TWI419385B - Heat exchange unit - Google Patents

Description

Heat exchange unit

The present invention relates to a heat exchange unit including a thermoelectric module in which different types of thermoelectric elements are alternately aligned and electrically connected in series between the endothermic electrode and the heat dissipating electrode.

The present application claims priority to Japanese Patent Application No. 2009-18498, the disclosure of which is incorporated herein by reference.

Conventionally, a thermoelectric module has been developed and designed such that thermoelectric elements composed of a P-type semiconductor and an N-type semiconductor are alternately aligned and connected in series, and are held between a heat absorbing electrode and a heat dissipating electrode via a metal such as a solder metal. Various documents disclose a heat exchange unit in which a heat exchanger is bonded to a heat absorbing electrode or a heat sink electrode of a thermoelectric module to improve heat dissipation efficiency.

Patent Document 1: Japanese Unexamined Patent Application Publication No. 2003-332642

Patent Document 2: Japanese Unexamined Patent Application Publication No. 2006-234362

Patent Document 1 discloses a thermoelectric converter unit, that is, the heat exchange unit 40 shown in FIG. In the heat exchange unit 40, an insulating layer 42 composed of alumite (or anodized aluminum) is formed on a heat exchange member (heat sink) 41 composed of an aluminum plate; the metal plating layer 43 is in the same pair as the metal electrode 44. The quasi-pattern is integrally formed on the insulating layer 42; and the metal electrode 44 is bonded to the metal plating layer 43. The P-type thermoelectric element 45a and the N-type thermoelectric element 45b are alternately aligned and electrically connected in series between the "lower" metal electrode 44 and the "upper" metal electrode 46. The thermoelectric module 40a is composed of thermoelectric elements 45a and 45b, a lower metal electrode 44, and an upper metal electrode 46.

Patent Document 2 discloses a heat exchanger, that is, the heat exchange unit 50 shown in Fig. 15. The heat exchange unit 50 includes a thermoelectric converter module (or thermoelectric module) 50a interposed between the heat dissipating member (or heat sink) 51 and the heat absorbing member (or heat sink) 52, wherein the plurality of thermoelectric elements 55 are inserted into the heat dissipating electrode 53 is between the heat absorbing electrode 54. Here, the resin 56a, the metal foil 56b, and the solder 56c are inserted between the heat radiating member 51 and the heat radiating electrode 53, and the resin 57a and the grease 57b are inserted between the heat absorbing member 52 and the heat absorbing electrode 54. The resin 56a is deposited on the surface of the heat dissipating member 51, and the resin 57a is deposited on the surface of the heat absorbing member 52. During the deposition, the resins 56a and 57a are softened to partially penetrate into the cavities and cracks formed on the surfaces of the heat radiating member 51 and the heat absorbing member 52 and then hardened.

Recently, a filler composed of alumina powder and aluminum nitride has been used and uniformly dispersed into an insulating resin layer (initially having poor thermal conductivity) in order to improve thermal conductivity. The design of the heat exchange unit 40 disclosed in Patent Document 1 does not take into consideration the surface roughness of the heat exchanger 41, the thickness of the insulating layer 42, and the filler added to the insulating layer 42 (serving as an insulating resin layer). Even when the heat exchanger 41 is composed of an aluminum alloy whose surface is coated with an anodic oxide coating, it is difficult to improve the adhesion between the heat exchanger 41 and the insulating layer 42 and it is difficult to reduce the thermal resistance between the two.

The surfaces of the heat radiating member 51 and the heat absorbing member 52 are roughened so that the resins 56a and 57a can easily penetrate into the cavity and the crack, wherein cracks and cracks may occur in the insulating resin layer, and the filler is dispersed into the insulating resin layer. To improve the thermal conductivity. This is because the dispersion of the "hard" filler causes small cracks and cracks to be formed in the insulating resin layer due to the pressurization during the thermocompression. This disadvantage is regenerated even when the insulating resin layer is hardened by applying a varnish resin.

An object of the present invention is to provide a heat exchange unit in which a heat exchanger is controlled in terms of surface roughness so as to prevent cracks and cracks from being formed in an insulating resin layer, thereby improving adhesion between the heat exchanger and the insulating resin layer. . The heat exchange unit has high reliability due to the reduced thermal resistance between the heat exchanger and the insulating resin layer.

A heat exchange unit is composed of a heat exchanger and a thermoelectric module. The thermoelectric module includes an upper electrode, a lower electrode and a plurality of thermoelectric elements. The thermoelectric elements are inserted and electrically connected in series between the upper electrode and the lower electrode. The heat exchanger is attached to the surface of the upper electrode and/or the surface of the lower electrode via an insulating layer. The surface roughness of the heat exchanger adjacent to the insulating layer is controlled to be less than 4.7 μm. For example, here, the surface roughness Ra is estimated according to Japanese Industrial Standards (ie, JIS B0601).

According to the measurement results of the test examples regarding the heat exchange unit, the heat exchanger has a surface roughness Ra equal to or less than 4.7 μm (where Ra) 4.7 μm) and having a surface roughness Ra equal to or greater than 0.1 μm (where Ra In the case of 0.1 μm), it is possible to prevent cracks and cracks from being formed at the interface between the insulating layer and the heat exchanger, and it is possible to uniformly form an insulating layer having a specified thickness. Even when the thickness of the insulating layer is less than 100 μm, it is possible to prevent cracks and cracks from being formed in the insulating layer. This makes it possible to further reduce the thickness of the insulating layer and thereby reduce the thermal resistance, thus improving the heat absorption/heat dissipation performance.

The heat exchanger is preferably composed of aluminum or an aluminum alloy having high thermal conductivity in view of manufacturability and manufacturing cost. The insulating layer is preferably composed of a single insulating resin layer having a high thermal conductivity or a composite layer in which an insulating resin layer is laminated on an alumite layer. The filler is preferably dispersed in an insulating resin or a varnish insulating resin for use in the insulating layer. The filler is preferably composed of alumina powder, aluminum nitride powder, magnesium oxide powder or tantalum carbide powder. The insulating resin is preferably selected from the group consisting of a polyimide resin or an epoxy resin. In this regard, the insulating resin is formed into a sheet shape via curling, or is painted and cured.

Due to the optimized surface roughness of the heat exchanger, it is possible to prevent cracks and cracks from being formed in the insulating layer, possibly improving the adhesion between the heat exchanger and the insulating layer, and possibly reducing the thermal resistance and thereby improving Heat absorption/heat dissipation performance and reliability of the heat exchange unit.

These and other objects, aspects and embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

The invention will be described in more detail by way of example with reference to the accompanying drawings.

1. First embodiment

A heat exchange unit 10 according to a first embodiment of the present invention will be described with reference to Figs. 1A to 1C. As shown in FIG. 1C, the heat exchange unit 10 is composed of a first heat exchanger (serving as a heat dissipating or heat absorbing air cooling fin) 11, and a surface formed on the surface of the first heat exchanger 11. The insulating layer 12, a lower electrode disposed on the insulating layer 12 (serving as a heat dissipating or heat absorbing electrode) 13, a plurality of thermoelectric elements 14 coupled to the lower electrode 13, and an upper electrode coupled to the thermoelectric elements 14 ( It functions as a heat dissipating or heat absorbing electrode 15 , a second heat exchanger (serving as a heat dissipating or heat absorbing air cooling fin) 16 , and an insulating layer 17 formed on the surface of the second heat exchanger 16 . A pair of terminals (none of which are shown) connected to a pair of leads are formed on one end of the lower electrode 13.

A thermoelectric module M (see FIG. 3) is composed of the thermoelectric elements 14, which are electrically connected in series between the lower electrode 13 and the upper electrode 15 via a bonding metal such as solder.

The first heat exchanger 11 and the second heat exchanger 16 are each composed of aluminum or aluminum alloy having high thermal conductivity, wherein (the surface adjacent to the insulating layer 12) the surface of the first heat exchanger 11 and (adjacent to the insulating layer 17) The surfaces of the second heat exchanger 16 are each trimmed to have a surface roughness Ra of 5 μm or less. In addition, a plurality of heat radiating fins 11a protrude downward from the first heat exchanger 11, and a plurality of heat radiating fins 16a protrude upward from the second heat exchanger 16.

Each of the insulating layers 12 and 17 is composed of a polyimide resin, an epoxy resin or an alumite, and the insulating layers have a thickness of 10 μm to 100 μm. Preferably, a filler composed of alumina (Al ₂ O ₃ ), aluminum nitride (AlN), magnesium oxide (MgO) or tantalum carbide (SiC) having an average particle diameter of 15 μm or less is dispersed to the polyruthenium. An insulating layer 12 and 17 composed of an amine resin or an epoxy resin improves the thermal conductivity. Further, it is preferred to laminate a polyimine resin or an epoxy resin in which a filler is dispersed on the insulating layers 12 and 17 composed of alumite.

When the lower electrode 13 functions as a heat radiating electrode, the upper electrode 15 functions as a heat absorbing electrode, or when the lower electrode 13 functions as a heat absorbing electrode, the upper electrode 15 functions as a heat radiating electrode. The lower electrode 13 and the upper electrode 15 are each composed of a copper thin film or a copper alloy thin film having a thickness of 70 μm to 200 μm. The lower electrode 13 has the alignment pattern shown in FIG. 2A, and the upper electrode 15 has the alignment pattern shown in FIG. 2B. Each section of the lower electrode 13 is formed into a rectangular shape having a length of 3 mm and a short length of 1.8 mm. Similarly, each section of the upper electrode 15 is formed into a rectangular shape having a length of 3 mm and a short length of 1.8 mm.

The thermoelectric elements 14 composed of a P-type semiconductor and an N-type semiconductor are electrically connected in series between the lower electrode 13 and the upper electrode 15 in such a manner that the P-type semiconductor and the N-type semiconductor are alternately aligned. The thermoelectric elements 14 are soldered to the lower electrode 13 and the upper electrode 15 via a SnSb alloy, an AuSn alloy, or a SnAgCu alloy. The distal ends of the thermoelectric elements 14 are nickel plated so that the thermoelectric elements 14 can be easily soldered to the lower electrode 13 and the upper electrode 15.

The thermoelectric elements 14 are preferably composed of a Bi-Te sintered thermoelectric material having high thermoelectric efficiency at room temperature. Specifically, a P-type semiconductor composed of a ternary compound of Bi-Sb-Te and an N-type semiconductor composed of a quaternary compound of Bi-Sb-Te-Se are preferably used. In the current embodiment, the P-type semiconductor is composed of Bi _0.5 Sb _1.5 Te ₃ and the N-type semiconductor is composed of Bi _1.9 Sb _0.1 Te _2.6 Se _0.4 , wherein the semiconductors are subjected to liquid quenching to produce a foil powder, The foil powder is then hot pressed to form a block which is then cut into small pieces each having a specified size of 1.35 mm long, 1.35 mm wide and 1.5 mm high.

(a) Manufacturing of heat exchange unit 10

The heat exchange unit 10 is manufactured by the following procedure.

First, a first heat exchanger 11 (serving as a heat-dissipating air-cooling fin) is prepared such that an adhesive insulating layer 12 is formed on one surface of the heat exchanger, and heat-dissipating fins 11a are formed on opposite sides thereof. on. Similarly, a second heat exchanger 16 (serving as an endothermic air-cooling fin) is prepared such that an adhesive insulating layer 17 is formed on one side of the heat exchanger, and heat-dissipating fins 16a are formed on the opposite side. On the surface. Further, the lower electrode 13 (serving as a heat radiating electrode) and the upper electrode 15 (serving as a heat absorbing electrode) are prepared in advance. Further, the thermoelectric elements 14 composed of a P-type semiconductor and an N-type semiconductor are prepared in advance.

The first heat exchanger 11 and the second heat exchanger 16 are each composed of aluminum or an aluminum alloy having a high thermal conductivity. The surface of the first heat exchanger 11 (adjacent to the insulating layer 12) and the surface of the second heat exchanger 16 (adjacent to the insulating layer 17) are each trimmed to have a surface roughness Ra of 5 μm or less. The insulating layers 12 and 17 are formed by dispersing a powder filler composed of Al ₂ O ₃ , AlN, MgO or SiC into an adhesive polyimide or epoxy layer. Alternatively, the insulating layers are formed using a composite layer in which a polyimine resin layer or an epoxy layer in which a filler is dispersed is formed on the alumite layer. Here, the insulating layers 12 and 17 are formed by crimping the material of the sheet shape. Alternatively, the varnish is applied to a sheet-shaped material, which is then cured to form insulating layers 12 and 17. The lower electrode 13 and the upper electrode 15 are each composed of a copper thin film or a copper alloy thin film and each form a predetermined electrode pattern having a specified thickness of 70 μm to 200 μm. The far end (or the opposite end in the longitudinal direction) of the P-type semiconductor and the N-type semiconductor is plated with nickel.

The lower electrode 13 composed of a copper film or a copper alloy film having the specified electrode pattern shown in Fig. 2A is bonded to the insulating layer 12 of the first heat exchanger 11. Subsequently, as shown in FIG. 1B, the thermoelectric elements 14 composed of a P-type semiconductor and an N-type semiconductor are alternately aligned on the lower electrode 13, wherein the lower ends of the thermoelectric elements 14 are via a solder alloy (for example, a SnSb alloy). The AuSn alloy and the SnAgCu alloy are attached to the lower electrode 13. Further, an upper electrode 15 composed of a copper film or a copper alloy film having the specified electrode pattern shown in Fig. 2B is disposed on the upper ends of the thermoelectric elements 14.

Thereafter, the upper electrode 15 is attached to the upper ends of the thermoelectric elements 14 via a solder alloy (for example, a SnSb alloy, an AuSn alloy, and a SnAgCu alloy). Therefore, the thermoelectric elements 14 composed of a P-type semiconductor and an N-type semiconductor are alternately aligned and electrically connected in series between the lower electrode 13 and the upper electrode 15.

Finally, as shown in FIG. 1C, the insulating layer 17 of the second heat exchanger 16 is brought into contact with the upper electrode 15; then, the upper electrode 15 is attached to the insulating layer 17. This completes the manufacture of the heat exchange unit 10 of the first embodiment.

(b) Use of heat exchange unit 10

The heat exchange unit 10 of the first embodiment can be used to control the temperature of a gaseous substance. That is, the heat exchange unit 10 is configured such that the heat sink fins 16a of the second heat exchanger 16 (which acts as an endothermic air-cooling fin) enter the gaseous material subjected to temperature control. In this state, electricity is applied to the thermoelectric module M, wherein the thermoelectric elements 14 are electrically connected in series between the "heat-dissipating" lower electrode 13 and the "endothermic" upper electrode 15, so that the upper electrode 15 is cooled. The heat is absorbed from the gaseous substance subjected to temperature control by the heat radiating fins 16a of the second heat exchanger 16. In this regard, heat is generated in the lower electrode 13 being heated, but is dissipated via the heat radiating fins 11a of the first heat exchanger 11.

(c) Measurement of the maximum endothermic value Qmax

Using the heat exchange unit 10 of the first embodiment, it is possible to measure the maximum heat-absorption or endothermic value Qmax constituting a performance evaluation reference by the following procedure. Test examples A1 to A3, B1 to B4, and C1 to C3 were fabricated based on the heat exchange unit 10. As shown in Fig. 3, the heat exchange unit 10 (i.e., test examples A1-A3, B1-B4, and C1-C3 of the heat exchange unit) was placed at the opening of the box using the heat insulating box X.

The heat dissipating fins 16a of the second heat exchanger 16 (serving as a heat sink) are disposed in the heat insulating box X, and the heat dissipating fins 11a of the first heat exchanger 11 (serving as a heat sink) are disposed outside the heat insulating box X. The heat exchange unit 10 is disposed in the heat insulating box X, in which heat is transferred from the inside of the heat insulating box X to the outside. A heater H serving as a virtual heat source for generating a specified heating value is disposed in the heat insulating box X.

The heat exchange unit 10 is driven to measure a maximum heat generation value (W) at which the internal temperature of the heat insulating box X coincides with the external temperature as the maximum heat absorption value Qmax. The measurement results show that the heat exchange unit A1 indicates Qmax = 113 W, the heat exchange unit A2 indicates Qmax = 114 W, and the heat exchange unit A3 indicates Qmax = 113 W. In addition, the heat exchange unit B1 indicates Qmax=116W, the heat exchange unit B2 indicates Qmax=115W, the heat exchange unit B3 indicates Qmax=114W, and the heat exchange unit B4 indicates Qmax=115W. Further, the heat exchange unit C1 indicates Qmax=110W, the heat exchange unit C2 indicates Qmax=111W, and the heat exchange unit C3 indicates Qmax=110W.

In the above, the heat exchange unit A1 was fabricated such that a filler composed of alumina (Al ₂ O ₃ ) powder was dispersed in the polyimide film to form insulating layers 12 and 17 having a thickness of 15 μm. The heat exchange unit A2 was fabricated such that a filler composed of alumina (Al ₂ O ₃ ) powder was dispersed in the lacquered polyimide resin to form insulating layers 12 and 17 having a thickness of 15 μm. The heat exchange unit A3 was fabricated such that a filler composed of alumina (Al ₂ O ₃ ) powder was dispersed in the epoxy resin sheet to form insulating layers 12 and 17 having a thickness of 20 μm.

Further, the heat exchange unit B1 was fabricated such that a filler composed of aluminum nitride (AlN) powder was dispersed in the epoxy resin sheet, thereby forming insulating layers 12 and 17 having a thickness of 20 μm. The heat exchange unit B2 was fabricated such that a filler composed of alumina (Al ₂ O ₃ ) powder was dispersed in the paint epoxy resin to form insulating layers 12 and 17 having a thickness of 20 μm. The heat exchange unit B3 was fabricated such that a filler composed of magnesium oxide (MgO) powder was dispersed in the paint epoxy resin to form insulating layers 12 and 17 having a thickness of 20 μm. The heat exchange unit B4 was fabricated such that a filler composed of cerium carbide (SiC) powder was dispersed in the lacquer epoxy resin to form insulating layers 12 and 17 having a thickness of 20 μm.

Further, the heat exchange unit C1 was fabricated such that a filler composed of alumina (Al ₂ O ₃ ) powder was dispersed in a polyimide film of a 10 μm thick alumite layer to form an insulation having a thickness of 100 μm. Layers 12 and 17. The heat exchange unit C2 was fabricated such that a filler composed of alumina (Al ₂ O ₃ ) powder was dispersed in an epoxy resin sheet on a 10 μm thick alumite layer, thereby forming insulating layers 12 and 17 having a thickness of 50 μm. . Manufacturing a heat exchange unit C3 such that a filler composed of alumina (Al ₂ O ₃ ) powder is dispersed in a painted epoxy resin on a 10 μm thick alumite layer to form an insulating layer 12 having a thickness of 50 μm and 17.

(d) Measurement of withstand voltage WS

The heat exchange is performed based on the heat exchange units A1, A2, and A3 by changing the surface roughness Ra on the surface of the first heat exchanger 11 adjacent to the insulating layer 12 and on the surface of the second heat exchanger 16 adjacent to the insulating layer 17. Units A11 to A19, A21 to A29, and A31 to A39. The withstand voltage WS is measured with respect to the heat exchange units A11-A19, A21-A29, and A31-A39 using different values of the surface roughness Ra.

Specifically, the surface roughness Ra (adjacent to the surface of the first heat exchanger 11 adjacent to the insulating layer 12 and the surface of the second heat exchanger 16 adjacent to the insulating layer 17) is changed with respect to the heat exchange unit A1, so that heat The exchange unit A11 has a surface roughness of 0.3 μm, the heat exchange unit A12 has a surface roughness of 0.5 μm, the heat exchange unit A13 has a surface roughness of 1.0 μm, the heat exchange unit A14 has a surface roughness of 1.6 μm, and the heat exchange unit A15 has a surface roughness of 2.2 μm, heat exchange unit A16 has a surface roughness of 3.2 μm, heat exchange unit A17 has a surface roughness of 4.4 μm, heat exchange unit A18 has a surface roughness of 4.7 μm, and heat exchange unit A19 It has a surface roughness of 5.1 μm. Further, a heat exchange unit A1a having a surface roughness of 0.07 μm and a heat exchange unit A1b having a surface roughness of 0.1 μm were produced based on the heat exchange unit A1, and the withstand voltage WS was measured. The measurement results are shown in Table 1-1, in which the insulating layer 12 (17) is a 15 μm thick polyimide film, and the filler is composed of alumina (Al ₂ O ₃ ).

Further, the surface roughness Ra is changed with respect to the heat exchange unit A2 so that the heat exchange unit A21 has a surface roughness of 0.3 μm, the heat exchange unit A22 has a surface roughness of 0.5 μm, and the heat exchange unit A23 has a surface roughness of 1.0 μm. The heat exchange unit A24 has a surface roughness of 1.3 μm, the heat exchange unit A25 has a surface roughness of 2.4 μm, the heat exchange unit A26 has a surface roughness of 3.2 μm, and the heat exchange unit A27 has a surface roughness of 4.3 μm, heat. The exchange unit A28 has a surface roughness of 4.7 μm, and the heat exchange unit A29 has a surface roughness of 5.1 μm. Further, a heat exchange unit A2a having a surface roughness of 0.07 μm and a heat exchange unit A2b having a surface roughness of 0.1 μm were produced based on the heat exchange unit A2, and the withstand voltage WS was measured. The measurement results are shown in Table 1-2, in which the insulating layer 12 (17) is a 15 μm thick polyimine varnish, and the filler is composed of alumina (Al ₂ O ₃ ).

Further, the surface roughness Ra is changed with respect to the heat exchange unit A3 such that the heat exchange unit A31 has a surface roughness of 0.3 μm, the heat exchange unit A32 has a surface roughness of 0.5 μm, and the heat exchange unit A33 has a surface roughness of 1.0 μm. The heat exchange unit A34 has a surface roughness of 1.6 μm, the heat exchange unit A35 has a surface roughness of 2.2 μm, the heat exchange unit A36 has a surface roughness of 3.2 μm, and the heat exchange unit A37 has a surface roughness of 4.4 μm, heat. The exchange unit A38 has a surface roughness of 4.7 μm, and the heat exchange unit A39 has a surface roughness of 5.0 μm. Further, a heat exchange unit A3a having a surface roughness of 0.07 μm and a heat exchange unit A3b having a surface roughness of 0.1 μm were produced based on the heat exchange unit A3, and the withstand voltage WS was measured. The measurement results are shown in Tables 1-3, in which the insulating layer 12 (17) is a 20 μm thick epoxy sheet, and the filler is composed of alumina (Al ₂ O ₃ ).

As shown in FIG. 4, the measurement of the withstand voltage WS is performed using the heat exchanger 11 (16) adjacent to the insulating layer 12 (17), and the electrode 13 (15) is formed in the insulating layer 12 (17) in a prescribed pattern. Above, a plurality of probes P are placed at specified positions of the electrodes 13 (15) and then brought into contact with the electrodes 13 (15). A specified voltage V was applied to the probes P for five seconds to measure the withstand voltage WS when the leakage current exceeded 5 mA.

The measurement results of the heat exchange units A11-A19, A21-A29, and A31-A39 in Table 1-1, Table 1-2, and Table 1-3 are plotted on the graph of FIG. 5, and the pattern of FIG. 5 is plotted. The horizontal axis represents the surface roughness Ra (μm) and the vertical axis of the graph of Fig. 5 represents the withstand voltage WS (kV), thereby plotting the measurement curves (or broken lines) A1, A2, and A3. The above measurement results shown in FIG. 5 and Table 1-1 to Table 1-3 clearly show that the withstand voltage WS is good when the surface roughness Ra is less than 4.7 μm, but when the surface roughness Ra exceeds 4.7 μm. Decrease rapidly. Therefore, the surface roughness Ra of the heat exchanger 11 (16) is preferably less than 4.7 μm.

Next, the surface roughness on the surface of the first heat exchanger 11 adjacent to the insulating layer 12 and on the surface of the second heat exchanger 16 adjacent to the insulating layer 17 is changed based on the heat exchange units B1, B2, B3, and B4. Ra manufactures heat exchange units B11 to B19, B21 to B29, B31 to B39, and B41 to B49. The withstand voltage WS is measured with respect to the heat exchange units B11-B19, B21-B29, B31-B39, and B41-B49 using different values of the surface roughness Ra.

Specifically, the surface roughness Ra of the surface of the first heat exchanger 11 adjacent to the insulating layer 12 and adjacent to the surface of the second heat exchanger 16 of the insulating layer 17 is changed with respect to the heat exchange unit B1, so that heat The exchange unit B11 has a surface roughness of 0.3 μm, the heat exchange unit B12 has a surface roughness of 0.5 μm, the heat exchange unit B13 has a surface roughness of 1.0 μm, and the heat exchange unit B14 has a surface roughness of 1.6 μm, and the heat exchange unit B15 has a surface roughness of 2.2 μm, heat exchange unit B16 has a surface roughness of 3.2 μm, heat exchange unit B17 has a surface roughness of 4.4 μm, heat exchange unit B18 has a surface roughness of 4.7 μm, and heat exchange unit B19 It has a surface roughness of 5.2 μm. Further, a heat exchange unit B1a having a surface roughness of 0.07 μm and a heat exchange unit B1b having a surface roughness of 0.1 μm were produced based on the heat exchange unit B1, and the withstand voltage WS was measured. The measurement results are shown in Table 2-1, in which the insulating layer 12 (17) is a 20 μm thick epoxy sheet, and the filler is composed of aluminum nitride (AlN).

Further, the surface roughness Ra is changed with respect to the heat exchange unit B2 such that the heat exchange unit B21 has a surface roughness of 0.3 μm, the heat exchange unit B22 has a surface roughness of 0.5 μm, and the heat exchange unit B23 has a surface roughness of 1.0 μm. The heat exchange unit B24 has a surface roughness of 1.6 μm, the heat exchange unit B25 has a surface roughness of 2.1 μm, the heat exchange unit B26 has a surface roughness of 3.3 μm, and the heat exchange unit B27 has a surface roughness of 4.4 μm, heat. The exchange unit B28 has a surface roughness of 4.7 μm, and the heat exchange unit B29 has a surface roughness of 5.1 μm. Further, a heat exchange unit B2a having a surface roughness of 0.07 μm and a heat exchange unit B2b having a surface roughness of 0.1 μm were produced based on the heat exchange unit B2, and the withstand voltage WS was measured. The measurement results are shown in Table 2-2, in which the insulating layer 12 (17) is a 20 μm thick epoxy varnish, and the filler is composed of alumina (Al ₂ O ₃ ).

Further, the surface roughness Ra is changed with respect to the heat exchange unit B3 such that the heat exchange unit B31 has a surface roughness of 0.3 μm, the heat exchange unit B32 has a surface roughness of 0.5 μm, and the heat exchange unit B33 has a surface roughness of 1.0 μm. The heat exchange unit B34 has a surface roughness of 1.6 μm, the heat exchange unit B35 has a surface roughness of 2.2 μm, the heat exchange unit B36 has a surface roughness of 3.3 μm, and the heat exchange unit B37 has a surface roughness of 4.5 μm, heat. The exchange unit B38 has a surface roughness of 4.7 μm, and the heat exchange unit B39 has a surface roughness of 5.1 μm. Further, a heat exchange unit B3a having a surface roughness of 0.07 μm and a heat exchange unit B3b having a surface roughness of 0.1 μm were produced based on the heat exchange unit B3, and the withstand voltage WS was measured. The measurement results are shown in Table 2-3, in which the insulating layer 12 (17) is a 20 μm thick epoxy varnish, and the filler is composed of magnesium oxide (MgO).

Further, the surface roughness Ra is changed with respect to the heat exchange unit B4 such that the heat exchange unit B41 has a surface roughness of 0.3 μm, the heat exchange unit B42 has a surface roughness of 0.5 μm, and the heat exchange unit B43 has a surface roughness of 1.0 μm. The heat exchange unit B44 has a surface roughness of 1.6 μm, the heat exchange unit B45 has a surface roughness of 2.2 μm, the heat exchange unit B46 has a surface roughness of 3.4 μm, and the heat exchange unit B47 has a surface roughness of 4.5 μm, heat. The exchange unit B48 has a surface roughness of 4.7 μm, and the heat exchange unit B49 has a surface roughness of 5.1 μm. Further, a heat exchange unit B4a having a surface roughness of 0.07 μm and a heat exchange unit B4b having a surface roughness of 0.1 μm were produced based on the heat exchange unit B4, and the withstand voltage WS was measured. The measurement results are shown in Tables 2-4, in which the insulating layer 12 (17) is a 20 μm thick epoxy varnish, and the filler is composed of tantalum carbide (SiC).

The heat exchange units B11-B19, B21-B29, B31-B39 and B41-B49 in Table 2-1, Table 2-2, Table 2-3 and Table 2-4 are plotted on the graph of Fig. 5. Measure the results to plot the measured curves (or broken lines) B1, B2, B3, and B4. The above measurement results shown in FIG. 5 and Table 2-1 to Table 2-4 clearly show that the withstand voltage WS is good when the surface roughness Ra is less than 4.7 μm, but when the surface roughness Ra exceeds 4.7 μm. Decrease rapidly. Therefore, the surface roughness Ra of the heat exchanger 11 (16) is preferably less than 4.7 μm.

Next, based on the heat exchange units C1, C2, and C3, the surface roughness Ra on the surface of the first heat exchanger 11 adjacent to the insulating layer 12 and the surface of the second heat exchanger 16 adjacent to the insulating layer 17 is changed. The heat exchange units C11 to C19, C21 to C29, and C31 to C39 are manufactured. The withstand voltage WS is measured with respect to the heat exchange units C11-C19, C21-C29, and C31-C39 using different values of the surface roughness Ra.

Specifically, the surface roughness Ra of the surface of the first heat exchanger 11 adjacent to the insulating layer 12 and adjacent to the surface of the second heat exchanger 16 of the insulating layer 17 is changed with respect to the heat exchange unit C1, so that heat The exchange unit C11 has a surface roughness of 0.3 μm, the heat exchange unit C12 has a surface roughness of 0.5 μm, the heat exchange unit C13 has a surface roughness of 1.0 μm, the heat exchange unit C14 has a surface roughness of 1.5 μm, and the heat exchange unit C15 has a surface roughness of 2.2 μm, heat exchange unit C16 has a surface roughness of 3.2 μm, heat exchange unit C17 has a surface roughness of 4.4 μm, heat exchange unit C18 has a surface roughness of 4.7 μm, and heat exchange unit C19 It has a surface roughness of 5.1 μm. Further, a heat exchange unit C1a having a surface roughness of 0.06 μm and a heat exchange unit C1b having a surface roughness of 0.1 μm were produced based on the heat exchange unit C1, and the withstand voltage WS was measured. The measurement results are shown in Table 3-1, in which the insulating layer 12 (17) is a 100 μm thick polyimide film plus a 10 μm thick alumite layer, and the filler is made of alumina (Al ₂ O ₃ ). composition.

Further, the surface roughness Ra is changed with respect to the heat exchange unit C2 such that the heat exchange unit C21 has a surface roughness of 0.3 μm, the heat exchange unit C22 has a surface roughness of 0.5 μm, and the heat exchange unit C23 has a surface roughness of 1.0 μm. The heat exchange unit C24 has a surface roughness of 1.5 μm, the heat exchange unit C25 has a surface roughness of 2.2 μm, the heat exchange unit C26 has a surface roughness of 3.2 μm, and the heat exchange unit C27 has a surface roughness of 4.4 μm, which is hot. The exchange unit C28 has a surface roughness of 4.7 μm, and the heat exchange unit C29 has a surface roughness of 5.1 μm. Further, a heat exchange unit C2a having a surface roughness of 0.06 μm and a heat exchange unit C2b having a surface roughness of 0.1 μm were produced based on the heat exchange unit C2, and the withstand voltage WS was measured. The measurement results are shown in Table 3-2, in which the insulating layer 12 (17) is a 50 μm thick epoxy sheet plus a 10 μm thick alumite layer, and the filler consists of alumina (Al ₂ O ₃ ).

Further, the surface roughness Ra is changed with respect to the heat exchange unit C3 so that the heat exchange unit C31 has a surface roughness of 0.3 μm, the heat exchange unit C32 has a surface roughness of 0.5 μm, and the heat exchange unit C33 has a surface roughness of 1.0 μm. The heat exchange unit C34 has a surface roughness of 1.6 μm, the heat exchange unit C35 has a surface roughness of 2.2 μm, the heat exchange unit C36 has a surface roughness of 3.2 μm, and the heat exchange unit C37 has a surface roughness of 4.4 μm, and the heat is The exchange unit C38 has a surface roughness of 4.7 μm, and the heat exchange unit C39 has a surface roughness of 5.1 μm. Further, a heat exchange unit C3a having a surface roughness of 0.06 μm and a heat exchange unit C3b having a surface roughness of 0.1 μm were produced based on the heat exchange unit C3, and the withstand voltage WS was measured. The measurement results are shown in Table 3-3, in which the insulating layer 12 (17) is a 50 μm thick epoxy varnish plus a 10 μm thick alumite layer, and the filler consists of alumina (Al ₂ O ₃ ).

The measurement results of the heat exchange units C11-C19, C21-C29 and C31-C39 in Table 3-1, Table 3-2 and Table 3-3 are plotted on the graph of Fig. 5, thereby plotting the measurement curve (or disconnected) C1, C2 and C3. The above measurement results shown in FIG. 5 and Table 3-1 to Table 3-3 clearly show that the withstand voltage WS is good when the surface roughness Ra is less than 4.7 μm, but when the surface roughness Ra exceeds 4.7 μm. Decrease rapidly. Therefore, the surface roughness Ra of the heat exchanger 11 (16) is preferably less than 4.7 μm.

2. Second Embodiment

The first embodiment is directed to the heat exchange unit 10 constituted by the first heat exchanger 11 and the second heat exchanger 16 each serving as an air cooling fin, which is not a limitation; therefore, it is possible to use a water-cooling fin. The second embodiment was designed to use a water-cooled fin as the first heat exchanger and the second heat exchanger.

The heat exchange unit 20 according to the second embodiment of the present invention will be described with reference to Figs. 6A to 6C. As shown in FIG. 6C, the heat exchange unit 20 is composed of a first heat exchanger (serving as a heat-dissipating or heat-absorbing water-cooling fin) 21, and an insulation formed on the surface of the first heat exchanger 21. a layer 22, a lower electrode disposed on the insulating layer 22 (serving as a heat dissipating or heat absorbing electrode) 23, a plurality of thermoelectric elements 24 bonded to the lower electrode 23, and a plurality of upper electrodes bonded to the thermoelectric elements 24 A heat dissipating or heat absorbing electrode 25, a second heat exchanger (serving as a heat dissipating heat sinking heat sink) 26, and an insulating layer 27 formed on the surface of the second heat exchanger 26. A pair of terminals (none of which are shown) connected to a pair of leads are formed on one end of the lower electrode 23.

A thermoelectric module M (see FIG. 8) is composed of the thermoelectric elements 24, and the thermoelectric elements are electrically connected in series between the lower electrode 23 and the upper electrode 25 via a bonding metal such as solder.

The first heat exchanger 21 and the second heat exchanger 26 are each composed of aluminum or an aluminum alloy having a high thermal conductivity, wherein (the surface adjacent to the insulating layer 22) the surface of the first heat exchanger 21 and (adjacent to the insulating layer 27) The surfaces of the second heat exchanger 26 are each trimmed to have a surface roughness Ra of 5 μm or less. In addition, a plurality of channels 21a (allowing a cooling medium, that is, water, flowing in a specified direction, that is, from right to left) are formed in the first heat exchanger 21, and a plurality of channels 26a are formed in the second In the heat exchanger 26. As shown in FIG. 7A, a plurality of mounting holes 21b are formed on the surface of the first heat exchanger 21 such that the lower electrode 23 and the upper electrode 25 are not aligned on the surface. As shown in Fig. 7B, a plurality of mounting holes 26b are formed on the surface of the second heat exchanger 26 such that the lower electrode 23 and the upper electrode 25 are not aligned on the surface.

Each of the insulating layers 22 and 27 is composed of a polyimide resin, an epoxy resin or an alumite, and the insulating layers have a thickness of 10 μm to 100 μm. Preferably, a filler composed of alumina (Al ₂ O ₃ ), aluminum nitride (AlN), magnesium oxide (MgO) or tantalum carbide (SiC) having an average particle diameter of 15 μm or less is dispersed to the polyruthenium. The insulating layer 22 and 27 are composed of an amine resin or an epoxy resin to improve the thermal conductivity. Further, it is preferred to laminate a polyimine resin or an epoxy resin in which a filler is dispersed on the insulating layers 22 and 27 composed of alumite.

When the lower electrode 23 functions as a heat radiating electrode, the upper electrode 25 functions as a heat absorbing electrode, or when the lower electrode 23 functions as a heat absorbing electrode, the upper electrode 25 functions as a heat radiating electrode. The lower electrode 23 and the upper electrode 25 are each composed of a copper film or a copper alloy film having a thickness of 70 μm to 200 μm. The lower electrode 23 has an alignment pattern as shown in FIG. 7A, and the upper electrode 25 has an alignment pattern as shown in FIG. 7B. Each section of the lower electrode 23 is formed into a rectangular shape having a length of 3 mm and a short length of 1.8 mm. Similarly, each section of the upper electrode 25 is formed into a rectangular shape having a length of 3 mm and a short length of 1.8 mm.

The thermoelectric elements 24 composed of a P-type semiconductor and an N-type semiconductor are electrically connected in series between the lower electrode 23 and the upper electrode 25 in such a manner that the P-type semiconductor and the N-type semiconductor are alternately aligned. The thermoelectric elements 24 are soldered to the lower electrode 23 and the upper electrode 25 via a SnSb alloy, an AuSn alloy, or a SnAgCu alloy. The distal ends of the thermoelectric elements 24 are nickel plated so that the thermoelectric elements 24 can be easily soldered to the lower electrode 23 and the upper electrode 25.

The thermoelectric elements 24 are preferably composed of a sintered thermoelectric material of Bi-Te having high thermoelectric efficiency at room temperature. Specifically, a P-type semiconductor composed of a ternary compound of Bi-Sb-Te and an N-type semiconductor composed of a quaternary compound of Bi-Sb-Te-Se are preferably used. In the current embodiment, the P-type semiconductor is composed of Bi _0.5 Sb _1.5 Te ₃ and the N-type semiconductor is composed of Bi _1.9 Sb _0.1 Te _2.6 Se _0.4 , wherein the semiconductors are liquid-quenched to produce foil powder, and the foil powder is then The heat is pressed to form a block which is then cut into small pieces each having a specified size of 1.35 mm long, 1.35 mm wide, and 1.5 mm high.

(a) Manufacturing of heat exchange unit 20

The heat exchange unit 20 is manufactured by the following procedure.

First, a first heat exchanger 21 (serving as a heat-dissipating water-cooling fin) is prepared such that an adhesive insulating layer 22 is formed on the surface of the heat exchanger, and a plurality of channels 21a are formed in the heat exchanger. To allow a cooling medium (ie, water) to flow through the channels. Similarly, a second heat exchanger 26 (serving as an endothermic water-cooling fin) is prepared such that an adhesive insulating layer 27 is formed on the surface of the heat exchanger, and a plurality of channels 26a are formed in the heat exchanger Internally, a cooling medium (i.e., water) is allowed to flow through the channels. Further, the lower electrode 23 (serving as a heat radiating electrode) and the upper electrode 25 (serving as a heat absorbing electrode) are prepared in advance. Further, the thermoelectric elements 24 composed of a P-type semiconductor and an N-type semiconductor are prepared in advance.

The first heat exchanger 21 and the second heat exchanger 26 are each composed of aluminum or an aluminum alloy having a high thermal conductivity. The surface of the first heat exchanger 21 (which is adjacent to the insulating layer 22) and the surface of the second heat exchanger 26 (which is adjacent to the insulating layer 27) are each trimmed to have a surface roughness Ra of 5 μm or less. The insulating layers 22 and 27 are formed by dispersing a filler composed of Al ₂ O ₃ , AlN, MgO or SiC into an adhesive polyimide or epoxy layer. Alternatively, the insulating layers are formed using a composite layer in which a polyimine resin layer or an epoxy layer in which a filler is dispersed is formed on the alumite layer. Here, the insulating layers 22 and 27 are formed by crimping the material of the sheet shape. Alternatively, the varnish is applied to a sheet-shaped material, which is then cured to form insulating layers 22 and 27. The lower electrode 23 and the upper electrode 25 are each composed of a copper thin film or a copper alloy thin film and each form a predetermined electrode pattern having a specified thickness of 70 μm to 200 μm. The far end (or the opposite end in the longitudinal direction) of the P-type semiconductor and the N-type semiconductor is plated with nickel.

As shown in FIG. 6A, the lower electrode 23 composed of a copper film or a copper alloy film having the specified electrode pattern shown in FIG. 7A is bonded to the insulating layer 22 of the first heat exchanger 21. Subsequently, as shown in FIG. 6B, the thermoelectric elements 24 composed of a P-type semiconductor and an N-type semiconductor are alternately aligned on the lower electrode 23, wherein the lower ends of the thermoelectric elements 24 are via a solder alloy (for example, a SnSb alloy) The AuSn alloy and the SnAgCu alloy are attached to the lower electrode 23. Further, an upper electrode 25 composed of a copper film or a copper alloy film having the specified electrode pattern shown in Fig. 7B is disposed on the upper ends of the thermoelectric elements 24.

Thereafter, the upper electrode 25 is attached to the upper ends of the thermoelectric elements 24 via a solder alloy (for example, a SnSb alloy, an AuSn alloy, and a SnAgCu alloy). Therefore, the thermoelectric elements 24 composed of a P-type semiconductor and an N-type semiconductor are alternately aligned and electrically connected in series between the lower electrode 23 and the upper electrode 25.

Finally, as shown in FIG. 6C, the insulating layer 27 of the second heat exchanger 26 is brought into contact with the upper electrode 25; then, the upper electrode 25 is attached to the insulating layer 27. This completes the manufacture of the heat exchange unit 20 of the second embodiment.

(b) Use of heat exchange unit 20

The heat exchange unit 20 of the second embodiment can be used to control the temperature of a specified object (i.e., a body that requires temperature control, not shown). For example, hot water warmed by absorbing heat from the designated object is supplied to the inlet of the passage 26a of the "endothermic" second heat exchanger 26, and the outlet of the passage 26a is connected to the designated object. Further, cold water is supplied to the inlet of the passage 21a of the first heat exchanger 21, and the outlet of the passage 21a is used as a drain. In this state, electricity is applied to the thermoelectric module M, wherein the thermoelectric elements 24 are electrically connected in series between the "heat-dissipating" lower electrode 23 and the "endothermic" upper electrode 25, and are cooled by the upper electrode 25. The heat is absorbed from the hot water supplied to the designated object via the "endothermic" second heat exchanger 26, and the "heat-dissipating" lower electrode 23 is heated so that its heat flows through the "heat-dissipating" first heat exchanger The cold water of channel 21a of 21 is dissipated.

(c) Measurement of the maximum endothermic value Qmax

Using the heat exchange unit 20 of the second embodiment, it is possible to measure the maximum heat-absorption or endothermic value Qmax constituting a performance evaluation reference by the following procedure. Test examples D1 to D3 and E1 to E2 were fabricated based on the heat exchange unit 20. As shown in Fig. 8, the heat exchange unit 20 (i.e., test examples D1-D3, E1, and E2 of the heat exchange unit) was placed therein using a vacuum chamber Y. Next, a hot water pipe (not shown) is connected to the inlet of the passage 26a of the second heat exchanger 26, and a drain pipe (not shown) is connected to the outlet of the passage 26a.

Further, a cold water pipe (not shown) is connected to the inlet of the passage 21a of the first heat exchanger 21, and a drain pipe (not shown) is connected to the outlet of the passage 21a.

The heat exchange unit 20 is driven to measure the inlet temperature and the outlet temperature of the passage 21a and the inlet temperature and the outlet temperature of the passage 26a for ten minutes, wherein the measurement is performed by increasing the inlet temperature to measure the average value of the outlet temperature, thereby estimating Maximum endothermic value Qmax. The measurement results show that the heat exchange unit D1 indicates Qmax=218W, the heat exchange unit D2 indicates Qmax=222W, and the heat exchange unit D3 indicates Qmax=220W. In addition, the heat exchange unit E1 indicates Qmax = 225W, and the heat exchange unit E2 indicates Qmax = 224W.

In the above, the heat exchange unit D1 was fabricated such that a filler composed of alumina (Al ₂ O ₃ ) powder was dispersed in a polyimide film of a 5 μm thick alumite layer to form a thickness of 30 μm. Insulation layers 22 and 27. The heat exchange unit D2 was fabricated such that a filler composed of alumina (Al ₂ O ₃ ) powder was dispersed in an epoxy resin sheet on a 5 μm thick alumite layer, thereby forming insulating layers 22 and 27 having a thickness of 20 μm. . Manufacturing a heat exchange unit D3 such that a filler composed of alumina (Al ₂ O ₃ ) powder is dispersed in a painted epoxy resin on a 5 μm thick alumite layer to form an insulating layer 22 having a thickness of 20 μm and 27.

Further, the heat exchange unit E1 was fabricated such that a filler composed of magnesium oxide (MgO) powder was dispersed in the epoxy resin sheet to form insulating layers 22 and 27 having a thickness of 20 μm. The heat exchange unit E2 was fabricated such that a filler composed of cerium carbide (SiC) powder was dispersed in the epoxy resin sheet to form insulating layers 22 and 27 having a thickness of 20 μm.

(d) Measurement of withstand voltage WS

The heat exchange is performed based on the heat exchange units D1, D2, and D3 by changing the surface roughness Ra on the surface of the first heat exchanger 21 adjacent to the insulating layer 22 and on the surface of the second heat exchanger 26 adjacent to the insulating layer 27. Units D11 to D19, D21 to D29, and D31 to D39. The withstand voltage WS is measured with respect to the heat exchange units D11-D19, D21-D29, and D31-D39 using different values of the surface roughness Ra.

Specifically, the surface roughness Ra (adjacent to the surface of the first heat exchanger 21 adjacent to the insulating layer 22 and the surface of the second heat exchanger 26 adjacent to the insulating layer 27) is changed with respect to the heat exchange unit D1, so that heat The exchange unit D11 has a surface roughness of 0.3 μm, the heat exchange unit D12 has a surface roughness of 0.5 μm, the heat exchange unit D13 has a surface roughness of 1.0 μm, the heat exchange unit D14 has a surface roughness of 1.6 μm, and the heat exchange unit D15 has a surface roughness of 2.1 μm, heat exchange unit D16 has a surface roughness of 3.2 μm, heat exchange unit D17 has a surface roughness of 4.4 μm, heat exchange unit D18 has a surface roughness of 4.7 μm, and heat exchange unit D19 It has a surface roughness of 5.1 μm. Further, a heat exchange unit D1a having a surface roughness of 0.06 μm and a heat exchange unit D1b having a surface roughness of 0.1 μm were produced based on the heat exchange unit D1, and the withstand voltage WS was measured. The measurement results are shown in Table 4-1, in which the insulating layer 22 (27) is a 30 μm thick polyimide film plus a 5 μm thick alumite layer, and the filler is made of alumina (Al ₂ O ₃ ). composition.

Further, the surface roughness Ra is changed with respect to the heat exchange unit D2 such that the heat exchange unit D21 has a surface roughness of 0.3 μm, the heat exchange unit D22 has a surface roughness of 0.5 μm, and the heat exchange unit D23 has a surface roughness of 1.0 μm. The heat exchange unit D24 has a surface roughness of 1.6 μm, the heat exchange unit D25 has a surface roughness of 2.1 μm, the heat exchange unit D26 has a surface roughness of 3.2 μm, and the heat exchange unit D27 has a surface roughness of 4.4 μm, heat. The exchange unit D28 has a surface roughness of 4.7 μm, and the heat exchange unit D29 has a surface roughness of 5.1 μm. Further, a heat exchange unit D2a having a surface roughness of 0.06 μm and a heat exchange unit D2b having a surface roughness of 0.1 μm were produced based on the heat exchange unit D2, and the withstand voltage WS was measured. The measurement results are shown in Table 4-2, in which the insulating layer 22 (27) is a 20 μm thick epoxy sheet plus a 5 μm thick alumite layer, and the filler consists of alumina (Al ₂ O ₃ ).

Further, the surface roughness Ra is changed with respect to the heat exchange unit D3 such that the heat exchange unit D31 has a surface roughness of 0.3 μm, the heat exchange unit D32 has a surface roughness of 0.5 μm, and the heat exchange unit D33 has a surface roughness of 1.0 μm. The heat exchange unit D34 has a surface roughness of 1.6 μm, the heat exchange unit D35 has a surface roughness of 2.1 μm, the heat exchange unit D36 has a surface roughness of 3.2 μm, and the heat exchange unit D37 has a surface roughness of 4.4 μm, heat. The exchange unit D38 has a surface roughness of 4.7 μm, and the heat exchange unit D39 has a surface roughness of 5.1 μm. Further, a heat exchange unit D3a having a surface roughness of 0.06 μm and a heat exchange unit D3b having a surface roughness of 0.1 μm were produced based on the heat exchange unit D3, and the withstand voltage WS was measured. The measurement results are shown in Table 4-3, in which the insulating layer 22 (27) is a 20 μm thick epoxy varnish plus a 5 μm thick alumite layer, and the filler consists of alumina (Al ₂ O ₃ ).

The measurement results of the heat exchange units D11-D19, D21-D29 and D31-D39 in Table 4-1, Table 4-2 and Table 4-3 are plotted on the graph of Fig. 9, and the pattern of Fig. 9 is plotted. The horizontal axis represents the surface roughness Ra (μm) and the vertical axis of the graph of Fig. 9 represents the withstand voltage WS(kV), thereby plotting the measurement curves (or broken lines) D1, D2, and D3. The above measurement results shown in FIG. 9 and Table 4-1 to Table 4-3 clearly show that the withstand voltage WS is good when the surface roughness Ra is less than 4.7 μm, but when the surface roughness Ra exceeds 4.7 μm. Decrease rapidly. Therefore, the surface roughness Ra of the heat exchanger 21 (26) is preferably less than 4.7 μm.

Similarly, the surface roughness Ra is changed with respect to the heat exchange unit E1 such that the heat exchange unit E11 has a surface roughness of 0.3 μm, the heat exchange unit E12 has a surface roughness of 0.5 μm, and the heat exchange unit E13 has a surface roughness of 1.0 μm. Degree, the heat exchange unit E14 has a surface roughness of 1.6 μm, the heat exchange unit E15 has a surface roughness of 2.1 μm, the heat exchange unit E16 has a surface roughness of 3.2 μm, and the heat exchange unit E17 has a surface roughness of 4.4 μm. The heat exchange unit E18 has a surface roughness of 4.7 μm, and the heat exchange unit E19 has a surface roughness of 5.1 μm. Further, a heat exchange unit E1a having a surface roughness of 0.07 μm and a heat exchange unit E1b having a surface roughness of 0.1 μm were produced based on the heat exchange unit E1, and the withstand voltage WS was measured. The measurement results are shown in Table 5-1, in which the insulating layer 22 (27) is a 20 μm thick epoxy sheet, and the filler is composed of magnesium oxide (MgO).

Further, the surface roughness Ra is changed with respect to the heat exchange unit E2 so that the heat exchange unit E21 has a surface roughness of 0.3 μm, the heat exchange unit E22 has a surface roughness of 0.5 μm, and the heat exchange unit E23 has a surface roughness of 1.0 μm. The heat exchange unit E24 has a surface roughness of 1.6 μm, the heat exchange unit E25 has a surface roughness of 2.1 μm, the heat exchange unit E26 has a surface roughness of 3.2 μm, and the heat exchange unit E27 has a surface roughness of 4.4 μm, and the heat is The exchange unit E28 has a surface roughness of 4.7 μm, and the heat exchange unit E29 has a surface roughness of 5.1 μm. Further, a heat exchange unit E2a having a surface roughness of 0.07 μm and a heat exchange unit E2b having a surface roughness of 0.1 μm were produced based on the heat exchange unit E2, and the withstand voltage WS was measured. The measurement results are shown in Table 5-2, in which the insulating layer 22 (27) is a 20 μm thick epoxy sheet, and the filler is composed of tantalum carbide (SiC).

The measurement results of the heat exchange units E11-E19 and E21-E29 in Table 5-1 and Table 5-2 are plotted on the graph of Fig. 9 to draw measurement curves (or broken lines) E1 and E2. The above measurement results shown in FIG. 9 and Table 5-1 and Table 5-2 clearly show that the withstand voltage WS is good when the surface roughness Ra is less than 4.7 μm, but when the surface roughness Ra exceeds 4.7 μm. Decrease rapidly. Therefore, the surface roughness Ra of the heat exchanger 21 (26) is preferably less than 4.7 μm.

3. Third Embodiment

The heat exchange unit 10 of the first embodiment and the heat exchange unit 20 of the second embodiment are designed such that the electrodes 13, 15, 23 and 25 are uniformly formed on the surfaces of the heat exchangers 11, 16, 21 and 26; When the designated areas on the surface of the heat exchangers do not allow for uniform alignment of the electrodes thereon, it is possible to align the electrodes so as to be outside of a designated area on the surface of the heat exchangers. A third embodiment of the present invention is designed based on this concept.

A heat exchange unit 30 according to a third embodiment of the present invention will be described with reference to Figs. 10A to 10C. As shown in FIG. 10C, the heat exchange unit 30 is composed of a first heat exchanger (serving as a heat-dissipating or heat-absorbing water-cooling fin) 31 formed on the surface and the back surface of the first heat exchanger 31. The insulating layer 32a and 32b, a first lower electrode (serving as a heat dissipating or heat absorbing electrode) 33a formed on the insulating layer 32a, and a first upper electrode (serving as a heat dissipating or heat absorbing electrode) 33b formed on the insulating layer 32b a plurality of first thermoelectric elements 34a adjacent to the first lower electrode 33a, a plurality of second thermoelectric elements 34b adjacent to the first upper electrode 33b, and a second upper electrode adjacent to the upper ends of the first thermoelectric elements 34a (serving a heat dissipating or heat absorbing electrode 35a, a second lower electrode (serving as a heat dissipating or heat absorbing electrode) 35b adjacent to the lower end of the second thermoelectric element 34b, and a second heat exchanger (serving as a heat sink or heat absorbing water cooling fin) 36, an insulating layer 37 formed on the surface of the second heat exchanger 36 above the second upper electrode 35a, a third heat exchanger (serving as a heat sink or heat sinking heat sink) 38, and a The second lower electrode 35b is formed under the third heat exchange An insulating layer 39 on the surface of the device 38. A pair of terminals (none of which are shown) connected to the pair of leads are formed on one end of the first lower electrode 33a.

As shown in FIG. 12, a first thermoelectric module M1 is composed of the first thermoelectric elements 34a, and the first thermoelectric elements 34a are electrically connected to the first in series via a bonding metal such as solder. The lower electrode 33a is between the lower electrode 35a and the second upper electrode 35a. In addition, a second thermoelectric module M2 is composed of the second thermoelectric elements 34b, and the second thermoelectric elements 34b are electrically connected in series to the first upper electrodes 33b and a second via a bonding metal such as solder. Between the two lower electrodes 35b.

The heat exchangers 31, 36 and 38 (acting as water-cooling fins) are each composed of aluminum or an aluminum alloy having a high thermal conductivity, wherein the surface and the back surface of the first heat exchanger 31 (adjacent to the insulating layers 32a and 32b) are adjacent The surface of the second heat exchanger 36 of the insulating layer 37 and the surface of the third heat exchanger 38 (next to the insulating layer 39) are each trimmed to have a surface roughness Ra of 5 μm or less. Further, a plurality of passages 31a (allowing a cooling medium, that is, water, flowing in a specified direction, that is, from right to left) are formed in the first heat exchanger 31. Similarly, a plurality of channels 36a are formed in the second heat exchanger 36, and a plurality of channels 38a are formed in the third heat exchanger 38. Here, the cavity or depression is formed on the surface of the heat exchangers 31, 36 and 38 subjected to molding (or casting) using a tool. For this reason, the bypass regions 31c, 36c, and 38c are formed to prevent the electrodes 33a, 33b, 35a, and 35b from being formed on the surfaces of the heat exchangers 31, 36, and 38 as shown in Figs. 11A and 11B. Further, a plurality of mounting holes 31b, 36b, and 38b are formed at the corners of the heat exchangers 31, 36, and 38.

The insulating layers 32a, 32b, 37, and 39 are each composed of a polyimide resin, an epoxy resin, or an alumite, and the insulating layers have a thickness of 10 μm to 100 μm. Preferably, a filler composed of alumina (Al ₂ O ₃ ), aluminum nitride (AlN), magnesium oxide (MgO) or tantalum carbide (SiC) having an average particle diameter of 15 μm or less is dispersed to the polyruthenium. The insulating layer 32a, 32b, 37, and 39 composed of an amine resin or an epoxy resin improves the thermal conductivity. Further, it is preferable to laminate a polyimine resin or an epoxy resin in which a filler is dispersed on the insulating layers 32a, 32b, 37 and 39 composed of alumite.

The electrodes 33a, 33b, 35a, and 35b are each composed of a copper film or a copper alloy film having a thickness of 70 μm to 200 μm. Each of the first lower electrode 33a and the first upper electrode 33b has an alignment pattern shown in FIG. 11A, and each of the second upper electrode 35a and the second lower electrode 35b has the same in FIG. 11B. One of the shown alignment patterns. Each of the segments of the electrodes 33a, 33b, 35a, and 35b is formed into a rectangular shape having a length of 3 mm and a short length of 1.8 mm. Additionally, the minimum distance t between adjacent segments is shorter than the short length (eg, 1.8 mm) of each rectangular segment.

The first thermoelectric elements 34a composed of a P-type semiconductor and an N-type semiconductor are electrically connected in series to the first lower electrode 33a and the second upper electrode 35a in such a manner that the P-type semiconductor and the N-type semiconductor are alternately aligned. between. Similarly, the second thermoelectric elements 34b composed of a P-type semiconductor and an N-type semiconductor are electrically connected in series to the first upper electrode 33b and the second lower electrode in such a manner that the P-type semiconductor and the N-type semiconductor are alternately aligned. Between 35b. The thermoelectric elements 34a and 34b are soldered to the electrodes 33a, 33b, 35a, and 35b via a SnSb alloy, an AuSn alloy, or a SnAgCu alloy. The distal ends of the thermoelectric elements 34a and 34b are plated with nickel so that the thermoelectric elements 34a and 34b can be easily soldered to the electrodes 33a, 33b, 35a and 35b.

The thermoelectric elements 34a and 34b are preferably composed of a sintered thermoelectric material of Bi-Te having high thermoelectric efficiency at room temperature. Specifically, a P-type semiconductor composed of a ternary compound of Bi-Sb-Te and an N-type semiconductor composed of a quaternary compound of Bi-Sb-Te-Se are preferably used. In the current embodiment, the P-type semiconductor is composed of Bi _0.5 Sb _1.5 Te ₃ and the N-type semiconductor is composed of Bi _1.9 Sb _0.1 Te _2.6 Se _0.4 , wherein the semiconductors are subjected to liquid quenching to produce foil powder, and the foil powder is then The heat is pressed to form a block which is then cut into small pieces each having a specified size of 1.35 mm long, 1.35 mm wide, and 1.5 mm high.

(a) Manufacturing of heat exchange unit 30

The heat exchange unit 30 is manufactured by the following procedure.

First, the first heat exchanger 31 (serving as an endothermic water-cooling fin) is prepared such that the adhesive insulating layers 32a and 32b are formed on the surface and the back surface of the heat exchanger, and a plurality of channels 31a are formed therein. The heat exchanger is configured to allow a cooling medium (i.e., water) to flow through the passages. A second heat exchanger 36 (serving as a heat-dissipating water-cooling fin) is prepared such that an adhesive insulating layer 37 is formed on the surface of the heat exchanger, and a plurality of channels 36a are formed in the heat exchanger to allow A cooling medium (i.e., water) flows through the channels. A third heat exchanger 38 (serving as a heat-dissipating water-cooling fin) is prepared such that an adhesive insulating layer 39 is formed on the surface of the heat exchanger, and a plurality of channels 38a are formed in the heat exchanger to allow A cooling medium (i.e., water) flows through the channels. Further, the first lower electrode 33a, the first upper electrode 33b, the second upper electrode 35a, and the second lower electrode 35b are prepared in advance. Further, the thermoelectric elements 34a and 34b composed of a P-type semiconductor and an N-type semiconductor are prepared in advance.

The heat exchangers 31, 36 and 38 are each composed of aluminum or an aluminum alloy having a high thermal conductivity. The surface and the back surface of the first heat exchanger 31 (adjacent to the insulating layers 32a and 32b), the surface of the second heat exchanger 36 (which is adjacent to the insulating layer 37), and the third heat exchanger 38 (next to the insulating layer 39) The surfaces are each trimmed to have a surface roughness Ra of 5 μm or less. The insulating layers 32a, 32b, 37, and 39 are formed by dispersing a filler composed of Al ₂ O ₃ , AlN, MgO, or SiC into an adhesive polyimide or epoxy layer. Alternatively, the insulating layers are formed using a composite layer in which a polyimine resin layer or an epoxy layer in which a filler is dispersed is formed on the alumite layer. Here, the insulating layers 32a, 32b, 37, and 39 are formed by crimping the material of the sheet shape. Alternatively, the varnish is applied to a sheet-shaped material, which is then cured to form insulating layers 32a, 32b, 37, and 39. The electrodes 33a, 33b, 35a, and 35b are each composed of a copper film or a copper alloy film and are each formed to define a predetermined electrode pattern having a specified thickness of 70 μm to 200 μm. The far end (or the opposite end in the longitudinal direction) of the P-type semiconductor and the N-type semiconductor is plated with nickel.

As shown in FIG. 10A, a first lower electrode 33a composed of a copper film or a copper alloy film having the specified electrode pattern shown in FIG. 11A is bonded to the insulating layer 32a of the first heat exchanger 31. The first upper electrode 33b composed of a copper film or a copper alloy film having the specified electrode pattern shown in Fig. 11A is bonded to the insulating layer 32b of the first heat exchanger 31. Subsequently, as shown in FIG. 10B, the thermoelectric elements 34a composed of a P-type semiconductor and an N-type semiconductor are alternately aligned on the first lower electrode 33a, wherein the lower ends of the thermoelectric elements 34a are via a solder alloy (for example The SnSb alloy, the AuSn alloy, and the SnAgCu alloy are attached to the first lower electrode 33a. The second thermoelectric elements 34b composed of a P-type semiconductor and an N-type semiconductor are alternately aligned under the first upper electrode 33b, wherein the upper ends of the thermoelectric elements 34b are via a solder alloy (for example, SnSb alloy, AuSn alloy, and The SnAgCu alloy is attached to the first upper electrode 33b. A second upper electrode 35a composed of a copper film or a copper alloy film having a specified electrode pattern (see FIG. 11B) is disposed on the upper ends of the first thermoelectric elements 34a to have a specified electrode pattern (see FIG. 11B). A second lower electrode 35b composed of a copper film or a copper alloy film is disposed under the lower ends of the second thermoelectric elements 34b.

Thereafter, the second upper electrode 35a is attached to the upper ends of the first thermoelectric elements 34a via a solder alloy (for example, a SnSb alloy, an AuSn alloy, and a SnAgCu alloy), and the second lower electrode 35b is attached to the first lower electrodes 35b. The lower end of the second thermoelectric element 34b. Therefore, the first thermoelectric elements 34a composed of a P-type semiconductor and an N-type semiconductor are alternately aligned and electrically connected in series between the first lower electrode 33a and the second upper electrode 35a, and the P-type semiconductor and The second thermoelectric elements 34b composed of N-type semiconductors are alternately aligned and electrically connected in series between the first upper electrode 33b and the second lower electrode 35b.

Finally, as shown in FIG. 10C, the insulating layer 37 of the second heat exchanger 36 is brought into contact with the second upper electrode 35a while the insulating layer 39 of the third heat exchanger 38 is brought into contact with the second lower electrode 35b; thereafter, The second upper electrode 35a is bonded to the insulating layer 37 while the second lower electrode 35b is bonded to the insulating layer 39. This completes the manufacture of the heat exchange unit 30 of the third embodiment.

(b) Use of heat exchange unit 30

The heat exchange unit 30 of the third embodiment can be used to control the temperature of a specified object (i.e., a body that requires temperature control, not shown). For example, hot water warmed by absorbing heat from the specified object is supplied to the inlet of the passage 31a of the "endothermic" first heat exchanger 31, and the outlet of the passage 31a is connected to the designated object. Further, cold water is supplied to the inlet of the passage 36a of the second heat exchanger 36 and the inlet of the passage 38a of the third heat exchanger 38, and the outlets of the passages 36a and 38a are used as the drain.

In the above state, electricity is applied to the first thermoelectric module M1, wherein the first thermoelectric elements 34a are electrically connected in series to the "heat-dissipating" second upper electrode 35a and the "endothermic" first lower electrode 33a. Between the first lower electrode 33a is cooled to absorb heat from the hot water supplied to the designated object via the "endothermic" first heat exchanger 31, and the second upper electrode 35a is heated so that its heat flows through the flow. The cold water passing through the passage 36a of the second heat exchanger 36 is dissipated.

Applying electricity to the second thermoelectric module M2, wherein the second thermoelectric elements 34b are electrically connected in series between the "heat-dissipating" second lower electrode 35b and the "endothermic" first upper electrode 33b, thereby being first The upper electrode 33b is cooled to absorb heat from the hot water supplied to the specified article via the first heat exchanger 31, and the second lower electrode 35b is heated such that its heat passes through the passage 38a of the third heat exchanger 38. Cold water is dissipated.

(c) Measurement of the maximum endothermic value Qmax

Using the heat exchange unit 30 of the third embodiment, it is possible to measure the maximum heat-absorption or endothermic value Qmax constituting a performance evaluation reference by the following procedure. Test examples F1, F2 and G1 to G4 were fabricated based on the heat exchange unit 30. As shown in Fig. 12, the heat exchange unit 30 (i.e., test examples F1, F2 and G1-G4 of the heat exchange unit) was placed therein using a vacuum chamber Z.

A hot water pipe (not shown) is connected to the inlet of the passage 31a of the first heat exchanger 31, and a drain pipe (not shown) is connected to the outlet of the passage 31a. A cold water pipe (not shown) is connected to the inlet of the passage 36a of the second heat exchanger 36, and a drain pipe (not shown) is connected to the outlet of the passage 36a. A cold water pipe is connected to the inlet of the passage 38a of the third heat exchanger 38, and a drain pipe is connected to the outlet of the passage 38a.

The heat exchange unit 30 is driven to measure the inlet and outlet temperatures of the passage 31a, the inlet and outlet temperatures of the passage 36a, and the inlet and outlet temperatures of the passage 38a for ten minutes, wherein the inlet temperature is increased by measuring the inlet temperature. The average is used to perform the measurement to estimate the maximum endothermic value Qmax. The measurement results show that the heat exchange unit F1 indicates Qmax = 435W, and the heat exchange unit F2 indicates Qmax = 440W. In addition, the heat exchange unit G1 indicates Qmax=432W, the heat exchange unit G2 indicates Qmax=434W, the heat exchange unit G3 indicates Qmax=430W, and the heat exchange unit G4 indicates Qmax=430W.

In the above, the heat exchange unit F1 is manufactured such that a filler composed of alumina (Al ₂ O ₃ ) powder is dispersed in the polyimide film to form an insulating layer 32a, 32b, 37 having a thickness of 15 μm and 39. The heat exchange unit F2 was fabricated such that a filler composed of alumina powder was dispersed in the lacquered polyimide resin to form insulating layers 32a, 32b, 37, and 39 having a thickness of 20 μm.

The heat exchange unit G1 is fabricated such that a filler composed of aluminum oxide (Al ₂ O ₃ ) powder and aluminum nitride (AlN) powder is dispersed in an epoxy resin sheet on a 10 μm thick alumite layer, thereby forming 20 μm thick insulating layers 32a, 32b, 37 and 39. The heat exchange unit G2 is fabricated such that a filler composed of aluminum oxide (Al ₂ O ₃ ) powder and aluminum nitride (AlN) powder is dispersed in a painted epoxy resin on a 10 μm thick alumite layer to form The insulating layers 32a, 32b, 37, and 39 have a thickness of 20 μm. The heat exchange unit G3 was fabricated such that a filler composed of aluminum oxide (Al ₂ O ₃ ) powder and magnesium oxide (MgO) powder was dispersed in an epoxy resin sheet on a 10 μm thick alumite layer to form 20 μm. Insulating layers 32a, 32b, 37 and 39 of thickness. Manufacturing a heat exchange unit G4 such that a filler composed of alumina (Al ₂ O ₃ ) powder and cerium carbide (SiC) powder is dispersed in a lacquer epoxy resin on a 10 μm thick alumite layer, thereby forming 20 μm thick insulating layers 32a, 32b, 37 and 39.

(d) Measurement of withstand voltage WS

Based on the heat exchange units F1 and F2, by changing the surface of the first heat exchanger 31 adjacent to the insulating layers 32a and 32b and the surface of the second heat exchanger 36 adjacent to the insulating layer 37 and adjacent to the insulating layer 39 The surface roughness Ra on the surface of the triple heat exchanger 38 is used to manufacture the heat exchange units F11 to F19 and F21 to F29. The withstand voltage WS is measured with respect to the heat exchange units F11-F19 and F21-F29 using different values of the surface roughness Ra.

Specifically, it is changed with respect to the heat exchange unit F1 (on the surface and the back surface of the first heat exchanger 31 adjacent to the insulating layers 32a and 32b, on the surface of the second heat exchanger 36 adjacent to the insulating layer 37, and adjacent to the insulating layer 39 The surface roughness Ra on the surface of the third heat exchanger 38 is such that the heat exchange unit F11 has a surface roughness of 0.3 μm, the heat exchange unit F12 has a surface roughness of 0.5 μm, and the heat exchange unit F13 has a thickness of 1.0 μm. Surface roughness, heat exchange unit F14 has a surface roughness of 1.6 μm, heat exchange unit F15 has a surface roughness of 2.2 μm, heat exchange unit F16 has a surface roughness of 3.2 μm, and heat exchange unit F17 has a surface roughness of 4.4 μm. The heat exchange unit F18 has a surface roughness of 4.7 μm, and the heat exchange unit F19 has a surface roughness of 5.1 μm. Further, a heat exchange unit F1a having a surface roughness of 0.08 μm and a heat exchange unit F1b having a surface roughness of 0.1 μm were produced based on the heat exchange unit F1, and the withstand voltage WS was measured. The measurement results are shown in Table 6-1, in which the insulating layers 32a, 32b, 37, and 39 are each configured of a 15 μm thick polyimide film, and the filler is composed of alumina (Al ₂ O ₃ ).

Further, the surface roughness Ra is changed with respect to the heat exchange unit F2 so that the heat exchange unit F21 has a surface roughness of 0.3 μm, the heat exchange unit F22 has a surface roughness of 0.5 μm, and the heat exchange unit F23 has a surface roughness of 1.0 μm. The heat exchange unit F24 has a surface roughness of 1.6 μm, the heat exchange unit F25 has a surface roughness of 2.2 μm, the heat exchange unit F26 has a surface roughness of 3.2 μm, and the heat exchange unit F27 has a surface roughness of 4.4 μm, heat. The exchange unit F28 has a surface roughness of 4.7 μm, and the heat exchange unit F29 has a surface roughness of 5.1 μm. Further, a heat exchange unit F2a having a surface roughness of 0.08 μm and a heat exchange unit F2b having a surface roughness of 0.1 μm were produced based on the heat exchange unit F2, and the withstand voltage WS was measured. The measurement results are shown in Table 6-2, in which the insulating layers 32a, 32b, 37, and 39 are each configured by a 20 μm thick polyimide varnish, and the filler is composed of alumina (Al ₂ O ₃ ).

The measurement results of the heat exchange units F11-F19 and F21-F29 in Tables 6-1 and 6-2 are plotted on the graph of Fig. 13, and the horizontal axis of the graph of Fig. 13 indicates the surface roughness Ra ( Μm) and the vertical axis of the graph of Fig. 13 represents the withstand voltage WS(kV), thereby plotting the measurement curves (or broken lines) F1 and F2. The above measurement results shown in FIG. 13 and Table 6-1 and Table 6-2 clearly show that the withstand voltage WS is good when the surface roughness Ra is less than 4.7 μm, but when the surface roughness Ra exceeds 4.7 μm. The surface roughness Ra of the heat exchangers 31, 36 and 38 is preferably less than 4.7 μm.

Similarly, based on the heat exchange units G1, G2, G3, and G4, the surface of the second heat exchanger 36 adjacent to the insulating layer 37 on the front and back surfaces of the first heat exchanger 31 adjacent to the insulating layers 32a and 32b is changed. The surface roughness Ra on the surface of the third heat exchanger 38 adjacent to the insulating layer 39 is used to manufacture the heat exchange units G11 to G19, G21 to G29, G31 to G39, and G41 to G49. The withstand voltage WS is measured with respect to the heat exchange units G11-G19, G21-G29, G31-G39, and G41-G49 using different values of the surface roughness Ra.

Specifically, it is changed with respect to the heat exchange unit G1 (on the surface and the back surface of the first heat exchanger 31 adjacent to the insulating layers 32a and 32b, on the surface of the second heat exchanger 36 adjacent to the insulating layer 37, and adjacent to the insulating layer 39 The surface roughness Ra on the surface of the third heat exchanger 38 is such that the heat exchange unit G11 has a surface roughness of 0.3 μm, the heat exchange unit G12 has a surface roughness of 0.5 μm, and the heat exchange unit G13 has a thickness of 1.0 μm. Surface roughness, heat exchange unit G14 has a surface roughness of 1.6 μm, heat exchange unit G15 has a surface roughness of 2.1 μm, heat exchange unit G16 has a surface roughness of 3.2 μm, and heat exchange unit G17 has a surface roughness of 4.4 μm. The heat exchange unit G18 has a surface roughness of 4.7 μm, and the heat exchange unit G19 has a surface roughness of 5.1 μm. Further, a heat exchange unit G1a having a surface roughness of 0.07 μm and a heat exchange unit G1b having a surface roughness of 0.1 μm were produced based on the heat exchange unit G1, and the withstand voltage WS was measured. The measurement results are shown in Table 7-1, in which the insulating layers 32a, 32b, 37, and 39 are each configured of a 20 μm thick epoxy sheet plus a 10 μm alumite layer, and the filler is made of alumina (Al _{2 ).} O ₃ ) plus aluminum nitride (AlN) composition.

The surface roughness Ra is changed with respect to the heat exchange unit G2 such that the heat exchange unit G21 has a surface roughness of 0.3 μm, the heat exchange unit G22 has a surface roughness of 0.5 μm, and the heat exchange unit G23 has a surface roughness of 1.0 μm, heat The exchange unit G24 has a surface roughness of 1.6 μm, the heat exchange unit G25 has a surface roughness of 2.1 μm, the heat exchange unit G26 has a surface roughness of 3.2 μm, and the heat exchange unit G27 has a surface roughness of 4.4 μm, and the heat exchange unit G28 has a surface roughness of 4.7 μm, and the heat exchange unit G29 has a surface roughness of 5.1 μm. Further, a heat exchange unit G2a having a surface roughness of 0.07 μm and a heat exchange unit G2b having a surface roughness of 0.1 μm were produced based on the heat exchange unit G2, and the withstand voltage WS was measured. The measurement results are shown in Table 7-2, in which the insulating layers 32a, 32b, 37 and 39 are each configured by a 20 μm thick epoxy varnish plus a 10 μm alumite layer, and the filler is made of alumina (Al ₂ O ₃ ) plus aluminum nitride (AlN) composition.

The surface roughness Ra is changed with respect to the heat exchange unit G3 such that the heat exchange unit G31 has a surface roughness of 0.3 μm, the heat exchange unit G32 has a surface roughness of 0.5 μm, and the heat exchange unit G33 has a surface roughness of 1.0 μm, heat The exchange unit G34 has a surface roughness of 1.6 μm, the heat exchange unit G35 has a surface roughness of 2.1 μm, the heat exchange unit G36 has a surface roughness of 3.2 μm, and the heat exchange unit G37 has a surface roughness of 4.4 μm, and the heat exchange unit G38 has a surface roughness of 4.7 μm, and the heat exchange unit G39 has a surface roughness of 5.1 μm. Further, a heat exchange unit G3a having a surface roughness of 0.07 μm and a heat exchange unit G3b having a surface roughness of 0.1 μm were produced based on the heat exchange unit G3, and the withstand voltage WS was measured. The measurement results are shown in Table 7-3, in which the insulating layers 32a, 32b, 37, and 39 are each configured of a 20 μm thick epoxy sheet plus a 10 μm alumite layer, and the filler is made of alumina (Al ₂ O ₃ ) plus magnesium oxide (MgO) composition.

The surface roughness Ra is changed with respect to the heat exchange unit G4 such that the heat exchange unit G41 has a surface roughness of 0.3 μm, the heat exchange unit G42 has a surface roughness of 0.5 μm, and the heat exchange unit G43 has a surface roughness of 1.0 μm, heat The exchange unit G44 has a surface roughness of 1.6 μm, the heat exchange unit G45 has a surface roughness of 2.1 μm, the heat exchange unit G46 has a surface roughness of 3.2 μm, the heat exchange unit G47 has a surface roughness of 4.4 μm, and the heat exchange unit G48 has a surface roughness of 4.7 μm, and the heat exchange unit G49 has a surface roughness of 5.1 μm. Further, a heat exchange unit G4a having a surface roughness of 0.07 μm and a heat exchange unit G4b having a surface roughness of 0.1 μm were produced based on the heat exchange unit G4, and the withstand voltage WS was measured. The measurement results are shown in Table 7-4, in which the insulating layers 32a, 32b, 37 and 39 are each configured by a 20 μm thick epoxy varnish plus a 10 μm alumite layer, and the filler is made of alumina (Al ₂ O ₃ ) plus a tantalum nitride (SiC) composition.

The measurement results of the heat exchange units G11-G19, G21-G29, G31-G39, and G41-G49 in Table 7-1 to Table 7-4 are plotted in FIG. 13 to draw a measurement curve (or Broken line) G1, G2, G3 and G4. The above measurement results shown in FIG. 13 and Table 7-1 to Table 7-4 clearly show that the withstand voltage WS is good when the surface roughness Ra is less than 4.7 μm, but when the surface roughness Ra exceeds 4.7 μm. Decrease rapidly. Therefore, the surface roughness Ra of the heat exchangers 31, 36 and 38 is preferably less than 4.7 μm.

According to the heat exchange units A1a-A3a, A1b-A3b, C1a-C3a, C1b-C3b, D1a-D3a, D1b-D3b, E1a-E2a, E1b-E2b, F1a-F2a, F1b-F2b, G1a-G4a and G1b As a result of the additional measurement of -G4b, the maximum endothermic value Qmax is greatly reduced so that the heat absorption/heat dissipation performance is degraded when the surface roughness Ra becomes less than 0.1 μm. This is because, when the surface roughness Ra becomes less than 0.1 μm, the surface of the heat exchanger may act as a mirror surface, which reduces the interface region formed between the insulating layer and the surface of the heat exchanger so that the thermal resistance at the interface region Increasing, the increase in thermal resistance in turn reduces the heat exchange efficiency. Therefore, the surface roughness Ra at the interface between the insulating layer and the heat exchanger is preferably greater than 0.1 μm.

4. Industrial applicability

The above examples were configured using a synthetic resin material such as a polyimide resin and an epoxy resin. Of course, it is possible to use other materials which also exhibit the aforementioned effects, such as an aromatic polyamide resin and a BT (bismaleimide-triazine) resin.

The above embodiment is configured using a filler such as alumina powder, aluminum nitride powder, magnesium oxide powder, and tantalum carbide; however, this is not a limitation; therefore, other filler materials having high thermal conductivity such as carbon powder may be used. , tantalum carbide powder and tantalum nitride. A single filler material may satisfy the above examples, but it is possible to use a mixture of two or more filler materials. In addition, the filler may be formed in any shape such as a spherical shape and a needle shape, and a combination thereof.

In the end, the present invention is not necessarily limited to the above embodiments, and the embodiments may be further modified in various ways within the scope of the invention as defined in the appended claims.

10. . . Heat exchange unit

11. . . First heat exchanger

11a. . . Heat sink fin

12. . . Insulation

13. . . Lower electrode

14. . . Thermoelectric element

15. . . Upper electrode

16. . . Second heat exchanger

16a. . . Heat sink fin

17. . . Insulation

20. . . Heat exchange unit

twenty one. . . First heat exchanger

21a. . . aisle

21b. . . Mounting holes

twenty two. . . Insulation

twenty three. . . Lower electrode

twenty four. . . Thermoelectric element

25. . . Upper electrode

26. . . Second heat exchanger

26a. . . aisle

26b. . . Mounting holes

27. . . Insulation

30. . . Heat exchange unit

31. . . First heat exchanger

31a. . . aisle

31b. . . Mounting holes

31c. . . Bypass area

32a. . . Insulation

32b. . . Insulation

33a. . . First lower electrode

33b. . . First upper electrode

34a. . . First thermoelectric element

34b. . . Second thermoelectric element

35a. . . Second upper electrode

35b. . . Second lower electrode

36. . . Second heat exchanger

36a. . . aisle

36b. . . Mounting holes

36c. . . Bypass area

37. . . Insulation

38. . . Third heat exchanger

38a. . . aisle

38b. . . Mounting holes

38c. . . Bypass area

39. . . Insulation

40. . . Heat exchange unit

40a. . . Thermoelectric module

41. . . Heat exchange unit (heat sink)

42. . . Insulation

43. . . Metal plating

44. . . "lower" metal electrode

45a. . . P type thermoelectric element

45b. . . N type thermoelectric element

46. . . "upper" metal electrode

50. . . Heat exchange unit

50a. . . Thermoelectric converter module (or thermoelectric module)

51. . . Heat sink (or heat sink)

52. . . Heat absorbing part (or heat sink)

53. . . Heat sink electrode

54. . . Endothermic electrode

55. . . Thermoelectric element

56a. . . Resin

56b. . . Metal foil

56c. . . solder

57a. . . Resin

57b. . . grease

A1~A3. . . Test example of heat exchange unit

B1~B4. . . Test example of heat exchange unit

C1~C3. . . Test example of heat exchange unit

D1~D3. . . Test example of heat exchange unit

E1~E2. . . Test example of heat exchange unit

F1~F2. . . Test example of heat exchange unit

G1~G4. . . Test example of heat exchange unit

H. . . Heater

M. . . Thermoelectric module

M1. . . First thermoelectric module

M2. . . Second thermoelectric module

P. . . Probe

X. . . Insulation box

Y. . . Vacuum chamber

Z. . . Vacuum chamber

Figure 1A is a longitudinal cross-sectional view showing a first heat exchanger adjacent to a lower electrode via an insulating layer.

Figure 1B is a longitudinal cross-sectional view in which a plurality of thermoelectric elements are aligned and bonded to the lower electrode of the first heat exchanger.

1C is a longitudinal cross-sectional view, in which a second heat exchanger adjacent to an upper electrode via an insulating layer is combined with the first heat exchanger shown in FIG. 1B, and wherein the thermoelectric elements are inserted in the first A heat exchange unit according to the first embodiment of the present invention is formed between the lower electrode of the heat exchanger and the upper electrode of the second heat exchanger, and includes a thermoelectric module.

2A is a plan view showing an alignment pattern of lower electrodes.

2B is a plan view showing an alignment pattern of the upper electrode.

The explanatory diagram of Fig. 3 shows a heat insulating box for measuring the maximum endothermic value Qmax with respect to the heat exchange unit of the first embodiment.

4 is a diagram showing a method for measuring the withstand voltage WS of the heat exchange unit of the first embodiment.

Fig. 5 is a graph showing the measurement results of the withstand voltage WS with respect to the surface roughness Ra of the test example of the heat exchange unit of the first embodiment.

Fig. 6A is a side view showing the heat exchange unit according to the second embodiment of the present invention, the lower electrode is formed on the surface of a water-cooled first heat exchanger via an insulating layer.

Figure 6B is a side elevational view showing an upper electrode attached to the upper end of the thermoelectric element aligned on the lower electrode of the first heat exchanger shown in Figure 6A.

Figure 6C is a side view showing a water-cooled second heat exchanger adjacent to the upper electrode via an insulating layer.

Fig. 7A is a plan view showing an alignment pattern of lower electrodes.

Fig. 7B is a plan view showing an alignment pattern of the upper electrode.

The explanatory diagram of Fig. 8 shows a vacuum chamber for measuring the maximum endothermic value Qmax with respect to the heat exchange unit of the second embodiment.

Fig. 9 is a graph showing the measurement results of the withstand voltage WS with respect to the surface roughness Ra of the test example of the heat exchange unit of the second embodiment.

10A is a side view showing a heat exchange unit according to a third embodiment of the present invention, a first lower electrode and a first upper electrode are formed on the surface and the back surface of a water-cooled first heat exchanger via an insulating layer. on.

Figure 10B is a side view showing a second upper electrode attached to the upper end of the first thermoelectric element aligned on the first lower electrode and a second lower electrode attached to the underlying first upper electrode The lower end of the second thermoelectric element.

Figure 10C is a side view showing a water-cooled second heat exchanger adjacent to the second upper electrode via an insulating layer and a water-cooled third heat exchanger adjacent the second lower electrode.

Figure 11A is a plan view showing an alignment pattern of a first lower electrode and a first upper electrode.

Fig. 11B is a plan view showing an alignment pattern of the second lower electrode and the second upper electrode.

Figure 12 is an explanatory view showing a vacuum chamber for measuring the maximum endothermic value Qmax with respect to the heat exchange unit of the third embodiment.

Fig. 13 is a graph showing the measurement results of the withstand voltage WS with respect to the surface roughness Ra of the test example of the heat exchange unit of the third embodiment.

Figure 14 is a longitudinal cross-sectional view showing an example of a heat exchange unit.

Figure 15 is a longitudinal cross-sectional view showing another example of a heat exchange unit.

10. . . Heat exchange unit

11. . . First heat exchanger

11a. . . Heat sink fin

12. . . Insulation

13. . . Lower electrode

14. . . Thermoelectric element

15. . . Upper electrode

16. . . Second heat exchanger

16a. . . Heat sink fin

17. . . Insulation

Claims (10)

A heat exchange unit comprising: an upper electrode; a lower electrode; a plurality of thermoelectric elements interposed between the upper electrode and the lower electrode; and a heat exchanger attached to the upper electrode via an insulating layer Or the lower electrode, wherein the heat exchanger is composed of a metal having a high thermal conductivity, and a surface roughness of the heat exchanger adjacent to the insulating layer is less than 4.7 μm; the surface of the heat exchanger adjacent to the insulating layer The roughness is greater than 0.1 μm; and the insulating layer has a thickness of 10 μm to 100 μm. The heat exchange unit of claim 1, wherein the heat exchanger is composed of aluminum or an aluminum alloy. The heat exchange unit of claim 1, wherein the insulating layer is composed of an insulating resin layer having a high thermal conductivity. The heat exchange unit of claim 1, wherein the insulating layer is a composite layer, and an insulating resin layer having a high thermal conductivity is laminated on an alumite layer. The heat exchange unit of claim 1, wherein the insulating layer is composed of a polyimide resin or an epoxy resin. The heat exchange unit of claim 1, wherein the insulating layer is composed of a lacquered polyimide resin or a lacquered epoxy resin. The heat exchange unit of claim 1, wherein the insulating layer is composed of an insulating resin in which a filler having a high thermal conductivity is dispersed. The heat exchange unit of claim 1, wherein the insulating layer is composed of a varnish insulating resin in which a filler having a high thermal conductivity is dispersed. The heat exchange unit of claim 7, wherein the filler is composed of alumina powder, aluminum nitride powder, magnesium oxide powder or tantalum carbide powder. The heat exchange unit of claim 8, wherein the filler is composed of alumina powder, aluminum nitride powder, magnesium oxide powder or tantalum carbide powder.