Thermoelectric conversion element and heat insulation structure of piping

Abstract

A thermoelectric conversion element 1 comprises: an insulating resin element body 2 extending in a first direction; and a first thermoelectric conversion member 3 containing a carbon material as a conductive material. The first thermoelectric conversion member 3 has a first electromotive section 31. The first electromotive section 31 is disposed inside the resin element body 2. The first electromotive section 31 has a predetermined length in the first direction. The first electromotive section 31 generates electromotive force by means of a temperature difference in the first direction.

Description

Thermoelectric conversion element and piping insulation structure

[0001] The present invention relates to a thermoelectric conversion element and a heat insulating structure for piping.

[0002] A thermoelectric conversion element has been proposed that includes a heat insulating material and a thread-like thermoelectric conversion member sewn into the heat insulating material (see Patent Document 1 below).

[0003] International Publication No. 2023 / 127590

[0004] In the thermoelectric conversion element described in the above-mentioned Patent Document 1, the thermoelectric conversion member needs to be sewn into the heat insulating material, which is problematic in that construction is difficult.

[0005] The present invention provides a thermoelectric conversion element that can be easily installed, and a heat insulating structure for a pipe equipped with the thermoelectric conversion element.

[0006] The present invention [1] includes a thermoelectric conversion element comprising an insulating resin body extending in a first direction and a thermoelectric conversion member containing a carbon material as a conductive material, the thermoelectric conversion member being disposed inside the resin body, having a predetermined length in the first direction, and having an electromotive portion that generates an electromotive force in response to a temperature difference in the first direction.

[0007] According to this configuration, the thermoelectric conversion element includes a thermoelectric conversion member containing a carbon material as a conductive material, and an insulating resin body. The electromotive portion of the thermoelectric conversion member is disposed within the resin body.

[0008] Therefore, the thermoelectric conversion element can be made lighter, and the electromotive part of the thermoelectric conversion member can be disposed within the object of installation by the simple process of drilling a hole in the object of installation and embedding the resin element in the object of installation.

[0009] This allows the thermoelectric conversion element to be easily installed on the installation target.

[0010] The present invention [2] includes the thermoelectric conversion element of the above [1], further comprising an electrode disposed outside the resin body and electrically connected to the thermoelectric conversion member.

[0011] The present invention [3] includes the thermoelectric conversion element of [1] or [2] above, which can be embedded in a thermal insulating material, and in a state where the thermoelectric conversion element is embedded in the thermal insulating material, the electromotive portion extends in the thickness direction of the thermal insulating material.

[0012] The present invention [4] includes the thermoelectric conversion element according to any one of the above [1] to [3], wherein the thermoelectric conversion member is a P-type thermoelectric conversion member.

[0013] The present invention [5] includes the thermoelectric conversion element of the above [4], further comprising a second thermoelectric conversion member containing a carbon material as a conductive material, the second thermoelectric conversion member being an N-type thermoelectric conversion member, the second thermoelectric conversion member being disposed inside the resin body, having a predetermined length in the first direction, and having a second electromotive portion that generates an electromotive force due to a temperature difference in the first direction, the second electromotive portion being electrically connected to the electromotive portion.

[0014] With this configuration, the thermoelectric conversion member behaves as a P-type semiconductor and the second thermoelectric conversion member behaves as an N-type semiconductor, and the electromotive part and the second electromotive part are electrically connected, so that the electromotive part and the second electromotive part form one cell structure of a π-type thermoelectric conversion element.

[0015] As a result, the electromotive force can be increased.

[0016] The present invention [6] includes the thermoelectric conversion element according to the above [5], which has a plurality of cells each including the electromotive portion and the second electromotive portion.

[0017] According to this configuration, the electromotive force can be increased by the multiple cell structure.

[0018] The present invention [7] includes the thermoelectric conversion element according to the above [5] or [6], wherein the second electromotive portion is covered with an insulating layer, and the electromotive portion is in contact with the insulating layer.

[0019] According to this configuration, the electromotive part and the second electromotive part can be disposed close to each other.

[0020] Therefore, the thermoelectric conversion element can be made smaller.

[0021] The present invention [8] includes the thermoelectric conversion element of any one of [1] to [4] above, further comprising a metal wire disposed inside the resin body and electrically connected to the electromotive portion.

[0022] The present invention [9] includes the thermoelectric conversion element according to the above [8], in which the wire is covered with an insulating layer, and the electromotive portion is in contact with the insulating layer.

[0023] The present invention

[10] includes a heat insulating structure for a pipe, the heat insulating structure including a pipe, a heat insulating material covering the pipe, and a thermoelectric conversion element according to any one of [1] to [9] above embedded in the heat insulating material.

[0024] With this configuration, the electromotive portion of the thermoelectric conversion member can be disposed within the heat insulating material by a simple process of drilling a hole in the heat insulating material covering the piping and embedding the resin body of the thermoelectric conversion element in the heat insulating material.

[0025] This allows the thermoelectric conversion element to be easily attached to the heat insulating material that covers the pipe.

[0026] The present invention

[11] includes the heat insulating structure for piping according to the above

[10] , further comprising a second heat insulating material disposed on top of the heat insulating material and covering the thermoelectric conversion element.

[0027] With such a configuration, there is a possibility that the heat insulating properties will be reduced in the portion where the thermoelectric conversion element is embedded.

[0028] In this regard, by covering the thermoelectric conversion element with the second heat insulating material, it is possible to compensate for the decrease in heat insulating properties.

[0029] The present invention

[12] includes the heat insulating structure for piping according to the above

[11] , further comprising an exterior member that covers the heat insulating material, the exterior member having an opening, and the thermoelectric conversion element being disposed in the opening.

[0030] According to this configuration, the thermoelectric conversion element can be electrically connected to an external electronic device through the opening in the exterior member.

[0031] The present invention

[13] includes the heat insulating structure for piping according to the above

[12] , further comprising a cover that closes the opening of the exterior member.

[0032] With this configuration, closing the cover can prevent the heat insulating material in the opening from getting wet.

[0033] According to the thermoelectric conversion element of the present invention, the thermoelectric conversion element can be easily installed on the installation target.

[0034] According to the heat insulating structure for piping of the present invention, the thermoelectric conversion element can be easily attached to the heat insulating material around the piping.

[0035] FIG. 1 is a perspective view of one embodiment of a thermoelectric conversion element of the present invention. FIG. 2 is a cross-sectional view of the thermoelectric conversion element shown in FIG. 1. FIG. 3 is a cross-sectional view showing a "heat insulating structure for piping" including the thermoelectric conversion element shown in FIG. 1. FIG. 4 is an explanatory diagram for explaining modified example (1). FIG. 5 is an explanatory diagram for explaining modified example (2). FIG. 6 is an explanatory diagram for explaining modified example (3). FIG. 7 is an explanatory diagram for explaining modified example (4). FIG. 8 is an explanatory diagram for explaining modified example (5). FIG. 9 is an explanatory diagram for explaining modified example (6).

[0036] 1 is an element for converting a temperature difference into electricity. The thermoelectric conversion element 1 includes a resin body 2, a first thermoelectric conversion member 3, a second thermoelectric conversion member 4, and a plurality of electrodes 5 and 6.

[0037] (1) Resin Body The resin body 2 extends in a first direction. The shape of the resin body 2 is not limited. The resin body 2 has, for example, a cylindrical shape. The resin body 2 encapsulates the first electromotive unit 31 and the second electromotive unit 41 together. The first electromotive unit 31 and the second electromotive unit 41 will be described later. The resin body 2 is made of an insulating resin. Examples of materials for the resin body 2 include thermoplastic resin and thermosetting resin.

[0038] Examples of thermoplastic resins include polyvinyl chloride (PVC), polystyrene (PS), styrene-based resins (HIPS, SAN, ABS), acrylic resins (PMMA), polyethylene (PE), polypropylene (PP), polycarbonate (PC), modified polyetherphenyl (m-PPE), polyacetal (POM), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyamide (PA), polyarylate (PAR), polysulfone (PSU), polyethersulfone (PES), thermoplastic polyimides (TPI, PEI, PAI), polyphenylene sulfide (PPS), polyetheretherketone (PEEK), liquid crystal polymers (LCP), and fluororesins (PTFE, PFA, PVDF, ETFE).

[0039] Examples of thermosetting resins include epoxy resin (EP), silicone resin (SI), diallyl phthalate resin (PDAP), phenol resin (PF), unsaturated polyester resin (UP), polyimide resin (PI), polyurethane resin (PUR), melamine resin (MF), urea resin (UF), and thermosetting acrylic resin (PAR).

[0040] The material of the resin body 2 is preferably a thermosetting resin, more preferably an epoxy resin.

[0041] The length L1 of the resin body 2 in the first direction is, for example, 10 mm or more, or preferably 20 mm or more. When the length L1 of the resin body 2 in the first direction is equal to or greater than the above-mentioned lower limit, a temperature difference in the first direction can be ensured.

[0042] There is no upper limit to the length L1 of the resin body 2 in the first direction, and the length L1 of the resin body 2 in the first direction is, for example, 80 mm or less.

[0043] The maximum length L2 of the resin body 2 in the direction perpendicular to the first direction is, for example, 1 mm or more, preferably 3 mm or more. When the maximum length L2 of the resin body 2 in the direction perpendicular to the first direction is equal to or greater than the above-mentioned lower limit, the rigidity of the resin body 2 can be ensured, and the handleability of the thermoelectric conversion element 1 can be improved.

[0044] The maximum length L2 of the resin body 2 in the direction perpendicular to the first direction is, for example, 20 mm or less, preferably 15 mm or less. When the maximum length L2 of the resin body 2 in the direction perpendicular to the first direction is equal to or less than the above upper limit, excessive enlargement of the resin body 2 can be prevented.

[0045] The ratio (L2 / L1) of the "maximum length L2 of the resin body 2 in the direction perpendicular to the first direction" to the "length L1 of the resin body 2 in the first direction" is, for example, 0.04 or more, preferably 0.25 or more. When the ratio (L2 / L1) is equal to or greater than the above lower limit, the rigidity of the resin body 2 can be ensured, and the handleability of the thermoelectric conversion element 1 can be improved.

[0046] The ratio (L2 / L1) is, for example, not more than 2, or preferably not more than 2. When the ratio (L2 / L1) is not more than the above upper limit, the resin body 2 can be prevented from becoming excessively large.

[0047] There are no limitations on the thermal conductivity of the resin body 2. The thermal conductivity of the resin body 2 is, for example, 0.1 W / m·K to 0.8 W / m·K, or preferably 0.1 W / m·K to 0.4 W / m·K.

[0048] The density of the resin body 2 is, for example, 500 kg / m ３ More than 800 kg / m ３ That's all.

[0049] When the density of the resin body 2 is equal to or greater than the lower limit, the hardness of the resin body 2 can be ensured, and deformation of the thermoelectric conversion element 1 can be suppressed.

[0050] There is no upper limit to the density of the resin body 2. The density of the resin body 2 is, for example, 1500 kg / m ３ The following is the result.

[0051] (2) First Thermoelectric Conversion Member At least a portion of the first thermoelectric conversion member 3 is disposed inside the resin body 2. The first thermoelectric conversion member 3 extends in a first direction. In this embodiment, the first thermoelectric conversion member 3 is thread-shaped. The shape of the first thermoelectric conversion member 3 is not limited. The first thermoelectric conversion member 3 may be, for example, strip-shaped, needle-shaped, or rod-shaped.

[0052] The diameter of the first thermoelectric conversion member 3 is, for example, 150 μm or more, preferably 300 μm or more. When the diameter of the first thermoelectric conversion member 3 is equal to or greater than the above-mentioned lower limit, the electromotive force of the first thermoelectric conversion member 3 can be increased.

[0053] The "diameter of the first thermoelectric conversion member 3" refers to the minimum length of the first thermoelectric conversion member 3 in a direction perpendicular to the extension direction of the first thermoelectric conversion member 3 (the radial direction of the first thermoelectric conversion member 3). Specifically, when the cross section of the first thermoelectric conversion member 3 in the radial direction is circular, the "diameter of the first thermoelectric conversion member 3" refers to the diameter of the circle. When the cross section of the first thermoelectric conversion member 3 in the radial direction is elliptical, the "diameter of the first thermoelectric conversion member 3" refers to the length of the minor axis of the ellipse. When the first thermoelectric conversion member 3 is ribbon-shaped, the "diameter of the first thermoelectric conversion member 3" refers to the thickness of the first thermoelectric conversion member 3.

[0054] The diameter of the first thermoelectric conversion member 3 is, for example, 3000 μm or less, preferably 1500 μm or less, or more preferably 1000 μm or less.

[0055] The first thermoelectric conversion member 3 has a first electromotive part 31. The entire first electromotive part 31 is disposed inside the resin body 2. The first electromotive part 31 extends in a first direction. One end of the first electromotive part 31 is connected to the electrode 5. The first electromotive part 31 generates an electromotive force due to a temperature difference in the first direction. The first electromotive part 31 has a predetermined length in the first direction.

[0056] The length of the first electromotive part 31 in the first direction is, for example, 10 mm or more, preferably 20 mm or more. When the length of the first electromotive part 31 in the first direction is equal to or greater than the above-mentioned lower limit, the electromotive force can be increased. There is no upper limit to the length of the first electromotive part 31 in the first direction. The length of the first electromotive part 31 in the first direction is, for example, 80 mm or less.

[0057] The first thermoelectric conversion member 3 is a P-type thermoelectric conversion member. The first thermoelectric conversion member 3 behaves as a P-type semiconductor. Specifically, the first thermoelectric conversion member 3 contains a carbon material as a conductive material, and, as necessary, a binder and a P-type dopant. By containing a carbon material as a conductive material in the first thermoelectric conversion member 3, it is possible to reduce the weight of the thermoelectric conversion element.

[0058] The carbon material provides electrical conductivity to the first thermoelectric conversion member 3 .

[0059] Examples of the carbon material include carbon nanotubes, carbon nanofibers, graphene, graphene nanoribbons, and fullerene nanowhiskers. A preferred example of the carbon material is carbon nanotubes. That is, the first thermoelectric conversion member 3 preferably contains carbon nanotubes and, as necessary, a binder and a P-type dopant. When the carbon material is carbon nanotubes, the electrical properties of the carbon nanotubes as a P-type semiconductor can be utilized to efficiently produce the first thermoelectric conversion member 3.

[0060] The first thermoelectric conversion member 3 may contain a conductive material other than a carbon material as the conductive material.

[0061] Examples of conductive materials other than carbon materials include semiconductor materials and conductive polymers.

[0062] Examples of semiconductor materials include bismuth (Bi), tellurium (Te), antimony (Sb), cobalt (Co), zinc (Zn), silicon (Si), germanium (Ge), iridium (Ir), lead (Pb), and alloys thereof, skutterudite, and constantan. Semiconductor materials may contain metal elements, but due to their crystalline structure or the combination of elements in the alloy, they have a higher resistance than metals and behave as semiconductors. Semiconductor materials may also be semiconductor whiskers.

[0063] Examples of conductive polymers include polyacetylene, poly(p-phenylene vinylene), polypyrrole, polythiophene, polyaniline, poly(p-phenylene sulfide), a composite of poly(3,4-ethylenedioxythiophene) and polystyrene sulfonic acid (PEDOT:PSS), a composite of poly(3,4-ethylenedioxythiophene) and polymethylsiloxane propylsulfonate (PEDOT:PSiPS), and a composite of poly(3,4-ethylenedioxythiophene) and paratoluenesulfonic acid (PEDOT:Tos).

[0064] The proportion of the conductive material in the first thermoelectric conversion member 3 is, for example, 30 mass % or more, preferably 40 mass % or more, and more preferably 50 mass % or more. When the proportion of the conductive material is equal to or more than the above lower limit, the conductivity of the first thermoelectric conversion member 3 can be ensured.

[0065] There is no upper limit to the proportion of the conductive material in the first thermoelectric conversion member 3. The proportion of the conductive material in the first thermoelectric conversion member 3 is, for example, 100 mass % or less, preferably 70 mass % or less, and more preferably 60 mass % or less.

[0066] When the first thermoelectric conversion member 3 contains a binder, the proportion of the conductive material in the first thermoelectric conversion member 3 is, for example, 40 parts by mass or more, preferably 60 parts by mass or more, per 100 parts by mass of the binder. When the proportion of the conductive material is equal to or more than the above lower limit, the conductivity of the first thermoelectric conversion member 3 can be ensured.

[0067] When the first thermoelectric conversion member 3 contains a binder, the proportion of the conductive material in the first thermoelectric conversion member 3 is, for example, 250 parts by mass or less, preferably 150 parts by mass or less, per 100 parts by mass of the binder. When the proportion of the conductive material is equal to or less than the above upper limit, the proportion of the binder can be secured, and the strength of the first thermoelectric conversion member 3 can be secured.

[0068] The binder binds the conductive material. When the conductive material is carbon nanotubes, the binder binds the carbon nanotubes. Examples of the binder include insulating resins and conductive resins.

[0069] Examples of insulating resins include polyethylene glycol, epoxy resin, acrylic resin, urethane resin, polystyrene resin, and polyvinyl resin. Examples of polyvinyl resins include polyvinyl chloride, polyvinylpyrrolidone, polyvinyl alcohol, and polyvinyl acetate.

[0070] Examples of conductive resins include polyacetylene, poly(p-phenylene vinylene), polypyrrole, polythiophene, polyaniline, poly(p-phenylene sulfide), and poly(3,4-ethylenedioxythiophene).

[0071] As the binder, preferably, an insulating resin is used, and more preferably, polyethylene glycol is used.

[0072] The proportion of the binder in the first thermoelectric conversion member 3 is, for example, 30 mass % or more, or preferably 40 mass % or more. When the proportion of the binder is equal to or more than the above lower limit, the tensile strength of the first thermoelectric conversion member 3 can be ensured.

[0073] The proportion of the binder in the first thermoelectric conversion member 3 is, for example, 70 mass % or less, preferably 60 mass % or less. When the proportion of the binder is equal to or less than the above upper limit, the proportion of the conductive material can be ensured, and the conductivity of the first thermoelectric conversion member 3 can be ensured.

[0074] The proportion of the binder in the first thermoelectric conversion member 3 is, for example, 40 parts by mass or more, preferably 60 parts by mass or more, relative to 100 parts by mass of the conductive material. When the proportion of the binder is equal to or more than the above lower limit, the strength of the first thermoelectric conversion member 3 can be ensured.

[0075] The proportion of the binder in the first thermoelectric conversion member 3 is, for example, 250 parts by mass or less, preferably 150 parts by mass or less, relative to 100 parts by mass of the conductive material. When the proportion of the binder is equal to or less than the above upper limit, the proportion of the conductive material is ensured, and the conductivity of the first thermoelectric conversion member 3 can be ensured.

[0076] (3) Second Thermoelectric Conversion Member At least a portion of the second thermoelectric conversion member 4 is disposed inside the resin body 2. The second thermoelectric conversion member 4 extends in the first direction. The second thermoelectric conversion member 4 is electrically connected to the first thermoelectric conversion member 3. In this embodiment, the second thermoelectric conversion member 4 is thread-shaped. The shape of the second thermoelectric conversion member 4 is not limited. The second thermoelectric conversion member 4 may be, for example, strip-shaped, needle-shaped, or rod-shaped.

[0077] The diameter of the second thermoelectric conversion member 4 is, for example, 150 μm or more, preferably 300 μm or more, and for example, 3000 μm or less, preferably 1500 μm or less, more preferably 1000 μm or less, similar to the first thermoelectric conversion member 3. When the diameter of the second thermoelectric conversion member 4 is equal to or greater than the above lower limit, the electromotive force of the second thermoelectric conversion member 4 can be increased.

[0078] The second thermoelectric conversion member 4 has a second electromotive portion 41. The second electromotive portion 41 is electrically connected to the first electromotive portion 31 of the first thermoelectric conversion member 3. One end of the second electromotive portion 41 is connected to the other end of the first electromotive portion 31. The other end of the second electromotive portion 41 is connected to the electrode 6. The electrical connection between the first electromotive portion 31 and the second electromotive portion 41 is not limited. For example, the second electromotive portion 41 may be joined to the first electromotive portion 31 of the first thermoelectric conversion member 3 via a conductive bonding material such as silver paste, copper paste, or solder. Alternatively, the first thermoelectric conversion member 3 and the second thermoelectric conversion member 4 may be a single continuous thermoelectric conversion member, and the second electromotive portion 41 may be continuous with the first electromotive portion 31. The entire second electromotive portion 41 is disposed inside the resin body 2. All of the second electromotive units 41 are disposed within one resin body 2 together with all of the first electromotive units 31. The second electromotive units 41 extend in a first direction. The second electromotive units 41 generate electromotive force due to a temperature difference in the first direction. The second electromotive units 41 have a predetermined length in the first direction.

[0079] The length of the second electromotive part 41 in the first direction is, for example, 10 mm or more, preferably 20 mm or more. When the length of the second electromotive part 41 in the first direction is equal to or greater than the above-mentioned lower limit, the electromotive force can be increased. The upper limit of the length of the second electromotive part 41 in the first direction is not limited. The length of the second electromotive part 41 in the first direction is, for example, 80 mm or less.

[0080] The second thermoelectric conversion member 4 is an N-type thermoelectric conversion member. The second thermoelectric conversion member 4 behaves as an N-type semiconductor. Since the first thermoelectric conversion member 3 behaves as a P-type semiconductor and the second thermoelectric conversion member 4 behaves as an N-type semiconductor, the first electromotive part 31 and the second electromotive part 41 are electrically connected to each other, and thereby the first electromotive part 31 and the second electromotive part 41 form one cell structure of a π-type thermoelectric conversion element. This makes it possible to increase the electromotive force.

[0081] More specifically, the second thermoelectric conversion member 4 contains a carbon material as a conductive material, an N-type dopant, and, if necessary, a binder.

[0082] The conductive material may be the same as the conductive material of the first thermoelectric conversion member 3 described above.

[0083] The proportion of the conductive material in the second thermoelectric conversion member 4 is, for example, 30 mass % or more, preferably 40 mass % or more, and more preferably 50 mass % or more. When the proportion of the conductive material is equal to or greater than the above lower limit, the conductivity of the second thermoelectric conversion member 4 can be ensured.

[0084] The proportion of the conductive material in the second thermoelectric conversion member 4 is, for example, 70 mass % or less, preferably 60 mass % or less. When the proportion of the conductive material is equal to or less than the above upper limit, the proportion of the binder can be secured, and the strength of the second thermoelectric conversion member 4 can be secured.

[0085] The proportion of the conductive material in the second thermoelectric conversion member 4 is, for example, 40 parts by mass or more, preferably 60 parts by mass or more, relative to 100 parts by mass of the binder. When the proportion of the conductive material is equal to or more than the above lower limit, the conductivity of the second thermoelectric conversion member 4 can be ensured.

[0086] The proportion of the conductive material in the second thermoelectric conversion member 4 is, for example, 250 parts by mass or less, preferably 150 parts by mass or less, relative to 100 parts by mass of the binder. When the proportion of the conductive material is equal to or less than the above upper limit, the proportion of the binder can be secured, and the strength of the second thermoelectric conversion member 4 can be secured.

[0087] The binder binds the conductive material together. Examples of the binder include the same binders as those used for the first thermoelectric conversion member 3 described above.

[0088] The proportion of the binder in the second thermoelectric conversion member 4 is, for example, 30 mass % or more, or preferably 40 mass % or more. When the proportion of the binder is equal to or more than the above lower limit, the tensile strength of the second thermoelectric conversion member 4 can be ensured.

[0089] The proportion of the binder in the second thermoelectric conversion member 4 is, for example, 70 mass % or less, preferably 60 mass % or less. When the proportion of the binder is equal to or less than the above upper limit, the proportion of the conductive material can be ensured, and the conductivity of the second thermoelectric conversion member 4 can be ensured.

[0090] The proportion of the binder in the second thermoelectric conversion member 4 is, for example, 40 parts by mass or more, preferably 60 parts by mass or more, relative to 100 parts by mass of the conductive material. When the proportion of the binder is equal to or more than the above lower limit, the strength of the second thermoelectric conversion member 4 can be ensured.

[0091] The proportion of the binder in the second thermoelectric conversion member 4 is, for example, 250 parts by mass or less, preferably 150 parts by mass or less, relative to 100 parts by mass of the conductive material. When the proportion of the binder is equal to or less than the above upper limit, the proportion of the conductive material is ensured, and the conductivity of the second thermoelectric conversion member 4 can be ensured.

[0092] The N-type dopant gives the electrical properties of an N-type semiconductor to the second thermoelectric conversion member 4. For example, 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM-PF ６), polyethyleneimine (PEI), ethylenediaminetetrakis(propoxylate-block-ethoxylate) tetrol (trade name: Tetronic® 1107), reduced benzyl viologen (reduced BV), diphenylphosphine (dpp), 1,2-bis(diphenylphosphino)ethane (dppe), 1,3-bis(diphenylphosphino)propane (dppp), 1,4-bis(diphenylphosphino)butane (dppb), bis(diphenylphosphinomethyl)phenylphosphine (dpmp), bis(diphenylphosphinoethyl)phenylphosphine (ppmdp), bis[(diphenylphosphinomethyl)phenylphosphino]methane (dpmpppm), triphenylphosphine (tpp), tris(p-fluorophenyl)phosphine (F-tpp), tris(p-chlorophenyl)phosphine (Cl-tpp), tris(p-methoxyphenyl)phosphine (P-methyl ... Examples of N-type dopants include tris(4-methoxy-3,5-dimethylphenyl)phosphine (MeO-tpp), tris(4-methoxy-3,5-dimethylphenyl)phosphine (tmdp), indole (Id), polyvinylpyrrole (PVPy), polyvinylpyrrolidone (PVP), 1,3-dimethyl-2-(o-methoxyphenyl)benzimidazole (o-MeO-DMBI), hydrazine monohydrate (HH), phenylhydrazine (MPH), 1,2-diphenylhydrazine (DPH), diazabicycloundecene (DBU), 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD), and 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene (MTBD). As the N-type dopant, triphenylphosphine is preferably used.

[0093] (4) Electrode The electrode 5 is disposed at one end of the resin body 2 in the first direction. At least a portion of the electrode 5 is disposed outside the resin body 2. The electrode 5 is electrically connected to the first thermoelectric conversion member 3. The electrode 5 is electrically connected to one end of the first electromotive part 31, for example, via a bonding material such as solder. In this embodiment, the electrode 5 is a lead wire made of metal.

[0094] The electrode 6 is arranged at one end of the resin body 2 in the first direction. The electrode 6 is arranged away from the electrode 5. At least a portion of the electrode 6 is arranged outside the resin body 2. The electrode 6 is electrically connected to the second thermoelectric conversion member 4. The electrode 6 is electrically connected to the other end of the second electromotive part 41, for example, via a bonding material such as solder. In this embodiment, the electrode 6 is a lead wire made of metal.

[0095] 2. Heat Insulating Structure for Pipe Next, a heat insulating structure for pipe 10 will be described as an example of a use of the thermoelectric conversion element 1. Note that the use of the thermoelectric conversion element 1 is not limited to the heat insulating structure for pipe 10.

[0096] As shown in FIG. 3 , the heat insulating structure 10 for piping includes a pipe 11 , a heat insulating material 12 , the thermoelectric conversion element 1 described above, an exterior member 13 , a second heat insulating material 14 , and a cover 15 .

[0097] (1) Heat Insulating Material The heat insulating material 12 covers the pipe 11. The heat insulating material 12 has a predetermined thickness. The heat insulating material 12 has one side S1 and another side S2 in the thickness direction of the heat insulating material 12. The other side S2 is disposed between the one side S1 and the pipe 11 in the thickness direction.

[0098] The heat insulating material 12 has heat insulating performance. The heat insulating performance of the heat insulating material 12 can be defined by the thermal conductivity of the heat insulating material 12.

[0099] The thermal conductivity of the heat insulating material 12 is, for example, 1 W / m K or less, preferably 0.5 W / m K or less. When the thermal conductivity of the heat insulating material 12 is equal to or less than the upper limit, a temperature difference in the thickness direction can be ensured, and the obtained electromotive force can be increased.

[0100] There is no lower limit for the thermal conductivity of the heat insulating material 12. The thermal conductivity of the heat insulating material 12 is, for example, 0.01 W / m·K or more.

[0101] Examples of materials for the heat insulating material 12 include glass wool, rock wool, calcium silicate, polystyrene, polyethylene, urethane resin, melamine resin, phenolic resin, foam glass, perlite, cellulose fiber, alumina fiber, ceramic fiber, carbon fiber, fumed silica, and alkaline earth silicate. Preferred materials for the heat insulating material 12 include glass wool, rock wool, and calcium silicate, and more preferred materials include glass wool.

[0102] The thickness of the heat insulating material 12 is, for example, 10 mm or more, preferably 30 mm or more. When the thickness of the heat insulating material 12 is equal to or more than the above lower limit, a temperature difference in the thickness direction can be ensured, and the obtained electromotive force can be increased.

[0103] There is no upper limit to the thickness of the heat insulating material 12. The thickness of the heat insulating material 12 is, for example, 300 mm or less.

[0104] When the insulating material 12 is made of glass wool or rock wool, the apparent density of the insulating material 12 is, for example, 200 kg / m ３ Preferably, 100 kg / m or less ３ The following is the result.

[0105] When the insulating material 12 is made of glass wool or rock wool, the apparent density of the insulating material 12 is, for example, 10 kg / m ３ More than 24 kg / m ３ When the apparent density of the heat insulating material 12 is equal to or greater than the above lower limit, a sufficient temperature difference can be ensured in the thickness direction.

[0106] When the thermal insulating material 12 is made of calcium silicate, the apparent density of the thermal insulating material 12 is, for example, 300 kg / m ３ Preferably, 150 kg / m or less ３ The following is the result.

[0107] When the insulating material 12 is made of calcium silicate, the apparent density of the insulating material 12 is, for example, 50 kg / m ３ When the apparent density of the heat insulating material 12 is equal to or greater than the above lower limit, a sufficient temperature difference can be ensured in the thickness direction.

[0108] The thermoelectric conversion element 1 is embedded in the thermal insulation material 12. More specifically, the thermal insulation material 12 has a hole 12A. The hole 12A extends in the thickness direction of the thermal insulation material 12. The hole 12A is recessed from one surface S1 of the thermal insulation material 12 toward the other surface S2. The hole 12A may penetrate the thermal insulation material 12. The thermoelectric conversion element 1 is embedded in the hole 12A. In other words, the thermoelectric conversion element 1 described above can be embedded in the thermal insulation material 12. With the thermoelectric conversion element 1 embedded in the thermal insulation material 12, the first electromotive part 31 and the second electromotive part 41 extend in the thickness direction of the thermal insulation material 12.

[0109] (2) Exterior Member The exterior member 13 covers the heat insulating material 12. The exterior member 13 is disposed on the opposite side of the heat insulating material 12 from the pipe 11 in the thickness direction of the heat insulating material 12. The exterior member 13 prevents the heat insulating material 12 from getting wet. The exterior member 13 is made of, for example, metal. The exterior member 13 has an opening 130. The thermoelectric conversion element 1 is disposed in the opening 130.

[0110] (3) Second Insulating Material The second insulating material 14 is disposed within the opening 130. The second insulating material 14 is disposed overlapping the insulating material 12. The second insulating material 14 covers the thermoelectric conversion element 1. The second insulating material 14 is disposed on the opposite side of the pipe 11 from the thermoelectric conversion element 1 in the thickness direction of the insulating material 12. The second insulating material 14 is made of, for example, the same material as the insulating material 12. The second insulating material 14 may be made of a different material from the insulating material 12.

[0111] (5) Cover The cover 15 closes the opening 130 of the exterior member 13. The cover 15 can open and close the opening 130. The cover 15 may be detachable from the exterior member 13. The cover 15 is made of, for example, the same material as the exterior member 13. The cover 15 may also be made of a different material from the exterior member 13.

[0112] 2 , the thermoelectric conversion element 1 includes a first thermoelectric conversion member 3 containing a carbon material as a conductive material, and an insulating resin body 2. The first electromotive portion 31 of the first thermoelectric conversion member 3 is disposed within the resin body 2.

[0113] Therefore, while the weight of the thermoelectric conversion element 1 can be reduced, for example, when the target of construction is an insulating material 12 covering a pipe 11, as shown in Figure 3, the first electromotive part 31 of the first thermoelectric conversion member 3 can be placed within the insulating material 12 by the simple process of drilling a hole 12A in the insulating material 12 and embedding the resin body 2 in the insulating material 12.

[0114] This allows the thermoelectric conversion element 1 to be easily attached to the heat insulating material 12 that covers the pipe 11.

[0115] (2) As shown in Fig. 2, the thermoelectric conversion element 1 further includes a thread-like second thermoelectric conversion member 4. The second thermoelectric conversion member 4 is an N-type thermoelectric conversion member and has a second electromotive part 41. The second electromotive part 41 is disposed inside the resin body 2 and is electrically connected to the first electromotive part 31.

[0116] Since the first thermoelectric conversion member 3 behaves as a P-type semiconductor and the second thermoelectric conversion member 4 behaves as an N-type semiconductor, the first electromotive part 31 and the second electromotive part 41 are electrically connected, and the first electromotive part 31 and the second electromotive part 41 form a single cell structure of a π-type thermoelectric conversion element.

[0117] As a result, the electromotive force can be increased.

[0118] (3) According to the heat insulation structure of the pipe 11, as shown in FIG. 3 , the first electromotive portion 31 of the first thermoelectric conversion member 3 and the second electromotive portion 41 of the second thermoelectric conversion member 4 can be arranged within the heat insulation material 12 by the simple process of drilling a hole 12A in the heat insulation material 12 covering the pipe 11 and embedding the resin body 2 of the thermoelectric conversion element 1 in the heat insulation material 12.

[0119] This allows the thermoelectric conversion element 1 to be easily attached to the heat insulating material 12 that covers the pipe 11.

[0120] (4) As shown in Fig. 3, the heat insulating structure of the pipe 11 includes a second heat insulating material 14. The second heat insulating material 14 is disposed on top of the heat insulating material 12 and covers the thermoelectric conversion element 1.

[0121] When the thermoelectric conversion element 1 is embedded in the heat insulating material 12, the heat insulating properties may be reduced in the portion where the thermoelectric conversion element 1 is embedded (i.e., the portion where the hole 12A is formed).

[0122] In this regard, by covering the thermoelectric conversion element 1 with the second heat insulating material 14, it is possible to compensate for the decrease in heat insulating properties.

[0123] (5) According to the heat insulating structure of the pipe 11, as shown in FIG. 3, the exterior member 13 covering the heat insulating material 12 has the opening 130, and the thermoelectric conversion element 1 is disposed in the opening 130.

[0124] Therefore, the thermoelectric conversion element 1 can be electrically connected to an external electronic device through the opening 130 of the exterior member 13 .

[0125] (6) According to the heat insulating structure of the pipe 11, as shown in FIG. 3, the cover 15 that closes the opening 130 of the exterior member 13 is provided.

[0126] Therefore, by closing the cover 15, the heat insulating material 12 inside the opening 130 can be prevented from getting wet.

[0127] 4. Modifications Modifications will be described below. In the modifications, the same components as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

[0128] (1) As shown in FIG. 4, the thermoelectric conversion element 1 may have a plurality of cell structures 100A and 100B each including a first electromotive portion 31 and a second electromotive portion 41.

[0129] The cell structure 100A and the cell structure 100B may be connected in series so that the first electromotive units 31 and the second electromotive units 41 are alternately connected to one another. Specifically, one end of the first electromotive unit 31 of the cell structure 100A is connected to the electrode 5. The other end of the first electromotive unit 31 of the cell structure 100A is connected to one end of the second electromotive unit 41 of the cell structure 100A. One end of the first electromotive unit 31 of the cell structure 100B is connected to the other end of the second electromotive unit 41 of the cell structure 100A. The other end of the first electromotive unit 31 of the cell structure 100B is connected to one end of the second electromotive unit 41 of the cell structure 100B. The other end of the second electromotive unit 41 of the cell structure 100B is connected to the electrode 6.

[0130] According to this modification, the electromotive force can be increased by using a plurality of cell structures 100A and 100B.

[0131] (2) As shown in Fig. 5 , the second electromotive part 41 may be covered with an insulating layer 200. In this case, the first electromotive part 31 may be in contact with the insulating layer 200. The insulating layer 200 is sealed together with the second electromotive part 41 within the resin body 2.

[0132] Resin, for example, can be used as the material of the insulating layer 200. Examples of the resin include epoxy resin, acrylic resin, urethane resin, fluororesin, polyvinyl alcohol, ethylene vinyl alcohol, polybutylene terephthalate, polyamide, polyimide, polyvinyl acetal, polysilsesquioxane, polysilazane, and parylene.

[0133] The thickness of the insulating layer 200 in the radial direction of the second electromotive part 41 is, for example, 2 μm or more, or preferably 10 μm or more, and for example, 1000 μm or less, or preferably 500 μm or less.

[0134] According to this modification, the first electromotive part 31 and the second electromotive part 41 can be arranged close to each other within the resin body 2 .

[0135] Therefore, the thermoelectric conversion element 1 can be made smaller.

[0136] (3) As shown in FIG. 6 , the resin element 2 may seal the joint 300 between the electrode 5 and the first electromotive part 31 and the joint 300 between the electrode 6 and the second electromotive part 41 .

[0137] According to this modification, the joint portion 300 can be protected by the resin body 2 .

[0138] (4) As shown in FIG. 7, the thermoelectric conversion element 1 may include a metal wire W instead of the second thermoelectric conversion member 4 .

[0139] The wire W is disposed inside the resin body 2. The wire W is electrically connected to the first electromotive part 31. More specifically, one end of the wire W is connected to the other end of the first electromotive part 31. The other end of the wire W is connected to the electrode 6.

[0140] 5, the wire W may be covered with an insulating layer 200. In this case, the first electromotive part 31 may be in contact with the insulating layer 200 covering the wire W. The insulating layer 200 covering the wire W may be the same as or different from the insulating layer 200 covering the second electromotive part 41.

[0141] (5) As shown in Fig. 8, the electrodes 5 and 6 are not limited to lead wires. The electrodes 5 and 6 may have a flat plate shape.

[0142] (6) As shown in Figure 9, the other end of the first electromotive part 31 may be located outside the resin body 2. In addition, one end of the second electromotive part 41 may also be located outside the resin body 2. The other end of the first electromotive part 31 and one end of the second electromotive part 41 may be electrically connected outside the resin body 2.

[0143] According to this modification, the other end of the first electromotive part 31 and one end of the second electromotive part 41 can be brought into contact with a heat source outside the resin body 2 .

[0144] Therefore, compared to when the other end of the first electromotive part 31 and one end of the second electromotive part 41 are positioned inside the resin body 2, the amount of power generation can be increased and the response speed can be improved.

[0145] (7) The same effects as those of the above-described embodiment can be obtained with the modifications (1) to (6). Note that the above-described inventions are provided as exemplary embodiments of the present invention, but these are merely examples and should not be interpreted as limiting. Modifications of the present invention that are obvious to those skilled in the art are included in the scope of the following claims.

[0146] The thermoelectric conversion element of the present invention can be used, for example, as a sensor or a power source. The heat insulating structure for piping of the present invention can be used for insulating piping.

[0147] REFERENCE SIGNS LIST 1 thermoelectric conversion element 2 resin body 3 first thermoelectric conversion member (thermoelectric conversion member) 31 first electromotive portion 4 second thermoelectric conversion member 41 second electromotive portion 5 electrode 6 electrode 10 heat insulating structure 11 piping 12 heat insulating material 13 exterior member 130 opening 14 second heat insulating material 15 cover 100A cell structure 100B cell structure 200 insulating layer W wire

Claims

1. A thermoelectric conversion element comprising: an insulating resin body extending in a first direction; and a thermoelectric conversion member containing a carbon material as a conductive material, wherein the thermoelectric conversion member is disposed inside the resin body, has a predetermined length in the first direction, and has an electromotive portion that generates an electromotive force in response to a temperature difference in the first direction.

2. The thermoelectric conversion element according to claim 1, further comprising an electrode disposed outside the resin body and electrically connected to the thermoelectric conversion member.

3. A thermoelectric conversion element according to claim 1, which can be embedded in a thermal insulating material, and in a state where the thermoelectric conversion element is embedded in the thermal insulating material, the electromotive portion extends in the thickness direction of the thermal insulating material.

4. The thermoelectric conversion element according to claim 1, wherein the thermoelectric conversion member is a P-type thermoelectric conversion member.

5. A thermoelectric conversion element as described in claim 4, further comprising a second thermoelectric conversion member containing a carbon material as a conductive material, wherein the second thermoelectric conversion member is an N-type thermoelectric conversion member, the second thermoelectric conversion member is disposed inside the resin body, has a predetermined length in the first direction, and has a second electromotive part that generates an electromotive force due to a temperature difference in the first direction, and the second electromotive part is electrically connected to the electromotive part.

6. The thermoelectric conversion element according to claim 5, having a structure of a plurality of cells each consisting of the electromotive portion and the second electromotive portion.

7. A thermoelectric conversion element according to claim 5, wherein the second electromotive portion is covered with an insulating layer, and the electromotive portion is in contact with the insulating layer.

8. The thermoelectric conversion element according to claim 1, further comprising a metal wire disposed inside the resin body and electrically connected to the electromotive portion.

9. The thermoelectric conversion element according to claim 8, wherein the wire is covered with an insulating layer, and the electromotive portion is in contact with the insulating layer.

10. A heat insulating structure for a pipe, comprising: a pipe; a heat insulating material covering the pipe; and a thermoelectric conversion element according to any one of claims 1 to 9 embedded in the heat insulating material.

11. The heat insulating structure for piping according to claim 10, further comprising a second heat insulating material disposed on top of the heat insulating material and covering the thermoelectric conversion element.

12. The heat-insulating structure for piping according to claim 11, further comprising an exterior member covering the heat-insulating material, the exterior member having an opening, and the thermoelectric conversion element being disposed within the opening.

13. The heat insulating structure for piping according to claim 12, further comprising a cover that closes the opening in the exterior member.

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