JP2007123564A - Heat exchanging device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a thermoelectric module which is high in heat dissipating properties and capable of maintaining its excellent long-term reliability in a high-temperature and high-humidity environment. <P>SOLUTION: A heat exchanging device is equipped with the thermoelectric module which is provided with a pair of supporting substrates 1a and 1b which are opposed to each other, and the adjacent thermoelements 3a and 3b which are arranged between the one primary surfaces of the supporting substrates 1a and 1b and electrically connected together with electrodes; and a fin 7 which is provided to at least the other primary surface of one of the pair of supporting substrates 1a and 1b, and equipped with heat exchanging boards 7a that are arranged nearly in parallel standing nearly vertical to the primary surfaces of the supporting substrates 1a and 1b. Moreover, a space between the adjacent heat exchanging boards 7a and 7a located near a center in the arrangement direction of the heat exchanging boards 7a is set smaller than that between the adjacent heat exchanging boards 7a and 7a arranged near both ends in the arrangement direction of the heat exchanging boards 7. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention includes a heat exchange fin for cooling or heat dissipation, and is suitably used for an air conditioner, a cold / hot storage, a heating element cooling, a thermoelectric power generation, etc., and particularly a thermoelectric module suitable for an automobile seat cooling or heating application. The present invention relates to a heat exchange device using

  Conventionally, a heat exchange device using a thermoelectric module using the Peltier effect has been widely used as a heat exchange device for cooling purposes in a thermostatic bath, a refrigerator, a semiconductor manufacturing device, or the like. Moreover, since both cooling and heating are possible by reversing an electric current, it is used also for the use of a cold storage and an air conditioner. Further, since this thermoelectric module can also take out electricity by giving a temperature difference, it has been attracting attention as a thermoelectric power generator.

  As a typical structure of a heat exchange device using a thermoelectric module using these Peltier effects, as shown in FIG. 1, wiring conductors (electrodes) 2a and 2b are formed on the surfaces of support substrates 1a and 1b, respectively. The thermoelectric element 3 (N-type thermoelectric element 3a and P-type thermoelectric element 3b) is sandwiched between the wiring conductors 2a and 2b and electrically connected in series, and heat is applied to the support substrates 1a and 1b. Replacement fins are attached. The N-type thermoelectric elements 3 a and the P-type thermoelectric elements 3 b are alternately arranged, connected by wiring conductors 2 a and 2 b so as to be electrically in series, and further connected to the external connection terminal 4. As a result, a DC voltage can be applied from the external connection terminal 4 to the thermoelectric element 3, and heat can be absorbed or generated according to the direction of the current.

  The amount of heat absorbed in the thermoelectric module is radiated from the heat radiating surface, and at the same time, the heat radiating surface needs to radiate the heated Joule heat. Therefore, in order to use the energy of heat absorption or heat generation in a cold storage or air conditioner, it is necessary to make the heat radiation surface easy to radiate heat. If the heat dissipation characteristics are poor, the amount of heat that cannot be dissipated moves to the cooling surface, which greatly reduces the cooling characteristics. Therefore, it is particularly important to improve the heat dissipation characteristics in order to increase the cooling efficiency of the heat exchange device using the Peltier effect.

  As a method of improving the heat dissipation characteristics of the heat dissipation surface, it is ideal to join a water-cooled heat sink with high heat dissipation characteristics, but since the water-cooling structure is complicated and large, generally fins or fans, It is used by adhering a heat exchanger such as a fan with fins to the heat dissipation surface. In addition to using a heat exchanger on the cooling surface, not only can it be used for both cooling and heating, but air can be used to cool or dissipate the fins by air. It can be used as a simple air conditioner.

Here, as shown in Patent Document 1, as the fins of the heat exchange device using the thermoelectric module that can be used for both cooling and heat dissipation, it is easy to arrange the members constituting the fins evenly. Has been used. Patent Document 2 discloses a thermoelectric module in which a heat exchange fin is directly joined to a thermoelectric element in order to improve heat dissipation characteristics.
JP 2003-332642 A JP 2002-84007 A

  However, a heat exchange device using a thermoelectric module that has heat exchange fins used for both cooling and heating has a coefficient of performance (COP) indicated by the ratio of power consumption to cooling performance (cooling performance / power consumption). It is still 1 or less in the practical range, and the efficiency is remarkably worse than that of COPs 3 to 4 of the compression refrigerator, and it is used only for limited applications. Also, in recent years, the range of temperature and humidity that guarantees performance, such as cooling of automobile seats, has expanded, and applications in harsh environments have expanded, requiring high durability characteristics and reliability at the same time as improving performance. ing.

  In such a viewpoint, in the heat exchange device provided with heat exchange fins spaced apart at equal intervals, the flow of the heat exchange medium (mainly air) is not considered, and heat exchange is performed in the heat exchange device. In addition, there is a problem that the heat exchange efficiency is low and the durability is inferior when, for example, the reversal of the positive and negative of the applied voltage is repeated. Furthermore, in places where the humidity is high, such as in an automobile, condensation occurs on the cooling side, so that the heat exchange efficiency decreases. Moreover, in the structure like patent document 2 mentioned above, there exists a possibility that the elements of a thermoelectric module may short-circuit.

  Therefore, an object of the present invention is to obtain a heat exchange device using a thermoelectric module that has high heat exchange characteristics and is excellent in long-term reliability in a high-temperature and high-humidity environment.

  The heat exchange device of the present invention for solving the above-described problem has a pair of opposing support substrates, a plurality of thermoelectric elements are arranged between one main surface of these support substrates, and the adjacent thermoelectric elements are connected to each other. In the heat exchanging device, comprising: a thermoelectric module electrically connected by an electrode; and a fin disposed on the other main surface side of at least one of the pair of support substrates, A plurality of heat exchanging plates standing in a direction substantially perpendicular to the main surface of the support substrate and arranged substantially parallel to each other, and two adjacent heat exchange plates disposed near the center of the arrangement direction of the heat exchanging plates; The interval between the heat exchange plates is smaller than the interval between two adjacent heat exchange plates arranged near both ends in the arrangement direction. It is preferable that the interval between the two adjacent heat exchange plates in the present invention gradually increases from the vicinity of the center in the arrangement direction to the vicinity of both ends.

  The heat exchange device of the present invention has a pair of opposed support substrates, a plurality of thermoelectric elements are arranged between one main surface of these support substrates, and the adjacent thermoelectric elements are electrically connected by electrodes. In the heat exchanging device comprising a connected thermoelectric module and a fin disposed on the other main surface side of at least one of the pair of support substrates, a plurality of the fins through which a heat exchange medium passes. Among these channels, the cross-sectional area of the channel near the center may be smaller than the channels near both ends. In the present invention, it is preferable that the cross-sectional areas of the plurality of channels gradually increase from the channel near the center toward the channels at both ends.

  In the present invention, the surface of the fin is preferably subjected to water repellent treatment, and the fin is more preferably a corrugated fin.

  According to the heat exchanging device of the present invention, the fin has a plurality of heat exchanging plates standing in a direction substantially perpendicular to the main surface of the support substrate and arranged substantially parallel to each other, Since the interval between two adjacent heat exchange plates arranged near the center in the arrangement direction is smaller than the interval between two adjacent heat exchange plates arranged near both ends in the arrangement direction, the heat exchange device Variations in the flow rate of the heat exchange medium being sent can be suppressed and the velocity distribution can be made more uniform, so variations in heat exchange efficiency can be suppressed, and as a result, the durability of the heat exchange device can be reduced. Can be improved.

  Further, when the interval between the two adjacent heat exchange plates gradually increases from the vicinity of the center in the arrangement direction to the vicinity of both ends, the gap is generated in the thermoelectric module even when the reversal of the positive / negative of the applied voltage is repeated. The difference in thermal expansion becomes gradual and durability is further improved.

  According to another heat exchange device of the present invention, the fin has a plurality of flow paths through which the heat exchange medium passes, and among these flow paths, the cross-sectional area of the flow path near the center is larger than the flow paths near both ends. Therefore, variation in the flow rate of the heat exchange medium sent to the heat exchange device can be suppressed, and the velocity distribution can be made more uniform, so that variation in heat exchange efficiency can be suppressed. The durability of the heat exchange device can be improved.

  In addition, when the cross-sectional area of the plurality of flow paths gradually increases from the flow path near the center toward the flow paths at both ends, the thermal expansion that occurs in the thermoelectric module even when the applied voltage is repeatedly reversed. The difference becomes milder and durability is improved.

  Further, it is further desirable that the heat exchange fin is subjected to water repellent treatment. This is because, for example, under high-temperature and high-humidity conditions such as automotive applications, condensation occurs on the cooling fin surface and a phenomenon that hinders the heat exchange effect occurs. It is possible to prevent condensation from staying. Moreover, since moisture due to condensation does not occur in the heat exchange device, leakage in the thermoelectric module can be prevented.

  Furthermore, by using an integrated corrugated fin for the heat exchange fins, the surface area of the flow path formed by the fins can be increased, and more uniform heat exchange can be achieved, providing both heat exchange efficiency and durability. Gave good results.

  As described above, according to the present invention, a heat exchange device using a thermoelectric module having excellent heat exchange characteristics and durability characteristics can be obtained, and heat can be obtained by using the heat exchange device of the present invention for a cold storage room, an air conditioner, or the like. The exchange efficiency is high, and it can be used for a long time even in a high temperature and high humidity environment.

  FIG. 2 is a cross-sectional view showing a heat exchange device according to an embodiment of the present invention. FIG. 3 is a perspective view showing a heat exchange device according to an embodiment of the present invention.

  As shown in FIG. 2, the heat exchanging device according to the present embodiment includes a pair of support substrates 1 including support substrates 1a and 1b, and one main surface side of each of the support substrate 1a and the support substrate 1b. And the fins 7, 7 provided on the other main surface side of each of the support substrate 1 a and the support substrate 1 b, and the thermoelectric elements 3 including a plurality of N-type thermoelectric elements 3 a and P-type thermoelectric elements 3 b arranged between the surfaces. And. A plurality of electrodes 2 that electrically connect adjacent N-type thermoelectric elements 3a and P-type thermoelectric elements 3b are formed on one main surface of each of the support substrates 1a and 1b. The support substrates 1 a and 1 b are composed of a metal plate 8 and an insulating layer 5. Fins 7 are fixed to the metal plate 8 by connecting members 6a. The electrode 2 and the thermoelectric element 3 are fixed by a connecting member 6 b, and each thermoelectric element 3 is electrically connected in series by the electrode 2. The insulating layer 5 is intended to electrically insulate the metal plate 8 and the electrode 2 from each other.

  In the heat exchange device having such a structure, the heat absorption or heat dissipation generated in the electrode 2 is transferred to the fin 7 and cooled or radiated by the fin 7. For example, when air is allowed to flow through the fins 7 and air-cooled, depending on the situation, cooled or heated air is generated and can be used as an air conditioner.

  The thickness of the metal plate 8 is 0.5 mm or less, preferably 0.1 to 0.3 mm, from the viewpoint of relaxing thermal stress. If the thickness exceeds 0.5 mm, the rigidity becomes high and the film cannot be easily deformed, causing stress concentration, which may reduce repeated durability characteristics. The material of the metal plate 8 is preferably copper, aluminum having high thermal conductivity, or an alloy containing them as a main component.

  The thickness of the electrode 2 is preferably 0.1 mm or more from the viewpoint of the current value supplied to the thermoelectric element 3. When the thickness is 0.1 mm or less, heat is generated due to the influence of the current value flowing through the thermoelectric module, which may reduce the performance of the heat exchange device. The material of the electrode 2 is preferably copper, aluminum having a low electrical resistivity, or an alloy containing them as a main component.

  The connecting members 6a and 6b are not particularly limited as long as they are metals, and may be brazing materials such as Ag, Cu, Zn, Ti, and Al, but are preferably solder. The reason why solder is preferable is as follows. That is, as described above, since the thermoelectric module generates a large temperature difference between both surfaces, thermal stress is likely to occur. Since this thermal stress tends to concentrate especially on the connecting portion, it is possible to greatly enhance the durability against repeated cold heat by using solder that is easily deformed in the connecting portion. In particular, by using a solder whose main component is at least one selected from the group consisting of Sn, Bi, Ag, Cu, Au, Zn, and In, it is possible to increase joint strength and durability. The specific solder composition is 42Sn-58Bi, 95Sn-5Sb, 96.5Sn-3.5Ag, 48Sn-52In, 96.5Sn-3Ag-0.5Cu, 80Au-20Sn, 91Sn-9Zn in mass% ratio. Etc. can be used suitably. Moreover, the influence on the environment can be reduced by using Pb-free solder, and deterioration of durability due to Pb ions can be suppressed.

  The thickness of the connecting members 6a and 6b is 5 μm or more, preferably 10 μm or more, more preferably 10 to 30 μm. Thereby, it is possible to prevent adhesion failure from occurring at the interface between the electrode 2 and the connecting member 6b, the heat exchanger 7 and the connecting member 6a, and to reduce the thermal resistance. When this thickness is less than 5 μm, a non-adhered space is likely to be generated, which may increase thermal resistance and at the same time reduce adhesiveness. In particular, in such a poorly contacted region, stress is likely to concentrate, and there is a risk that durability during repeated use may deteriorate. Furthermore, since the connecting member 6b is easily affected by the high temperature heat accompanying the heat generation of the thermoelectric element 3, the melting temperature of the connecting member 6b is preferably higher than the melting temperature of the connecting member 6a.

  The support substrate 1 forms an insulating layer 5 on the surface opposite to the surface connected to the heat exchanger 7 by the connecting member 8, and this insulating layer 5 needs high insulation and a certain degree of flexibility. It is desirable that it is made of resin. By using at least one of polyimide, polyamide, polyamideimide, epoxy, and polyethylene terephthalate (PET) as the insulating layer 5, chemically stable characteristics can be obtained even in the above-described high temperature and high humidity environment. The thickness of the insulating layer 5 is preferably 0.01 mm or more for maintaining insulation, more preferably 0.02 mm or more, still more preferably 0.03 mm or more, and particularly preferably 0.03 to 0.1 mm. There should be. As a method for forming the insulating layer 5 on the surface of the support substrate 1, a resin material is uniformly formed on the metal plate 8 by an existing method such as a doctor blade method or a screen printing method, and then the electrode substrate 2 is overlaid. For example, a method by thermocompression bonding in which stress is applied while applying a temperature of about 200 to 400 ° C. can be exemplified.

  It is preferable that the insulating layer 5 contains a highly thermally conductive filler such as an inorganic oxide or an inorganic nitride in order to increase the thermal conductivity of the insulating layer and reduce the thermal resistance. The addition rate of a filler is 30 volume% or more, Preferably it is 30-70 volume%. The filler has a particle size of 1 μm or more, preferably about 10 to 100 μm, and is preferably scaly particles in order to increase the thermal conductivity. Examples of the filler include oxides such as alumina, zinc oxide, and silicon oxide, and nitrides such as boron nitride, aluminum nitride, and silicon nitride.

  The fin 7 is not particularly limited as long as it has a structure for radiating heat, and examples thereof include a structure having a space through which air flows as shown in FIG. 2 and a structure having many radiating pins. Raised. Furthermore, if it has a fan, air cooling can be performed simultaneously. Further, in order to increase the surface area of the fin 7, the fin surface may be provided with irregularities. However, in order to increase the pressure loss and increase the size of the air blower, the waveform (wave) as shown in FIG. 3 is applied. Corrugated fins are desirable.

  The material constituting the fin 7 is preferably copper or aluminum in order to obtain high thermal conductivity and enhance heat exchange characteristics. In particular, the metal plate 8 and the fin 7 are both made of the same material and have the same thermal expansion coefficient, so that the thermal stress during connection can be reduced. Furthermore, it is preferable to use copper for both in order to facilitate solder joining. When aluminum is used, solder bonding is possible by forming a plating layer such as Sn on the surface.

  In the present invention, as shown in FIG. 4, the fins 7 are arranged on the metal plate 8 on the surface of the thermoelectric module so that the cross-sectional area of the flow path that needs to increase the heat exchange efficiency is larger than the other flow paths. This is very important. With the arrangement of the fins, heat from the thermothermal module can be efficiently exchanged with the heat exchange medium via the fins. This is because, by equalizing the flow rate of the heat exchange medium flowing in the flow path formed by the fins 7, the heat that the thermoelectric element 3 radiates and absorbs heat can be evenly transmitted from the fins 7 to the heat exchange medium, For example, even when the applied voltage is repeatedly reversed between positive and negative, the difference in thermal expansion generated in the thermoelectric module becomes gradual, and the durability is further improved.

  Usually, the heat exchange medium such as air sent to the fins 7 through the pipe has the fastest flow rate in the central part and slowly slows down to the wall surface. It is desirable that the cross-sectional area is smaller than the flow path near both ends. Further, in consideration of the flow distribution of the heat exchange medium, it is more desirable that the cross-sectional area of the flow path gradually increases from the central flow path toward the flow paths at both ends.

  Here, in the present invention, the “cross-sectional area of the flow path” means that the flow path is configured in a cross section perpendicular to the support substrate and perpendicular to the flow path (perpendicular to the traveling direction of the fluid flowing in the flow path). It refers to the area of a region surrounded by members (heat exchange plate, main surface of support substrate, etc.). For example, when a part of the flow path is open, it refers to the area of a region surrounded by a straight line connecting both ends of the opening and a member constituting the flow path.

  For the same reason as described above, the fin 7 stands up in a direction substantially perpendicular to the main surfaces of the support substrates 1a and 1b and is arranged in a plurality of heat exchange plates 7a, 7a,. , 7a, and an interval c1 between two adjacent heat exchange plates disposed at the center in the arrangement direction of the heat exchange plate 7a is equal to two adjacent heat exchange plates 7a disposed at both ends in the arrangement direction. You may make it become smaller than the space | interval c2. Further, it is more preferable that the distance between the two adjacent heat exchange plates 7a, 7a gradually increases from the vicinity of the center in the arrangement direction toward the vicinity of both ends.

  Further, it is desirable to provide a water repellent coating mainly composed of fluorine and silicon on the surface of the fin 7. A commercially available fluorine or organic solvent containing silicon is applied as a thin film by a method such as spraying or dipping and dried to form a film. Due to this water-repellent coating, for example, when a heat exchange device such as the present invention is operated in high temperature and high humidity such as in a car, condensation occurs on the cooling fins. In the case of a heat exchange medium such as air, the fins on which condensation has occurred are deteriorated in heat transfer due to the water film on the surface of the fins, thereby reducing the performance of the heat exchange device itself. In addition, when water droplets due to this condensation enter the thermoelectric module, an electrical short circuit may occur, leading to electric leakage. In order to suppress the dew condensation, circuit means that frequently repeats the reversal of the voltage applied to the thermoelectric element 3 to always dry the fins is also effective.

  Further, the fin 7 is preferably a corrugated fin. By using corrugated fins, the surface area of the flow path formed by the fins can be increased, and more uniform heat exchange can be achieved, resulting in both good heat exchange efficiency and durability. Furthermore, since the fins are integrated, the temperature of the entire fin 7 is easily equalized, and the thermal stress at the interface between the electrode 2 and the connecting member 6b, which is weak in strength, and the heat exchanger 7 and the connecting member 6a is weakened. For example, in the case where the reversal of the positive and negative of the applied voltage is repeated, the durability is improved.

  The fin 7 is desirably 0.3 mm or less in thickness in order to reduce the heat capacity of the heat exchange device itself. If the thickness is 0.3 mm or more, it is difficult to form a complicated bent shape, and it is difficult to form an integrated corrugated fin 7. Furthermore, as shown in FIG. 4, when the fin 7 is manufactured and processed, the length occupied by the bending processing length b is 15 to 62% with respect to the bonding length a in the solder joint portion of the fin 7. Things are even more desirable. If it is 15% or less, when solder is used for the joining member 6a, the joining member 6a does not crawl up to the side surface of the fin 7, resulting in poor heat transfer from the metal plate 8 to the joining member 6a. As a result, the performance is degraded. On the other hand, if it is 62% or more, heat transfer from the lower part of the fins 7 is reduced, resulting in a decrease in performance of the heat exchange device.

  Next, a method for manufacturing the thermoelectric module according to the present embodiment will be described. First, a thermoelectric element made of a thermoelectric material manufactured by a known technique is prepared. As this thermoelectric material, bismuth and tellurium materials are preferable in that high thermoelectric characteristics can be obtained. Thermoelectric materials include melted and solidified materials once melted, sintered materials obtained by pulverizing alloy powders and sintered by hot pressing, single crystal materials solidified in one direction by the Bridgeman method, etc. Although it can be used, single crystal materials are particularly preferable because of their high performance.

  Using these thermoelectric materials, a thermoelectric element 3 is produced by a known technique. As a method for manufacturing a thermoelectric element, there is a method in which an ingot is sliced, a reaction preventing layer is formed by plating, vapor deposition, thermal spraying, or the like with nickel, and then dicing is performed to obtain an element. In addition, it is costly to coat a single crystal rod with an environment-resistant epoxy resin or other plating-resistant resin, and then cut and deposit nickel on the cut surface only by electrolytic plating or electroless plating. It is preferable for further preventing corrosion due to moisture. Further, it is preferable to dispose a Sn or Au layer on the nickel layer in order to improve the connectivity with the connecting member.

  Next, the support substrate 1 described above is prepared. In the present invention, the insulating layer 5 in the support substrate 1 is preferably made of resin. As a method for forming the metal plate 8 on one surface of the resin layer 5 and the electrode 2 on the other surface of the resin layer 5, any known method may be used, but it is desirable because adhesion by thermocompression bonding is easy. In order to increase the adhesive strength, a method of coating an adhesive may be applied. After the metal plate 8 and the electrode 2 are bonded to these surfaces, one or both surfaces are subjected to pattern etching by a photoresist method, so that the support substrate 1 in which the electrodes 2 are wired with metal is obtained. The metal for pattern etching is preferably aluminum or copper, and copper is particularly preferable because of its high thermal conductivity and electrical conductivity.

  Next, the thermoelectric element 3 and the electrode 2 on the support substrate 1 are joined by the joining member 6b. Solder is arranged on the surface of the electrode 2. There are several methods for arranging the solder, but it is easy to arrange them by screen printing. Next, the thermoelectric element 3 is arranged on the surface of the electrode 2 on which the solder is arranged. The thermoelectric element 3 has two types of elements, N-type and P-type, arranged in a staggered pattern. Any known technique may be used as the joining method, but the N-type and the P-type are separately oscillated and arranged by a transfer method in which they are transferred to a jig that has been processed into an array hole, and then transferred onto an insulating substrate. The arrangement method is simple and preferable. After the thermoelectric elements 3 are arranged, the opposite insulating substrate on which the solder is arranged is placed on the upper surface. The insulating substrate sandwiching the arranged thermoelectric elements is soldered by a known technique. As a soldering method, any method such as heating by a reflow furnace or a heater may be used. However, when a resin is used for the insulating layer 5 in the support substrate 1, heating is performed while applying stress to the upper and lower surfaces. It is preferable for increasing the ratio.

  Next, the metal plate 8 and the fins 7 attached to both surfaces of the obtained thermoelectric element 3 are connected by a connecting member 6a. The shape and material of the fin 7 to be used varies depending on its application. However, when used as an air conditioner mainly for cooling, a copper fin is preferable. Especially when used in air cooling, the area in contact with air is increased. Corrugated fins made in a wavy shape are desirable. It is also common to improve heat dissipation and improve cooling characteristics by making the heat dissipation side fins 7 have a larger heat exchange amount.

  When connecting to the connecting member 6a using solder, after printing the solder on the metal plates 8 on both sides, the fins 7 are arranged on both sides, and heating is performed while applying stress to both sides as in the case where the thermoelectric element 3 is joined. Can be connected. At this time, it is possible to adjust the thickness, heat resistance, and adhesion of the connected state depending on the type and amount of solder used for printing. By making the surface of the metal to be connected to have a rough surface, the anchor effect is generated and the adhesion can be improved. Finally, the lead wire 4 for supplying current to the thermoelectric module to which the fin 7 is connected is joined with a soldering iron or the like, and the surface of the fin 7 is treated with a water repellent coating by a method such as spraying. The heat exchange device of the invention is obtained.

  The heat exchange device obtained as described above can transmit the heat from the thermoelectric module uniformly from the fins 7 to the heat exchange medium such as air, so that the generation of thermal stress in the thermoelectric module is small. Since the condensation on the cooling side is discharged from the heat exchange device by the water repellent coating, it has high durability characteristics even in applications where cooling and heating are used alternately for a long period of time.

  Examples of the present invention are shown below.

  First, a thermoelectric element having a size of 1.5 mm square and a support substrate having the size shown in Table 1 and a size of 40 mm × 20 mm were prepared. The support substrate was formed by forming an insulating layer in which 50 vol% of alumina particles having a particle diameter of 0.001 mm were mixed with epoxy resin between 0.1 mm copper plates by the doctor blade method and heated under conditions of 300 ° C. and 0.5 MPakg / mm 2. Created by pressing. Then, one side was pattern-etched to form an electrode pattern. Then, the thermoelectric element was joined to the electrode with 95Sn-5Sb solder to produce a thermoelectric module.

  Next, fins (a) to (c) having 19 flow paths (heat exchange plate intervals) composed of 19 blades (heat exchange plates) as shown in Table 2 are prepared (see Table 2). , 42Sn-58Bi solder. The corrugated shape was processed into a wave shape having a height of 0.2 mm and a width of 5 mm. For the water repellent treatment of the fins, a fluororesin coating was applied by spray treatment.

  The “fin interval No.” in Table 2 is the “fin interval No.” between two adjacent heat exchange plates located on the leftmost when the heat exchange device is viewed in the arrangement state shown in FIG. 1 ”, and in order of No. Numbers up to 18 are assigned.

(An endurance test)
While supplying 50W electric power to the obtained heat exchanger device and generating a temperature difference, 4 m / sec of wind was radiated to both fins on the cooling surface under the conditions of 25% temperature and 40% humidity. The cooling capacity was calculated by setting the difference between the inlet temperature and the outlet temperature of the cooling side wind as the temperature difference ΔT1. At the same time, the endurance test in which energization was reversed every other minute was performed for 10,000 cycles, and the change in the resistance value of the thermoelectric module after the endurance test was calculated. Furthermore, in an environment where the temperature is 25 ° C. and humidity is 80%, both fins are radiated with 4 m / sec of wind, applied to the cooling surface, and energized for 100 hours. The difference between the inlet temperature and the outlet temperature was measured as a temperature difference ΔT1, and a difference ΔT2 before and after the test was calculated. The results are shown in Table 1.

  In Table 1, the sample NO. No. 2 is a sample No. 2 using fins with equally spaced channels. 1, the cooling effect (ΔT1) is large, and the resistance change of the thermoelectric module after the reverse energization cycle test is small. Sample No. using fins in which the interval of the flow path is gradually increased from the center. In No. 3, the resistance change of the thermoelectric module after the inversion energization cycle test was further small, and a good result was obtained.

  In addition, the sample No. 1 subjected to the water repellent treatment. Sample Nos. 4 to 9 were not subjected to water repellent treatment. Compared to 1-3, the difference (ΔT2) in ΔT1 before and after continuous energization under high humidity was small, and even better durability was confirmed even under high humidity.

  Furthermore, in the case where the fin is a corrugated fin, the sample No. using a fin not having a corrugated shape is used. Compared with 2 to 9, ΔT1 is large, and the cooling effect is large. Also in the corrugated fins, the sample Nos. 1 and 2 in which the central portion of the flow path of the fin 7 is narrowed and the end portion is widened. No. 8 is a sample No. 8 using fins with equally spaced channels. 7, the cooling effect (ΔT1) is large, and the resistance change of the thermoelectric module after the inversion energization cycle test is small. Sample No. using fins in which the interval between the channels is gradually reduced from the central portion. In No. 8, the resistance change of the thermoelectric module after the inversion energization cycle test was further small, and a good result was obtained.

  As described above, No. which is within the scope of the present invention. Sample Nos. 2 to 9 are outside the scope of the present invention. Compared to 1, the cooling temperature is low, the resistance change rate after the reverse energization cycle test is small, and the change in temperature difference after the moisture resistance test is also small. It was confirmed that

It is a perspective view which shows the heat exchange apparatus using the conventional Peltier effect. It is sectional drawing which shows the heat exchange apparatus concerning one Embodiment of this invention. It is a perspective view which shows the heat exchange apparatus concerning one Embodiment of this invention. It is an expanded sectional view of the fin joint part of the heat exchange device concerning one embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Support substrate 2 Wiring conductor 3 Thermoelectric element 3a N type thermoelectric element 3b P type thermoelectric element 4 External connection terminal 5 Insulating layer
6 connecting member 6a connecting member 6b connecting member 7 fin 7a heat exchange plate 8 metal plate

Claims (6)

A thermoelectric module having a pair of opposing support substrates, a plurality of thermoelectric elements arranged between one main surface of these support substrates, and electrically connecting adjacent thermoelectric elements with electrodes, and the pair of support Among the substrates, in the heat exchange device including fins disposed on the other main surface side of at least one support substrate, the fins stand up in a direction substantially perpendicular to the main surface of the support substrate. It has a plurality of heat exchange plates arranged substantially parallel to each other, and an interval between two adjacent heat exchange plates arranged near the center in the arrangement direction of the heat exchange plates is arranged near both ends in the arrangement direction. A heat exchanging device characterized in that it is smaller than the interval between two adjacent heat exchanging plates. The heat exchanger according to claim 2, wherein an interval between the two adjacent heat exchange plates gradually increases from near the center in the arrangement direction toward both ends. A thermoelectric module having a pair of opposing support substrates, a plurality of thermoelectric elements arranged between one main surface of these support substrates, and electrically connecting adjacent thermoelectric elements with electrodes, and the pair of support Among the substrates, in the heat exchange device provided with fins disposed on the other main surface side of at least one of the support substrates, the fin has a plurality of flow paths through which the heat exchange medium passes, and these flow A heat exchange device characterized in that a cross-sectional area of a channel near the center is smaller than a channel near both ends. 4. The heat exchange device according to claim 3, wherein a cross-sectional area of the plurality of flow paths gradually increases from a flow path near the center toward a flow path at both ends. The heat exchange apparatus according to any one of claims 1 to 4, wherein a surface of the fin is subjected to a water repellent treatment. The heat exchange apparatus according to claim 1, wherein the fin is a corrugated fin.

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