JP6149754B2 - Thermoelectric generator - Google Patents

Description

  The present invention relates to a thermoelectric power generator, and more particularly to a thermoelectric power generator that performs thermoelectric power generation using a temperature difference between both heat media while passing a high temperature heat medium and a low temperature heat medium.

  As a conventional thermoelectric generator that arranges a plurality of thermoelectric elements between a high-temperature heat source and a low-temperature heat source, the exhaust heat recovery type thermoelectric that recovers the exhaust heat of the exhaust gas of the internal combustion engine while converting it into electrical energy A power generation device is known.

  As such a thermoelectric power generation device, for example, a cylindrical thermoelectric power generation unit containing a plurality of modular thermoelectric elements is arranged vertically in one passage through which exhaust gas or cooling water passes, and the inside of each thermoelectric power generation unit The other passage through which the cooling water or the exhaust gas passes is formed, and thermoelectric power generation is performed using the temperature difference between the inside and outside of the plurality of cylindrical thermoelectric power generation units arranged in parallel (see, for example, Patent Document 1).

  A thermoelectric power generation system is also known in which fins are attached to a cylindrical thermoelectric power generation unit containing a plurality of thermoelectric elements each modularized to form a cartridge, and a plurality of thermoelectric power generation units arranged in parallel are arranged in parallel (for example, , See Patent Document 2).

  In addition to providing an insulating member between a heater element having a PTC (Positive Temperature Coefficient) heater and a case supporting the heater element, an elastic member is interposed between the insulating member and the case, thereby providing a heater. A device that absorbs thermal expansion of an element to prevent deformation of the heater element is known (for example, see Patent Document 3).

Special table 2012-533972 gazette US Patent Application Publication No. 2013/0186448 JP 2009-257114 A

  However, in the conventional thermoelectric power generation apparatus as described above, for example, when the case supporting the thermoelectric power generation unit formed as a cartridge forms the exhaust gas passage, the thermal expansion amount of the exhaust gas passage formation portion of the case is small. Thermoelectric power generation units that allow cooling water to pass through inside, especially pipes that form cooling water passages on the inner periphery thereof (hereinafter referred to as cooling water piping) are reduced in thermal expansion. Thermal stress and thermal strain were likely to occur in the fixed part of the case.

  That is, in the thermoelectric power generation unit and the case, the member on the exhaust gas passage side has a large amount of thermal expansion, whereas the member on the cooling water passage side has a small amount of thermal expansion. It was easy to occur.

  For this reason, there is a concern that the power generation performance of the thermoelectric generator may be reduced when, for example, the stress or strain from the coupling portion is easily transmitted to the thermoelectric generator in the thermoelectric generator unit due to downsizing of the thermoelectric generator or the like. .

  On the other hand, a thermal stress can be relieved by providing a bellows (bellows) at the end of the thermoelectric power generation unit formed into a cartridge (see paragraph 0214 of FIG. 30 and FIG. 30B). However, if the bellows portions are provided in the two high temperature side and low temperature side cylindrical bodies arranged inside and outside the modular thermoelectric element group, the thermoelectric power generator can be reduced in size from both the structural and assembly aspects. There is a drawback that it is difficult to meet the demand for higher efficiency.

  Therefore, the present invention effectively suppresses the generation of large stress and strain between the high temperature heat medium side member and the low temperature heat medium side member without incurring the complexity of the structure and the assembly. An object of the present invention is to provide a thermoelectric generator that can meet demands for miniaturization and high efficiency with improved efficiency and heat recovery efficiency.

In order to achieve the above object, the thermoelectric generator according to the present invention includes a case having one heat medium passage through which a high-temperature side heat medium passes and a heat medium passage through which the low-temperature side heat medium passes through each inner circumferential side. A plurality of cylindrical thermoelectric generator units to be formed, and the thermoelectric generator units are supported by the case so as to be substantially orthogonal to the flow direction of the heat medium on the high temperature side in the one heat medium passage. A thermoelectric generator, wherein each of the thermoelectric generator units includes an inner cylindrical heat transfer member that forms the other heat medium passage, and an outer cylindrical heat transfer member that surrounds the inner cylindrical heat transfer member. A thermoelectric module having a plurality of thermoelectric elements interposed between the inner cylindrical heat transfer member and the outer cylindrical heat transfer member . The inner cylindrical heat transfer member On at least one side of the member of the pre said casing, together with the flexible portion to absorb expansion by elastic deformation of said inner cylindrical heat transfer member with respect to the casing is provided, in the case, each of the thermoelectric power generation unit A plurality of sliding support portions for slidably supporting at least one end of the outer cylindrical heat transfer member in the axial direction are provided , and the case includes the respective inner cylindrical heat transfer members. an outer plate portion which is airtightly coupled with the outer side of the thermoelectric power generation unit from the sliding support portion of the heat transfer member, a cylindrical heat transfer of the outside of the respective through the plurality of sliding support portions And a terminal chamber that communicates with the sliding gaps of the plurality of sliding portions is formed between the outer plate portion and the inner plate portion .

  With this configuration, in the present invention, expansion and contraction of the inner cylindrical heat transfer member with respect to the case is absorbed by the flexible portion provided on at least one of the inner cylindrical heat transfer member and the case, At least one end portion of the outer cylindrical heat transfer member is slidably supported by the sliding support portion of the case, so that the outer cylindrical heat transfer member can be expanded and contracted and axially displaced with respect to the case. The The inner cylindrical heat transfer member and the case are hermetically coupled to the outer side of the thermoelectric power generation unit from the sliding support portion of the case, thereby preventing the heat medium on the high temperature side from leaking out of the case. The Therefore, it is possible to relieve thermal stress and seal the fixed part of the thermoelectric power generation unit without providing a double tube structure coupling part at the end of the thermoelectric power generation unit that is made into a cartridge. Thermal stress and thermal strain generated between the member on the high temperature heat medium side and the member on the low temperature heat medium side can be suppressed without complicating or increasing the size. As a result, it becomes a thermoelectric power generation apparatus that can meet the demands for miniaturization and high efficiency with improved power generation efficiency and heat recovery efficiency.

  According to the present invention, without significantly complicating the structure and assembly, it is possible to effectively suppress the occurrence of large stress and strain between the member on the high temperature heat medium side and the member on the low temperature heat medium side, It is possible to provide a thermoelectric generator that can meet the demands for miniaturization and high efficiency with improved power generation efficiency and heat recovery efficiency.

1 is a schematic configuration diagram of a thermoelectric generator according to a first embodiment of the present invention. FIG. 2A is a longitudinal sectional view of a cylindrical thermoelectric power generation unit formed as a cartridge of the thermoelectric power generation device according to the first embodiment of the present invention, and FIG. 2B is related to the first embodiment of the present invention. It is a cross-sectional view of the cylindrical thermoelectric power generation unit formed into a cartridge of the thermoelectric power generation device. 1 is a schematic plan view including a cross section of a main part of a thermoelectric power generator according to a first embodiment of the present invention. It is a schematic block diagram of the thermoelectric power generating apparatus which concerns on 2nd Embodiment of this invention. It is a schematic block diagram of the thermoelectric power generating apparatus which concerns on 3rd Embodiment of this invention.

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

(First embodiment)
1 to 3 show a schematic configuration of the thermoelectric generator according to the first embodiment of the present invention.

  Note that the thermoelectric generator of the present embodiment uses the exhaust gas of the internal combustion engine as the high temperature side heat medium, and the cooling medium such as the cooling water of the internal combustion engine as the low temperature side heat medium (not limited to water, the low temperature side heat medium). A suitable coolant) is used as a medium. This thermoelectric power generation apparatus is configured to exhaust heat of exhaust gas of an internal combustion engine by thermoelectrically generating a plurality of thermoelectric elements between a high-temperature heat source and a low-temperature heat source in a thermal parallel manner and electrically exclusively in series. It has a waste heat recovery function that recovers while converting to electrical energy.

  First, the configuration of the thermoelectric power generator according to this embodiment will be described.

  As shown in FIG. 1, the thermoelectric power generation apparatus 10 of the present embodiment includes, for example, a case 11 in which a pair of concave case members are abutted and welded. In the case 11, a gaseous high-temperature heat medium is provided. An exhaust gas passage 12 is formed as one heat medium passage through which the gas passes.

  The case 11 constitutes a part of an exhaust pipe P through which exhaust gas from the engine passes, for example, and the exhaust gas passage 12 has exhaust gas discharged from a vehicle driving engine (internal combustion engine) (not shown). G flows in.

  Inside the case 11, a plurality of substantially cylindrical thermoelectric power generation units 13 that intersect substantially at right angles to the axial direction of the exhaust gas passage 12 are arranged in parallel and at equal intervals in parallel. A cooling water passage 31 (the other heat medium passage) through which engine cooling water W (cooling medium), which is a liquid low-temperature heat medium, passes, is formed inside these thermoelectric power generation units 13.

  The cooling water passages 31 of the plurality of thermoelectric power generation units 13 are connected in series from the upstream side to the downstream side of the exhaust gas passage 12, and the cooling water close to the upstream end side of the exhaust gas passage 12 in the case 11 as a whole. A cooling water passage 30 having a cooling water outlet 30b close to the inlet 30a and the downstream end side of the exhaust gas passage 12 is formed. The cooling water passage 30 may be configured to branch in parallel in the case 11.

  As shown in FIG. 2A and FIG. 2B, each thermoelectric power generation unit 13 includes an inner cylindrical heat transfer member 32, an outer cylindrical heat transfer member 33, and an inner cylindrical heat transfer member. 32 and a thermoelectric element module 35 having a plurality of thermoelectric elements 34 a and 34 b interposed between the outer cylindrical heat transfer member 33.

  The inner cylindrical heat transfer member 32 has an inner peripheral wall surface 32a that forms a cooling water passage 31 through which the cooling water W passes, and a substantially cylindrical pipe in which the cooling water passage 31 extends in the axial direction. It has become. Further, a plurality of inner cylindrical heat transfer members 32 arranged in parallel in the case 11 so as to form the cooling water passage 30 are provided with cooling water pipes 51 on one end side of the plurality of thermoelectric generation units 13 and the plurality of thermoelectric generation units 13. Are connected in series with the cooling water pipe 52 on the other end side, and the cooling water pipes 53 and 54 on the cooling water introduction side and the cooling water discharge side are connected to both ends thereof.

  The outer cylindrical heat transfer member 33 has an inner peripheral surface 33 a having a diameter larger than the outer diameter of the inner cylindrical heat transfer member 32 and an outer peripheral wall surface 33 b that contacts the exhaust gas G in the exhaust gas passage 12. ing.

  The outer cylindrical heat transfer member 33 surrounds the inner cylindrical heat transfer member 32 from the outer peripheral side and is spaced from the outer peripheral surface 32b of the inner cylindrical heat transfer member 32 by a predetermined radial distance. The inner cylindrical heat transfer member 32 is arranged coaxially (on the same central axis).

  The plurality of thermoelectric elements 34a and 34b are configured by, for example, a plurality of pairs of N-type and P-type thermoelectric conversion elements that generate an electromotive force according to a temperature difference by the Seebeck effect, and the N-type thermoelectric elements 34a and P-type The thermoelectric element 34b is electrically connected in series in the circumferential direction via the inner electrode 36a and the outer electrode 36b, so that the thermoelectric element module 35 is configured.

  Further, the plurality of thermoelectric elements 34a and 34b are rod-shaped elements arranged in parallel at equal angular intervals in the circumferential direction of the inner cylindrical heat transfer member 32 and the outer cylindrical heat transfer member 33, and the lengths of the respective elements. Is a length close to the diameter of the exhaust gas passage 12.

  In the present embodiment, each thermoelectric power generation unit 13 constitutes a thermoelectric element module 35 in which a plurality of rod-shaped thermoelectric elements 34a and 34b are arranged in parallel at equal angular intervals. A plurality of pairs of N-type and P-type thermoelectric elements arranged alternately in the axial direction may be used. Further, it goes without saying that the plurality of rod-like or plate-like thermoelectric elements 34a, 34b can be divided into a plurality of parts in the axial direction and the arrangement of these divided bodies can be shifted in the circumferential direction. Further, here, each of the pair of thermoelectric elements 34a and 34b having a so-called π-type structure together with either the inner electrode 36a or the outer electrode 36b is thermally connected in parallel and electrically in series. The present invention can be applied to other than the π-type structure.

  The inner cylindrical heat transfer member 32 has an electrical insulation property that electrically insulates the plurality of inner electrodes 36a from each other at least on the outer peripheral surface portion on the center side (other than both ends) in contact with the plurality of inner electrodes 36a. doing.

  In addition, the outer cylindrical heat transfer member 33 has an electrical insulation property that electrically insulates the plurality of outer electrodes 36b from each other at least in an inner peripheral portion in contact with the plurality of outer electrodes 36b.

  Furthermore, as shown in FIG. 2A, a cylindrical space S between the inner cylindrical heat transfer member 32 and the outer cylindrical heat transfer member 33, which is an arrangement space of each thermoelectric element module 35, is a pair. Are closed by an annular closing member 37a, 37b, and an inert gas, for example, is enclosed as an oxidation deterioration preventing agent for the thermoelectric element module 35 therein.

  By the way, the plurality of thermoelectric power generation units 13 are connected to each other by electrical wiring such as an element lead wire 38 so as to electrically connect the internal thermoelectric element modules 35 to each other and to a battery charging circuit (not shown). ing. Thereby, the some thermoelectric generation unit 13 can store the electrical energy collect | recovered from the exhaust heat which exhaust gas has in a battery.

  The element lead wires 38 are substantially U-shaped or arched between the thermoelectric element modules 35 of each pair of adjacent thermoelectric power generation units 13 so as to follow the elongation in the longitudinal direction of the case 11 (the axial direction of the exhaust gas passage 12). The surplus length that can follow the elongation in the longitudinal direction of the case 11 is set.

  Further, the plurality of thermoelectric power generation units 13 have a plurality of fins 41 on the respective outer peripheral sides. Each of the plurality of fins 41 is an annular plate that protrudes radially outward from the outer cylindrical heat transfer member 33 at a certain height, and on the outer peripheral side of each thermoelectric power generation unit 13, It arrange | positions so that it may mutually space apart at a fixed interval in an axial direction.

  Further, these fins 41 absorb the exhaust heat of the exhaust gas by the heat transfer from the exhaust gas flowing in the exhaust gas passage 12, and are efficient for the outer cylindrical heat transfer member 33 that is the heat receiving material on the high temperature side. It is an endothermic fin that conducts heat well. The protrusion height of each thermoelectric power generation unit 13 to the outside of the radiation is constant throughout the entire axial direction and circumferential direction as shown in FIG. 2B, for example, but the protrusion height is partially different. Alternatively, the fins 41 may be extended throughout the case 11 so that the plurality of thermoelectric generation units 13 are coupled to the same fin 41.

  On the other hand, at least one of the inner cylindrical heat transfer member 32 and the case 11 has a relative position of the inner cylindrical heat transfer member 32 with respect to the case 11, for example, on the inner cylindrical heat transfer member 32 side. A flexible portion 55 is provided that absorbs elastic expansion and contraction by elastic deformation.

  This flexible part 55 is arrange | positioned at the both ends of the inner cylindrical heat-transfer member 32, for example, and has comprised the bellows shape, respectively.

  In FIG. 2A, the cooling water pipes 51 and 52 each having a flexible portion 55 are coupled to both end sides of the inner cylindrical heat transfer member 32 so that the inner cylindrical heat transfer in the case 11. A pair of flexible portions 55 located on both ends of the member 32 are configured. However, the pair of flexible portions 55 may be integrally formed at both end portions of the inner cylindrical heat transfer member 32. Further, the cross section of the wall surface of the flexible portion 55 may be U-shaped or arched instead of corrugated.

  Further, the flexible portion 55 only needs to be able to absorb expansion and contraction due to thermal deformation or the like of the inner cylindrical heat transfer member 32 by elastic deformation. Therefore, the first side plate located on the left and right ends of the case 11 shown in FIG. At least one of the portions 11a and 11b has an annular flexible portion 11f (illustrated by a dotted line in FIG. 2A) that absorbs expansion / contraction due to thermal deformation or the like of the inner cylindrical heat transfer member 32 with respect to the case 11 by elastic deformation. ) May be provided. Alternatively, at least one end side of the inner cylindrical heat transfer member 32 may be provided with a flange-shaped annular flexible plate portion fixed to the case 11 on the outer peripheral side.

  At least one end portion of the outer cylindrical heat transfer member 33, for example, outer peripheral surface portions 33f and 33g (both end portions) on both end sides of the outer cylindrical heat transfer member 33 are the second side plate portion 11c of the case 11, respectively. 11d (sliding support portion) is supported so as to be slidable in the axial direction.

  Specifically, as shown in FIG. 2A and FIG. 3, between the outer peripheral surface portions 33f and 33g on the both ends of the outer cylindrical heat transfer member 33 and the case 11, elasticity at high temperatures and A heat-resistant elastic ring 56 made of a heat-resistant material having a slight air permeability is interposed, and the heat-resistant elastic ring 56 is supported by the second side plate portions 11c and 11d of the case 11 via an annular mounting plate 11s. Yes. These heat-resistant elastic rings 56 become sliding support portions provided on the second side plate portions 11c and 11d so as to support (slide support) both ends of the outer cylindrical heat transfer member 33 so as to be slidable in the axial direction. ing.

  More specifically, the heat-resistant elastic ring 56 is made of, for example, a metal mesh made of a thin stainless steel wire knitted in a cylindrical shape, and is expanded or contracted by thermal deformation of the outer cylindrical heat transfer member 33 or the case 11. It has flexibility or elasticity that can absorb diameter and radial displacement. Further, the heat-resistant elastic ring 56 has heat resistance that can withstand exhaust heat, corrosion resistance to condensed water containing exhaust components, filter characteristics against dust and the like, and some air permeability.

  Thereby, the outer peripheral surface parts 33f and 33g of the both ends of the outer cylindrical heat transfer member 33 are in a certain range that is equal to or more than the degree of thermal deformation with respect to the second side plate parts 11c and 11d of the case 11 via the pair of heat-resistant elastic rings 56. It is supported so that axial displacement (sliding) and expansion / contraction and radial displacement are possible.

  Further, the inner cylindrical heat transfer member 32 and the case 11 are fixed to each other on the outer side of the thermoelectric generation unit 13 from the outer peripheral surface portions 33f and 33g on both ends of the outer cylindrical heat transfer member 33, for example, by arc welding. Are tightly coupled with each other.

  A pair of terminal chambers 57 and 58 are formed between the first side plate portions 11 a and 11 b and the second side plate portions 11 c and 11 d of the case 11 so as to be shielded from the outside air near the outer periphery of the case 11. . Although the pair of terminal chambers 57 and 58 are generally cut off from the exhaust gas passage 12 by the second side plate portions 11c and 11d and the heat-resistant elastic ring 56, the case 11 and the outside of the case 11 and the outside of the pair of terminal chambers 57 and 58 can be breathed due to temperature changes. Leakage (gas leak) from the exhaust gas passage 12 can occur in the sliding gap portion with the cylindrical heat transfer member 33.

  An arrow Fr in FIG. 1 indicates the front direction of the vehicle, an arrow Rh in FIG. 1 indicates the right direction of the vehicle, and indicates an approximate installation direction of the thin flat thermoelectric generator 10 in the vertical direction. Yes.

  Next, the operation will be described.

  In the thermoelectric power generation apparatus 10 of the present embodiment configured as described above, a high-temperature exhaust gas that is a high-temperature side heat medium passes through the exhaust gas passage 12 during operation of the internal combustion engine, and a plurality of thermoelectric generators. The cooling water of the internal combustion engine, which is a low-temperature heat medium, passes through the cooling water passage 30 passing through the power generation unit 13.

  In this state, the case 11 expands due to heat from the high-temperature exhaust gas, while the thermal expansion of the plurality of thermoelectric power generation units 13 through which the cooling water passes, particularly the thermal expansion of the cylindrical heat transfer member 32 inside thereof is suppressed. A contraction state occurs in which the inner cylindrical heat transfer member 32 is relatively short with respect to the case 11. Therefore, if a plurality of thermoelectric power generation units 13 are simply fixed to the case 11, thermal stress and thermal strain can concentrate on the fixed portion.

  In the present embodiment, the inner cylinder with respect to the case 11 is provided by the flexible portion 55 (or / and the annular flexible portion 11f) provided on at least one member of the inner cylindrical heat transfer member 32 and the case 11. The relative contraction of the heat transfer member 32 is absorbed by the bending of the flexible portion 55. Therefore, it becomes difficult for thermal stress and thermal strain to concentrate on the fixed portion of the plurality of thermoelectric power generation units 13 with respect to the case 11.

  Further, the outer cylindrical heat transfer member 33 is slidably supported by the case 11 via the heat-resistant elastic rings 56 at both ends, so that the outer cylindrical heat transfer member 33 extends and contracts with respect to the case 11 and in the axial direction. Displacement, expansion / contraction diameter and radial displacement associated with thermal deformation are allowed.

  Then, the inner cylindrical heat transfer member 32 and the outer cylindrical heat transfer member 33 on the outer side of the thermoelectric generator unit 13 than the heat-resistant elastic ring 56 of the case 11 that supports the outer peripheral surface portions 33f and 33g on both ends of the outer cylindrical heat transfer member 33 and Since the case 11 is hermetically coupled, leakage of exhaust gas (a gaseous high-temperature heat medium) to the outside of the case 11 is prevented.

  Therefore, the thermal stress and thermal strain can be alleviated and sealed at the joints without providing a joint part of the double tube structure to join the case 11 at the end parts of the plurality of thermoelectric generator units 13 formed into cartridges. Etc. are possible. As a result, a large thermal stress or thermal strain is generated at the joint portion between the case 11 on the exhaust gas passage 12 side and the thermoelectric power generation unit 13 on the cooling water passage 31 side without complicating the structure and assembly. It can suppress effectively and can improve the power generation efficiency and heat recovery efficiency of the thermoelectric generator 10.

  In addition, in the present embodiment, not only expansion and contraction and axial displacement of the outer cylindrical heat transfer member 33 with respect to the case 11 by the heat-resistant elastic ring 56, but also the expansion and contraction diameter and the case of the outer cylindrical heat transfer member 33 accompanying thermal deformation. 11 is also allowed to be displaced in the radial direction, so that thermal stress and thermal strain at the joint portion of the case 11 and the outer cylindrical heat transfer member 33 are more effectively suppressed.

  Further, in the present embodiment, terminal chambers 57 and 58 positioned between the first side plate portions 11a and 11b and the second side plate portions 11c and 11d are formed in the case 11, and electrical wiring such as the element lead wire 38 is formed there. A connecting portion between the inner cylindrical heat transfer member 32 and the cooling water pipes 51 and 52 is accommodated. Therefore, they can be effectively protected from pitting and heat of water, mud, pebbles and the like.

  In addition, between the plurality of cartridge-like thermoelectric generator units 13, the electrical wiring such as the element lead wire 38 that is curved in a substantially U shape or arch shape can sufficiently follow the expansion and contraction due to thermal deformation in the longitudinal direction of the case 11. It becomes.

  As described above, according to the present embodiment, the structure and the assembly are not complicated, and between the case 11 that is a member on the high-temperature heat medium side and the thermoelectric power generation unit 13 that is a member on the low-temperature heat medium side. It is possible to provide the thermoelectric power generation apparatus 10 that can effectively suppress the occurrence of large stresses and strains and can meet the demands for downsizing and high efficiency in which power generation efficiency and heat recovery efficiency are increased.

(Second Embodiment)
FIG. 4 shows a schematic configuration of the thermoelectric generator according to the second embodiment of the present invention.

  In addition, the thermoelectric power generation apparatus of each embodiment described below is different from the first embodiment described above in that the arrangement of connection pipes connecting adjacent cooling water pipes 31 of a plurality of thermoelectric power generation units 13 is different. The configuration is similar to that of the first embodiment described above. Therefore, in the following description of each embodiment, the same or similar components as those of the preceding embodiment are denoted by the same reference numerals as the corresponding components in FIGS. The description will focus on the differences from the preceding embodiment.

  The thermoelectric generator 10 of the present embodiment is the first embodiment in that a plurality of the thermoelectric generator units 13 are arranged in parallel in the exhaust gas passage 12 so as to be substantially orthogonal to (intersect) the exhaust flow direction. It is the same.

  However, in the first embodiment, the cooling water pipes 51 and 52 that connect the cylindrical heat transfer members 32 inside the plurality of thermoelectric power generation units 13 are exposed to the outside of the case 11.

  On the other hand, in this embodiment, the inner cylindrical heat transfer member 32 and the case 11 include the cooling water pipes 51 and 52 that connect the inner cylindrical heat transfer members 32 of the plurality of thermoelectric power generation units 13 in series. The second side plate portions 11c and 11d are housed inside the case 11 on the outer side of the thermoelectric power generation unit 13.

  That is, in this embodiment, the cooling water pipes 51 and 52 that connect the plurality of inner cylindrical heat transfer members 32 are not exposed to the outside of the case 11.

  Also in the present embodiment, large stress and distortion are generated between the case 11 that is a member on the high temperature heat medium side and the thermoelectric power generation unit 13 that is a member on the low temperature heat medium side without complicating the structure and assembly. It is possible to provide the thermoelectric power generation apparatus 10 that can effectively suppress the generation and meet the demands for downsizing and high efficiency with increased power generation efficiency and heat recovery efficiency.

  In addition, in this embodiment, since the cooling water pipes 51 and 52 are not exposed to the outside of the case 11, the protection function for the pipe connection portions with the cooling water pipes 51 and 52 and the cylindrical heat transfer member 32 inside them is further improved. Can be improved.

(Third embodiment)
FIG. 5 shows a schematic configuration of a thermoelectric generator according to the third embodiment of the present invention.

  In the thermoelectric generator 10 of the present embodiment, as in the first embodiment, the inner cylindrical heat transfer member 32 and the case 11 are connected to the outer cylindrical heat transfer member 33 in the second side plate portions 11c and 11d. Terminal chambers 57 and 58 that communicate with the exhaust gas passage 12 through the sliding support gap portion on the outer side of the thermoelectric power generation unit 13 with respect to the heat-resistant elastic ring 56 that is the sliding support portion and inside the case 11. Is formed.

  However, in the first embodiment, the terminal chambers 57 and 58 may leak (gas leak) in the sliding gap portion between the case 11 and the outer cylindrical heat transfer member 33 to such an extent that breathing accompanying temperature change is possible. In contrast, in the present embodiment, the supercharging pressure of the internal combustion engine is selectively introduced into the terminal chambers 57 and 58 via the supercharging pressure introduction pipes 61 and 62 and the introduction control valve 63. It is like that.

  That is, in the vehicle in which the thermoelectric generator 10 of the present embodiment is used in combination with an internal combustion engine equipped with a turbocharger (not shown), the supercharged air pressurized to a positive pressure by the turbocharger in the terminal chambers 57 and 58. For example, by introducing supercharged air pressurized to a pressure equal to or higher than the exhaust gas pressure in the exhaust gas passage 12, leakage of exhaust gas from the exhaust gas passage 12 side into the terminal chambers 57 and 58 is suppressed. It has become so.

  Specifically, the supercharging pressure introduction pipes 61 and 62 merge on the upstream side and are connected to an intake pipe of an internal combustion engine (supercharged engine) equipped with a supercharger. The introduction control valve 63 is composed of a solenoid valve disposed on the upstream passage where the supercharging pressure introduction pipes 61 and 62 merge, and opens and closes in response to an opening / closing control signal from an electronic control unit (not shown). Then, by opening and closing the introduction control valve 63, the supercharged air is selected in the terminal chambers 57 and 58 from the intake pipe of the internal combustion engine (supercharged engine) equipped with the supercharger through the supercharging pressure introduction pipes 61 and 62. Introduced.

  Also in the present embodiment, large stress and distortion are generated between the case 11 that is a member on the high temperature heat medium side and the thermoelectric power generation unit 13 that is a member on the low temperature heat medium side without complicating the structure and assembly. It is possible to provide the thermoelectric power generation apparatus 10 that can effectively suppress the generation and meet the demands for downsizing and high efficiency with increased power generation efficiency and heat recovery efficiency.

  In addition, in the present embodiment, since leakage of exhaust gas from the exhaust gas passage 12 side into the terminal chambers 57 and 58 is effectively suppressed, electrical wiring such as the element lead wires 38 and the inner cylindrical heat transfer member 32 are suppressed. It is possible to prevent the connection portion between the coolant pipes 51 and 52 from being corroded by the exhaust gas component.

  In each of the above-described embodiments, each of the plurality of thermoelectric power generation units 13 includes the cylindrical inner cylindrical heat transfer member 32 and the outer cylindrical heat transfer member 33. It may have a circular cross-sectional shape or a flat tube. Further, the thermoelectric power generation unit 13 is not limited to one having a straight axis.

  Further, in each of the above-described embodiments, the heat medium passage 10 has an exhaust heat recovery function of recovering while converting the exhaust heat of the exhaust gas of the internal combustion engine into electric energy, and one heat medium passage is an exhaust gas passage. The other heat medium passage formed inside the thermoelectric power generation unit was used as a cooling medium passage through which engine cooling water passes. However, when the thermoelectric generator 10 is applied to other than the exhaust heat recovery of the internal combustion engine, it goes without saying that the heat medium is not limited to the exhaust gas and cooling water of the engine.

  As described above, the present invention effectively suppresses the occurrence of large stress and strain between the member on the high temperature heat medium side and the member on the low temperature heat medium side without complicating the structure and assembly. Thus, it is possible to provide a thermoelectric generator that can meet the demands for miniaturization and higher efficiency, and use the temperature difference between the two heat mediums while passing the heat medium on the high temperature side and the heat medium on the low temperature side. It is useful for all thermoelectric generators that generate electricity.

DESCRIPTION OF SYMBOLS 10 ... Thermoelectric generator, 11 ... Case, 11a, 11b ... 1st side board part, 11c, 11d ... 2nd side board part (sliding support part), 11f ... Annular flexible part, 11s ... Annular mounting plate, 12 ... Exhaust gas passage, 13 ... thermoelectric power generation unit, 30 ... cooling water passage, 30a ... cooling water inlet, 30b ... cooling water outlet, 31 ... cooling water passage (cooling medium passage), 32 ... inner cylindrical heat transfer member, 32a ... inner peripheral wall surface, 32b ... outer peripheral surface, 33 ... outer cylindrical heat transfer member, 33a ... inner peripheral surface, 33b ... outer peripheral wall surface, 33f, 33g ... outer peripheral surface portion (sliding surface portion), 34a, 34b ... thermoelectric element, 35 ... Thermoelectric element module, 36a, 36b ... Electrode, 38 ... Element lead wire, 41 ... Fin, 51, 52 ... Cooling water piping, 53 ... Cooling water piping on cooling water introduction side, 54 ... Cooling water on cooling water discharge side Piping, 55 ... flexible part, 56 ... heat-resistant elastic thread Grayed (sliding support portions) 57, 58 ... terminal chambers, 61, 62 ... supercharging pressure introduction pipe, 63 ... introduction control valve

Claims (1)

A case having one heat medium passage for passing the high temperature side heat medium, and a plurality of cylindrical thermoelectric power generation units forming the other heat medium passage for passing the low temperature side heat medium on the inner peripheral side, respectively , The thermoelectric generator unit is supported by the case so as to be substantially orthogonal to the flow direction of the heat medium on the high temperature side in the one heat medium passage,
Each of the thermoelectric generator units includes an inner cylindrical heat transfer member that forms the other heat medium passage, an outer cylindrical heat transfer member that surrounds the inner cylindrical heat transfer member, and the inner cylinder. A thermoelectric element module having a plurality of thermoelectric elements interposed between the outer heat transfer member and the outer cylindrical heat transfer member,
A flexible portion that absorbs expansion and contraction of the inner cylindrical heat transfer member with respect to the case by elastic deformation is provided on at least one of the inner cylindrical heat transfer member and the case of each of the thermoelectric generation units. As well as
The said casing, a plurality of sliding support unit slidably supported in the axial direction end portion of the at least one side of each of said outer tubular heat transfer member is provided in the thermoelectric power generation unit,
The case includes an outer plate portion which is airtightly coupled with the outer side of the thermoelectric power generation unit from the sliding support portion and the to respective inner tubular heat transfer member, the plurality of sliding support portions And an inner plate portion that supports each of the outer cylindrical heat transfer members, and a terminal that communicates with the sliding gaps of the plurality of sliding portions between the outer plate portion and the inner plate portion. A thermoelectric generator having a chamber formed therein .

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