JP6639426B2 - Thermoelectric generator - Google Patents

Description

  The present invention relates to an improved thermoelectric generator.

  There is a thermoelectric generator in which a thermoelectric conversion element is disposed between a high-temperature heat source and a low-temperature heat source, and the thermoelectric conversion element generates power based on a temperature difference. As a conventional technique related to a thermoelectric generator using a thermoelectric conversion element, there is a technique disclosed in Patent Document 1.

  Referring to FIG. FIG. 8 is a reprint of FIG. 4 of Patent Literature 1 and renumbered. The thermoelectric generator 100 disclosed in Patent Literature 1 has a core case 101, a pair of end plates 102, 102 closing both ends of the core case 101, and both ends supported by the end plates 102, 102. A first heat medium flow path 103 through which one heat medium flows, and a second heat medium flow path 104 provided in the core case 101 through the gap with respect to the first heat medium flow path 103 and through which the second heat medium flows. And a thermoelectric conversion element 105 that is disposed in a gap between the first heat medium flow path 103 and the second heat medium flow path 104 and generates electric power based on a temperature difference. The thermoelectric conversion element 105 generates power based on the temperature difference between the first heat medium and the second heat medium.

  By the way, when the temperature of the first heat medium is higher than that of the second heat medium, the first heat medium flow path 103 expands more greatly. Both ends of the first heat medium channel 103 are supported by a pair of end plates 102, 102. Therefore, when the first heat medium flow path 103 thermally expands, a force is applied to the end plates 102, 102 in a direction away from each other, and the load acts on the end plates 102, 102. It is desired to suppress the load applied to the end plates 102, 102.

JP 2014-86650 A

  An object of the present invention is to provide a technique for suppressing a load applied to an end plate supporting a flow path through which a heat medium on a high temperature side flows.

According to the first aspect of the present invention, a cylindrical core case, a pair of end plates closing both ends of the core case, and a first heat medium in which both ends are supported by these end plates and a first heat medium flows therein. A flow path, a second heat medium flow path provided in the core case through the gap with respect to the first heat medium flow path, through which the second heat medium flows, and a first heat medium flow path and a second heat medium flow path. A thermoelectric conversion element that is disposed in a gap between the heat medium flow paths and generates power based on a temperature difference,
At least one of the pair of end plates is connected to a first passage insertion portion into which an end of the first heat medium passage is inserted, and the first passage insertion portion and the core case are connected to each other. (1) having a thermal elongation absorbing portion that absorbs thermal elongation of the heat medium flow path,
The thermal elongation absorbing portion has an inclined portion that is inclined with respect to a flow direction of the first heat medium when at least the first heat medium flow path is extended by heat,
The thermoelectric generator is characterized in that the inclination angle of the inclined portion changes before and after the thermal elongation.

  As described in claim 2, preferably, the end plate supports a downstream end of the first heat medium flow path.

  As described in claim 3, preferably, the end plate has a plurality of thermal elongation absorbing portions.

  In the invention according to claim 1, the pair of end plates support both ends of the first heat medium flow path, and at least one of the pair of end plates has the end of the first heat medium flow path inserted therein. It has a first flow path insertion part, and a thermal expansion absorbing part that connects the first flow path insertion part and the core case and absorbs thermal expansion of the first heat medium flow path. The thermal elongation absorbing portion has an inclined portion that is inclined with respect to the flow direction of the first heat medium when at least the first heat medium flow path is extended by heat. Before and after.

  When the first heat medium flow path is heated by the high-temperature heat medium, the first heat medium flow path expands thermally. Due to the thermal expansion of the first heat medium flow path, a force is applied to the end plate in a direction away from the core case with respect to the flow direction of the first heat medium. Here, the thermal elongation absorbing portion in the end plate has an inclined portion. Therefore, the end of the inclined portion on the end plate side is displaced away from the core case, and the inclined portion is inclined in a direction in which the inclination with respect to the flow direction of the first heat medium becomes small. When the inclined portion is inclined, the length of the thermal elongation absorbing portion becomes longer based on the flow direction of the first heat medium. That is, the thermal expansion of the first heat medium flow path is absorbed by the deformation of the thermal expansion absorbing portion forming a part of the end plate. Therefore, the load applied to the end plate can be suppressed.

  In the invention according to claim 2, the end plate having the thermal elongation absorbing portion supports the downstream end of the first heat medium flow path. The downstream end of the first heat medium flow path has a lower temperature than the upstream end. Therefore, as compared with the case where the end plate having the thermal elongation absorbing portion is arranged at the end on the upstream side, the durability of the end plate under use conditions is increased.

  In the invention according to claim 3, the end plate has a plurality of thermal elongation absorbing portions. Therefore, the thermal elongation of the first heat medium flow path can be dispersed to the plurality of thermal elongation absorbing portions, and it is possible to cope with larger thermal elongation.

1 is a perspective view of an exhaust gas power generation device according to Embodiment 1 of the present invention. FIG. 2 is a perspective view of a thermoelectric generator mounted on the exhaust gas power generator shown in FIG. 1. FIG. 3 is a sectional view taken along line 3-3 of FIG. 2. FIG. 3 is an exploded perspective view of an end plate of the thermoelectric generator shown in FIG. FIG. 4 is an enlarged view of a main part of the thermoelectric generator shown in FIG. 3. FIG. 3 is an operation diagram of the thermoelectric generator shown in FIG. 2. FIG. 8 is an operation diagram of the exhaust gas power generation device according to Embodiment 2 of the present invention. It is sectional drawing of the thermoelectric generator by a prior art.

An embodiment of the present invention will be described below with reference to the accompanying drawings. In the description, Up indicates the upstream side of the exhaust gas flow path, and Dn indicates the downstream side.
<Example 1>

  Please refer to FIG. FIG. 1 shows an exhaust gas power generation device 10 that generates power using exhaust gas (first heat medium) of a vehicle. The exhaust gas power generation device 10 includes an exhaust gas introduction member 11 into which exhaust gas is introduced, a thermoelectric generation device 20 connected to the exhaust gas introduction member 11, and a valve that opens and closes a flow path on the downstream side of the thermoelectric generation device 20. The chamber 12 includes an actuator 13 connected to the thermoelectric generator 20, an exhaust gas passage 14 arranged in parallel with the thermoelectric generator 20, and an exhaust gas discharge member 15 connected to the valve chamber 12.

  The actuator 13 has a rod 16 that can move forward and backward. A rotatable shaft member 17 is provided in the valve chamber 12, and an arc-shaped plate 18 that can swing around the shaft member 17 as a rotation center is provided inside the valve chamber 12. The end of the shaft member 17 constitutes a part of a crank mechanism, and the plate 18 swings by the advance and retreat of a rod 16 provided on the actuator 13. The plate 18 opens and closes a boundary 19 between the thermoelectric generator 20 and the valve chamber 12.

  The exhaust gas is introduced from an exhaust gas inlet 11 a of the exhaust gas introduction member 11. Since the thermoelectric generator 20 is provided immediately below the exhaust gas inlet 11a, most of the exhaust gas flows into the thermoelectric generator 20. The cooling water (second heat medium) is introduced from a lower part of the thermoelectric generator 20. The thermoelectric generator 20 generates power based on the temperature difference between the exhaust gas and the cooling water introduced into the thermoelectric generator 20.

  The exhaust gas that has passed through the thermoelectric generator 20 passes through the valve chamber 12 and is discharged from an exhaust gas outlet 15 a of the exhaust gas discharging member 15. The cooling water that has passed through the thermoelectric generator 20 passes through the inside of the actuator connection member 13b, and is discharged from the cooling water discharge port 13a.

  When the cooling water passing through the inside of the actuator connection member 13b reaches a predetermined temperature, the rod 16 advances toward the shaft member 17. As the rod 16 advances, the plate 18 swings and the boundary 19 is closed. Since the downstream side of the thermoelectric generator 20 is closed, most of the exhaust gas passes through the exhaust gas passage 14. The exhaust gas that has passed through the exhaust gas passage 14 is discharged from an exhaust gas outlet 15 a of the exhaust gas discharging member 15. Hereinafter, details of the thermoelectric generator will be described.

  Please refer to FIG. 2 and FIG. The thermoelectric generator 20 includes a cylindrical core case 21, a pair of upstream end plates 30 and a downstream end plate 40 closing both ends of the core case 21, and both ends supported by the end plates 30, 40. The first and second exhaust gas passages 50 and 60 (first heat medium passages 50 and 60) through which the exhaust gas flows, and the first and second exhaust gas passages 50 and 60 via a gap. A cooling water flow path 22 (second heat medium flow path 22) provided in the core case 21 and through which cooling water flows, and a gap between the first and second exhaust gas flow paths 50 and 60 and the cooling water flow path 22. And a plurality of thermoelectric converters 70 arranged in the same manner.

  The core case 21 is configured by fitting the upstream core case 21b to the downstream core case 21a. The first exhaust gas flow path 50 includes a cylindrical first case 51, first exhaust gas fins 52, 52 disposed inside the first case 51 in two layers, and a first exhaust gas fin 52. A first separator 53 disposed between the fins 52, 52.

  The second exhaust gas channel 60 has the same configuration as the first exhaust gas channel 50. The second exhaust gas passage 60 includes a cylindrical second case 61, second exhaust gas fins 62, 62 disposed in two layers inside the second case 61, and a second exhaust gas fin 62. A second separator 63 disposed between the fins 62.

  Please refer to FIG. The outer periphery of the first case 51 is covered with the first cover member 23 with a gap for arranging the thermoelectric conversion unit 70. Similarly, the outer periphery of the second case 61 is covered with the second cover member 24 with a gap for arranging the thermoelectric converter 70.

  A plurality of thermoelectric converters 70 are mounted between the first case 51 and the first cover member 23. The thermoelectric conversion section 70 includes a high-temperature side electrode section 71 in contact with the first case 51, a low-temperature side electrode section 72 in contact with the first cover member 23, and a high-temperature side and low-temperature side electrode section 71, 72 connected to a thermoelectric conversion element 73.

  A plurality of thermoelectric converters 70 are also provided between the second case 61 and the second cover member 24. The high-temperature side electrode portion 71 contacts the second case 61 and the low-temperature side electrode portion 72 contacts the second cover member 24, and a thermoelectric conversion element 73 is connected between the high-temperature side electrode portion 71 and the low-temperature side electrode portion 72.

  A first cooling water fin 25 is attached to an outer peripheral surface of the first cover member 23. Similarly, a second cooling water fin 26 is attached to the outer peripheral surface of the second cover member 24.

  The plurality of thermoelectric converters 70 generate electric power based on the temperature difference between the exhaust gas flowing through the first and second exhaust gas passages 50 and 60 and the cooling water flowing through the cooling water passage 22.

  Please refer to FIG. 3 and FIG. Next, details of the upstream and downstream end plates 30 and 40 will be described. The upstream end plate 30 and the downstream end plate 40 have the same configuration.

  The upstream end plate 30 includes an upstream insertion portion 31 (first flow passage insertion portion 31) into which the upstream end portions 50a, 60a of the first and second exhaust gas flow passages 50, 60 are inserted. The upstream thermal elongation absorbing part 32, which is connected to the upstream insertion part 31 and absorbs the thermal elongation of the first and second exhaust gas passages 50, 60, is connected to the upstream thermal elongation absorbing part 32 and the core case 21. And an upstream body 33.

  The downstream end plate 40 includes a downstream insertion portion 41 (first flow passage insertion portion 41) into which the downstream end portions 50b, 60b of the first and second exhaust gas flow passages 50, 60 are inserted. The downstream-side thermal expansion absorbing section 42, which is connected to the downstream-side insertion section 41 and absorbs thermal expansion of the first and second exhaust gas passages 50, 60, is connected to the downstream-side thermal expansion absorbing section 42 and the core case 21. And a downstream side main body 43.

  Please refer to FIG. 4 and FIG. Hereinafter, details of the downstream end plate 40 will be described. The details of the upstream end plate 30 are the same as the details of the downstream end plate 40, and a description thereof will be omitted.

  The downstream-side insertion portion 41 has a substantially U-shape in a cross-sectional view, and has an insertion bottom portion 41a that extends substantially vertically with respect to the first exhaust gas flow path 50, and an outer peripheral end of the insertion bottom portion 41a. And an insertion outer peripheral portion 41b extending downstream from the insertion portion, and an insertion inner peripheral portion 41c extending downstream from the inner peripheral end of the insertion bottom portion 41a.

  The downstream-side thermal expansion absorbing portion 42 has a crank shape in a cross-sectional view, and has a thermal expansion bottom 42a (inclined portion 42a) extending substantially vertically to the first exhaust gas flow path 50, and an outer periphery of the thermal expansion bottom 42a. A thermal expansion outer peripheral portion 42b extending downstream from the side end and a thermal expansion inner peripheral portion 42c extending upstream from the inner peripheral end of the thermal expansion bottom portion 42a.

  The thermal elongation bottom portion 42a is inclined substantially vertically with respect to the flow direction of the exhaust gas. The inclination angle θ of the thermal expansion bottom portion 42a changes before and after thermal expansion of the first exhaust gas flow path 50. Details will be described later.

  The downstream-side main body 43 has a substantially J-shape in cross-sectional view, and has a main body bottom 43a extending substantially vertically to the first exhaust gas flow path 50, and an upstream end from an outer peripheral end of the main body bottom 43a. And a main body inner peripheral portion 43c extending upstream from the inner peripheral end of the main body bottom portion 43a.

  Please refer to FIG. The downstream end 50b of the first case 51 of the first exhaust gas passage 50 is inserted into and joined to the insertion inner peripheral portion 41c of the downstream insertion portion 41. The insertion outer peripheral portion 41b and the thermally elongated outer peripheral portion 42b are joined to each other. The thermal expansion inner peripheral portion 42c and the main body inner peripheral portion 43c are joined to each other. The main body outer peripheral portion 43b and the core case 21 are joined.

  Next, the operation and effect of the present invention will be described.

  Please refer to FIG. 4 and FIG. The downstream end plate 40 includes a downstream insertion portion 41, a downstream thermal expansion absorbing portion 42, and a downstream main body portion 43. The downstream-side thermal expansion absorbing section 42 has a thermal expansion bottom 42a inclined with respect to the flow direction of the exhaust gas.

  As shown by the arrow (a), when the first exhaust gas passage 50 is heated by the exhaust gas, the first exhaust gas passage 50 expands thermally. Due to the thermal expansion of the first exhaust gas passage 50, a downstream force is applied to the downstream insertion portion 41 with reference to the flow direction of the exhaust gas. As shown by the arrow (b), the thermal expansion outer peripheral portion 42b is pulled downstream by the insertion outer peripheral portion 41b. When the exhaust gas flows, the core case 21 also thermally expands. As shown by the arrow (c), the thermal expansion inner peripheral portion 42 c is pulled downstream by the downstream main body 43 joined to the core case 21. However, the first exhaust gas passage 50 through which the high-temperature exhaust gas flows has a larger thermal expansion than the core case 21. Therefore, the thermal expansion bottom portion 42a is inclined in a direction in which the inclination angle θ with respect to the flow direction of the exhaust gas becomes smaller. When the thermal expansion bottom portion 42a is inclined, the length L of the downstream-side thermal expansion absorption portion 42 becomes longer based on the flow direction of the exhaust gas.

  That is, the thermal expansion of the first exhaust gas passage 50 is absorbed by the deformation of the downstream thermal expansion absorbing portion 42 that forms a part of the downstream end plate 40. Therefore, the load applied to the downstream end plate 40 can be suppressed.

  When the first exhaust gas passage 50 and the core case 21 undergo thermal expansion, the main body bottom 43a of the downstream main body 43 is also slightly inclined. Therefore, the downstream side main body 43 also has an effect of absorbing thermal elongation. That is, the inclined portion according to the present invention is not limited to only a portion that is inclined with respect to the flow direction of the exhaust gas before thermal expansion. Even if the portion extends vertically with respect to the flow direction of the exhaust gas before the thermal elongation, the portion can be said to be an inclined portion if the inclination angle changes before and after the thermal elongation.

  The upstream end plate 30 has the same operation and effect as the downstream end plate 40. Description is omitted.

  In the present embodiment, the upstream and downstream end plates 30 and 40 have the thermal expansion absorbing portions 32 and 42, respectively, but the thermal expansion absorbing portions 32 and 42 have one of the upstream and downstream sides. It may be provided on the end plates 30 and 40.

  Please refer to FIG. The downstream ends 50b, 60b of the first and second exhaust gas passages 50, 60 have a lower temperature than the upstream ends 50a, 60a. Therefore, when the end plate 40 having the thermal elongation absorbing portion 42 is provided at the downstream end portions 50b and 60b, the durability of the end plate 40 in use conditions is increased.

  In addition, the outer peripheral part 42b and the inner peripheral part 42c of the downstream thermal elongation absorption part 42 are raised in the flow direction of the exhaust gas. Therefore, at the time of assembling the downstream end plate 40, the downstream thermal expansion absorbing portion 42 is easily aligned with the downstream insertion portion 41 and the downstream main body portion 43, and the mutual connection is facilitated.

<Example 2>
Next, a second embodiment of the present invention will be described. In Example 2, the number of thermal elongation absorbing portions is different. Other configurations are the same as those of the first embodiment, and the reference numerals are diverted and description thereof is omitted.

  Please refer to FIG. On the upstream side of the downstream-side thermal elongation absorber 42, a second thermal elongation absorber 82 and a third thermal elongation absorber 83 are arranged so as to overlap each other.

  The second thermal elongation absorbing portion 82 has a substantially U shape in a cross-sectional view, and has a second thermal elongate bottom portion 82a extending substantially perpendicular to the first exhaust gas flow path 50, and an outer peripheral side of the second thermal elongation bottom portion 82a. A second thermal expansion outer peripheral portion 82b extending upstream from the end of the second thermal expansion, and a second thermal expansion inner peripheral portion 82c extending upstream from the inner peripheral end of the second thermal expansion bottom portion 82a.

  Similarly, the third thermal elongation absorbing portion 83 has a substantially U shape in a cross-sectional view, and extends substantially vertically to the first exhaust gas flow path 50. And a third thermal expansion inner peripheral portion 83c extending upstream from an inner peripheral end of the third thermal expansion bottom portion 83a. .

  The thermal expansion inner peripheral portion 42c and the second thermal expansion inner peripheral portion 82c are joined. The second thermal extension outer peripheral portion 82b and the third thermal extension outer peripheral portion 83b are joined. The third thermal expansion inner peripheral portion 83c and the main body inner peripheral portion 43c are joined.

  The predetermined effect of the present invention can be obtained also in the thermoelectric generator 20A. Furthermore, according to the thermoelectric generator 20A, the following specific effects can be obtained by the above configuration.

  The downstream end plate 40A has three thermal elongation absorbing portions 42, 82, 83. Therefore, the thermal expansion of the first and second exhaust gas passages 50 and 60 is absorbed by the thermal expansion absorbing portions 42, 82 and 83 that deform into an accordion shape. Since each of the thermal expansion absorbing portions 42, 82, 83 changes, it is possible to cope with a larger thermal expansion. Note that a plurality of thermal elongation absorbing portions may be provided on the upstream end plate 30 (see FIG. 3).

  Although the thermoelectric generator according to the present invention has been described taking an exhaust gas generator as an example, the embodiment of the thermoelectric generator is not limited to this type. That is, the present invention is not limited to the embodiments as long as the functions and effects of the present invention are exhibited.

  The thermoelectric generator of the present invention is suitable for mounting on an exhaust gas generator.

10 Exhaust gas power generation device 20 Thermoelectric power generation device 21 Core case (21a downstream side, 21b upstream side)
Reference Signs List 22 cooling water flow path 30 upstream end plate 31 insertion part 32 thermal expansion absorbing part 33 main body part 40 downstream end plate 41 downstream insertion part (41a bottom part 41b outer peripheral part 41c) … Inner circumference)
42: Downstream thermal elongation absorption section (42a: bottom, 42b: outer circumference, 42c: inner circumference)
43: Downstream main body (43a: bottom, 43b: outer circumference, 43c: inner circumference)
50: first exhaust gas flow path (first heat medium flow path)
60... Second exhaust gas flow path (first heat medium flow path)
70 thermoelectric conversion part 82 second thermal expansion absorption part (82a bottom part, 82b outer peripheral part, 82c inner peripheral part)
83: third thermal elongation absorbing portion (83a: bottom portion, 83b: outer peripheral portion, 83c: inner peripheral portion)

Claims (3)

A tubular core case, a pair of end plates for closing both ends of the core case, a first heat medium flow path in which both ends are supported by these end plates and a first heat medium flows therein; A second heat medium flow path provided in the core case through the gap with respect to the flow path and through which the second heat medium flows, and a gap between the first heat medium flow path and the second heat medium flow path And a thermoelectric conversion element that is arranged and generates electric power based on the temperature difference.
At least one of the pair of end plates is connected to a first passage insertion portion into which an end of the first heat medium passage is inserted, and the first passage insertion portion and the core case are connected to each other. (1) having a thermal elongation absorbing portion that absorbs thermal elongation of the heat medium flow path,
The thermal elongation absorbing portion has an inclined portion that is inclined with respect to a flow direction of the first heat medium when at least the first heat medium flow path is extended by heat,
A thermoelectric generator, wherein the inclination angle of the inclined portion changes before and after the thermal elongation.   The thermoelectric generator according to claim 1, wherein the end plate supports a downstream end of the first heat medium flow path.   3. The thermoelectric generator according to claim 1, wherein the end plate has a plurality of thermal elongation absorbing portions based on a flow direction of the first heat medium. 4.

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