JP4645420B2 - Heat receiver and cooling device provided with the same - Google Patents

Description

  The present invention uses a heat-generating electronic component such as a semiconductor element that generates heat such as a microprocessing unit (hereinafter referred to as MPU) used in a personal computer or the like, or an electronic component having other heat-generating parts, for cooling by circulation of a liquid refrigerant. The present invention relates to a heat receiver and a cooling device including the heat receiver.

  The speed of data processing in recent electronic devices such as computers is very rapid, and the clock frequency of heat-generating electronic components such as MPU has become much larger than before, so the amount of heat generated Has increased. For this reason, each heat generating electronic component exceeds the operating temperature range, and as a result, malfunctions and thermal destruction of the electronic components often occur.

  Therefore, keeping each heat generating electronic component mounted in the electronic device within the operating temperature range causes the heat generating electronic component to operate normally, and as a result, the electronic device can be stably operated. It has become an important issue to do so.

  As a conventional heat dissipation method for heat-generating electronic components, not only a heat sink composed of a plurality of heat-dissipating fins is brought into direct contact with the heat-generating electronic components for natural heat dissipation, but also a method in which the heat sink is blown and cooled by a fan device, In a heat sink module thermally connected to the heat radiating part using a heat pipe, the heat radiating part is forcibly blown and cooled by fan air blowing, or liquid refrigerant is forced to circulate by a pump and heat is transferred from the heat receiving part to the heat radiating part. Cooling devices using a liquid cooling system that has been transported have become indispensable, and in the future, in addition to improvements in the cooling capacity of these cooling devices, it is also necessary to reduce the size and weight.

  Therefore, as described in (Patent Document 1), for example, as described in (Patent Document 1), as a heat receiver corresponding to miniaturization and high integration of a semiconductor element, it is possible to realize compactness while reducing pressure loss in the flow path of the liquid refrigerant. A heat receiver has been proposed.

  10 (a) is an exploded perspective view of the heat receiver described in (Patent Document 1), FIG. 10 (b) is an external perspective view thereof, and FIG. 10 (c) is a partially enlarged sectional view of the AA cross section. By forming a plurality of grooves 102 on one main surface 101a of a rectangular substrate 101 having a side of about 15 mm by a known method such as chemical etching, for example, the width is set to about 50 μm and the depth is set to about 300 μm. The grooves 102 are formed substantially in parallel at substantially equal pitches. Here, the peripheral portion of the substrate 101 is left, and the top surface of the fin 107 is lower than the peripheral portion as shown in FIG. 10C, for example.

  A cover plate 103 is attached to one main surface 101 a of the substrate 101 so as to cover the entire surface, and through holes 104 and 105 are formed in the cover plate 103. A connection cover (not shown) is attached to these through holes 104 and 105, and connected to different refrigerant flow paths (not shown) as a refrigerant supply port and a refrigerant discharge port, respectively.

  Then, the refrigerant supplied from the refrigerant supply source (not shown) to the one refrigerant flow path is sent to the one through hole 104 from the one refrigerant flow path, and the region between the substrate 101 and the cover plate 103 is passed through. Then, it is sent out from the other through hole 105 to another refrigerant flow path. As a result, the liquid refrigerant flows smoothly in the flow path of the liquid refrigerant provided in the heat receiver 100, and a sufficient cooling effect is exhibited. There is no concern that the semiconductor element 106 to be cooled provided on 101b is cooled and destroyed, and the reliability is improved.

  On the other hand, as a heat receiving structure of another cooling device for cooling one or more semiconductor elements mounted on a circuit board, for example, a thermally conductive gas is enclosed as in (Patent Document 2). A heat receiving structure provided with an open space has also been proposed.

  11A is a cross-sectional view of the cooling device described in (Patent Document 2), and FIG. 11B is a partially enlarged cross-sectional view of the cooling device 110. The cooling device 110 includes a plurality of semiconductors mounted on the circuit board 111. A cap 113 covering the circuit board 111 so as to surround the element 112, and a space 114 formed between the cap 113 and the circuit board 111 and filled with a heat conductive gas is disposed to face the semiconductor element 112. The thermal bridge element 115 and the water cooling jacket 116 attached to the upper surface of the cap 113 are included.

  Here, the thermal bridge element 115 includes a first fin 117 and a second fin 118, and the fins 117 and 118 are provided on the base portions 119 and 120 and the base portions 119 and 120, respectively. It is composed of a plurality of comb-shaped fin portions 121 and 122 formed integrally.

  The fin portions 121 and 122 are alternately fitted, and the fitting portions of the fin portions 121 and 122 are fitted with a minute gap that is precisely controlled.

  A compression spring 125, which is an example of an elastic member having an action point on the base portions 119, 120, is accommodated in the recesses 123, 124 formed in the intermediate portions of the first and second fins 117, 118. The contact surface 119a of the base portion 119 of the first fin 117 is brought into contact with the cap 113 and the contact surface 120a of the base portion 120 of the second fin 118 is brought into contact with the semiconductor element 112 with an appropriate contact pressure. Is being energized.

  The heat generated in the semiconductor element 112 is transmitted to the base portion 120 of the second fin 118 via the extremely thin heat conductive gas layer 126, and after the base portion 120 is expanded in the lateral direction, the heat transfer area is expanded. , To the fin portion 122, to the fin portion 121 of the first fin 117 and the base portion 119 through the gas layer 126, to the cap 113 through the gas layer 126, and finally to the water cooling jacket 116. It is removed by the liquid refrigerant flowing in the interior.

  The contact surfaces 119a and 120a of the base portions 119 and 120 and the contact surface 113a of the cap 113 with the base portion 119 are finished to be extremely smooth, and the contact thermal resistance is suppressed to a sufficiently small value. Is expensive.

  In addition, since the fitting portions of the fin portions 121 and 122 are fitted with a minute interval precisely controlled by a compression spring, the second fin 118 tilts following the slight tilt of the semiconductor element 112. However, the movement of the first fin 117 is not restricted.

Accordingly, the base portion 120 of the second fin 118 is always kept in a good plane contact state with the back surface of the semiconductor element 112, and the heat transfer efficiency is increased. Further, even when the semiconductor element 112 is inclined, the first and second fins 117 and 118 are not in contact with each other, and a stable thermal resistance value is obtained.
JP-A-6-326226 (Page 6, FIGS. 1 (a), (b), FIG. 2 (a)) JP 61-231744 (5th page, FIG. 1)

  However, in the heat receiver 100 of the above-described (Patent Document 1), it is relatively easy to make the heat receiver 100 small, thin, and compact, but the fins 107 are simply substantially parallel at substantially equal pitches. Therefore, the liquid refrigerant flowing through the flow path between the substrate 101 and the cover plate 103 is expected to be the hottest until it is fed from one through hole 104 and sent from the other through hole 105. In the central region of the substrate 101, which is a contact region with the semiconductor element 106, the liquid refrigerant becomes a laminar flow region in which the liquid refrigerant flows substantially in parallel with the fins 107. However, there is a problem that sufficient cooling performance cannot be obtained in the case of dealing with a heating element having a large calorific value.

  On the other hand, it is necessary to further reduce the size of the heat receiver 100 with the reduction in thickness and weight of an electronic device on which the cooling device including the heat receiver 100 is mounted, and it flows in a limited space in the heat receiver. Since the flow path of the liquid refrigerant is reduced in contrast to the narrowing of the pitch of the plate-like fins 107 in order to increase the contact area between the liquid refrigerant and the fins 107, the pressure loss increases accordingly, and the circulating liquid There was also a problem that the cooling performance was lowered due to a decrease in the flow rate of the refrigerant.

  Further, in order to increase the heat radiation area at the fin 107, a known technique such as chemical etching is used to form the groove 102 having a fine width on the substrate 101. A resist forming process for forming a photosensitive resist on the surface of the metal material, an exposure (baking) process using a photomask, and a developing process for removing other resists leaving only the resist corresponding to the portion where the fin is formed, When the substrate 101 is made of copper or a copper alloy metal material, there are a number of processes including an etching process in which a solution of ferric chloride is sprayed, and finally a resist removing process. There was also a problem that it was extremely inferior in mass productivity as compared with molding.

  Furthermore, in the heat receiving structure of the cooling device 110 of (Patent Document 2), not only the structure is complicated, but also the heat transfer path from the semiconductor element 112 to the liquid refrigerant flowing inside the water cooling jacket 116 is relatively long, and the circuit There are several gas layers having a very large thermal resistance in the cap 113 covering the substrate 111, and even a gas having a higher thermal conductivity than air, such as hydrogen or helium, is thermoelectric such as copper or aluminum. Compared with a good metal material, its thermal conductivity is extremely small, and furthermore, since there is a thermal resistance of each of the cap 113 and the water cooling jacket 116 and a boundary layer, there is a thermal resistance of all of them. As a result, the thermal resistance as a whole becomes very large, and sufficient cooling performance is obtained especially when dealing with heating elements that generate large amounts of heat. There is a problem that is not.

  The present invention solves such a conventional problem, improves the structure of the heat receiver, promotes heat exchange with the liquid refrigerant, can easily improve the cooling performance even with a small liquid refrigerant flow rate, In addition, it is an object of the present invention to provide a heat receiver that has a simple structure and can easily cope with downsizing.

  In order to achieve the above object, a heat receiver according to the present invention is a heat receiver that connects a pair of liquid transport paths and allows liquid refrigerant to flow therein, and has one surface that is thermally connected to a heating element. Between the heat receiving plate and the casing, a heat receiving plate in which the first fin for heat transfer is erected on the back surface, a casing combined with the heat receiving plate so as to accommodate the first fin, and A heat transfer chamber formed between the casing and the heat receiving plate, and a pump chamber for accommodating the impeller between the casing and the partition wall member having a through hole in the center. The heat of the first fin is transferred to the liquid refrigerant that has flowed into the pump, and the impeller contained in the pump chamber is transferred to the liquid refrigerant that has passed through the through hole of the partition wall member from the heat transfer chamber and flowed into the pump chamber. Propulsive force is applied by the rotational movement of the partition plate, and the heat receiving plate Erected a second fin to direction, it is mainly characterized in that to control the flow of liquid coolant.

  According to the heat receiver of the present invention, the heat exchange with the liquid refrigerant can be promoted, the cooling performance can be easily improved even with a small liquid refrigerant flow rate, and the size reduction can be easily achieved with a simple structure. Play.

  According to the first aspect of the present invention, there is provided a heat receiver that connects a pair of liquid transport paths and allows a liquid refrigerant to flow inside, wherein a heat receiving surface that is thermally connected to a heating element is provided on one surface thereof. A heat receiving plate having the first fin for heat transfer standing on the back surface, a casing combined with the heat receiving plate so as to accommodate the first fin, and the heat receiving plate and the casing are sandwiched between the heat receiving plate and the casing. A heat transfer chamber is formed between the heat receiving plate and a pump chamber that houses the impeller between the heat receiving plate and a partition member having a through hole in the center, and flows into the heat transfer chamber The heat of the first fin is transmitted to the liquid refrigerant, and the rotational movement of the impeller accommodated in the pump chamber is transferred to the liquid refrigerant that has passed through the through hole of the partition wall member from the heat transfer chamber and flowed into the pump chamber. The liquid refrigerant is applied from the surface of the partition wall member facing the heat receiving plate toward the heat receiving plate. Since the second fin for controlling the flow is erected, first, a plurality of heat transfer firsts having a function of transferring heat to the liquid refrigerant on the back surface of the heat receiving surface where the heating element is thermally connected and the temperature is highest. Since the one fin is erected, the heat conduction path from the heating element to the first fin is shortened and the thermal resistance is reduced, and the heat of the heating element is more efficiently transferred in the heat transfer chamber. Heat can be transferred to the liquid refrigerant flowing through the flow path between the fins.

  And since the 2nd fin which controls the flow of a liquid refrigerant is standingly arranged from the surface facing a heat receiving plate of a partition member to the direction of a heat receiving plate, the 2nd fin is the 1st fin for heat transfer The flow direction of the liquid refrigerant flowing through the gap in the gap is controlled, heat exchange with the liquid refrigerant is promoted, and the cooling performance can be easily improved even with a small liquid refrigerant flow rate. Can be easily handled.

  In addition, when trying to erect the first fin on the heat receiving plate by die casting with relatively high productivity using aluminum alloy, copper alloy, zinc alloy, etc., the durability of the mold for molding, In order to obtain stable quality moldability without cracks, the thickness of the first fin and the gap between the first fins adjacent to each other should be at least about 0.8 to 1.0 mm. In order to increase the contact area with the liquid refrigerant, further narrowing the pitch requires another method that is complicated in manufacturing method such as chemical etching and inferior in mass productivity.

  However, a heat transfer effect equivalent to substantially increasing the contact area with the liquid refrigerant by using the heat receiver having a simple structure in which the second fin for appropriately controlling the flow of the liquid refrigerant is combined. Therefore, mass production of the heat receiver is improved, and inexpensive manufacturing is possible.

  Further, since the pump chamber is provided in the heat receiver and has a pump function for circulating the liquid refrigerant, the cooling device provided with the heat receiver does not require a separate pump in the liquid circulation path. In addition, the size of the entire cooling device can be further reduced.

  According to the second aspect of the present invention, the first fin has a plate-like outer shape along the flow direction of the liquid refrigerant, and the second fin has a plate-like outer shape along the flow direction of the liquid refrigerant. The plurality of first fins are arranged in a direction orthogonal to the flow direction of the liquid refrigerant, and the second fins are inserted into the gaps between the first fins adjacent to each other. The second fin is interposed in the flow path of the gap between the first fins for heat, and the liquid refrigerant is controlled so as to continuously flow to a region close to the surface of the first fin for heat transfer. A heat transfer effect equivalent to that when the refrigerant contacts the surface of the first fin more efficiently and substantially increases the contact area per unit flow rate with the liquid refrigerant can be obtained. Cooling performance can be improved and it is easy to cope with downsizing.

According to invention of Claim 3 of this invention, it is set as the external shape which has a level | step difference which makes a 1st fin gradually thin as it leaves | separates from the base surface of a heat receiving plate, and a 2nd fin is made into the base surface of a heat receiving plate. Since the outer shape has a step that gradually becomes thinner as it approaches, the surface area can be increased by forming the first fin having a function of transferring heat to the liquid refrigerant into the outer shape having a step, and Since the second fin having the same step along the outer shape is interposed, it is controlled so that the liquid refrigerant continuously flows to a region close to the surface of the first fin, and the substantial contact area per unit flow rate Therefore, the cooling performance can be improved even with a small flow rate of the liquid refrigerant, and it becomes easier to cope with downsizing.

  Also, when the distance between the top surface of the second fin and the base surface of the heat receiving plate is close to 150% or less of the distance between the first fin and the second fin adjacent to each other In addition to the effect that the liquid refrigerant can be controlled so that the liquid refrigerant flows continuously to a region close to the surface of the first fin for heat transfer, the heat transfer path with the heating element is short and the temperature is relatively low. Since it is possible to contact the base surface of the high heat receiving plate more efficiently, and a heat transfer effect equivalent to substantially increasing the contact area per unit flow rate with the liquid refrigerant can be obtained. Cooling performance can be improved even with a small flow rate of liquid refrigerant, and it becomes easier to cope with downsizing.

  Further, when the top surface of the second fin is brought into contact with the base surface of the heat receiving plate, the heat transfer path with the heating element is short and the temperature of the heat receiving plate is relatively high. As described above, in addition to the action that can be controlled so that the liquid refrigerant continuously flows to the region close to the surface of the first fin as described above, the second fin also heats the liquid refrigerant. Since it has a transmission function and the substantial contact area per unit flow rate increases, the cooling performance can be improved even with a small flow rate of liquid refrigerant, and it is easier to cope with downsizing.

According to the invention of claim 4 of the present invention, the first fin has a plate-like outer shape along the flow direction of the liquid refrigerant, and the second fin has a cylindrical outer shape. The first fin for heat transfer having the function of heat transfer can secure a sufficient contact area along the flow direction of the liquid refrigerant, and the second fin having a cylindrical outer shape is a flow path. The outer shape is such that the flow direction is forcibly changed in the horizontal direction without increasing the resistance and a small turbulent flow is likely to be generated downstream in the flow direction, so that a larger stirring action can be obtained, and the first fin and liquid Heat exchange with the refrigerant can be promoted and the cooling performance can be improved.

  In particular, since there is a laminar flow region with a relatively small amount of heat transfer near the surface of the first fin having a function of heat transfer to the liquid refrigerant, the turbulent flow effect by the second fin A heat transfer effect equivalent to substantially increasing the contact area per unit flow rate with the liquid refrigerant is obtained, and the cooling performance can be improved even with a small flow rate of the liquid refrigerant.

According to the invention described in claim 5 of the present invention, a plurality of first fins are erected along the flow direction of the liquid refrigerant, and the first fins adjacent to each other in the direction orthogonal to the flow direction of the liquid refrigerant. Since the second fin is erected on the upstream side of the gap, since the first fin for heat transfer is a plate-like outer shape with a short length, the amount of heat transfer existing near the surface is relatively small. While suppressing the laminar flow region from further shifting to the separation region where the flow of the liquid refrigerant stagnate, in addition, the turbulent flow effect of the second fin works more effectively, and the liquid refrigerant in contact with the first fin Since the cooling performance can be improved efficiently even when the flow velocity of the heat sink is slow or a heat receiver with a low flow rate of the liquid refrigerant, it is easier to cope with downsizing.

According to invention of Claim 6 of this invention, it is a structure of a 2nd fin, Comprising: The fin group of the plate-shaped external shape arranged in the direction orthogonal to the flow direction of a liquid refrigerant, and the direction through which a liquid refrigerant flows The cylindrical outer fin group arranged in the orthogonal direction is configured, and the fin groups with different outer shapes are adjacent to each other along the flow direction of the liquid refrigerant. A cylindrical outer fin group having an action to be generated in a plate and an outer fin group having a plate shape having an action of controlling the liquid refrigerant to flow continuously in an area close to the surface of the first fin. It is erected so as to be adjacent to each other along the direction in which the refrigerant flows, so that a synergistic effect of the respective actions can be obtained, and heat exchange with the liquid refrigerant can be further promoted.

  In addition, since the second fin for controlling the flow of the liquid refrigerant from the inner wall of the casing toward the heat receiving plate is erected, the second fin passes through the flow path of the gap between the first fins for heat transfer. By controlling the flow direction of the flowing liquid refrigerant and promoting heat exchange with the liquid refrigerant, not only can the cooling performance be improved easily even with a small liquid refrigerant flow rate, but also a simple structure can easily cope with downsizing. .

  In addition, when trying to erect the first fin on the heat receiving plate by die casting with relatively high productivity using aluminum alloy, copper alloy, zinc alloy, etc., the durability of the mold for molding, In order to obtain stable quality moldability without cracks, the thickness of the first fin and the gap between the first fins adjacent to each other should be at least about 0.8 to 1.0 mm. In order to increase the contact area with the liquid refrigerant, further narrowing the pitch requires another method that is complicated in manufacturing method such as chemical etching and inferior in mass productivity.

  However, a heat transfer effect equivalent to substantially increasing the contact area with the liquid refrigerant by using the heat receiver having a simple structure in which the second fin for appropriately controlling the flow of the liquid refrigerant is combined. Therefore, mass production of the heat receiver is improved, and inexpensive manufacturing is possible.

According to the seventh aspect of the present invention, since the heat receiver according to any one of the first to sixth aspects is provided, the heat receiver promotes heat exchange with the liquid refrigerant, thereby reducing the amount of liquid. Cooling performance can be easily improved even with the flow rate of the refrigerant, and it has the effect of being able to easily cope with downsizing with a simple structure, so the cooling performance as a cooling device is improved, and a relatively large amount of heat is generated. It becomes easy to deal with large heating elements and miniaturization and weight reduction.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each drawing, the heat receiving surface side is described as the lower side and the casing side as the upper side.

(Embodiment 1)
1 to 5, FIG. 1 is a partially cutaway perspective view of a heat receiver in Embodiment 1 of the present invention, FIG. 2 is a cross-sectional view taken along line AA in FIG. 1, and FIG. FIG. 3B is a perspective view from below of the partition member, FIG. 3C is a perspective view from above of the heat receiving plate, and FIG. FIG. 5A is a cross-sectional view taken along the arrow B, FIG. 5A is a cross-sectional view of the main part of the heat receiver 1 according to Embodiment 1 of the present invention, FIG. It is sectional drawing which showed the example.

  First, the main configuration of the heat receiver 1 including the centrifugal pump will be described with reference to FIG. 1 except for the heat receiving plate 2, the first fin 2a, the partition member 3, the second fin 3b, and the casing 4. Since these constituent members will be described later, they are not shown.

  The bottom of the heat receiver 1 having a substantially cylindrical outer shape is in contact with a heating element (not shown) such as a semiconductor element so that a good thermal connection can be obtained through a heat receiving surface described later. The heat receiving plate 2 is made of a metal material having good thermal conductivity such as an aluminum alloy.

  Then, a rectangular recess 2d that is slightly depressed is formed in the approximate center of the upper surface of the flat disk-shaped heat receiving plate 2, and a plate-like outer shape along the flow direction of the liquid refrigerant is formed on the inner surface of the recess 2d. A plurality of first fins 2a are erected.

  Here, the first fins 2a are for heat transfer, and a plurality of the first fins 2a are arranged so as to be substantially parallel with a uniform pitch in a direction orthogonal to the flow direction of the liquid refrigerant.

  Further, a casing 4 made of resin molding such as polyphenylene sulfide (PPS) or polyphenylene ether (PPE) so as to accommodate the first fin 2a is combined with the heat receiving plate 2, and the casing 4 A part of the space between the heat receiving plate 2 and the heat receiving plate 2 constitutes a flow path of the liquid refrigerant flowing inside the heat receiving device 1.

  Further, as will be described in detail later, the partition wall member 3 is sandwiched between the heat receiving plate 2 and the casing 4 to form a heat transfer chamber 5 described later between the heat receiving plate 2 and the impeller between the casing 4. (Not shown) is accommodated, and a pump chamber 6 is formed that circulates and drives the liquid refrigerant by using a centrifugal propulsive force generated by the rotational movement of the impeller.

  On the other hand, the side wall of the casing 4 is provided with a suction port 4a and a discharge port 4b that connect a pair of liquid transport paths of a cooling device (not shown), and the liquid refrigerant that has flowed in from the suction port 4a as indicated by an arrow is After the heat exchange with the first fin 2a while flowing in the direction from the heat transfer chamber 5 to the pump chamber 6 through the inside of the heat receiver 1, it flows out of the heat receiver 1 from the discharge port 4b as indicated by an arrow. To do.

  Next, FIG. 2 is a cross-sectional view taken along the line AA in FIG. 1, and the internal structure of the heat receiver 1 having a centrifugal pump will be described in detail with reference to FIG.

  In FIG. 2, as described above, the partition member 3 is sandwiched between the heat receiving plate 2 and the casing 4, and communicates with the heat receiving plate 2 between the suction heat transfer chamber 5 a, the circulating heat transfer chamber 5 b, and the space therebetween. While forming the heat transfer chamber 5 comprised by the flow path 5c etc., the pump chamber 6 which accommodates the impeller 7 between the casings 4 is formed.

  Here, the impeller 7 constituting the centrifugal pump is pivotally supported at a substantially central portion of the heat receiver 1, a plurality of open-type blades 7a are erected on the surface of the impeller 7 in a substantially radial manner, and the magnet rotor 8 is a blade. It is provided on the inner peripheral side surface of the car 7. Here, the impeller 7 may be configured separately from the magnet rotor 8, but it is preferable that the impeller 7 be an integrated impeller 7 that is magnetized in a portion that becomes the magnet rotor 8.

  When the impeller 7 rotates in the liquid refrigerant, the pressure of the liquid refrigerant on the outer peripheral side of the blade 7a becomes higher than the pressure of the liquid refrigerant at the inlet of the impeller 7 (the central portion indicated by K in FIG. 2). Further, since the pressure at the inlet of the impeller 7 is substantially the same as the back side pressure of the impeller 7 communicated by the small hole 7b, the liquid refrigerant passes through the back surface of the impeller 7 and passes through the small hole 7b to the inlet side. Reflux for a small amount. Thereby, compared with the case where there is no small hole 7b, the thrust force to the impeller 7 is reduced, and the rotation of the impeller 7 becomes smoother.

  The centrifugal pump built in the heat receiver 1 is small and has a size that is several tenths or one hundredth of that of a general centrifugal pump. The pump has a thickness of 3 mm to 50 mm, a representative dimension in the radial direction of 10 mm to 100 mm, a rotation speed of 1000 rpm to 8000 rpm, and a head of about 0.5 m to 10 m.

  Next, a stator 9 is provided on the inner peripheral side of the magnet rotor 8, a coil 10 for generating a magnetic field is wound around the stator 9, and an electric circuit for passing a current through the coil 10 is mounted on the circuit board 11.

  Here, the stator 9 is preferably formed by laminating a plurality of silicon steel plates in order to reduce eddy current loss, and a copper wire with an insulating film is suitable as the coil 10. The number of turns is optimized in view of the power supply voltage used and the line factor.

  Although not shown, a Hall element for detecting the rotational position of the magnet rotor 8, a current direction switching transistor and a diode are mounted on the circuit board 11.

  The casing 4 accommodates the impeller 7 and at the same time guides the liquid refrigerant, which is given a thrust in the centrifugal direction by the impeller 7, to the discharge port 4 b connected to the side surface thereof, and the suction port 4 a is also the casing 4. Connected in almost the same direction on the side of the.

  Further, the casing 4 is combined with the flange 2b formed on the outer peripheral portion of the heat receiving plate 2 in contact with each other, and a part of a predetermined space such as the pump chamber 6 which is the internal space passes through the flow path of the liquid refrigerant. Constitute. In the pump chamber 6, the liquid refrigerant to which the propulsive force is given by the rotational movement of the open type blade 7 a is guided to the discharge port 4 b.

  Furthermore, since the casing 4 has a complicated shape and requires a certain degree of heat resistance, it is more suitable to manufacture by resin molding such as polyphenylene sulfide (PPS) and polyphenylene ether (PPE).

  On the other hand, it is not preferable to manufacture the casing 4 from a metal material because eddy current loss occurs due to magnetic flux fluctuations generated by a magnetic circuit such as the stator 9.

  On the other hand, the heat receiving plate 2 is in direct contact with a heating element 12 such as a semiconductor element indicated by a two-dot chain line through a heat conductive grease or the like (not shown), so that its surface is made as flat as possible, Using metal materials such as copper, copper alloy, aluminum, aluminum alloy and the like having high heat conductivity and good heat dissipation, it is manufactured by casting, forging, machining, or a combination of these, such as die casting.

  Further, since the heat receiving plate 2 is made of a metal material having good thermal conductivity, its rigidity is increased. Even if the casing 4 is pressed toward the heating element 12 with a strong stress, the heat receiving plate due to the stress is used. 2 can be suppressed, and a gap can be prevented from being formed between the heating element 12 and the heat receiving surface 2c.

  If the heat receiving surface 2c can be pressed against the heat generating body 12 with the strong force, a heat conductive grease (not shown) applied between the heat generating body 12 and the heat receiving surface 2c can be thinly extended, thereby heat conduction. The thermal resistance of the functional grease can be reduced, and the parts can be prevented from coming off when the product is subjected to vibration or shock.

  Here, a heat receiving surface 2c which is a contact surface with a heating element 12 such as a semiconductor element indicated by a two-dot chain line is provided at the lower part of the heat receiving plate 2, and is slightly depressed in the approximate center of the upper surface which is the opposite surface. A rectangular recess 2d is formed, and a plurality of first fins 2a having a plate-like outer shape along the flow direction of the liquid refrigerant are erected on the inner surface of the recess 2d.

  The first fins 2a are for heat transfer, and a plurality of the first fins 2a are arranged so as to be substantially parallel with a uniform pitch in a direction orthogonal to the flow direction of the liquid refrigerant. Heat exchange is performed while contacting the liquid refrigerant flowing through the gap flow path 5c, and the heat received from the heating element 12 is efficiently transmitted to the liquid refrigerant.

  This flat disk-shaped heat receiving plate 2 has a simple structure that easily transfers the heat received from the heat receiving surface 2c to the first heat transfer fins 2a formed on the back surface thereof. Since the first fin 2a is accommodated in the casing 4 and is erected substantially perpendicular to the heat receiving plate 2, the heat transfer path from the heat receiving surface 2c to the first fin 2a can be set to the shortest distance.

  That is, the short heat transfer path means that the thermal resistance between the heat receiving surface 2c and the first fin 2a is small, and the heating element in which the surface temperature of the first fin 2a is in contact with the heat receiving surface 2c. Since the temperature can be made closer to the surface temperature of 12, the heat exchange is efficiently performed over a wide range while contacting the liquid refrigerant, and the cooling performance is improved.

  The first fins 2a have a plate-like outer shape along the flow direction of the liquid refrigerant, and are arranged in a direction orthogonal to the flow direction of the liquid refrigerant, so that the surface area in contact with the liquid refrigerant is easily increased. In addition, since the flow resistance of the liquid refrigerant flowing through the flow path 5c in the gap between the first fins 2a is suppressed, a small pressure loss is ensured and a sufficient flow rate is secured. can do.

  Furthermore, the 2nd fin 3b which controls the flow of a liquid refrigerant from the bottom face of the plate-shaped partition plate 3a of the partition member 3 facing the heat receiving plate 2 toward the heat receiving plate 2 is provided upright. The fin 3b also has a plate-like outer shape along the flow direction of the liquid refrigerant, and since the second fin 3b enters the gap between the first fins 2a adjacent to each other, the first fin 2a The second fin 3b is interposed in the flow path 5c between the gaps.

  The second fin 3b is controlled so that the liquid refrigerant continuously flows to a region close to the surface of the first fin 2a, so that the liquid refrigerant is more efficiently connected to the surface of the first fin 2a. Heat transfer effect equivalent to increasing the contact area per unit flow rate with the liquid refrigerant can be obtained, and the cooling performance can be improved even with a small flow rate of the liquid refrigerant. It becomes easy to deal with.

  Further, the first fin 2a and the second fin 3b extend linearly so as to be substantially parallel to each other from the suction heat transfer chamber 5a to the circumferential heat transfer chamber 5b, that is, the direction in which the liquid refrigerant flows. The liquid refrigerant is supplied in the extending direction of the first fin 2a through the suction heat transfer chamber 5a that is provided and communicated with the suction port 4a, and is sandwiched between the first fin 2a and the second fin 3b. The liquid refrigerant having a uniform flow rate is sent to the flow path 5c in the gap.

  Therefore, despite the simple structure, the liquid refrigerant stays little and the liquid refrigerant can flow stably in the flow path 5c, and the cooling performance can be improved.

  On the other hand, the liquid refrigerant that has flowed in from the suction port 4a as shown by the arrow passes through the suction communication port 3e formed on the side surface of the partition wall member 3 and then passes through the suction heat transfer chamber 5a, so that the plurality of first fins While exchanging heat with 2a, it flows through the flow path 5c in the gap into the circulating heat transfer chamber 5b, and is divided into two directions on the left and right of the traveling direction while colliding with the cylindrical wall 3c of the partition wall member 3, and this circulating heat transfer chamber While being mixed with the subsequent liquid refrigerant at 5 b, finally, it passes through the through hole 3 d formed on the side of the circumferential heat transfer chamber 5 b of the partition wall member 3 and is sent out to the pump chamber 6.

  Here, since the second fin 3b is not interposed in the region below the through hole 3d, the flow resistance of the region is reduced, and the liquid refrigerant directly forms the dish-shaped partition wall member 3 from the flow channel 5c. The structure is such that it passes through a through-hole 3d opened in a half-moon shape on the bottom surface of the partition plate 3a and is easily sent out to the pump chamber 6 side.

  That is, with such a simple structure, the liquid refrigerant flows into the central portion of the heat receiving plate 2 as described above, and finally passes through the through hole 3d of the partition wall member 3 until it is sent out to the pump chamber 6 side. Since the heat received from the heating element 12 is transferred to the surface of the first fin 2a for heat transfer and the liquid refrigerant driven to circulate by the rotational movement of the impeller 7 is in contact with the liquid. The refrigerant can efficiently exchange heat with the first fins 2a.

  The first fin 2a has a plate-like outer shape, and extends linearly from the suction heat transfer chamber 5a to the circumferential heat transfer chamber 5b so as to be substantially parallel to the direction in which the liquid refrigerant flows. As a result, the flow resistance is small and the contact area with the liquid refrigerant can be significantly increased to increase the heat exchange efficiency.

  Here, the structure of the heat receiver 1 will be further described with reference to FIG. 2. A shaft 13 made of a material such as stainless steel having high corrosion resistance is integrally fixed to the center of the casing 4 by insert molding. The impeller 7 is rotatably supported.

  Further, the partition member 3 having the above-described dish-shaped partition plate 3 a is fitted with the casing 4 to form the pump chamber 6, and is sandwiched between the casing 4 and the flange portion 2 b of the heat receiving plate 2. The sealing member 14 such as an O-ring prevents liquid refrigerant from leaking between the casing 4 and the heat receiving plate 2, and the circulating heat transfer chamber 5 b is a closed circuit formed between the partition wall member 3 and the heat receiving plate 2. ing.

  The partition member 3 is also complicated in shape like the casing 4 and is required to have heat resistance. Therefore, the partition member 3 is preferably manufactured by resin molding such as polyphenylene sulfide (PPS) or polyphenylene ether (PPE).

  When assembling the heat receiver 1 described above, first, the partition member 3 is mounted on the heat receiving plate 2 and then the impeller 7 is inserted into the shaft 13 integrally fixed with the casing 4 by insert molding. Next, the heat receiving plate 2 is fitted into the casing 4 and fixed using screws or the like (not shown).

  On the other hand, the coil 10 is wound around the stator 9 in a separate process, and the circuit board 11 on which electronic components for rotating the impeller 7 are mounted is attached to the stator 9. After this assembly is inserted into the recess of the casing 4, a filler (not shown) is poured, and then the filler is cured using a thermostatic bath or the like.

  The reason for using the filler is to dissipate the electronic components mounted on the circuit board 11 and to improve reliability by preventing direct contact with the circuit board 11 even if liquid refrigerant leaks. Such a filler is preferably a urethane-based or epoxy-based potting agent.

  Next, the operation of the centrifugal pump provided in the heat receiver 1 will be described.

  First, when the circuit board 11 is operated and an alternating magnetic field is generated in the stator 9, the impeller 7 integrated with the magnet rotor 8 is rotated by the alternating magnetic field, giving momentum to the liquid refrigerant and causing the central portion to have a negative pressure. Become.

  Thereby, the liquid refrigerant flows in from the suction port 4 a, passes through the suction communication port 3 e, and flows into the suction heat transfer chamber 5 a that is a space sandwiched between the heat receiving plate 2 and the partition wall member 3. The inflowing liquid refrigerant is located directly above the heating element 12 and efficiently takes away the heat of the first fins 2a that has become high temperature due to heat conduction.

  After that, the liquid refrigerant flows along the first fin 2a, reaches the outflow side end portion thereof, and strikes the cylindrical wall 3c of the partition wall member 3 in the circulating heat transfer chamber 5b, and moves to the left and right with respect to the traveling direction. Are divided in two directions. The diverted liquid refrigerant circulates in the circulating heat transfer chamber 5b while being mixed with the subsequent liquid refrigerant, and again because the inlet of the impeller 7 (the central portion indicated by K in FIG. 2) has a negative pressure. Suctioned in the center direction of the first fin 2a, passes through the through-hole 3d opened in a half-moon shape on the slightly circulating heat transfer chamber 5b side of the bottom surface of the dish-shaped partition plate 3a of the partition member 3, and enters the pump chamber 6. Sent out.

  The liquid refrigerant sent to the pump chamber 6 is finally given a centrifugal propulsive force by the rotational movement of the impeller 7 and guided to the outer peripheral portion of the pump chamber 6, and the discharge communication port 3 f to be described later is passed through. As shown by the arrow, it flows out from the discharge port 4b.

  Here, using FIGS. 3A to 3C, although partially overlapping with the above-described contents, the flow of the liquid refrigerant will be supplementarily described.

  3A is a perspective view of the partition wall member 3 from above, FIG. 3B is a perspective view of the partition wall member 3 from below, and FIG. 3C is a view of the heat receiving plate 2 from above. FIG.

  A rectangular suction opening 3e is formed on the side surface of the partition member 3, and the liquid refrigerant flowing in from the suction port 4a shown in FIG. 2 passes through the suction connection port 3e to pass through the heat receiving plate 2 and the partition member 3. The liquid refrigerant flows into a suction heat transfer chamber 5a (see FIG. 2) formed between the two.

  Here, a rectangular recess 2d that is slightly depressed is formed in the approximate center of the upper surface of the flat disk-shaped heat receiving plate 2, and a plurality of first fins 2a having a plate-like outer shape are formed on the inner surface of the recess 2d. It is erected.

  The liquid refrigerant that has flowed into the suction heat transfer chamber 5a passes through the flow path 5c (see FIG. 2) between the first fin 2a for heat transfer and the second fin 3b that controls the flow of the liquid refrigerant. After exchanging heat while flowing, it collides with the cylindrical wall 3c of the partition wall member 3 and is divided into two directions left and right with respect to the traveling direction.

  Then, while mixing with the subsequent liquid refrigerant, it passes through the half-moon-shaped through hole 3d opened on the side of the circumferential heat transfer chamber 5b on the bottom surface of the partition plate 3a of the partition member 3, and enters the pump chamber 6 (see FIG. 2). It is to be sent out.

  Further, since the second fin 3b is not interposed in the region below the through hole 3d, the flow resistance of the region is reduced, and the liquid refrigerant directly passes through the through hole 3d from the flow channel 5c and is pumped. It is structured to be easily sent out to the chamber 6 side.

  Furthermore, the liquid refrigerant sent out to the pump chamber 6 is finally given a momentum which becomes a propulsive force in the centrifugal direction by the rotational motion of the impeller 7 (see FIG. 2), and is guided to the outer peripheral portion of the pump chamber 6. Then, it flows out of the heat receiver 1 from the discharge port 4b (see FIG. 2) through the discharge communication port 3f.

  As described above, the heat receiver 1 including the centrifugal pump according to the first embodiment has the function of transmitting the received heat to the liquid refrigerant from the surfaces of the heat receiving plate 2 and the first fin 2a, and the casing 4 Since the partition member 3 is provided at a predetermined position between the heat receiving plate 2 and has a pump function of rotating the impeller 7, the cooling device including the heat receiver 1 is used for circulation driving of liquid refrigerant. Since a separate pump is not required, the entire apparatus can be easily downsized.

  Next, FIG. 4 is a cross-sectional view taken along the line BB in FIG. 2, and the first fin 2a and the second fin 3b, which are the main parts of the present invention, will be described in detail with reference to FIG.

  In addition, about the content which overlaps with description of FIG.2 and FIG.3, description is partially abbreviate | omitted.

  First, as shown in FIG. 4, a rectangular recess 2d that is slightly depressed is formed in the approximate center of the upper surface of the flat disk-shaped heat receiving plate 2, and a plurality of first fins are formed on the inner surface of the recess 2d. 2a is erected at an equal pitch substantially parallel to the flowing direction of the liquid refrigerant.

  Moreover, since the first fin 2a is formed integrally with the heat receiving plate 2 by die casting using a metal material having good thermal conductivity such as an aluminum alloy, a copper alloy, or a zinc alloy, the heating element 12 has a function of transferring heat to the liquid refrigerant in contact with the surface on the back side of the heat receiving surface 2c, which is thermally connected and has the highest temperature.

  The first fins 2a are erected vertically with respect to the base surface 2e of the recess 2d, which is the surface on the back side of the heat receiving surface 2c, and have a plate-like outer shape along the flow direction of the liquid refrigerant. Since the flow path 5c is formed in the gap between the adjacent first fins 2a, the heat received from the heating element 12 is efficiently transferred to the liquid refrigerant while in contact with the liquid refrigerant flowing through the flow path 5c. Is doing.

  Since the first fin 2a has a plate-like outer shape along the flow direction of the liquid refrigerant, it is possible to easily increase the surface area in contact with the liquid refrigerant, and between the first fins 2a. Since a large flow resistance against the liquid refrigerant flowing through the gap flow path 5c is suppressed, the pressure loss is small and a sufficient flow rate can be secured.

  Furthermore, the 2nd fin 3b is standingly arranged in the direction of the heat receiving plate 2 from the surface facing the heat receiving plate 2 of the partition member 3, and this 2nd fin 3b is also plate-shaped along the flow direction of a liquid refrigerant. The second fin 3b is inserted into the gap between the first fins 2a adjacent to each other in the outer shape.

  Then, it enters until the distance between the top surface 3g of the second fin 3b and the base surface 2e becomes 150% or less of the distance between the first fin 2a and the second fin 3b adjacent to each other. Therefore, the liquid refrigerant is controlled so as to continuously flow to a region close to the surface of the first fin 2a for heat transfer, and the liquid refrigerant contacts the surface of the first fin 2a more effectively. In addition, a heat transfer effect equivalent to increasing the contact area per unit flow rate with the liquid refrigerant can be obtained, the cooling performance can be improved even with a small flow rate of the liquid refrigerant, and it is easy to cope with downsizing.

  Further, the first fin 2a and the second fin 3b are linearly adjacent to and substantially parallel to each other along the direction from the suction heat transfer chamber 5a to the circulating heat transfer chamber 5b, that is, the direction in which the liquid refrigerant flows. Since the liquid refrigerant is supplied in the extending direction of the first fin 2a via the suction heat transfer chamber 5a communicating with the suction port 4a, the first fin 2a and the second fin The liquid refrigerant having a uniform flow rate is fed into the flow path 5c between the gaps 3b, and the liquid refrigerant stays little in the flow path 5c in spite of its simple structure. And cooling performance can be improved.

  Next, using the cross-sectional view of the main part of the heat receiver 1 according to Embodiment 1 of the present invention in FIG. 5 (a) and the cross-sectional views showing the modifications of FIGS. 5 (b) and (c), A modification of the second fin 3b will be described.

  As shown in FIG. 5 (a), the second fin 3b enters the flow path 5c in the gap between the first fins 2a, and the liquid refrigerant continuously flows into a region close to the surface of the first fin 2a. In addition to controlling to flow, the distance between the top surface 3g of the second fin 3b and the base surface 2e is 150, which is the distance of the gap between the first fin 2a and the second fin 3b adjacent to each other. %, The liquid refrigerant is not only on the surface of the first fin 2a but also has a short heat transfer path with the heating element 12 (not shown) and the base surface 2e of the heat receiving plate 2 having a relatively high temperature. In addition, the liquid refrigerant can contact the surface of the first fin 2a and the base surface 2e of the heat receiving plate 2 more effectively and substantially contact with the liquid refrigerant per unit flow rate. A heat transfer effect equivalent to increasing the area can be obtained. It also can improve the cooling performance with less liquid refrigerant flow rate, corresponding also becomes easier for miniaturization.

  In addition, as shown in FIG. 5B, when the top surface 3g of the second fin 3b is in contact with the base surface 2e of the heat receiving plate 2, the heat transfer path with the heat receiving surface 2c is short. Since direct heat conduction from the base surface 2e of the heat receiving plate 2 having a high target temperature to the second fin 3b can be obtained, as described above, the continuous flow to the channel 5c in the region close to the surface of the first fin 2a. In addition to the action that can be controlled to flow through the liquid refrigerant, the second fin 3b also has a function of heat transfer to the liquid refrigerant, which increases the substantial contact area per unit flow rate. Therefore, the cooling performance can be improved even with a small flow rate of the liquid refrigerant, and it becomes easier to cope with downsizing.

  In this case, the material of the partition member 3 is not made of resin, but is manufactured by die casting using a metal material having good thermal conductivity such as an aluminum alloy, a copper alloy, or a zinc alloy as the material of the heat receiving plate 2. More preferably.

  Further, as shown in FIG. 5 (c), the first fin 2a has an outer shape having a step 2f that gradually becomes thinner as it moves away from the base surface 2e of the heat receiving plate 2, and the second fin 3b is Since the outer shape has a step 3h that gradually becomes thinner as it approaches the base surface 2e of the heat receiving plate 2, the surface area of the first fin 2a for heat transfer having a function of heat transfer to the liquid refrigerant is further increased. Further, since the second fin 3b having the same step 3h is interposed along the outer shape thereof, the flow of the liquid refrigerant can be controlled in a region close to the surface of the first fin 2a. Since the substantial contact area per flow rate is also increased, the cooling performance can be improved even with a small flow rate of the liquid refrigerant, and the reduction in size is facilitated.

  Further, since the top surface 3g of the second fin 3b is close to the base surface 2e of the heat receiving plate 2, the liquid refrigerant is not only transferred to the surface having the step 2f of the first fin 2a but also to the heat receiving surface 2c. The path can be made to contact the base surface 2e of the heat receiving plate 2 having a short path and a relatively high temperature by heat conduction, and the liquid refrigerant can more efficiently contact the surface of the first fin 2a and the base of the heat receiving plate 2. A heat transfer effect equivalent to increasing the contact area per unit flow rate with the liquid refrigerant in contact with the surface 2e can be obtained, and the cooling performance can be improved even with a small flow rate of the liquid refrigerant. It becomes easier to deal with.

  The second fin 3b shown in FIG. 5 (c) has an outer shape having two steps 3h in the standing direction from the base surface 2e to the top surface 3g. Needless to say, it may be set to one level.

6 to 8, FIG. 6 is a partially cutaway perspective view of the heat receiver 1 for explaining a reference example of the present invention, FIG. 7A is a cross-sectional view taken along the line CC in FIG. 7B is a cross-sectional view taken along the arrow D-D in FIG. 7A, FIG. 8A is a cross-sectional view taken along the line E-E in FIG. 7B, and FIG. -E arrow sectional drawing, (c) is the EE arrow sectional drawing which showed the modification.

First, the main configuration of the heat receiver 1 that describes the reference example of the present invention will be described with reference to FIG. 6, but the same components as those described in Embodiment 1 are denoted by the same reference numerals and overlapped. A part of the description is omitted.

  The bottom surface of the heat receiver 1 having a substantially rectangular parallelepiped shape is in contact with a heating element (not shown) such as a semiconductor element so that a good thermal connection can be obtained via a heat receiving surface 2c described later. The rectangular heat receiving plate 2 is made of a metal material having good thermal conductivity such as an aluminum alloy.

  A rectangular recess 2d that is slightly depressed is formed in the approximate center of the upper surface of the flat rectangular heat receiving plate 2, and a plate-like outer shape along the flow direction of the liquid refrigerant is formed on the inner surface of the recess 2d. A plurality of first fins 2a are provided upright.

  Here, the first fins 2a are for heat transfer, and a plurality of the first fins 2a are arranged so as to be substantially parallel with a uniform pitch in a direction orthogonal to the flow direction of the liquid refrigerant.

  In addition, a casing 15 made of a metal material having a good thermal conductivity such as copper, copper alloy, aluminum, aluminum alloy or the like so as to accommodate the first fin 2a is combined with the heat receiving plate 2. In addition, a part of the space between the casing 15 and the heat receiving plate 2 constitutes a flow path of the liquid refrigerant that flows inside the heat receiver 1.

  That is, the heat transfer chamber 16 including the suction heat transfer chamber 16a, the circulating heat transfer chamber 16b, and the flow path 5c communicating between the casing 15 and the heat receiving plate 2 is formed.

  On the other hand, a suction port 15a and a discharge port 15b that connect a pair of liquid transport paths of a cooling device (not shown) are provided on both side walls of the casing 15, respectively, and flowed in from the suction port 15a as indicated by arrows. The liquid refrigerant passes through the suction heat transfer chamber 16a, flows through the flow path 5c in the gap while exchanging heat with the plurality of first fins 2a, flows into the circulating heat transfer chamber 16b, and continues in the circulating heat transfer chamber 16b. Finally, it flows out of the heat receiver 1 from the discharge port 15b as shown by the arrow while being mixed with the liquid refrigerant.

  Here, the plurality of first fins 2a are linearly extended so as to be substantially parallel to the direction of the circulating heat transfer chamber 16b from the suction heat transfer chamber 16a, and the suction heat transfer communicated with the suction port 15a. The liquid refrigerant is supplied in the extending direction of the first fin 2a via the chamber 16a, and the flow path 5c is formed in the gap between the plurality of first fins 2a substantially parallel to the first fin 2a. Since the liquid refrigerant is fed at a uniform flow rate, the liquid refrigerant can be stably flowed into the flow path 5c despite the simple structure, and the cooling performance can be improved. it can.

  Further, a plurality of cylindrical second fins 15c are erected from the inner wall of the casing 15 in the direction of the heat receiving plate 2 along the flow direction of the liquid refrigerant, and the first fins 2a adjacent to each other. The second fin 15c enters the gap.

  Further, the second fin 15c has a cylindrical outer shape so as to forcibly change the flow direction of the liquid refrigerant flowing along the first fin 2a to the lateral direction, and the heat transfer to the liquid refrigerant. The flow in the laminar flow region present near the surface of the first fin 2a having a function and having a relatively small heat transfer amount is forcibly changed in the lateral direction by the second fin 15c, and is downstream of the flow direction. When a minute turbulent flow is generated in this, a stirring action can be easily obtained, heat exchange between the first fin 2a and the liquid refrigerant can be promoted, and cooling performance can be improved.

  On the other hand, as shown in FIGS. 7 (a) and 7 (b), the first fin 2a stands vertically with respect to the base surface 2e of the concave portion 2d at substantially the center of the upper surface of the flat rectangular plate-shaped heat receiving plate 2. Since the flow path 5c is formed in the gap between the first fins 2a with a plate-like outer shape that is provided along the flow direction of the liquid refrigerant, it receives heat while contacting the liquid flowing through the flow path 5c. The heat received from the surface 2c is efficiently transmitted to the liquid refrigerant.

  The first fins 2a have a plate-like outer shape along the flow direction of the liquid refrigerant, and a plurality of the first fins 2a are arranged so as to be substantially parallel with a uniform pitch in a direction orthogonal to the flow direction of the liquid refrigerant. The surface area in contact with the first fin 2a can be easily increased, and a large flow resistance against the liquid refrigerant flowing through the flow path 5c in the gap between the first fins 2a is suppressed. It becomes pressure loss and a sufficient flow rate can be secured.

  Furthermore, a plurality of cylindrical second fins 15c are erected along the flow direction of the liquid refrigerant from the inner wall of the casing 15 toward the heat receiving plate 2 and flow along the first fins 2a. It has a cylindrical outer shape so as to forcibly change the flow direction of the liquid refrigerant laterally by the second fins 15c, and is close to the surface of the first fin 2a having a function of transferring heat to the liquid refrigerant. The flow in the laminar flow region having a relatively small amount of heat transfer is forced to be laterally changed by the second fins 15c, and a minute turbulent flow is generated on the downstream side in the flow direction. Is easily obtained, heat exchange between the first fin 2a and the liquid refrigerant can be promoted, and the cooling performance can be improved.

  In addition, since the first fin 2a has a plate-like outer shape, the first fin 2a having a function of heat transfer to the liquid refrigerant can ensure a sufficient contact area along the flow direction of the liquid refrigerant, In addition, the cylindrical outer shape of the second fin 15c is an outer shape that easily changes the flow direction to the lateral direction without greatly increasing the flow path resistance and easily generates a turbulent flow region downstream of the flow direction. A large stirring action is obtained, heat exchange between the first fin 2a and the liquid refrigerant can be promoted, and the cooling performance can be improved.

  FIG. 8A is a cross-sectional view taken along the line E-E in FIG. 7B, and the liquid refrigerant flowing through the flow paths 5c in the gaps between the plurality of first fins 2a having a plate-like outer shape is substantially uniform. When the second fin 15c having a cylindrical outer shape standing upright with a pitch is changed in the lateral direction as shown by the arrow, a minute turbulent flow is generated there and the stirring action can be easily obtained. Therefore, heat exchange between the first fin 2a and the liquid refrigerant can be promoted, and the cooling performance can be improved.

8 (b) is a modification to the positional relationship of the first fin 2g and the second fin 15c in FIG. 8 (a).

  Here, a plurality of first fins 2g each having a slightly shorter plate-like outer shape are provided in the flow direction of the liquid refrigerant, and are adjacent to each other in a direction orthogonal to the flow direction of the liquid refrigerant. Since the second fin 15c having a cylindrical outer shape is erected on the upstream side of the gap of the first fin 2g, the length of the first fin 2g is slightly short, so that the first fin 2g is relatively close to the surface. The laminar flow region with a small amount of heat is further suppressed from moving to the separation region where the flow of the liquid refrigerant stagnate, and the second fins 15c effectively generate a turbulent flow region. The cooling performance can be improved efficiently even when the flow rate of the liquid refrigerant in contact with the first fin 2g having the heat transfer function is low or the heat receiver with a low flow rate of the liquid refrigerant can be easily reduced. Become.

Further, FIG. 8 (c) is another variation on the first fin 2a and the second fin 15c, 15d positional relationship of FIG. 8 (a).

  Here, the configuration of the second fins 15c and 15d is a group of fins having a plate-like outer shape arranged in a direction orthogonal to the flow direction of the liquid refrigerant and a circle arranged in a direction orthogonal to the flow direction of the liquid refrigerant. A fin group having a columnar outer shape is formed, and the fin groups having different outer shapes are adjacent to each other along the direction in which the liquid refrigerant flows, so that the region close to the surface of the first fin 2a is continuous. Direction in which the liquid refrigerant flows through the plate-like outer fin group having an action that can be controlled so that the liquid refrigerant flows in a continuous manner and the cylindrical outer fin group having an action for forcibly generating a minute turbulent flow Therefore, a synergistic effect of the respective actions can be obtained, and heat exchange with the liquid refrigerant can be further promoted.

In the above description, the height, length, size, number, positional relationship, pitch, and the like of the first fins 2a, 2g and the second fins 3b, 15c, 15d are limited to the first embodiment. However, the fins may be appropriately selected in consideration of the structure of the heat receiver 1 and the cooling effect, and the fin shape is preferably a plate shape or a cylindrical outer shape, but has the same function and effect. Any other shape may be used.

Further, when the first fins 2a, 2g and the second fins 3b, 15c, 15d have a plate-like outer shape, it is not necessary to have a flat plate shape extending linearly as in the first embodiment. Alternatively, a plate-like outer shape that is curved or bent may be used.

  Further, as for the production method thereof, a method other than die casting, for example, a fin prepared separately is joined to the heat receiving plate 2 or the casing 15 by brazing or welding, or forging, powder metallurgy, extrusion molding, It may be formed by wire cutting, electric discharge machining, or the like.

(Embodiment 2 )
FIG. 9 is an overall configuration diagram in which the cooling device according to Embodiment 2 of the present invention is mounted on a notebook PC.

  In the first embodiment, a cooling device is mounted inside a casing 17 of a notebook PC that is an electronic device, and receives heat by contacting a heating element 12 such as an MPU under a keyboard 18 of the notebook PC. The heat receiver 1 with the described centrifugal pump is mounted. The heating element 12 is mounted on the substrate 19, and a radiator 20 that dissipates the heat of the liquid refrigerant received from the heating element 12 to the outside is disposed on the back surface (back side) of the notebook PC display, and a pair of liquid transport paths Both ends of 21 are connected to each of the heat receiver 1 and the radiator 20, and the liquid refrigerant circulates in the closed circuit.

  As the liquid refrigerant, an antifreeze solution such as an ethylene glycol aqueous solution or a propylene glycol aqueous solution is appropriate, and since copper, copper alloy, or the like is used as the material of the heat receiving plate 2, it is desirable to add an anticorrosive additive.

  On the other hand, the radiator 20 is made of a thin plate material such as copper, copper alloy, aluminum, or ashmium alloy, which has a high thermal conductivity and good heat dissipation, and a liquid refrigerant flow path, a reserve tank, and the like are formed therein. The pair of liquid transport paths 21 is composed of a rubber tube such as a flexible rubber having a low gas permeability, for example, butyl rubber, fluorine rubber, etc., in order to ensure flexibility in piping layout.

  Further, a fan device may be separately provided for the purpose of improving the cooling effect by forcibly applying air to the radiator 20.

  As described in the first embodiment, the heat receiver 1 of this cooling device is a heat receiver that connects the pair of liquid transport paths 21 and allows the liquid refrigerant to flow inside, and has a heating element 12 on one surface. A heat receiving surface 2c that is thermally connected to the heat receiving plate 2 is provided, and a heat receiving plate 2 in which the first fins 2a for heat transfer are erected on the back surface, and the heat receiving plate 2 so as to accommodate the first fin 2a. A pump chamber 6 sandwiched between the casing 4 and the heat receiving plate 2 and the casing 4 to form a heat transfer chamber 5 between the heat receiving plate 2 and accommodate the impeller 7 between the casing 4 and the casing 4. And a partition member 3 having a through hole 3d at the center, and the liquid refrigerant flowing into the heat transfer chamber 5 is transferred to the heat of the first fin 2a, and the partition member is transferred from the heat transfer chamber 5 to the liquid refrigerant. The liquid refrigerant that has flowed into the pump chamber 6 through the 3 through holes 3 d is accommodated in the pump chamber 6. Gives propulsion by rotation movement of the impeller 7, a second fin 3b for controlling the flow of liquid coolant are erected from the surface facing the heat receiving plate 2 of the partition member 3 in the direction of the heat-receiving plate 2.

  Therefore, since this cooling device includes such a heat receiver 1, the heat receiver 1 promotes heat exchange with the liquid refrigerant, and can easily improve the cooling performance even with a small liquid refrigerant flow rate. Since it has the effect of being able to easily cope with downsizing with a simple structure, the cooling performance as a cooling device is improved, and it is compatible with heating elements with relatively large heat generation and downsizing and weight reduction Is also easier.

In addition, since the heat receiver 1 of the second embodiment also has a pump function, a separate pump is not necessary in the liquid circulation path, and the entire casing 17 of the notebook PC can be easily reduced in size and weight. Can be realized.

  The present invention can be applied to a cooling device that cools a heating element mounted on an electronic device by circulation of a liquid refrigerant.

The partially cutaway perspective view of the heat receiver in Embodiment 1 of the present invention AA arrow sectional view of FIG. (A) Perspective view from above of partition member, (b) Perspective view from below of partition member, (c) Perspective view from above of heat receiving plate BB arrow sectional view of FIG. (A) Cross-sectional view of main part of heat receiver 1 according to Embodiment 1 of the present invention, (b) Cross-sectional view showing its modification, (c) Cross-sectional view showing its modification Partially cutaway perspective view of a heat receiver for explaining a reference example of the present invention (A) CC arrow sectional drawing of FIG. 6, (b) DD arrow sectional drawing of FIG. 7 (a). (A) EE arrow sectional view of FIG.7 (b), (b) EE arrow sectional drawing which showed the modification, (c) EE arrow sectional drawing which showed the modification. Overall configuration diagram in which a cooling device according to Embodiment 2 of the present invention is mounted on a notebook PC (A) An exploded perspective view of the heat receiver described in (Patent Document 1), (b) an external perspective view thereof, and (c) a partially enlarged sectional view of the AA cross section. (A) Sectional view of the cooling device described in (Patent Document 2), (b) Partial enlarged sectional view

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Heat receiver 2 Heat receiving plate 2a 1st fin 2b Eaves part 2c Heat receiving surface 2d Recessed part 2e Base surface 2f Step 2g 1st fin 3 Partition member 3a Partition plate 3b 2nd fin 3c Cylindrical wall 3d Through-hole 3e Suction communication port 3f Discharge communication port 3g Top surface 3h Step 4 Casing 4a Suction port 4b Discharge port 5 Heat transfer chamber 5a Suction heat transfer chamber 5b Circulating heat transfer chamber 5c Flow path 6 Pump chamber 7 Impeller 7a Blade 7b Small hole 8 Magnet rotor 9 Stator DESCRIPTION OF SYMBOLS 10 Coil 11 Circuit board 12 Heating body 13 Shaft 14 Seal member 15 Casing 15a Suction port 15b Discharge port 15c 2nd fin 15d 2nd fin 16 Heat transfer chamber 16a Suction heat transfer chamber 16b Circumferential heat transfer chamber 17 Case 18 Keyboard 19 Substrate 20 Radiator 21 Liquid transport path K Impeller entrance

Claims (7)

A heat receiver that connects a pair of liquid transport paths and allows a liquid refrigerant to flow therein, wherein a heat receiving surface that is thermally connected to a heating element is provided on one surface, and a first fin for heat transfer is provided on the back surface thereof A heat receiving plate erected, a casing combined with the heat receiving plate so as to accommodate the first fin, and the heat receiving plate and the casing, and are interposed between the heat receiving plate and the heat receiving plate. Forming a heat chamber and a pump chamber for accommodating an impeller between the casing and a partition member having a through hole in the center, and the liquid refrigerant flowing into the heat transfer chamber The liquid refrigerant that has transferred the heat of the first fin and passed through the through hole of the partition member from the heat transfer chamber and flowed into the pump chamber is caused by the rotational movement of the impeller housed in the pump chamber. Providing a propulsive force, front from the surface of the partition member facing the heat receiving plate Heat receiver, characterized in that the erected second fin for controlling the flow of liquid coolant toward the heat receiving plate. The first fin has a plate-like outer shape along the flow direction of the liquid refrigerant, the second fin has a plate-like outer shape along the flow direction of the liquid refrigerant, and the first fin is a liquid 2. The heat receiver according to claim 1, wherein a plurality of the second fins are inserted into a gap between the first fins that are arranged in a direction orthogonal to the flow direction of the refrigerant and are adjacent to each other. The first fin has an outer shape having a step that gradually thins as it moves away from the base surface of the heat receiving plate, and the step that gradually thins the second fin as it approaches the base surface of the heat receiving plate. The heat receiver according to claim 2, wherein the heat receiver has an outer shape having a shape. The heat receiver according to claim 2, wherein the first fin has a plate-like outer shape along a flow direction of the liquid refrigerant, and the second fin has a cylindrical outer shape. A plurality of the first fins are erected along the flow direction of the liquid refrigerant, and the second fins are disposed upstream of the gap between the first fins adjacent to each other in the direction orthogonal to the flow direction of the liquid refrigerant. The heat receiver according to claim 4, wherein The fins having a plate-like outer shape arranged in the direction orthogonal to the flow direction of the liquid refrigerant and the columnar outer fins arranged in the direction orthogonal to the direction of the liquid refrigerant flowing, which are the configurations of the second fins The heat receiver according to claim 2, wherein the fin groups having different outer shapes are adjacent to each other along a direction in which the liquid refrigerant flows. Cooling apparatus characterized by comprising a heat receiver according to any of the preceding claims 1 to.

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