CN101320781A - Thermoelectric conversion device - Google Patents

Abstract

Provided is a thermoelectric conversion device with high reliability, the thermoelectric conversion device (1) has a plurality of p-type thermoelectric elements (10) and n-type thermoelectric elements (11), and the position where each thermoelectric element (10, 11) should be arranged A plurality of heat-dissipating-side electrodes (13) correspondingly arranged are arranged in a matrix on the surface of a plane-forming heat-dissipating-side substrate (14), and a plurality of p-type thermoelectric elements (10) and a plurality of n-type thermoelectric elements ( 11) While sliding the heat-absorbing-side electrodes (5) on the heat-absorbing-side end surfaces of these thermoelectric elements, the heat-dissipating-side end surfaces of the respective thermoelectric elements (10, 11) and the heat-discharging-side electrodes (13) utilize Solder (12) for joining.

Description

Thermoelectric conversion device

This application is a divisional application of the patent application with the application number 200410095162.4, the application date is July 23, 2004, and the invention name is "thermoelectric conversion device".

technical field

The present invention relates to a heat-absorbing-side electrode installed on the heat-absorbing surface of a plurality of thermoelectric elements, and a heat-discharging-side electrode is installed on the heat-dissipating surface of each thermoelectric element, and all the thermoelectric elements are electrically connected in series and thermally connected in parallel. The conversion device, in particular, relates to a thermoelectric conversion device with good manufacturability and excellent bonding reliability.

Background technique

Thermoelectric conversion devices are composed of thermoelectric elements utilizing thermoelectric effects such as the Thomson effect, Pelty effect, and Seebeck effect, and have been mass-produced as a temperature adjustment unit that converts electricity into heat. In addition, as a power generation unit, its research and development is gradually advancing.

A thermoelectric conversion device as a power generation unit has a plurality of thermoelectric elements spaced apart on an insulating substrate having electrodes, electrically connected in series and thermally connected in parallel.

In order to bring the power generation efficiency of the thermoelectric conversion device close to that of the thermoelectric element itself, it is necessary to smoothly supply heat to one end of the thermoelectric element and release heat from the other end of the thermoelectric element. Therefore, a ceramic substrate excellent in heat conduction is used as a substrate constituting the thermoelectric conversion device. In addition, the electrodes disposed on the ends of the thermoelectric elements are made of a material with low electrical resistance.

Contents of the invention

As described above, by heating, the thermoelectric conversion device operates, and at the same time, each structural member thermally expands compared to normal temperature. At this time, the amount of deformation in each member differs depending on the difference in the coefficient of linear expansion of each structural member and the temperature difference between the heat-absorbing side and the heat-releasing side. Due to the difference in the amount of thermal deformation, the joint portion of the thermoelectric element and the thermoelectric element may be easily damaged.

In order to solve the above-mentioned problems, an object of the present invention is to provide a thermoelectric element conversion device and a manufacturing method thereof which are highly reliable and are hardly damaged even if the thermoelectric device is thermally deformed by heating.

In order to solve the above-mentioned problems, the present invention provides a thermoelectric conversion device comprising: a wiring board; a plurality of thermoelectric elements, one end surface of which is fixed and vertically provided on the wiring board; The other end surface of the above-mentioned thermoelectric element is in contact; a cover portion that holds a plurality of the above-mentioned thermoelectric elements and a plurality of the above-mentioned electrode parts by being configured to apply pressure in a direction from one end surface of the above-mentioned thermoelectric element to the other end surface; a bonding member The relative position of the said wiring board and the said cover part is maintained.

In this case, it is preferable that the electrode member is provided so as to surround a region where the thermoelectric element is crimped and to limit the position of the thermoelectric element.

In addition, the above-mentioned electrode member is preferably arranged in series with the above-mentioned thermoelectric element.

Furthermore, it is preferable to have a deformable structural member made of a conductive material provided between the thermoelectric element and the electrode member.

In addition, it is preferable that an insulating member for defining the position of the thermoelectric elements is arranged between the above-mentioned thermoelectric elements arranged separately.

In addition, it is preferable that the interval between the thermoelectric elements surrounded by the electrode members is shorter than the interval between the thermoelectric elements and the thermoelectric elements surrounded by the electrode members adjacent to the electrode members.

In addition, the bonding member is bonded to the wiring board with solder, and it is preferable that the bonding surface of the bonding member with the solder is formed in a chamfered shape.

Furthermore, it is preferable that a folded portion that is folded outward is provided on a portion of the coupling member that is in contact with the lid portion.

In addition, it is preferable to provide a bent portion bent in a direction in which pressure is applied to the above-mentioned cover portion.

According to the thermoelectric conversion device of the present invention, it is possible to provide a thermoelectric conversion device having a simple structure and high reliability during operation.

Description of drawings

FIG. 1 is a cross-sectional view showing an embodiment of a thermoelectric conversion device according to the present invention.

FIG. 2 is a process diagram illustrating a method of manufacturing the thermoelectric conversion device according to the present invention.

3 is a process diagram illustrating a method of manufacturing the thermoelectric conversion device according to the present invention.

4 is a process diagram illustrating a method of manufacturing the thermoelectric conversion device according to the present invention.

5 is a process diagram showing a method of manufacturing the thermoelectric conversion device according to the present invention.

6 is a process diagram illustrating a method of manufacturing the thermoelectric conversion device according to the present invention.

7 is a cross-sectional view showing another embodiment of the thermoelectric conversion device according to the present invention.

8 is a cross-sectional view showing another embodiment of the thermoelectric conversion device according to the present invention.

9 is a cross-sectional view showing another embodiment of the thermoelectric conversion device according to the present invention.

10 is a cross-sectional view showing another embodiment of the thermoelectric conversion device according to the present invention.

11 is a cross-sectional view showing another embodiment of the thermoelectric conversion device according to the present invention.

12 is a cross-sectional view showing another embodiment of the thermoelectric conversion device according to the present invention.

Detailed ways

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram showing a cross-sectional structure of an embodiment of a thermoelectric conversion device according to the present invention. Thermoelectric conversion device 1 has a plurality of p-type thermoelectric elements 10 and n-type thermoelectric elements 11 . A plurality of radiation-side electrodes 13 arranged corresponding to the positions where the respective thermoelectric elements 10 and 11 are to be arranged are arranged in a matrix on the surface of the radiation-side substrate 14 forming a plane. Regarding the plurality of p-type thermoelectric elements 10 and the plurality of n-type thermoelectric elements 11 , the end faces of these thermoelectric elements on the heat release side and the heat release side electrodes 13 are joined by solder 12 .

A heat-absorbing insulating substrate 4 , a heat-absorbing electrode 5 , and a metal fine wire mesh 6 as a mesh structural member are disposed on the heat-absorbing end faces of the respective thermoelectric elements 10 and 11 . The metal fine wire mesh 6 is a conductive member configured to elastically deform in the thickness direction. The heat-absorbing end surface of the thermoelectric element is in contact with the thin metal wire mesh 6 in a state where pressure is applied. With such a structure, the variation in the height of the thermoelectric element is absorbed by the fine metal wire mesh, and stable conduction can be obtained. The fine metal wire mesh 6 is arranged to straddle the heat-absorbing side end faces of a set of thermoelectric elements 10 and 11 . The heat-absorbing-side electrode 5 having a tub-like box-like structure is disposed so as to cover the thin metal wire mesh 6 . By making it into a tub shape, it is difficult to detach the metal fine wire mesh from the thermoelectric element, and at the same time, the surface of the bottom portion constituting the plane faces the heat-radiating side insulating substrate, so that it can be compared with the case of contacting with a mesh structure. Enlarging the contact area helps to increase heat absorption efficiency.

In addition, it contributes to lowering the resistance of the electrode member compared to a structure in which only thin wires are braided. A copper layer is individually provided on the area where the heat-absorbing-side insulating substrate 4 and the heat-absorbing electrode 5 are in contact with each other. In addition, a copper layer is provided on the entire surface of the main surface opposite to the main surface that is in contact with the heat-absorbing electrode, thereby improving the heat-absorbing efficiency and preventing the heat-absorbing-side substrate 4 from warping. This has the effect that warping does not occur on the heat-absorbing-side substrate 4 when the entire thermoelectric conversion device is put into the furnace to solder the frame 9 to the heat-emitting-side substrate 14 .

The heat-absorbing-side insulating substrate 4, the heat-absorbing-side electrode 5, and the metal thin-wire mesh 6 as a mesh structural member are held and sandwiched by the cover 2 and the heat-releasing side substrate 14 in the longitudinal direction of the thermoelectric element, that is, with the generation of electromotive force. And the direction of the flowing current exerts pressure. That is, the cover 2 and the heat radiation-side substrate 14 are arranged in a spaced and opposing shape with the thermoelectric elements 10 and 11 interposed therebetween. The thermoelectric conversion device 1 is composed of a cover 2 , a frame 9 , and a heat radiation-side substrate 14 to form a sealed box-shaped structure. The inside of the box-shaped structure is set in a decompressed atmosphere so that the structure is hardly deformed and broken even if a large temperature change is applied. In order to maintain this atmosphere, the thermoelectric elements 10, 11 are sealed with the box-shaped structure.

The electromotive force generated in the thermoelectric elements 10 and 11 is taken out to the outside through the through-hole 16 formed through the inside of the heat radiation-side substrate 14 . External wiring 18 , which is wired on an insulating substrate, is connected to the portion exposed on the main surface on the outside of the through hole 16 by solder 17 . In addition, on the outer surface of the heat radiation side substrate 14, a metal coating film 15 for improving heat radiation is formed.

In the present embodiment, p-type and n-type thermoelectric elements having a scuteldite structure are used as thermoelectric elements in order to set the operating temperature of the high-temperature side of the thermoelectric conversion device to 600°C. The p-type and n-type are configured so that the direction of current generation during heating is opposite to the direction of the thermal gradient. By connecting the p-type and n-type thermoelectric elements 10, 11 in series with the heat-releasing electrode 13 and the heat-absorbing electrode 5, the voltage of the electromotive force is boosted. That is, a current is taken out from the external wiring 18 through the p-type thermoelectric element 10 and the n-type thermoelectric element 11 alternately.

The thermoelectric element conversion device of this embodiment is manufactured by the following steps, for example.

As shown in FIG. 2 , solder 12 is supplied from a dispenser to the portion joined to the thermoelectric element of the heat radiation side electrode 13 on the heat radiation side substrate 14 having the heat radiation side electrode 13 formed on the planar main surface. In this embodiment, since the operating temperature of the heat release side of the thermoelectric element conversion device is set to 200°C, the heat release side electrode 13 uses copper, and the heat release side substrate 14 uses a ceramic substrate made of an Al ₂ O ₃ base material. , The composition of solder 12 uses a solder paste of Pb-8wt%Sn-2wt%Ag. In addition, in the case of this embodiment, as a joining member of the solder material which replaces the solder 12, as long as the melting point is 200 degreeC or more, it can use it, and it does not specifically limit.

The frame 9 is a ceramic substrate made of an Al ₂ O ₃ base material, and the frame 9 and the heat radiation side substrate 14 are bonded with the solder 8 . As the solder, silver solder was used. In addition, in order to perform welding described later on the upper surface of the frame 9 , Kovar 7 , which is the same material as that of the cover 2 , is further brazed on the upper surface of the brazing filler metal 8 .

In addition, the base material of the frame 9 and the heat release side substrate 14 should be selected in consideration of the balance of heat dissipation efficiency, heat insulation performance and airtight performance, but if the combination does not significantly reduce the power generation performance of the thermoelectric conversion device, it can be used . In addition, the brazing filler metal 8 is not particularly limited as long as the bonding strength is hardly lowered at a predetermined operating temperature of the thermoelectric conversion device and the bonded state between ceramics and ceramics can be maintained. In addition, instead of the structure of the soldering frame 9 and the heat radiation side board|substrate 14, it can be comprised as a bathtub-shaped box-shaped structure of course.

On the end faces of the thermoelectric elements 10 and 11 on the heat release side, a Cu thin film was formed in order to improve the bondability between the solder 12 and the thermoelectric elements 10 and 11 . After forming a film of 2 μm by Cu sputtering and forming a film of 18 μm by electroplating, the entire film thickness of the thin film became 20 μm. In addition, it is preferable that the bonding material is changed according to the use temperature. In addition, the end surface treatment of the thermoelectric element is not particularly limited as long as it hardly damages the performance of the thermoelectric element and can improve the connectivity with the bonding material.

As shown in FIG. 3 , the assembly jig 20 has a structure that respectively defines the relative positions where the end faces of the thermoelectric elements 10 and 11 should exist. 10, 11, determine the mutual relative positions of the thermoelectric elements 10, 11, reverse the heat release side substrate 14 shown in Fig. On the end surface of the hot side, it becomes the state shown in FIG. 4 . That is, the heat radiation-side electrode 13 is fixed to the heat radiation-side end surface of each thermoelectric element 10 , 11 with the solder 12 .

The solder 12 is melted and bonded by putting it into a reflow furnace and heating it in a fixed state. At this time, in the joint portion formed by the solder 12, the height deviation of the thermoelectric element is absorbed, and the heat-absorbing end faces of the thermoelectric elements 10 and 11 are aligned by the assembly jig 20, and the virtual heat-absorbing end faces formed by the joint surface are formed. The planarity of the plane is improved, and a structure in which sliding contact with the heat-absorbing-side electrode 5 and the cover 2 can be easily realized.

Next, as shown in FIG. 5 , on each of the thermoelectric elements 10 and 11, the metal fine wire mesh 6 and the heat-absorbing side electrode 5 connected to the p-type thermoelectric element 10 and the n-type thermoelectric element 11 are disposed, so that the p-type thermoelectric element 10 and the N-type thermoelectric elements 11 are electrically connected in series, and, as shown in FIG.

Next, a cover 2 is provided to cover the heat-absorbing side insulating substrate 4. The cover 2 is provided with a closed hole 3 having an opening connecting the front and the back, and is welded by Kovar 7 brazed into a frame shape in advance. Cover 2 and Box 9. In the present embodiment, Kovar is used in order to obtain predetermined heat absorption performance in the material of the cover 2 and to reduce the difference in thermal expansion between the frame 9 and the heat release side substrate 14 .

Finally, by placing the thermoelectric conversion device in a decompressed atmosphere, using a laser to melt and seal the closed hole 3, a thermoelectric conversion device with an airtight structure can be obtained.

In addition, the airtightness of the inverter can be improved by passing the wiring taken out from the inverter through the through hole 16 provided in the heat radiation side substrate 14 .

FIG. 7 shows a second embodiment of the thermoelectric conversion device according to the present invention. This thermoelectric conversion device 21 is characterized in that an insulating substrate is not separately prepared, and the cover 2 is in direct contact with the heat-absorbing-side electrode 5 .

Like the first embodiment, the cover 2 is made of metal because it needs to be joined to the frame 9 by welding. At this time, since the heat-absorbing-side electrodes 5 need to be electrically independent, the cover 2 and the heat-absorbing-side electrodes 5 must be electrically insulated. Therefore, an insulating film such as an oxide film is formed on the contact surface of the cover 2 with the heat-absorbing-side electrode 5 . In addition, an insulating film may be formed on the contact surface of the heat-absorbing-side electrode 5 and the cover 2, or an insulating film may be formed on both the cover 2 and the heat-absorbing-side electrode 5, and the structure may be configured. Thermoelectric conversion device.

Compared with the embodiment shown in FIG. 1, the heat-absorbing side insulating substrate 4 can be omitted, so the thermal resistance is small, and the temperature of the heat-absorbing side end surface of the thermoelectric element can be brought close to the temperature of the heat-absorbing object, and the temperature of the heat-absorbing object can be improved. Power generation efficiency of thermoelectric conversion devices.

FIG. 8 shows a third embodiment of the thermoelectric conversion device according to the present invention. This thermoelectric conversion device 22 is characterized in that a connection cover 71 and a heat radiation side substrate are formed by a frame 23 and a frame 24 divided into two in the height direction. 14 boxes. The cover 71 and the heat radiation side substrate 14 are made of ceramics such as Al ₂ O ₃ , and the frame 23 and the frame 24 are welded, so they are made of Kovar, for example.

A cover 71 having a metal portion 72 to which the frame 23 is brazed with silver solder 8 and a heat release-side substrate 14 are fitted on the butting surfaces of the frames 23 and 24. The metal portion 73 of the frame 24 is brazed with the solder 8, and the overlapped portion of the frame 23 and the frame 24 is welded with a laser, and a sealed structure can be realized by melting and plugging the closed hole 3 with a laser under a reduced pressure atmosphere. The metal portions 72 and 73 are formed of, for example, Cu or the like.

In this embodiment, since the frame 23 and the frame 24 are fitted together, when the thermoelectric conversion device is produced, the fitting can be used to absorb the variation in element height and the variation in soldering assembly, etc., and can be easily realized. Sealed structure.

FIG. 9 shows a fourth embodiment of the thermoelectric conversion device according to the present invention. The thermoelectric conversion device 31 is characterized in that the joints between the cover 32 and the heat radiation side substrate 14 at both ends in the height direction are bent. The frame 33 constitutes a frame connecting the cover 32 and the heat radiation-side substrate 14 . The cover 32 and the heat radiation side substrate 14 are made of ceramics such as Al ₂ O ₃ , and the frame 33 is made of a solderable metal such as Kovar.

One end of the frame 33 is joined to the heat radiation-side substrate 14 by soldering with the solder 8 . Forming the rounded shape of the solder on the bent portion of the bent frame 33 contributes to the improvement of joint strength.

On the other hand, joining of the bent portion of the other end portion of the frame 33 and the cover 32 is performed by welding. On the cover 32 , a Kovar ring 35 is brazed to a metal portion 36 made of Cu or the like through a brazing filler metal 8 , and the Kovar ring 35 is welded to the frame 33 . At this time, the end surface of the other end portion faces the outside of the thermoelectric conversion device 31 . This bending process can increase the contact area between the frame 33 and the cover 32 . Laser welding is performed by irradiating the joint interface between the Kovar alloy deposited on the cover 32 and the frame 33 in advance by brazing.

In this way, by bending the joint end faces of the metal frame, it is easy to increase the joint strength even during welding and brazing, and as a result, it contributes to reducing the thickness of the frame.

In the thermoelectric conversion device 31 of FIG. 9 , the structure of the heat-absorbing electrode is also different. Metal protrusions 34 are vertically provided on the main surface of the cover 32 that faces the inside of the thermoelectric conversion device so as to surround the region where the end faces of the thermoelectric elements 10 and 11 face the heat-absorbing side. The metal protrusion 34 is preferably formed of a good conductor such as Cu. A fine metal wire mesh 6 is disposed on the region surrounded by the metal protrusions, and end faces of the thermoelectric elements 10 and 11 on the heat-absorbing side are disposed so as to be crimped on the fine metal wire mesh 6 . In this way, metal protrusions 34 suppress misalignment between metal fine wire mesh 6 and thermoelectric elements 10 and 11, thereby reducing contact failure.

FIG. 10 shows a fifth embodiment of a thermoelectric conversion device according to the present invention. In this thermoelectric conversion device 41 , an insulating member ceramic plate 42 is vertically provided in the inner space of a box-shaped structure. Ceramic plate 42 is disposed between capacitive elements 10 , 11 electrically connected to heat-dissipating-side electrodes 13 of thermoelectric elements 10 , 11 . The height of the ceramic plate is set to reach the heat-absorbing side electrode 5 and not reach the height of the cover and the heat-absorbing side insulating substrate.

FIG. 11 shows a sixth embodiment of a thermoelectric conversion device according to the present invention. This thermoelectric conversion device 51 uses a plurality of glass bulbs 52 having a particle size distribution of 0.18 mm to 0.22 mm as an insulating member instead of the ceramic plate 42 . Glass spheres fill the inner space of the box-shaped structure. It is preferable to exclude as much as possible the gap between the glass bulbs and set it as a reduced-pressure atmosphere. By using the glass bulbs 52, it is possible to omit the step of arranging insulating members separately, and the manufacturability becomes easy.

FIG. 12 shows a seventh embodiment of the thermoelectric conversion device according to the present invention. The thermoelectric conversion device 61 of the present embodiment is configured such that the distance between the thermoelectric elements surrounded by the heat-absorbing electrode 5 is greater than the distance between the thermoelectric element and the thermoelectric element surrounded by the heat-absorbing electrode adjacent to the heat-absorbing electrode 5 . interval is short. Specifically, the distance between the p-type thermoelectric element 10b and the n-type thermoelectric element 11b electrically connected by the heat-absorbing electrode 5 is greater than that between the p-type thermoelectric element 10b and the n-type thermoelectric element 11a electrically connected by the heat-releasing electrode 13. interval is short. With this configuration, the mounting density of the thermoelectric elements is increased while ensuring insulation between adjacent heat-absorbing-side electrodes 5 , and the power generation performance per unit area is improved. As the material of the frame 9, in order to reduce the heat flow to the frame 9 and increase the heat flow to each thermoelectric element, the thermal conductivity should preferably be small. Here, in order to facilitate welding with the cover 2, Kovar, which is the same material as the cover 2, is used. As shown in FIG. 12 , the joint surface of the frame 9 and the solder 8 has a triangular chamfered cross section, and the solder 8 is rounded to correspond to the chamfered shape to improve the joint strength. The reason for making the frame 9 and the solder 8 such a shape when increasing the bonding strength is that, assuming that the frame 9 and the solder 8 become thicker in the horizontal direction of the figure, only the heat in this part becomes easy to conduct. , In addition, it also becomes a cause of an increase in the size of the device itself. In addition, the material of the solder 8 is not particularly limited as long as the bonding property does not decrease at the operating temperature of the thermoelectric conversion device.

In addition, the frame 9 is provided with a folded portion that is folded outward at the contact portion with the cover 2, and by enlarging the area of the contact surface of the frame 9 with the cover 2, the frame 9 and the cover 2 can be easily welded. In addition, by welding the folded portion of the frame 9 and the end portion of the cover 2 from the outside with a laser, it is easy to carry out an appearance inspection about the welding state, thus ensuring airtightness. In addition, the frame 9 can be manufactured by cutting by machining, but the processing method is not particularly limited as long as it can be processed into the same shape as above.

In addition, by providing the cover 2 with a bent portion that bends in a direction that applies pressure to the inside of the joint portion with the frame 9, the cover 2 has elasticity, and the cover 2 can be pressed against the heat-absorbing side substrate 4. , while easily performing assembly with the frame 9 when welding.

The operating temperature of the exothermic side was set at 200° C., copper was used for the electrodes, a ceramic substrate of Si ₃ N ₄ base material was used for the exothermic side substrate 14 , and Pb-8Sn-2Ag solder paste was used as the solder material. In addition, the material of solder is not particularly limited as long as its melting point is 200° C. or higher.

The external wiring 18 taken out from the thermoelectric conversion device through the through hole 16 is coated with an insulating resin 19 . By using the through hole 16 for drawing out the wiring, it is easy to ensure the airtightness of the thermoelectric conversion device. In addition, by overlapping the metal foil 15 with the respective outer surfaces of the insulating resin 19 , contact thermal resistance at the time of contact with a heat source such as a heat sink can be reduced.

As described above, in the thermoelectric conversion device according to the present embodiment, the heat-absorbing-side electrode set to be mounted on the heat-absorbing surfaces of a plurality of p-type thermoelectric elements and n-type thermoelectric elements is slidably pressed against the cover. The holding structure prevents damage to the junction and the thermoelectric element even if the cover and the thermoelectric element thermally expand at different rates, thereby providing a thermoelectric conversion device with superior reliability compared with conventional thermoelectric conversion devices.

In addition, by using thin metal wires having a mesh structure for the heat-absorbing side electrodes, variations in element height during assembly of the converter can be absorbed, thereby providing a highly reliable thermoelectric converter with improved bondability.

In addition, since the thermoelectric conversion device has a sealed structure, it is possible to prevent deterioration due to oxidation of the thermoelectric element and the junction, and it is possible to provide a highly reliable thermoelectric conversion device.

By sandwiching the heat-absorbing-side insulating substrate 4, the heat-absorbing-side electrode 5, and the metal fine-wire mesh 6 between the cover 2 and the heat-releasing-side substrate 14, even if the conversion device is heated and deformed after heating, it is possible to prevent thermal deformation between the thermoelectric elements 10, 11 and the thermoelectric elements 10 and 11. Sliding occurs on the contact surface of the heat-absorbing-side electrode 5 , resulting in damage to the element or the like.

By providing a convex portion on the periphery of the heat-absorbing electrode 5 , the convex portion contacts the side surface of the thermoelectric element during assembly or thermal deformation, thereby preventing detachment from the heat-absorbing-side end surface of the thermoelectric element.

The metal fine wire mesh 6 can absorb the height variation of the thermoelectric element by the deformation of the mesh structure and the assembly variation when the thermoelectric element is bonded to the heat-releasing side substrate by the solder 12, so that pressure can be applied to the entire thermoelectric element. In addition, by combining the heat-absorbing electrode 5 and the fine metal wire mesh 6 provided with protrusions on the periphery, it is possible to prevent the metal fine wire mesh 6 from coming off, and the assemblability is also improved. The heat-absorbing-side electrode 5 may also be formed with a mesh structure.

The heat-absorbing side electrodes 5 need to be electrically independent, but to achieve a sealed structure, the cover 2 and the frame 9 need to be welded, and the cover 2 is preferably made of metal from the viewpoint of operability. Therefore, insulation can be ensured by providing the heat-absorbing-side insulating substrate 4 between the cover 2 and the heat-absorbing-side electrode 5 . In addition, by arranging the ceramic plate 42 between the thermoelectric elements 10 and 11, the insulation between the thermoelectric elements 10 and 11 can be improved. Here, by providing metal foils on both surfaces of the heat-absorbing-side insulating substrate, heat paths from the cover 2 to the thermoelectric elements 10 and 11 can be formed, and variations in the thickness direction during assembly of the absorption conversion device can be expected. . In addition, by forming an insulating thin film on the contact surface of the cover 2 with the heat-absorbing side electrode 5 and the contact surface of the heat-absorbing-side electrode 5 with the cover 2, the heat-absorbing side insulating substrate 4 can be omitted, the structure is simple, and the thermal On the one hand, the temperature difference between the heat-absorbing object and the heat-absorbing end surface of the thermoelectric element can be reduced, and the power generation efficiency as a thermoelectric conversion device can be improved.

By arranging an insulating member that limits the position of the thermoelectric elements between adjacent thermoelectric elements, even if a large deviation is applied to the thermoelectric elements due to unexpected protrusion, it is possible to prevent contact with the adjacent thermoelectric elements, and it is possible to prevent Detachment of the electrode from the endothermic side of the slide. The insulating member may be a liquid or a solid, but when the internal space is filled with a substance, due to thermal expansion of the substance, damage to the welded part and poor conduction may occur. The structure of a powder or a plurality of particulate matter. It is preferable that the powder and particulate matter have a structure that does not fuse with each other in the operating temperature range of the thermoelectric conversion device. In addition, in the case of a wall structure, it is preferable to be configured to be joined to only one of the members constituting the tank structure or to one continuous plane of the tank structure in which a plurality of planes are discontinuously connected.

In this thermoelectric conversion device, the operating temperature on the high-temperature side is set to 600° C., and therefore, p-type and n-type thermoelectric elements having a scuteldite structure are used as thermoelectric elements. In the air atmosphere of 600°C, the SKUTTERDIT thermoelectric element is oxidized, and the performance decreases. Therefore, by adopting a sealed structure composed of cover 2, frame 9, and heat radiation-side substrate 14, a reduced-pressure atmosphere can be realized, oxidation of each thermoelectric element 10, 11 can be prevented, and thermoelectric conversion device 1 can be installed in any place.

By making the distance between the thermoelectric elements surrounded by the heat-absorbing electrode 5 shorter than the distance between the thermoelectric element and the thermoelectric element surrounded by the heat-absorbing electrode adjacent to the heat-absorbing electrode 5, the adjacent heat-absorbing electrodes can be secured. 5 The insulation between each other can increase the installation density of thermoelectric elements and improve the power generation performance per unit area.

By setting the joint surface of the frame 9 with the solder 8 into a chamfered shape, the joint strength between the frame 9 and the solder 8 can be improved.

By providing an outwardly folded folded portion on the contact portion of the frame 9 with the cover 2, the area of the contact surface between the frame 9 and the cover 2 is enlarged, so that the welding of the frame 9 and the cover 2 can be facilitated.

By welding the frame 9 and the folded portion and the end of the cover 2 from the outside with a laser, an appearance inspection about the welding state is easily performed, thereby ensuring airtightness.

By providing the bent portion, the cover 2 has elasticity by bending in the direction of applying pressure to the inside of the joint portion of the cover 2 with the frame 9, so that the cover 2 can be easily pressed against the heat-absorbing side substrate 4. Assembly when welding frame 9.

Furthermore, the deformable structural part is a part whose contact area with the thermoelectric element increases after the surface is deformed when pressure is applied to the surface by the thermoelectric element. Shapes, plate-shaped parts formed by molding, etc.

Claims (29)

1. A thermoelectric conversion device, characterized in that it has: Wiring substrate; a plurality of thermoelectric elements, one end surface of which is bonded to the wiring substrate; a plurality of electrode parts configured to move in contact with the other end faces of the plurality of thermoelectric elements; A cover portion and a bonding member holding the plurality of thermoelectric elements and the plurality of electrode members, the cover portion being configured to apply pressure to the hot spot element. 2. The thermoelectric conversion device according to claim 1, wherein the electrode member has a convex portion defining a position of the thermoelectric element, and the convex portion is provided so as to surround a region where the thermoelectric element is crimped. 3. The thermoelectric conversion device according to claim 1, wherein the electrode member is arranged to be electrically connected in series with the thermoelectric element. 4. The thermoelectric conversion device according to claim 1, wherein the electrode member includes an outer member and a deformable structural member made of a conductive material provided between the thermoelectric element and the outer member. 5. The thermoelectric conversion device according to claim 1, wherein insulating members defining the positions of the thermoelectric elements are disposed between the thermoelectric elements, respectively. 6. The thermoelectric conversion device according to claim 1, wherein the space between the thermoelectric elements surrounded by the electrode parts is larger than that between the thermoelectric elements and another thermoelectric element surrounded by another electrode part adjacent to the electrode parts. The spacing between elements is short. 7. The thermoelectric conversion device according to claim 1, wherein the bonding member is a bonding member that is bonded to the wiring board with solder, and the bonding surface of the bonding member with the solder is formed into a chamfered shape. . 8. The thermoelectric conversion device according to claim 1, wherein a bend that is folded outward is provided at a portion of the coupling member that is in contact with the cover. 9. The thermoelectric conversion device according to claim 1, wherein a bent portion bent in a direction of pressure is provided on the cover portion. 10. A thermoelectric conversion device, comprising: Wiring substrate; multiple thermoelectric elements; a plurality of fixed junctions connecting one end surface of the plurality of thermoelectric elements to the wiring substrate; a plurality of movable junctions connecting the other end faces of the plurality of thermoelectric elements with the plurality of electrode parts; A pressure housing holds the plurality of thermoelectric elements and the plurality of electrode assemblies. 11. The thermoelectric conversion device according to claim 10, wherein the fixed joint includes a solder joint, and the movable joint does not include a solder joint. 12. A method of manufacturing a thermoelectric conversion device, comprising: bonding one end face of the plurality of thermoelectric elements to the wiring substrate; disposing a plurality of electrode parts in sliding contact with the other end surfaces of the plurality of thermoelectric elements; disposing a cover on the outside of the electrode part; and The cover is bonded to the wiring substrate by the bonding member, thereby applying pressure between the cover and the wiring substrate. 13. The method for manufacturing a thermoelectric conversion device as claimed in claim 12, further comprising: A deformable structural part made of electrically conductive material is arranged between the thermoelectric element and the electrode part. 14. The method for manufacturing a thermoelectric conversion device as claimed in claim 12, further comprising: An insulating member defining the position of the thermoelectric elements is arranged between the thermoelectric elements. 15. The method of manufacturing a thermoelectric conversion device as claimed in claim 12, characterized in that: Ceramics are used for the wiring substrate, Kovar is used for the cover portion, and ceramics are used for the bonding member, and the manufacturing method further includes: bonding the bonding member and the wiring substrate by solder; and The joining member and the cover are bonded by brazing filler metal and Kovar. 16. The method for manufacturing a thermoelectric conversion device as claimed in claim 12, further comprising: forming the bonding surface of the bonding member and the wiring substrate into a chamfered shape; and The bonding surface of the bonding member is bonded to the wiring substrate by solder. 17. The method for manufacturing a thermoelectric conversion device as claimed in claim 12, further comprising: The thermoelectric elements are arranged on the wiring substrate such that the interval between the thermoelectric elements surrounded by the above-mentioned electrode member is larger than that between the thermoelectric element and another thermoelectric element surrounded by another electrode member adjacent to the electrode member. Short intervals. 18. The method for manufacturing a thermoelectric conversion device as claimed in claim 12, further comprising: opening a sealing hole for the cover; placing a thermoelectric device in which the cover and the wiring substrate are bonded by a bonding member in a decompression atmosphere; and The sealed hole is closed under the reduced pressure atmosphere. 19. The method for manufacturing a thermoelectric conversion device according to claim 18, wherein the sealing hole is closed by laser. 20. The method for manufacturing a thermoelectric conversion device according to claim 12, further comprising: Through-holes are formed through the wiring substrate to pass the wires, thereby taking out the electromotive force generated in the thermoelectric elements. 21. A thermoelectric conversion device, comprising: Wiring substrates made of ceramics; a plurality of thermoelectric elements, one end surface of which is bonded to the wiring substrate; a plurality of electrode parts configured to be in sliding contact with the other end faces of the plurality of thermoelectric elements; a cover portion made of Kovar disposed on the outside of said electrode part; and The bonding member is bonded to the wiring substrate through the solder, and bonded to the lid through the brazing filler metal and Kovar, thereby exerting pressure between the lid and the wiring substrate. 22. A thermoelectric conversion device, comprising: Wiring substrate; a plurality of thermoelectric elements, one end surface of which is bonded to the wiring substrate; a plurality of electrode parts configured to be in sliding contact with the other end faces of the plurality of thermoelectric elements; a cover portion disposed on the outside of the electrode part; a bonding member that bonds the wiring substrate to the cover, thereby applying pressure between the cover and the wiring substrate; and The sealed hole, placed on the lid, is closed in a reduced pressure atmosphere. 23. A thermoelectric conversion device, comprising: Wiring substrate; a plurality of thermoelectric elements, one end surface of which is bonded to the wiring substrate; a plurality of electrode parts configured to be in sliding contact with the other end faces of the plurality of thermoelectric elements; a cover portion disposed on the outside of the electrode part; a bonding member that bonds the wiring substrate to the cover, thereby applying pressure between the cover and the wiring substrate; and The electrical vias are arranged on the wiring substrate, through which the wires are passed through the wiring substrate, so as to take out the electromotive force generated in the thermoelectric element. 24. The thermoelectric conversion device according to any one of claims 21-23, wherein the electrode member has a convex portion defining the position of the thermoelectric element, and the convex portion is arranged so as to surround the thermoelectric element and be crimped. Area. 25. The thermoelectric conversion device according to any one of claims 21-23, characterized in that, the electrode part comprises an outer part and a conductive material disposed between the thermoelectric element and the outer part. Deformed structural components. 26. The thermoelectric conversion device according to any one of claims 21 to 23, wherein insulating members defining the positions of the thermoelectric elements are arranged between the thermoelectric elements, respectively. 27. The thermoelectric conversion device according to claim 24, wherein the distance between the thermoelectric elements surrounded by the electrode parts is larger than that between the thermoelectric elements and another thermoelectric element surrounded by another electrode part adjacent to the electrode part. The spacing between elements is short. 28. The thermoelectric conversion device according to any one of claims 21-23, wherein the bonding member is a bonding member that is bonded to the wiring board with solder, and the bonding of the bonding member to the solder is The face is formed into a chamfered shape. 29. The thermoelectric conversion device according to any one of claims 21 to 23, wherein a bent portion bent in a direction of pressure is provided on the cover portion.

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