting mechanism, and thus the cooling device can be made thinner. And if it is a conical coil spring instead of a leaf | plate spring, the setting of the load added to the heat generating body side is easy, and the stable load can be applied.

  In the cooling device mounting structure according to claim 2, since the heat receiving portion that takes away heat from the heating element is formed of a sheet metal member, the heat receiving portion can be further thinned, and the biasing member is a conical coil spring. Together with this, the cooling device can be made thinner.

  The cooling device mounting structure according to claim 3 is characterized in that the cooling device is provided with a heat transport portion. Thereby, the heat from a heat generating body can be guide | induced to a ventilation part by a heat transport part, and cooling performance improves. Moreover, since the heat transport part is excellent in thermal responsiveness, for example, even when the temperature of the heating element rapidly increases, the temperature increase can be effectively suppressed.

  According to the mounting structure of the cooling device in claim 1, it is possible to obtain a good and stable good contact between the heating element and the cooling device while reducing the thickness of the cooling device.

  According to the mounting structure of the cooling device in claim 2, the cooling device can be further reduced in thickness.

  According to the cooling device mounting structure of the third aspect, the cooling performance of the cooling device can be enhanced, and even when the temperature of the heating element rises rapidly, the temperature rise can be effectively suppressed.

  Embodiments of the cooling device mounting structure according to the present invention will be described below with reference to the accompanying drawings. The cooling module as the cooling device in each embodiment is used for a thin electronic device such as a notebook personal computer, and the same parts as those in FIGS. However, the description of the common part is duplicated and will be omitted.

  1 and 2 show a first embodiment of the present invention. On the bottom surface of the housing 1, a plurality (four in this embodiment) of projecting portions 19 provided with screw holes 18 are provided. A substantially rectangular substrate 2 is placed on the projecting portion 19, and an MPU 3 that generates heat in an energized state is attached to the substrate 2. A through hole 2 </ b> A is provided at a position corresponding to the screw hole 18 of the substrate 2. A heat sink portion 8 on one side of the cooling module 4 is disposed above the MPU 3 via a heat conducting rubber 20, and a space 9 is provided in the fan housing portion 6 on the other side of the cooling module 4. The air blower 13 is attached to the space 9. The case 5 of the cooling module 4 is integrally formed by die-casting with a good heat conductive material such as aluminum, copper, or magnesium. However, other materials may be used as long as the heat conductivity is excellent. Further, the forming method is not limited to die casting, and other methods may be used. The above points are common to FIGS. 5 and 6 shown in the conventional example.

  Reference numeral 41 denotes an attachment mechanism for attaching the cooling module 4 to the housing 1 which is an attachment portion. The mounting mechanism 41 here is not a cylindrical coil spring 26 or a leaf spring 31 as in the conventional example, but a coil diameter as a biasing member for biasing and pressing the heat sink portion 8 of the cooling module 4 to the MPU 3 that is a heating element. It is noted that a conical coil spring 42 is used which gradually decreases as the angle increases upward.

  More specifically, a recess 24 having a circular bottom hole 23 at the center of the bottom is formed around the heat sink portion 8, and a stud 26 with a mounting screw 25 is inserted into the bottom hole 23 in the recess 24. Provided possible. The conical coil spring 42 is provided between the bottom surface of the recess 24 and the flange portion 26B of the stud 26 with the large-diameter side of the coil portion facing downward while being inserted through the cylindrical portion 26A of the stud 26. . The lower end of the male screw portion 25A of the mounting screw 25 passes through the cylindrical portion 26A of the stud 26 and the insertion hole 2A provided in the substrate 2, and is screwed into the screw hole 18 formed in the housing 1. The conical coil spring 42 is interposed between the stud 26 fixed to the heat sink portion 8 and the connecting portion 8A of the heat sink portion 8 is pressed and adhered to the MPU 3 side. In the present embodiment, the mounting screw 25 and the stud 26 are formed as separate members, but may be integrated.

  A procedure for attaching the cooling module 4 to the housing 1 in the above configuration will be described. First, conical coil springs 42 are respectively arranged in the four recesses 24 formed in the heat sink portion 8 of the cooling module 4 with the large-diameter portion facing down, and the flange portion 26B is facing up, in the central portion of the conical coil spring 42. Insert the stud 26. Next, the flange portion 26 </ b> B of the stud 26 is pushed in, the conical coil spring 42 is compressed, and the lower end of the stud 26 is protruded from the bottom hole 23 of the recess 24. A ring-shaped retaining ring 29 is inserted into the protruding lower end of the stud 26 to restrict the upward movement of the stud 28 so that the stud 28 does not come out of the recess 24 due to the bias of the conical coil spring 425. Finally, the screw hole 18 of the protrusion 19 and the through hole 2A of the substrate 2 are aligned, and the substrate 2 to which the MPU 3 is attached is placed on the housing 1, and a heat conducting rubber 20 or between the MPU 3 and the connecting portion 8A is placed. The male screw portion 25A of the mounting screw 25 protruding from the lower end of the stud 28 is screwed into the screw hole 18 of the protrusion 19 with the thermal grease interposed therebetween. At this time, the conical coil spring 42 contracts as the mounting screw 25 is screwed in, and the heat sink portion 8 is pressed against the MPU 3 side with a predetermined force by the elasticity of the conical coil spring 42.

  FIG. 3 shows the difference in height of the cooling module 4 when the cooling module 4 is attached to the housing 1 using the cylindrical coil spring 26 shown in FIG. 5 and the conical coil spring 42 shown in FIG. Is. As shown in the figure, the height of the cooling module 4 with respect to the lower end of the stud 26 when the conical coil spring 42 is used is Δh compared to the case where the cylindrical coil spring 16 having the same thickness and the same number of turns is used. Low. The reason is that the height of the cylindrical coil spring 16 cannot be structurally less than the product of the wire diameter and the number of turns. This is because the height dimension can be formed below the combined value. In addition, in the case of the conical coil spring 42, the load applied to the MPU 3 side can be easily set without requiring manufacturing accuracy as in the case of the leaf spring 31 of the conventional example, and the load variation during mass production is small. As a result, it is possible to reduce the thickness of the cooling module 4 and to achieve a stable and accurate thermal connection to the MPU 3.

  As described above, in the present embodiment, as a cooling device that integrally includes the air blower 13 that is a blower, the heat sink portion 8 that is a heat receiving portion, and the fan housing portion 6 that is a heat radiating portion, the MPU 3 that is a heating element is cooled. The cooling module 4 and an attachment mechanism 41 that attaches the cooling module 4 to the housing 1 of the personal computer, which is an attachment portion, are provided in the attachment mechanism 41 with an urging member that urges and cools the cooling module 4 against the MPU 3. In the mounting structure of the cooling module 4, the conical coil spring 42 is used as an urging member in at least one place of the mounting mechanism 41.

  In this case, since the conical coil spring 42 whose coil diameter changes in the height direction is used as the urging member that urges and presses the cooling module 4 toward the MPU 3, the dimension in the height direction is larger than that of the cylindrical coil spring 26. The difference can be reduced, and the attachment mechanism 41, and thus the cooling module 4, can be made thinner. Moreover, if the conical coil spring 42 is used instead of the leaf spring 31, the load applied to the MPU 3 side can be easily set, and a stable load can be applied. Therefore, it is possible to obtain an accurate and stable good contact between the MPU 3 and the cooling module 4 while reducing the thickness of the cooling module 4.

  Next, a second embodiment of the present invention will be described with reference to FIG. In addition, the same code | symbol is attached | subjected to the same part as the said 1st Embodiment, and since the description of the common location overlaps, it abbreviate | omits.

  In the second embodiment, a sheet metal member 51 that is appropriately bent is used in place of the case 5 that forms the upper surface portions of the heat sink portion 8 and the fan housing portion 6, and cooling is further performed on the upper surface of the sheet metal member 51. The point from which the heat pipe 52 for improving performance is arrange | positioned differs from 1st Embodiment.

  The heat pipe 52 forms an outer tube portion made of copper or the like having excellent heat conductivity, and a small amount of working fluid (not shown) is injected into the inside of the pipe, and this working fluid is circulated inside the tube body. By doing so, a cooling effect can be obtained. By attaching the heat pipe 52 in this way, not only the sheet metal member 51 but also the heat pipe 52 can guide the heat of the MPU 3 to the blower 13 side, and the cooling performance can be improved. Moreover, since the heat pipe 52 is excellent in heat responsiveness, even when the temperature of the MPU 3 that is a heat generation source is rapidly increased, the temperature increase can be effectively suppressed.

  Further, the outer members of the cooling module 4 are each formed by a cover 7 made of a metal plate material or a sheet metal member 51. Therefore, the cooling module 4 can be made thinner than that by die casting, and it is possible to further reduce the thickness of a thin electronic device such as a personal computer using this.

  In the configuration of FIG. 4, the heat sink portion 8 and the fan accommodating portion 6 that accommodates the air blower 13 may be separated, and in that case, the heat pipe 52 and the fan accommodating portion 6 are thermally connected by the heat pipe 52. do it. Further, the heat pipe 52 is optional and may have a structure without the heat pipe 52. In addition, the procedure for attaching the cooling module 4 to the housing 1 and the operation of the conical coil spring 42 are as described in the first embodiment.

  According to the present embodiment, since the heat sink portion 8 that takes away heat from the MPU 3 is formed by the sheet metal member 51, the heat sink portion 8 can be further thinned, and this is in combination with the fact that the biasing member is the conical coil spring 42. Thus, the cooling module 4 can be further reduced in thickness.

  In addition, since the cooling module 4 includes the heat pipe 52 as a heat transport section, the heat pipe 52 can guide the heat from the MPU 3 to the fan housing section 6 where the blower 13 is provided, thereby improving the cooling performance. . Moreover, since the heat pipe 52 is excellent in heat responsiveness, for example, even when the temperature of the MPU 3 rapidly increases, the temperature increase can be effectively suppressed.

  In addition, this invention is not limited to the said embodiment, A various change is possible. For example, in the above embodiment, the conical coil springs 42 are used at four locations around the heat sink portion 8, but are not limited to four locations. For example, only one location is used in relation to other structures. Also good.

It is a top view which shows the attachment structure of the cooling device in 1st Embodiment of this invention. It is sectional drawing of a cooling device same as the above. It is the figure which showed the difference in the height of an attachment structure at the time of using a cylindrical coil spring and a cone coil spring. It is sectional drawing which shows the attachment structure of the cooling device of 2nd Embodiment of this invention. It is sectional drawing which showed the attachment structure of the cooling device in a prior art example. It is sectional drawing which showed the other attachment structure of the cooling device in a prior art example.

Explanation of symbols

3 MPU (heating element)
4 Cooling module (cooling device)
6 Fan storage part (heat dissipation part)
8 Heat sink (heat receiving part)
13 Blower (Blower)
41 Mounting mechanism
42 Conical coil spring (biasing member)
52 Heat pipe (heat transport section)

Claims (3)

  A cooling unit that integrally includes a blower unit, a heat receiving unit, and a heat radiating unit and cools the heating element, and an attachment mechanism that attaches the cooling unit to the mounted part. The heating unit is provided with the heat receiving unit of the cooling unit. In the mounting structure of the cooling device provided with an urging member in pressure contact with the mounting mechanism, a conical coil spring is used as the urging member in at least one place of the mounting mechanism. .   The cooling device mounting structure according to claim 1, wherein the heat receiving portion is formed of a sheet metal member. The cooling device mounting structure according to claim 1, wherein the cooling device includes a heat transport portion.

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