JP4549659B2 - Heat sink, housing and cooling fan, and electronic device having heat sink - Google Patents

Description

  The present invention generally relates to a heat dissipation mechanism provided in an electronic device, and more particularly, to a heat sink that releases heat generated from a heat generating circuit element (heat generating element) mounted on the electronic device and a method for manufacturing the heat sink. The electronic device of the present invention includes a portable electronic device such as a notebook personal computer (PC), a personal digital assistant (PDA), a portable game device, and various drives, a display-integrated or slim desktop PC, and a word processor. Space-saving electronic devices such as non-space-saving desktop PCs and word processors, and image forming apparatuses such as printers, fax machines, and copiers. The present invention is suitable for a heat dissipation mechanism of various circuit elements mounted on a notebook PC motherboard, for example.

  Notebook PCs are widely on the market as typical portable electronic information terminals. A notebook PC motherboard (or main board) is mounted with circuit elements such as a CPU socket, various memories (sockets), a chip set, an expansion slot, and a BIOSROM, and directly affects the performance and functions of the PC.

  In recent years, notebook PCs tend to increase the number of heat generating elements and the amount of heat generated from such circuit elements as the various circuit elements mounted on a motherboard increase in speed and functionality. Therefore, a cooling device called a heat sink is provided on the mother board in order to thermally protect the heat generating elements and other circuit elements mounted on the mother board directly or via a socket or the like.

  The heat sink typically has cooling (or heat radiating) fins made up of a large number of highly heat conductive members (fin assemblies), and cools the heating elements by natural air cooling. However, the amount of heat generated by the heating elements in recent years tends not to be able to cope with natural air cooling. Therefore, a heat sink with a fan that further includes a cooling fan has been proposed in order to enhance the cooling effect of the heat sink. The heat sink with fan forcibly cools the heat sink by the air flow generated by the fan. Conventional heat sinks with fans have the largest amount of heat generated from the CPU, and are therefore typically provided above the CPU of the motherboard.

  In order to reduce the size and increase the rigidity of the heat sink with a fan, a cooling fin, a base that forms the bottom surface of the cooling fin and enables heat transfer from the heating element to the cooling fin, and a storage portion that stores the cooling fan, Are integrally formed by die casting. Such an integrated heat sink can efficiently conduct heat from the connection surface (heat receiving surface) between the heating element and the base to the cooling fin, and thus has high heat exchange performance. There has also been proposed a heat sink with a fan that saves space by arranging cooling fins on the same plane as the cooling fan (for example, cooling fins around the cooling fan). This arrangement is suitable for recent notebook PCs that are required to be thin (low profile).

  However, the conventional integrated heat sink with a fan cannot be finely adapted to a heating element having various shapes and calorific values and installation places having various shapes and dimensions at the time of installation. For example, if you want to use a larger cooling fan to increase the cooling efficiency, or if you want to change the cooling efficiency by changing the shape of the fin assembly that makes the cooling fin from aluminum to copper or changing the fin assembly that forms the cooling fin, There are cases where it is desired to change the shape and dimensions of the housing in accordance with the shape and dimensions of the element and the installation location. However, in any case, the conventional integrated heat sink with a fan needs to replace the entire heat sink uneconomically. For example, if cooling fins are arranged around the cooling fan, the cooling fan cannot be replaced with a larger one, and the shape of the housing cannot be changed while leaving the cooling fins and cooling fans as they are. Furthermore, it is often impossible to change only the cooling fins of the aluminum die cast heat sink with fan to copper. As a result, a different heat sink must be designed for each electronic device, resulting in an increase in the cost of the electronic device.

  Similarly, the conventional heat sink with an integrated fan is uneconomical because the entire heat sink must be replaced even if one of the components is damaged.

  SUMMARY OF THE INVENTION Accordingly, it is a general object of the present invention to provide a new and useful heat sink that solves such conventional problems, a method for manufacturing the same, and an electronic device having the heat sink.

  More specifically, the present invention relates to a heat sink that can be finely and inexpensively adapted to a heating element having various shapes and calorific values, installation locations of various shapes and dimensions, and the like during installation and replacement. It is an exemplary object to provide a manufacturing method and an electronic device having the heat sink.

  In order to achieve the above object, a heat sink as an exemplary embodiment of the present invention includes a housing, a cooling fin that is detachably coupled to the housing, receives heat from the heat generating portion, and dissipates the heat generating portion. Have Alternatively, the heat sink is detachably coupled to the housing, the heat receiving surface that receives heat from the heat generating portion, and the cooling that is formed on the back side of the heat receiving surface to dissipate the heat generating portion. And a base having fins. Furthermore, the cooling fin is removable from the base. In such a heat sink, since the casing and the cooling fin can be separated, it is easy to replace the casing or the cooling fin alone. In addition, since the cooling fin and the base can be separated, each element can be easily replaced. The replacement here includes not only changing the damaged housing and cooling fins, but also changing the material and shape (changing the cooling fin from aluminum to copper or changing the shape of the fin assembly that constitutes the cooling fin) It also includes the case of doing.

  The heat sink may further include a cooling fan that forcibly cools the cooling fin and is connected to the housing, and the cooling fan and the cooling fin are disposed on the same plane. In this case, the heat sink (heat sink with fan) enhances the cooling function and the cooling fin and the cooling fan are arranged on the same plane, which contributes to a reduction in the thickness of the heat sink itself.

  The housing as an exemplary aspect of the present invention is characterized by having a storage portion that detachably stores cooling fins that dissipate heat from the heat generating portion for heat dissipation. Since such a case is formed independently of the cooling fin, it can be designed freely according to the size and shape of the installation location in the electronic device, and the case and the cooling fin are developed independently. be able to.

  The housing can further accommodate a cooling fan that forcibly cools the cooling fin in the accommodating portion, and the cooling fan and the cooling fin are arranged on the same plane. In this case, since the cooling fin and the cooling fan are arranged on the same plane, the casing contributes to a reduction in thickness of the casing itself.

  The cooling fin as an exemplary aspect of the present invention includes a fin assembly including a plurality of fins that dissipate heat from the heat generating portion, and a housing having a storage portion that detachably stores the fin assembly. And a connecting portion for connecting. Since these cooling fins are formed independently of the housing, they can be designed freely according to the dimensions and shape of the heating elements and the dimensions and shape of the installation location, and the housing and cooling fins are independent. And can be developed. The cooling fin may further include a base portion that forms a heat receiving surface.

  The heat sink manufacturing method as an exemplary aspect of the present invention includes a step of forming a casing, a step of forming a base having a cooling fin and separably coupled to the casing, the casing and the casing And a step of detachably connecting the base. Since such a manufacturing method manufactures the casing and the base separately and connects them, any type can be selected when both have a plurality of types having different dimensions, shapes, materials, etc. Heat sinks with different cooling performance can be manufactured. In the step of forming the base portion, the cooling fin may be formed by a forging method or a pressing method. In this case, a high-precision and high-strength base can be formed.

  The manufacturing method of the heat sink may further include a step of attaching a cooling fan to the housing, and the step includes arranging the cooling fan and the cooling fin on the same plane. In this case, since the cooling fin and the cooling fan are arranged on the same plane, the heat sink contributes to the thinning of the heat sink itself.

  An electronic apparatus as an exemplary aspect of the present invention is an electronic apparatus that includes a printed circuit board on which a heat generating unit is mounted, and a heat sink that is provided on the printed circuit board and cools the heat generating element. And a cooling fin that is detachably coupled to the body and receives heat from the heat generating portion to dissipate the heat generating portion. Furthermore, the electronic device may further include a cooling fan that forcibly cools the cooling fin and is connected to the housing, and the cooling fan and the cooling fin are arranged on the same plane. Since such an electronic device has the above-described heat sink, individual replacement of each element is easy, and therefore it is possible to meet the demands of the electronic device in a detailed and economical manner.

  Other objects and further features of the present invention will become apparent from the embodiments described below with reference to the accompanying drawings.

  According to the heat sink, the manufacturing method thereof, and the electronic device of the present invention, a plurality of types of housings and cooling fins are independently developed, and the types that meet the requirements of size, shape, cooling efficiency, etc. are arbitrarily combined. Therefore, it is possible to respond to the above request in a detailed and economical manner. In addition, it is more economical than exchanging the whole because only the elements that need to be exchanged need to be exchanged.

  Hereinafter, with reference to FIG. 1 thru | or FIG. 4, the thermal radiation mechanism 100 which has the heat sink 110 with a fan as an exemplary aspect of this invention is demonstrated. The heat dissipation mechanism 100 of this embodiment is mainly composed of the heat sink 110 with a fan of the present invention. As an element of the heat dissipation mechanism, a mother board 160 provided with a through hole 166 may be selectively added. The heat dissipation mechanism 100 includes at least cooling fins 140. Here, FIG. 1 is an exploded perspective view of a heat dissipation mechanism 100 as an exemplary embodiment of the present invention. FIG. 2 is a perspective view showing the back surface of the motherboard 160 of the heat dissipation mechanism 100. FIG. 3 is a schematic enlarged perspective view showing the fan-mounted heat sink 110 shown in FIG. FIG. 4 is an exploded perspective view showing the inside of the heat sink with fan 110 as an exemplary embodiment of the present invention.

  As the heat dissipation mechanism 100 of the present embodiment, a CPU 150 (or MPU, which is indicated by a dotted line in FIG. 1, means a processor in a broad sense, and will be treated similarly in the present application hereinafter). In order to cool, a heat sink 110 with a fan for the CPU 150 provided in thermal contact with the CPU 150 is used. If necessary, the heat dissipation mechanism 100 may include a mother board 160 provided with a through hole 166. The heat sink with fan 110 includes a housing 120, a cooling fan 130, and a plurality of cooling fins 140 (FIG. 4).

The housing 120 is a substantially rectangular parallelepiped frame made of a high thermal conductive material such as aluminum, copper, aluminum nitride, artificial diamond, plastic, and the like, and includes an upper surface 122, a mounting hole 123a, a mounting groove 123b, and a lower surface. 124, an intake port 125, an end surface 126, an exhaust port 127, and a storage portion 128. Furthermore, referring to FIG. 4, the lower surface 124 includes a base portion 144 to which the plate-like fins 142 are connected. The lower surface 124 and the base portion 144 are preferably formed flat in order to reduce the contact thermal resistance with the CPU 150. The heat sink with fan 110 is manufactured by sheet metal processing, aluminum die casting, or other methods. If the housing 120 is made of plastic, it may be formed by, for example, injection molding. A part of the housing 120 (for example, the cooling fan 130 and the cooling fin 140) may be separable.

  Here, the intake port 125 is provided on both the upper surface side 122 and the lower surface side 124 of the housing 120. As shown in FIG. 3, the air inlet 125 passes through the upper surface 122 and the lower surface 124. More clearly, as shown in FIG. 4, it can be seen that an intake port 125 is also provided on the lower surface side 124. The heat sink 110 with fan (FIGS. 1 and 3) can suck air from both the upper and lower surfaces 122 and 124 of the heat sink 110 with fan.

For convenience of replacement or maintenance of the cooling fan 130 and / or the cooling fin 140, the upper surface 122 of the housing 120 is configured to be removable from the main body including the lower surface 124 as a lid, as shown in FIG. It is preferable. Alternatively, a heat sink without a lid shown in FIG. 4 can be used instead of the heat sink with fan 110 shown in FIG. 1, but a lid is provided to reduce noise associated with the rotation of the cooling fan 130. It is preferable. Furthermore, as shown in FIG. 4, the heat sink 110 with a fan of the present invention can remove the cooling fin 140 from the lower surface 124. That is, the heat sink 110 with a fan of the present invention is manufactured by dividing the lower surface 124 and the cooling fin 140.

The housing 120 stores the cooling fan 130 and the cooling fins 140 in the storage portion 128. Housing portion 128 has a rectangular section 128b for accommodating the semi-circular portion 128a and the cooling fins 140 for accommodating the cooling fan 130. The storage unit 128 also functions as a wind tunnel space through which the air flow generated by the cooling fan 130 passes. Since the housing 120 can also radiate heat from the surface thereof, if necessary, the upper and lower surfaces 122 and 124 and other surfaces may be projected to increase the surface area, thereby enhancing the heat radiation effect.

  In FIG. 1, the mounting hole 123 a and the mounting groove 123 b penetrate the upper and lower surfaces 122 and 124 and engage with the screw 170. The screw 170 may be hollow so that the CPU 150 provided on the motherboard 160 can be engaged with a pin 172 that passes through the installation socket 151. The socket 151 makes the CPU 150 replaceable. Alternatively, the screw 170 passes through a hole (not shown) of the motherboard 160 and is fixed to the motherboard 160 via a nut (not shown) if necessary. As a result, the housing 120 is fixed to the mother board 160 via the mounting holes 123a, the mounting grooves 123b, and the screws 170. However, the means for thermally connecting the casing 120 and the CPU 150 is not limited. For example, the two can be bonded by heat conductive adhesive or half-dipping (a cream half uses a reflow oven, etc.), or a mounting pin having a slit head at the tip is inserted from a later-described surface 164 of the motherboard 160. Then, coil springs may be applied to the portions protruding from the mounting holes 123a and the mounting grooves 123b and fixed.

  In FIG. 1, FIG. 3 and FIG. 4, the intake port 125 passes through the upper and lower surfaces 122 and 124 to allow the cooling fan 130 to communicate with the outside. Further, the air inlet 125 may communicate with a through hole 166 described later of the motherboard 160. An exhaust port 127 is provided in the end face 126 and communicates with the cooling fan 130 and the cooling fin 140. The air inlet 125 has a function of introducing warm air from the heat generating elements widely mounted on the motherboard 160 into the housing 120 together with heat generation from the CPU 150.

  As a result, the intake port 125 can introduce warm air on the surface 162 side, which will be described later, of the motherboard 160 on the upper and lower surfaces 122 and 124 into the housing 120, and will be described later on the motherboard 160 via the through hole 166 on the lower surface 124. Warm air from the surface 164 can be introduced into the housing 120. That is, the cooling fan 130 can be introduced into the housing 120 from both sides (122 and 124 side). The introduced warm air is supplied to cooling fins 140, which will be described later, by a cooling fan 130, and is exhausted from an exhaust port 127 after undergoing heat exchange. The introduced warm air is cooled by such heat exchange. The exhaust port 127 communicates with a heat-dissipating sheet metal (not shown) built in a side portion 225 of a notebook PC 200 described later or the vicinity of an exhaust port provided on the side portion 225. Further, as described above, warm air heat is also released from the surface of the housing 120.

  In this embodiment, the intake port 125 has such a size that the entire cooling fan 130 is exposed to the outside, but the size can be arbitrarily set, and if necessary, a plurality of holes can be provided. (For example, a mesh structure) may be used. Furthermore, although the intake port 125 is provided in the upper and lower surfaces 122 and 124 as shown in FIG. 3, it may be provided only in one of them.

  If necessary, the housing 120 may be, for example, a hollow having a bottom having a lower surface 124 and containing cooling water (water or other refrigerants (eg, freon, alcohol, ammonia, galden, chlorofluorocarbon, etc.)). May be configured. In addition, it is more effective to insert a mesh (or wick) into the hollow portion and reflux the cooling water by capillary action. Further, the housing 120 may be connected to an external heat pipe or the like if necessary. Here, the heat pipe has a pipe with a height difference formed of aluminum, stainless steel, copper or the like. The pipe is provided with a wick material formed of glass fiber or a thin net-like copper wire on the inside thereof, and the inside is decompressed to store cooling water such as water. When heat is obtained from the heating element at the low position, the cooling water is vaporized and moved to the high position, and the heating element is cooled by repeating a cycle of natural or forced cooling at the high position and liquefaction again to return to the low position.

  As another embodiment, the heat pipe 61 connected to the heat sink 110 with the fan can be selectively extended to the back surface 164 of the mother board 160 using the through hole 166. This embodiment is shown in FIG. The heat pipe 61 is connected to the side surface of the heat sink with fan 1100 in FIG. The heat pipe 61 extends from the front surface 162 of the motherboard 160 to the back surface 164 of the motherboard 160 through the through hole 166. In the dotted line portion of the heat pipe 61 in FIG. 8, a portion located below the air inlet 125 passes through the through hole 166 of the motherboard 160. In FIG. 8, the illustration of the mother board 160 is omitted. The heat pipe 61 is connected to a heat-generating electronic component or the like on the back surface 164 side at a position 62 in the figure, and moves the heat to the heat sink 1100 with a fan. Therefore, the heat transferred by the heat pipe 61 is radiated by the cooling fan 130. With this configuration, the intake from the back surface 164 of the through hole 166 and the arrangement of the heat pipe can be combined. The structure of the heat sink with fan 1100 in FIG. 8 is the same except that the heat sink with fan 110 in FIGS. 1, 3, and 4 and the heat pipe 61 are connected. Therefore, the illustration of the cooling fan 130 and the like is omitted in FIG. Here, since the heat sink with fan 1100 connects the heat pipe 61 using an attachment member, the heat pipe 61 can also be freely separated. As a result, it is possible to change the cooling performance by changing the material of the heat pipe 61 or the like. Further, the replacement of the elements 120 to 140 is not hindered.

  The cooling fan 130 forcibly cools the cooling fin 140 by generating an air flow by rotating. The cooling fan 130 includes a power unit 132 and a propeller unit 134 that is fixed to the power unit 132. The power unit 132 typically includes a rotating shaft, a bearing provided around the rotating shaft, a bearing house, and a magnet constituting a motor. The power unit 132 may have any structure known in the art. Since it can be used, detailed description is omitted here. But it is preferable that a heat insulation part is formed in the inner peripheral wall surface of a bearing house in order to prevent the electric heat to a bearing house. The heat insulating part is formed, for example, with a low heat transfer material such as fluorine resin or silicon resin on a thin film.

  The propeller section 134 has a desired number of rotor blades formed at a desired angle. The rotor blades are arranged conformally or non-equally and have the desired dimensions. The cooling fan 130 may be divided into the power unit 132 and the propeller unit 134 or may not be divided. The wiring connected to the cooling fan 130 is not shown. As described above, the cooling fan 130 can be sucked from both sides because the air inlets 125 are provided on both sides (122 and 124 side) of the housing 120.

The cooling fan 130 of the present embodiment is disposed on the same plane as the cooling fin 140 described below, and is itself formed thin. For this reason, the base 220 can be maintained in a low profile when stored in a notebook PC 200 described later. The heat sink 110 with the fan having the cooling fan 130 is arranged in parallel to one surface (surface 162) of the mother board 160. Such a structure also contributes to a reduction in the thickness of the base 220 of the notebook PC 200 described later. As described above, the through hole 166 of the mother board 160 is selectively positioned below the cooling fan 130.

  As shown in FIG. 4, the cooling fin 140 includes a number of aligned plate-like fins 142 and a base portion 144 that constitutes a part of the housing 120. Since the cooling fin 140 has a convex shape and increases the surface area, the heat dissipation effect is increased. However, the shape of the fin 142 is not limited to a plate shape, and an arbitrary arrangement shape such as a pin shape or a curved shape can be adopted. In addition, the fins 142 do not need to be aligned horizontally at regular intervals, and may be arranged in a radial manner or inclined with respect to the base portion 144 or the lower surface 124. Further, the fin 142 may be disposed around the cooling fan 130. The number of fins 142 can also be set arbitrarily. The fin 142 is preferably formed of a high thermal conductivity material such as aluminum, copper, aluminum nitride, artificial diamond, or plastic. The fin 142 is formed by mold forming, press fitting, brazing, welding, injection molding, or the like.

  The base portion 144 constitutes a part of the housing 120 as shown in FIG. 4 and functions as a heat receiving surface of the CPU 150 described later. For this reason, the base 144 needs to be in close contact with the CPU 150 to improve heat conduction. A large number of fins 142 are connected to the back surface of the heat receiving surface of the base portion 144. The base 144 is preferably formed of a high thermal conductivity material such as aluminum, copper, aluminum nitride, artificial diamond, or plastic. Further, the base portion 144 may be formed alone, or may be formed in an integrated state with the fins 142. If the fin 142 and the base portion 144 are integrated and molded, the thermal resistance is reduced, so that the thermal conductivity can be improved.

  The base 144 is formed by mold forming, press fitting, brazing, welding, injection molding, or the like. In the present embodiment, the housing 120 has a hole 146 formed in a portion where the base 144 is fitted, and the base 144 constitutes a part of the housing 120. However, the base 144 may not be part of the housing 120 and may be connected to the housing lower surface 124.

  Hereinafter, a method for manufacturing the cooling fin 140 will be described. As a manufacturing method of the cooling fin 140, a method of processing a metal material is generally used, and types thereof include a forging method and a pressing method. The forging method and the pressing method can form the fin 142 and the base portion 144 as an integral mold. The forging method is a method of forming irregularities by applying pressure to a heated metal lump. For example, the cooling fin 140 shown in FIG. 4 is formed by forming a mold having desired unevenness and pressurizing a metal lump with the mold. Since the forging method does not punch or melt the metal, the forging line has a shape along the mold, so that it can be formed without losing strength.

On the other hand, the pressing method will be described with reference to FIGS. Here, FIG. 5 is a schematic diagram for explaining the steps of the pressing method. FIG. 6 is a cross-sectional view of the cooling fin 140 formed by the method of FIG. According to FIG. 5, the cooling fin 140 is manufactured from a plate-like metal plate M. In the pressing method, for example, a press progressive die having a square pressure member A is used. First, as shown in FIG. 5, the plate-shaped metal plate M is pressed (pressed) by a square-shaped pressure member A, and a recess is formed. The press progressive die presses the pressing member A in a progressive manner to successively form recesses in the metal plate M. Thereby, as shown in FIG. 6, a desired number of concave portions are formed in the metal plate M, and fins 142 are formed as convex portions corresponding to the concave portions.

  The CPU 150 is disposed directly below the portion of the storage unit 128 where the cooling fins 140 are placed. In other words, the cooling fin 140 is formed in the storage portion 128 of the portion surrounded by the mounting hole 123a and the mounting groove 123b. As described above, the cooling fin 140 (the base 144 thereof) and the CPU 150 are thermally connected. As a result, the heat from the CPU 150 is efficiently transferred to the cooling fin 140. Further, the cooling fin 140 can receive heat from the cooling fan 130 and efficiently radiate heat.

Since the cooling fin 140 is a heat exchanging part, better thermal conductivity is required than other elements constituting the heat sink 110 with fan. In particular, in order to improve the cooling effect, it is most efficient to change the shape, size, material and the like of the cooling fin 140. Further, the cooling fin 140 is a member that is relatively easy to replace because it does not require electrical connection unlike the cooling fan 130. Therefore, the heat sink with fan 110 according to the present invention allows the cooling fin 140 to be replaced alone by dividing the casing 120 and the cooling fin 140 that are conventionally formed integrally.

Cooling fins 140 of the present embodiment, the fins 142 on the base portion 144 are integrally formed. The cooling fin 140 is connected to the housing 120 by an adhesive, for example. As the adhesive, an adhesive having high thermal conductivity is used. Further, the cooling fin 140 may be connected so as to be sandwiched between the lower surface 124 of the housing 120 and the CPU 150 for convenience of replacement. In this case, the base portion 144 of the cooling fin 140 is formed with a larger area than the hole 146 provided in the housing 120. In such an attachment method, it is not necessary to newly provide an attachment member for the cooling fin 140, so that the attachment process can be simplified.

The heat sink 110 with a fan according to the present invention has a structure in which the casing 120, the cooling fan 130, and the cooling fins 140 are independent and separated from each other. Therefore, the desired cooling performance can be controlled by the combination thereof. Therefore, the heat sink 110 with a fan can respond finely to installation elements of various shapes and heat generation amounts and installation locations of various shapes and dimensions at the time of installation. Therefore, it is not necessary to design a different heat sink for each electronic device, and it is possible to prevent an increase in the cost of the electronic device.

Here, the cooling fan can also be removed from the conventional heat sink with a fan. However, when it is desired to use a larger cooling fan in order to increase the cooling efficiency, it has been extremely difficult to replace the cooling fan depending on the structure of the mounting member to the casing and the size of the propeller portion. Therefore, conventionally, the cooling fan has not been replaced, and the entire heat sink has been replaced. In addition, when the cooling fan is damaged, the entire heat sink must be replaced, which is uneconomical. However, when replacing the cooling fan 130, the heat sink 110 with a fan according to the present invention can select the casing 120 having a shape suitable for the cooling fan 130. It is more economical than doing it. In addition, since the heat sink with fan 110 can optimize the cooling performance in consideration of the compatibility of the components 120 to 140, higher performance cooling is possible.

Moreover, the heat sink 110 with a fan of this invention can reduce a weight by changing the material of the elements 120 to 140, etc. FIG. For example, if the shape of the cooling fin 140 is maintained and the material is changed from copper (Cu) to aluminum (Al), the weight becomes 1/3 or less. Thus, if the weight of the heat sink 110 with a fan is reduced, the weight of a notebook PC 200 having such a heat sink 110 with a fan will be reduced.

  Furthermore, the present invention is not limited to the heat sink 110 with a fan, and may be a heat sink 110 a including a housing 120 and cooling fins 140. For example, when it is desired to reduce the weight of the heat sink 110a, it is effective to change the material of the heat sink 110a from copper (Cu) to aluminum (Al) as described above. However, aluminum has a lower thermal conductivity than copper, and heat exchange performance may be reduced. Therefore, the cooling fins 140 are made of copper as they are, and while maintaining high heat exchange properties, the casing is replaced with aluminum to reduce the weight. This makes it possible to reduce the weight without degrading the cooling performance.

A method for manufacturing the heat sink with fan 110 will be briefly described. First, the housing 120 is formed by, for example, an aluminum die casting method. Thereafter, the cooling fan 130 formed by another process is attached to the housing 120. At this time, a lead wire lead hole (not shown) is formed in the casing 120, and the cooling fan 130 and the lead wire of the motherboard are connected through the lead hole. Thereby, the cooling fan is electrically connected to the motherboard 160. Next, the cooling fin 140 is fitted into the housing 120 using an adhesive or the like, for example, and the heat sink 110 with a fan is manufactured. After manufacturing, the heat sink with fan 110 can be replaced with each other to reduce the weight, for example, due to a damaged element in order to improve cooling performance.

  In the development stage, the heat sink 110 with a fan formed by the above manufacturing method manufactures each of the elements 120 to 140 individually, and corresponds to the size and shape of the heating element, the size and shape of the installation location, etc. by the combination thereof. The degree of freedom in design can be increased. Further, since the development regarding each of the elements 120 to 140 can be performed individually, the development speed can be improved.

  The heat sink with fan 110 of this embodiment generally has a higher heat dissipation efficiency than the structure in which the cooling fan 130 is disposed above the cooling fins 140. This is because (1) if the cooling fan is on the upper part of the cooling fin, the amount of air blown from the propeller part is reduced in the part of the cooling fin immediately below the power part, and effective cooling cannot be performed. ) The heat source of the CPU is concentrated in the central part.

  Further, such a structure is useful for a low-profile notebook PC because the heat sink with fan 110 itself is thin. Further, this structure facilitates communication between the through hole 166 of the selectively provided motherboard 160 and the cooling fan 130. However, as long as the communication between the cooling fan 130 and the through hole 166 of the motherboard 160 is ensured, it will be understood that the cooling fan 130 and the cooling fin 140 do not need to be arranged on the same plane.

  Alternatively, the cooling fin 140 and the upper surface 122 may be thermally conducted by interposing a heat conducting elastic body (for example, silicon rubber) between them to enhance the heat dissipation effect. Such a structure also contributes to the vibration of the cooling fin 140 accompanying the rotation of the cooling fan 130 and the removal of noise accompanying the vibration. Since the heat conducting elastic body absorbs vibration accompanying rotation of the cooling fan 130, loosening of the screws 170 can be prevented.

  The motherboard 160 is a printed circuit board on which circuit elements such as a CPU socket 151, various memories (sockets), a chip set, an expansion slot, and a BIOSROM are mounted, and has a front surface 162, a back surface 164, and through holes 166 that penetrate both surfaces 162 and 164. Have. Here, the installation of the through-hole 166 is arbitrary, and is provided in order to cool the both surfaces 162 and 164 of the mother board 160 more effectively. In FIG. 1 and FIG. 2, various other circuit elements mounted on the motherboard 160 are omitted.

  In the vicinity of the CPU socket 151, a memory (such as SRAM) not shown and a CPU chip set are arranged. The CPU chip set has a function of connecting the CPU 150 and the memory to each other and controlling the data flow therebetween, and is typically disposed between the CPU 150 and the memory. Both the memory and the CPU chip set are heating elements. The through hole 166 is provided so as not to disturb the arrangement of the memory and the CPU chip set.

The through hole 166 has a diameter of at least about 8 mm or more, preferably about 10 mm or more for ventilation of the back surface 164. “About 8 mm” means that screw holes and inspection holes typically provided on the mother board 160 are not included. This is because these screw holes and the like are too small for ventilation of the back surface 164. In the present embodiment, the shape of the through-hole 166 is circular. However, the shape is not limited to this, and the through-hole 166 can have an arbitrary shape such as an ellipse or a polygon. In other words, the through-hole 166 has an area of at least about 16πmm ² or more, preferably about 25πmm ² or more. The through hole 166 needs to communicate with the cooling fan 130. “Communication” means that the cooling fan 130 can ventilate the back surface 164 through the through hole 166.

One through hole 166 may have the above-mentioned area, but it is sufficient if the through-hole 166 is divided into a plurality of holes and the total area of these holes satisfies the above-mentioned area requirement. In this case, it is preferable that the plurality of holes are arranged close to each other. The degree of proximity is sufficient to ensure communication between each hole and the cooling fan 130. For example, the through hole 166 may be a mesh hole provided in the mother board 160 . Moreover, the shape and size of each hole may be the same or different.

The operation of the heat dissipation mechanism 100 will be described in the operation of the notebook PC 200 to which the heat dissipation mechanism 100 described below is applicable with reference to FIG. Here, FIG. 7 is a schematic perspective view of the notebook PC 200 of the present invention. As shown in FIG. 7, the notebook computer 200 includes a liquid crystal display (LCD) bezel frame 210 and a base 220 connected by a hinge 202. An LCD screen 212 is disposed on the LCD bezel frame 210. Typically, the base 220 is made of a plastic material and has a thickness of about 50 mm or less, and preferably has a thickness of about 20-30 mm. The heat dissipating mechanism 100 of the present invention uses a heat sink 110 with a fan, and the heat sink 110 with a fan does not dispose the cooling fan 130 on the cooling fin 140 but on the same plane. Can be maintained. The LCD bezel frame 210 has a substantially rectangular shape that holds the LCD screen 212.

  The base 220 includes a keyboard section 222 for information types, but the keyboard type and keyboard layout are not limited. The keyboard type is 101, 106, 109, ergonomic, etc. The keyboard layout is QWERTY layout, DVORAK layout, JIS layout, new JIS layout, Japanese input consortium reference layout (NICOLA: Nihongo Nyryoku Consortium Layout), etc. Absent.

  The base 220 also includes a pointing device 224 that emulates part of the mouse function. Regardless of the structure shown in FIG. 7, the pointing device 224 includes a mouse, a trackball, a trackpad, a tablet, a digitizer, a joystick, a joypad, a touch panel, a stylus pen, and the like.

  Further, the base 220 has a heat dissipating sheet metal and / or an exhaust port (not shown) inside the side portion 225. The heat radiating sheet metal and / or the exhaust port communicates with the exhaust port 127. That is, the lower surface 124 in the vicinity of the exhaust port 127 is connected to the heat radiating sheet metal, the air discharged from the exhaust port 127 is blown to the heat radiating sheet metal, or can be discharged to the outside from the exhaust port of the side portion 225. Yes. When connected to the heat radiating sheet metal, the temperature of the fan-mounted heat sink 110 is constantly kept substantially constant (for example, at room temperature).

In operation, the user of the notebook PC 200 operates the keyboard section 222 or the pointing device 224 to execute a program stored in a hard disk (not shown) stored in the base 220. At this time, the CPU 150 downloads necessary data from a hard disk and a ROM (not shown) to a memory (not shown). At this time, heat generated from the CPU 150 is transferred to the cooling fins 140 through the case 120 of the heat sink 110 with fan and the lower surface 124 of the case 120 that are thermally coupled. As a result, the heat is naturally cooled from the surfaces of the cooling fins 140 and the housing 120. Further, the air blowing from the cooling fan 130 forcibly cools the cooling fins 140.

  Warm air from the memory, CPU chip set, and other heating elements mounted on the surface 162 of the motherboard 160 is introduced into the housing 120 from the air inlet 125 by the cooling fan 130 without passing through the through hole 166. The introduced warm air is exhausted from the storage portion (wind tunnel space) 128 to the exhaust port 127 by the cooling fan 130. The warm air is cooled by heat exchange with the cooling fins 140 and the housing 120 while passing through the storage portion 128. As described above, the cooling fin 140 receives forced cooling by the cooling fan 130. Further, the air discharged from the exhaust port 127 is blown onto the heat radiating sheet metal and further cooled, or is discharged to the outside from the exhaust port provided in the side portion 225.

  Warm air from the heating element mounted on the back surface 164 of the motherboard 160 is introduced into the housing 120 from the air inlet 125 via the through hole 166 by the cooling fan 130. The introduced warm air is exhausted from the storage portion (wind tunnel space) 128 to the exhaust port 127 by the cooling fan 130. The warm air is cooled by heat exchange with the cooling fins 140 and the housing 120 while passing through the storage portion 128. As described above, the cooling fin 140 receives forced cooling by the cooling fan 130. Further, the air discharged from the exhaust port 127 is blown onto the heat radiating sheet metal and further cooled, or is discharged to the outside from the exhaust port provided in the side portion 225.

  As a result, the CPU 150 and other circuit elements are thermally protected regardless of whether they are on the front surface 162 or the back surface 164 of the motherboard 160. In addition, the fan-mounted heat sink 110 can be finely adapted to circuit elements having various shapes and calorific values and installation locations of various shapes and dimensions, and has an optimum cooling performance. To protect. Accordingly, the circuit element of the notebook PC 200 can perform a desired process without being subjected to thermal destruction, thermal degradation, and malfunction. Further, the base 220 made of a plastic material does not cause thermal deformation or low temperature burn due to heat generation.

  Moreover, although the form of a present Example demonstrated as an example the case where the heat sink 110 with a fan inhales from upper and lower surfaces of the motherboard 160, and exhausts from the exhaust port 127, the flow of air may be reverse. In this case, the heat sink 110 with a fan exhausts both the upper and lower surfaces of the motherboard 160 using the exhaust port 127 as an intake port.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the gist. For example, an electronic device to which the heat dissipation mechanism of the present invention can be applied is not limited to a notebook personal computer, but a desktop PC, a word processor, a personal digital assistant (PDA), and other portable electronic devices (a portable game device, various drives). Etc.) can be widely applied.

It is a disassembled perspective view of the thermal radiation mechanism as an exemplary aspect of this invention. It is the perspective view which looked at the motherboard of the thermal radiation mechanism shown in FIG. 1 from the back surface. It is a general | schematic expansion perspective view of the heat sink with a fan of the thermal radiation mechanism shown in FIG. It is a perspective view which shows the inside of the heat sink with a fan shown in FIG. It is a schematic diagram for demonstrating the process of a press method. It is sectional drawing of the cooling fin shape | molded by the method of FIG. FIG. 2 is a schematic perspective view of a notebook personal computer to which the heat dissipation mechanism shown in FIG. 1 can be applied. It is a schematic perspective view of the heat sink with a fan as another exemplary aspect of this invention.

Explanation of symbols

100 Heat Dissipation Mechanism 110 Heat Sink with Fan 120 Case 125 Intake Port 127 Exhaust Port 128 Storage Unit 130 Cooling Fan 140 Cooling Fin 142 Fin 144 Base 150 CPU
160 Motherboard 166 Through-hole 200 Notebook personal computer 210 LCD bezel frame 220 Base

Claims (22)

A heat sink for dissipating the heat generating part mounted on the printed circuit board,
A housing provided on the side of the printed circuit board on which the heat generating unit is mounted;
A cooling fin that is provided on a side of the printed circuit board on which the heat generating unit is mounted, is detachably coupled to the housing, receives heat from the heat generating unit, and dissipates the heat generating unit;
Provided on a side of the heating unit is mounted in the printed circuit board, it has a cooling fan connected to the housing while forcibly cooling the cooling fins,
The casing is made of a first material, the cooling fin is made of a second material different from the first material, and the second material has a higher thermal conductivity than the first material. A heat sink characterized in that the heat sink is lower in weight when the casing is made of the first material than when the casing is made of the second material . A heat sink for dissipating the heat generating part mounted on the printed circuit board,
A housing provided with the heat generating portion of the printed circuit board and having a hole formed therein ;
A heat receiving surface provided on a side of the printed circuit board on which the heat generating portion is mounted, and is fitted into the hole so as to be separable from the housing and coupled to the housing; the heat receiving surface receives heat from the heat generating portion; A base portion having cooling fins that are formed on the back surface side of the substrate and dissipate heat from the heat generating portion;
Provided on a side of the heating unit is mounted in the printed circuit board, it has a cooling fan connected to the housing while forcibly cooling the cooling fins,
The casing is made of a first material, the cooling fin is made of a second material different from the first material, and the second material has a higher thermal conductivity than the first material. A heat sink characterized in that the heat sink is lower in weight when the casing is made of the first material than when the casing is made of the second material .   The heat sink according to claim 1 or 2, wherein the cooling fan and the cooling fin are arranged on the same plane.   The heat sink according to claim 1 or 2, wherein the casing has an air inlet at a mounting position of the cooling fan on a surface mounted on the printed circuit board.   The heat sink according to claim 1, wherein the casing includes a storage unit that stores the cooling fan in a separable manner. The storage section is
A semicircular section having a semicircular cross section for housing the cooling fan;
A rectangular parallelepiped section that is connected to the semicircular portion and houses the cooling fins,
The heat sink according to claim 5, further comprising an exhaust port connected to the rectangular part and exhausting an air flow generated by the cooling fan. A printed circuit board on which the heat generating part is mounted;
An electronic device having a heat sink provided on the printed circuit board for cooling the heat generating part,
The heat sink is
A housing provided on the side of the printed circuit board on which the heat generating unit is mounted;
A cooling fin that is provided on a side of the printed circuit board on which the heat generating unit is mounted, is detachably coupled to the housing, receives heat from the heat generating unit, and dissipates the heat generating unit;
Provided on a side of the heating unit is mounted in the printed circuit board, it has a cooling fan connected to the housing while forcibly cooling the cooling fins,
The casing is made of a first material, the cooling fin is made of a second material different from the first material, and the second material has a higher thermal conductivity than the first material. An electronic device characterized in that the weight is smaller when the casing is made of the first material than when the casing is made of the second material . A printed circuit board on which the heat generating part is mounted;
An electronic device having a heat sink provided on the printed circuit board for cooling the heat generating part,
The heat sink is
A housing provided with the heat generating portion of the printed circuit board and having a hole formed therein ;
A heat receiving surface provided on a side of the printed circuit board on which the heat generating portion is mounted, and is fitted into the hole so as to be separable from the housing and coupled to the housing; the heat receiving surface receives heat from the heat generating portion; A base portion having cooling fins that are formed on the back surface side of the substrate and dissipate heat from the heat generating portion;
Provided on a side of the heating unit is mounted in the printed circuit board, it has a cooling fan connected to the housing while forcibly cooling the cooling fins,
The casing is made of a first material, the cooling fin is made of a second material different from the first material, and the second material has a higher thermal conductivity than the first material. An electronic device characterized in that the weight is smaller when the casing is made of the first material than when the casing is made of the second material . The cooling fan and the cooling fins claim 7 or 8 electronic device according to being disposed on the same plane. Wherein the housing, according to claim 7 or 8 electronic device according and having an inlet to the mounting position of the cooling fan of the surface to be mounted on the printed circuit board. Wherein the housing, the electronic device according to claim 7 or 8, characterized in that it has a housing part for detachably housing the cooling fan. The storage section is
A semicircular section having a semicircular cross section for housing the cooling fan;
A rectangular parallelepiped section that is connected to the semicircular portion and houses the cooling fins,
The electronic apparatus according to claim 11 , further comprising: an exhaust port that is connected to the rectangular part and exhausts an air flow generated by the cooling fan. The electronic device according to claim 10 , wherein the printed circuit board has a through hole that communicates with the air inlet of the housing. The electronic device according to claim 10 , wherein the printed board has a heat generating portion mounted on the printed board opposite to the side on which the heat sink is mounted. A heat dissipating mechanism comprising a printed circuit board on which a heat generating part is mounted and a heat sink provided on the printed circuit board for cooling the heat generating part,
The heat sink is
A housing provided on the side of the printed circuit board on which the heat generating unit is mounted;
A cooling fin that is provided on a side of the printed circuit board on which the heat generating unit is mounted, is detachably coupled to the housing, receives heat from the heat generating unit, and dissipates the heat generating unit;
Provided on a side of the heating unit is mounted in the printed circuit board, it has a cooling fan connected to the housing while forcibly cooling the cooling fins,
The casing is made of a first material, the cooling fin is made of a second material different from the first material, and the second material has a higher thermal conductivity than the first material. The heat dissipation mechanism is characterized in that the weight is lower when the casing is made of the first material than when the casing is made of the second material . A heat dissipating mechanism comprising a printed circuit board on which a heat generating part is mounted and a heat sink provided on the printed circuit board for cooling the heat generating part,
The heat sink is
A housing provided with the heat generating portion of the printed circuit board and having a hole formed therein ;
A heat receiving surface provided on a side of the printed circuit board on which the heat generating portion is mounted, and is fitted into the hole so as to be separable from the housing and coupled to the housing; the heat receiving surface receives heat from the heat generating portion; A base portion having cooling fins that are formed on the back surface side of the substrate and dissipate heat from the heat generating portion;
Provided on a side of the heating unit is mounted in the printed circuit board, it has a cooling fan connected to the housing while forcibly cooling the cooling fins,
The casing is made of a first material, the cooling fin is made of a second material different from the first material, and the second material has a higher thermal conductivity than the first material. The heat dissipation mechanism is characterized in that the weight is lower when the casing is made of the first material than when the casing is made of the second material . The heat dissipation mechanism according to claim 15 or 16, wherein the cooling fan and the cooling fin are arranged on the same plane. The heat radiating mechanism according to claim 15 or 16 , wherein the casing has an air inlet at a mounting position of the cooling fan on a surface mounted on the printed circuit board. The heat radiating mechanism according to claim 15 or 16 , wherein the casing includes a storage unit that stores the cooling fan in a separable manner. The storage section is
A semicircular section having a semicircular cross section for housing the cooling fan;
A rectangular parallelepiped section that is connected to the semicircular portion and houses the cooling fins,
The heat dissipation mechanism according to claim 19 , further comprising: an exhaust port connected to the rectangular part and exhausting an air flow generated by the cooling fan. The heat dissipation mechanism according to claim 18 , wherein the printed circuit board has a through hole communicating with the air inlet of the housing. The heat dissipation mechanism according to claim 18 , wherein the printed circuit board has a heat generating portion mounted on the printed circuit board opposite to the surface on which the heat sink is mounted.