JP2013033810A - Thermoelectric conversion module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a risk occurring when a thermoelectric conversion module including a fin is used and handled.SOLUTION: A thermoelectric conversion module 10 comprises: a heat absorber 12; a thermoelectric conversion element 11 provided above the heat absorber 12 and thermally connecting with the heat absorber 12; a heat insulation body 14 provided at the outer side of the thermoelectric conversion element 11 above the heat absorber 12; and a radiator 13 provided above the thermoelectric conversion element 11 and thermally connecting with the thermoelectric conversion element 11. The radiator 13 includes a fin 13c having flexibility. Allowing the fin 13c to have the flexibility reduces a risk for injuries and the likes which occur when the thermoelectric conversion module 10 is used and handled.

Description

  The present invention relates to a thermoelectric conversion module that converts thermal energy into electrical energy.

  A thermoelectric conversion module having a structure including a thermoelectric conversion element between two heat conductors such as a thermoelectric conversion element that converts thermal energy into electric energy and a heat-insulated metal is known. In the thermoelectric conversion module, electric power is generated by giving a temperature difference between the two heat conductors and generating a potential difference in the thermoelectric conversion element by the Seebeck effect.

  In recent years, a thermoelectric conversion module is mounted on a wearable device, generating heat using the temperature difference between body temperature and outside air by absorbing the body temperature with one heat conductor and dissipating heat (cooling with outside air) with the other heat conductor. There is also known a technique for performing the above and using it for the power source of the device. In addition, a technique of providing a fin made of metal or the like protruding outward on the heat conductor on the heat radiation side is also known.

JP 2002-257916 A JP 2007-110082 A

“Journal of Electrocardiology”, 2007, Vol. 40, pp. S165-S168

  The fins provided on the heat dissipation side heat conductor of the thermoelectric conversion module can be said to be an effective technique for enhancing the heat generation efficiency, ensuring the temperature difference from the heat absorption side heat conductor, and increasing the power generation efficiency. However, in consideration of application of thermoelectric conversion modules to living bodies such as human bodies and animals, fins formed of relatively hard materials such as metals may hurt living bodies when using or handling thermoelectric conversion modules. It has sex.

  According to an aspect of the present invention, a first thermal conductor, at least one thermoelectric conversion element provided above the first thermal conductor and thermally connected to the first thermal conductor; A heat-insulating body provided outside the thermoelectric conversion element above the first thermal conductor, and a fin having a flexibility provided above the thermoelectric conversion element and thermally connected to the thermoelectric conversion element A thermoelectric conversion module comprising: a second heat conductor comprising:

  According to the disclosed thermoelectric conversion module, it is possible to suppress the damage of the living body caused by the fins and increase the safety during use and handling by providing the fins with flexibility.

It is a figure which shows an example of the thermoelectric conversion module which concerns on 1st Embodiment. It is a figure which shows an example of the thermoelectric conversion element mounted in the thermoelectric conversion module which concerns on 1st Embodiment. It is a figure which shows the example of the heat radiator of the thermoelectric conversion module which concerns on 1st Embodiment. It is a figure (the 1) which shows an example of the thermoelectric conversion module which concerns on 2nd Embodiment. It is a figure (the 2) which shows an example of the thermoelectric conversion module which concerns on 2nd Embodiment. It is FIG. (3) which shows an example of the thermoelectric conversion module which concerns on 2nd Embodiment. It is a figure which shows an example of the formation method of the fin which concerns on 2nd Embodiment. It is a figure which shows an example of the thermoelectric conversion module of another form. It is a figure which shows another example of the thermoelectric conversion module which concerns on 2nd Embodiment. It is a figure which shows an example of the thermoelectric conversion module which concerns on 3rd Embodiment. It is a figure which shows an example of the formation method of the fin which concerns on 3rd Embodiment. It is a figure which shows another example of the formation method of the fin which concerns on 3rd Embodiment. It is a figure which shows another example of the thermoelectric conversion module which concerns on 3rd Embodiment.

First, the first embodiment will be described.
FIG. 1 is a diagram illustrating an example of a thermoelectric conversion module according to the first embodiment, and FIG. 2 is a diagram illustrating an example of a thermoelectric conversion element mounted on the thermoelectric conversion module according to the first embodiment. 1 is a schematic cross-sectional view of an essential part of an example of a thermoelectric conversion module, and FIG. 2 is a schematic perspective view of an essential part of an example of a thermoelectric conversion element.

  As shown in FIG. 1A, a thermoelectric conversion module 10 includes a thermoelectric conversion element 11, a heat-absorbing-side heat conductor (heat-absorbing body) 12 that absorbs heat from a heat source, and a heat-radiating-side heat conduction that dissipates heat to the outside. It has a body (heat radiator) 13 and a heat insulator 14.

  The thermoelectric conversion element 11 has a structure in which a plurality of semiconductor blocks 11c using a thermoelectric conversion material are sandwiched between a pair of opposing substrates (heat transfer bodies) 11a and 11b. As the semiconductor block 11c, a plurality of semiconductor blocks (p-type semiconductor blocks) 11p using a p-type thermoelectric conversion material and a plurality of semiconductor blocks (n-type semiconductor blocks) 11n using an n-type thermoelectric conversion material are used.

  The p-type semiconductor block 11p and the n-type semiconductor block 11n are alternately arranged in the in-plane direction of the heat transfer body 11a as shown in FIG. 2 (for the sake of convenience, illustration of one heat transfer body 11b is omitted) They are connected in series using a terminal 11d made of metal or the like. A lead electrode 11e is connected to the terminal p-type semiconductor block 11p and n-type semiconductor block 11n connected in series in this way.

  That is, the thermoelectric conversion element 11 shown in FIG. 2 is a so-called π-type thermoelectric conversion element in which a pair of p-type semiconductor block 11p and n-type semiconductor block 11n, and a terminal 11d that electrically connects them are arranged in π-type. It is.

  In the thermoelectric conversion element 11, when a temperature difference is given to the heat transfer bodies 11a and 11b, a potential difference is generated in each of the p-type semiconductor block 11p and the n-type semiconductor block 11n due to the Seebeck effect, and the lead electrode 11e Electric power is taken out.

  The number and arrangement of the p-type semiconductor block 11p and the n-type semiconductor block 11n, the terminal 11d, and the extraction electrode 11e shown in FIG. 2 are examples, and the configuration of the thermoelectric conversion element 11 is shown in FIG. The configuration is not limited. Although a π-type thermoelectric conversion element will be described as an example of the thermoelectric conversion element 11, a thermoelectric conversion element having another configuration such as a planar thermoelectric conversion element may be used.

  This will be further described with reference to FIG. The heat transfer bodies 11a and 11b of the thermoelectric conversion element 11 are thermally connected to the heat absorbing body 12 and the heat radiating body 13, respectively. A heat insulator 14 such as a foamed resin having flexibility is provided on the side of the thermoelectric conversion element 11, and the heat insulation effect between the heat absorber 12 and the heat radiator 13 is enhanced by the heat insulator 14. Yes.

  The thermoelectric conversion module 10 is arranged with the heat absorbing body 12 of the heat absorbing body 12 and the heat radiating body 13 facing the heat source when used. When the heat absorber 12 absorbs the heat of the heat source, the heat transfer element 11a side of the thermoelectric conversion element 11 that is thermally connected to the heat absorber 12 is warmed, and is thermally connected to the heat radiator 13 that is in contact with the outside air. A temperature difference is generated between the thermoelectric conversion element 11 and the heat transfer body 11b. Due to this temperature difference, power generation as described above is performed. The heat dissipating body 13 is provided with a plurality of fins 13c in order to increase the surface area thereof to increase heat dissipating (cooling) efficiency and to generate a predetermined temperature difference required for power generation between the heat transmitting bodies 11a and 11b.

  In the thermoelectric conversion module 10, the heat dissipating body 13 provided with such fins 13c has a high thermal conductivity equal to or higher than that of a metal lump such as copper (Cu) or aluminum (Al), and Cu or Al. It is formed using a material having flexibility that can be deformed more flexibly than a metal lump. For example, the heat radiator 13 is formed using a sheet material having such thermal conductivity and flexibility.

FIG. 3 is a diagram illustrating an example of a heat radiator of the thermoelectric conversion module according to the first embodiment. FIG. 3 is a schematic cross-sectional view of an essential part of an example of the heat radiator.
For example, as shown in FIG. 3A, a plurality of sheets (here, three sheets as an example) are overlapped with an adhesive layer 13b, and the upper layer sheet 13a is partially folded back. The folded portion is used as the fin 13c. Note that FIGS. 3B and 3C will be described later.

Examples of the sheet material that can be used for the heat radiator 13 include a graphite sheet.
The graphite sheet has a thin and light property. Therefore, the use of the graphite sheet contributes to the miniaturization and weight reduction of the thermoelectric conversion module 10, which is one of the advantages when the thermoelectric conversion module 10 is applied to a living body such as a human body.

Furthermore, the graphite sheet has a high thermal conductivity in the in-plane direction and has a low thermal resistance even if it is thin. In the case of the human body, the amount of generated heat is about 6 mW / cm ² , which is small compared to heat-generating electronic devices that require fins, and the heat transfer coefficient of the skin is also small, 18.5 W / m ² K. . If it is a graphite sheet, even if it is a heat source with a comparatively small generated heat quantity like a human body, the heat dissipation effect exceeding a metal heat conductor and a fin can be acquired.

  Furthermore, the graphite sheet has flexibility. When such a flexible material such as a graphite sheet is used, when the thermoelectric conversion module 10 is applied to a living body such as a human body, the object 100 such as a body is placed on the fin 13c as shown in FIG. Even if it collides, the fin 13c deform | transforms flexibly according to the collision. Therefore, the risk of injury and damage can be reduced.

  A material having high thermal conductivity and flexibility such as a graphite sheet can be used for the heat absorber 12 in addition to the heat radiator 13. For example, as in FIG. 3A, a plurality of sheet materials such as a graphite sheet having high thermal conductivity and flexibility are overlapped with each other through an adhesive layer to form the heat absorber 12. By using such a material such as a graphite sheet for the heat absorber 12, heat absorption efficiency from a heat source such as a human body can be increased due to the high thermal conductivity of the material, and a predetermined temperature difference from the heat radiator 13 side. Can be secured. Further, the heat absorbing body 12 can be deformed along the shape of the heat source such as the human body together with the heat radiating body 13 and the heat insulating body 14 due to the flexibility of the material, and is in contact with or close to the heat source. The heat absorption efficiency from the heat source can be increased.

  Thus, by using a material having high thermal conductivity and flexibility such as a graphite sheet for the heat radiating body 13 and the heat absorbing body 12, the thermoelectric conversion module 10 having high power generation efficiency and less risk of damage at the fins 13c is obtained. be able to. Moreover, while using the material which has such high heat conductivity and a softness | flexibility for the heat radiator 13 and the heat absorber 12, the lightweight and flexible material like foamed resin (foamed polyolefin etc.) is used for the heat insulating body 14. FIG. If it uses, the thermoelectric conversion module 10 whole can be made lightweight and flexible. According to such a thermoelectric conversion module 10, even when worn on a human body or the like, it can be worn by being deformed in accordance with the shape of a worn part such as a human body, such as wrapping around an arm. It also becomes possible to reduce a sense of incongruity.

  The thermoelectric conversion module can be used, for example, as a power source for a wearable electronic device attached to a human body or the like in addition to a power source for wireless sensor nodes constituting a sensor network and various electronic devices that operate with relatively low power. When a metal is used for a heat transfer portion such as a heat conductor or fins of the thermoelectric conversion module, the thermoelectric conversion module becomes hard and heavy, and therefore, when it is attached to a human body or the like, there is a case where a feeling of strangeness at the time of attachment becomes large. In addition, the hard metal fins may hurt human bodies or the like when the thermoelectric conversion module is used or handled.

  On the other hand, in the thermoelectric conversion module 10 as shown in FIG. 1 above, by using a lightweight and flexible material such as a graphite sheet for the heat dissipating body 13 and the fins 13c provided on the heat dissipating body 13, damage due to the fins 13c of the human body or the like is caused. Risk can be reduced. Further, by using a lightweight and flexible material such as a graphite sheet or a foamed resin for the heat absorbing body 12 and the heat insulating body 14, respectively, it is possible to reduce a sense of incongruity when mounted on a human body or the like. Thereby, the thermoelectric conversion module 10 suitable for use which uses a human body etc. as a heat source is realizable.

Of course, the thermoelectric conversion module 10 as described above is not limited to use in which a living body such as a human body is used as a heat source, but can be used in which various electronic devices are used as a heat source.
Further, when the thermoelectric conversion module 10 is formed flexibly as a whole by selecting the material of each part as described above, the thermoelectric conversion module 10 can be mounted according to its shape regardless of whether the heat source is a living body or an electronic device. Is possible. However, even if the thermoelectric conversion module 10 is formed flexibly as a whole as described above, it can of course be mounted and used on a living body or an electronic device in a flat form as shown in FIG. It is.

  Further, in the thermoelectric conversion module 10, if at least the fins 13 c of the radiator 13 are formed using a flexible material, it is possible to suppress damage to the living body during use and handling of the thermoelectric conversion module 10. Is possible. For example, in addition to the form shown in FIG. 3A, the heat radiator 13 has a sheet material 13a having fins 13c as the folded portion on the surface of a flat metal base 13d as shown in FIG. 3B. It is also possible to adopt a form in which is adhered with an adhesive layer 13b. Further, as shown in FIG. 3C, the metal base 13d provided with the fin attachment portion 13da on the surface has the folded sheet material 13a adhered to the fin attachment portion 13da with the adhesive layer 13b. Is also possible.

  In addition, when the thermoelectric conversion module 10 is applied to a living body such as a human body, as shown in FIG. 1, the heat absorbing body 12 (the surface opposite to the thermoelectric conversion element 11 and facing the living body). Alternatively, a resin layer 16 containing a resin, fiber, or the like may be provided. By providing such a resin layer 16, it is possible to enhance the feeling of wearing when worn on a living body. As the material for the resin layer 16, for example, a silicone polymer having excellent biocompatibility can be used. In addition, fluorine-based, collagen-based, gelatin-based, catechin-based polymers, and the like can also be used.

Hereinafter, embodiments of the thermoelectric conversion module will be further described.
First, a second embodiment will be described.
4-6 is a figure which shows an example of the thermoelectric conversion module which concerns on 2nd Embodiment. 4 to 6 schematically show a cross section of an essential part of an example of the thermoelectric conversion module. 5 is an enlarged view of a portion X in FIG. 4, and FIG. 6 is an enlarged view of a portion Y in FIG.

  For example, as shown in FIG. 4, the thermoelectric conversion module 20 according to the second embodiment is mounted and used so as to be wound around a human arm 110. The thermoelectric conversion module 20 includes a thermoelectric conversion element 11, a heat absorber 22, a heat radiator 23, and a heat insulator 24.

  For example, the thermoelectric conversion element 11 as shown in FIG. 2 is used for the thermoelectric conversion module 20. The thermoelectric conversion element 11 includes, for example, a semiconductor block 11c (p-type semiconductor block 11p and n-type semiconductor block 11n) using a bismuth tellurium (BiTe) -based thermoelectric semiconductor as a thermoelectric conversion material, and a heat transfer body 11a made of alumina. It can be a π-type structure sandwiched between 11b. The dimensions of the thermoelectric conversion element 11 can be, for example, length (width) 5 mm × width (length) 5 mm × thickness 2 mm.

  The heat absorber 22 is thermally connected to one surface side of the thermoelectric conversion element 11, and the heat radiator 23 including the fins 23 c is heated on the other surface side of the thermoelectric conversion element 11 via the heat transfer block 25. Connected. A heat insulator 24 is provided between the heat absorber 22 and the heat radiator 23.

  A graphite sheet is used for the heat absorber 22 as a material having high thermal conductivity and flexibility. As the heat absorber 22, for example, as shown in FIG. 5, a sheet in which three sheets of graphite sheets 22a are overlapped via an adhesive layer 22b is used. As each graphite sheet 22a, for example, a sheet having a length (width) of 30 mm × width (length) of 150 mm × thickness of 70 μm can be used. Each adhesive layer 22b can have a thickness of 10 μm, for example. The thermoelectric conversion element 11 is bonded onto the heat absorber 22 via an adhesive layer.

  The heat insulator 24 provided on the heat absorber 22 so as to surround the thermoelectric conversion element 11 is made of a material having flexibility and low thermal conductivity. For the heat insulator 24, for example, foamed polyolefin is used. The thickness of the heat insulator 24 can be set to 6 mm, for example. As shown in FIG. 5, the heat insulator 24 (and the thermoelectric conversion element 11) is bonded onto the heat absorber 22 via an adhesive layer 22 d.

  For example, a Cu block can be used for the heat transfer block 25 provided on the thermoelectric conversion element 11. The dimensions of the heat transfer block 25 can be, for example, 5 mm in length (width) × 5 mm in width (length) × 4 mm in thickness. The heat transfer block 25 is bonded onto the thermoelectric conversion element 11 via an adhesive layer.

  For the radiator 23, a graphite sheet is used as a material having high thermal conductivity and flexibility. For example, as shown in FIG. 6, two sheets of graphite sheets 23a are stacked on the heat radiating body 23 via an adhesive layer 23b, and further, a graphite sheet 23a having a plurality of folded portions is provided on the heat sink 23b via the adhesive layer 23b. Adhered to each other. The heat radiator 23 is bonded onto the heat insulator 24 (and the heat transfer block 25) via an adhesive layer 23d.

  Each of the adhesive layers 23b and 23d can have a thickness of 10 μm, for example. For the two lower and middle graphite sheets 23a laminated from the heat insulator 24 side, for example, those having a length (width) of 30 mm × width (length) of 150 mm × thickness of 70 μm can be used. As the upper graphite sheet 23a including a plurality of folded portions, for example, one having a thickness of 70 μm can be used. For example, a plurality of folded portions having a height of 10 mm are provided in the upper graphite sheet 23a at intervals of 5 mm. In the second embodiment, the folded portion thus provided becomes the fins 23c of the heat radiating body 23.

FIG. 7 shows an example of a method for forming fins (folded portions) according to the second embodiment.
When forming the fins 23c, first, as shown in FIG. 7A, a sheet having an adhesive layer 23b formed on one surface of a graphite sheet 23a is prepared, and a part thereof is attached to a predetermined base layer 23e.

  After a part of the graphite sheet 23a on which the adhesive layer 23b is formed as shown in FIG. 7 (A) is pasted to the base layer 23e, the non-pasted part has a predetermined length of 1 as shown in FIG. 7 (B). One turn portion is formed. This folded portion becomes one fin 23c. In this way, for example, the fins 23c having a height of 10 mm as described above are formed.

  After one fin 23c is formed as shown in FIG. 7B, the graphite sheet 23a on which the adhesive layer 23b is formed is moved from the position of the first fin 23c to a predetermined value as shown in FIG. 7C. The length is pasted on the base layer 23e. Similarly to the above, the non-sticking portion of the graphite sheet 23a on which the adhesive layer 23b is formed is folded once by a predetermined length to form the second folded portion, that is, the second fin 23c. In this manner, for example, the second fin 23c having a distance of 5 mm from the first fin 23c and a height of 10 mm is formed.

  Thereafter, such a procedure is repeated, and the third and fourth fins 23c are similarly formed as shown in FIGS. 7D and 7E, and a predetermined number as shown in FIG. The graphite sheet 23a in which the fins 23c are formed is obtained.

  When forming the heat dissipating body 23 as shown in FIG. 6, for example, two graphite sheets 23a of a lower layer and an intermediate layer are overlapped via an adhesive layer 23b, and fins 23c are formed thereon as shown in FIG. The upper graphite sheet 23a is bonded with the adhesive layer 23b. In this case, the base layer 23e shown in FIG. 7 is an intermediate graphite sheet 23a.

  In addition, a separately prepared heat transfer sheet can be used for the base layer 23e. In this case, the upper graphite sheet 23a is bonded with the adhesive layer 23b while forming the fins 23c on the heat transfer sheet as shown in FIG. 7, and this is adhered to the intermediate graphite sheet 23a together with the heat transfer sheet. . Alternatively, after selectively removing the heat transfer sheet, the graphite sheet 23a on which the fins 23c are formed is attached to the intermediate graphite sheet 23a.

Alternatively, a metal base can be used for the base layer 23e.
When the thermoelectric conversion module 20 is not used, the thermoelectric conversion module 20 can maintain a flat shape like the thermoelectric conversion module 10 shown in FIG. Since the thermoelectric conversion module 20 uses a flexible material for the heat absorber 22, the heat radiator 23 (including the fins 23 c), and the heat insulator 24, it can be used such as being wrapped around the arm 110 as shown in FIG. 4. It has become. When the thermoelectric conversion module 20 is wound around the arm 110 and used in this manner, the thermoelectric conversion element 11 has a temperature difference between the heat absorber 22 side where heat from the arm 110 is transmitted and the heat radiator 23 side which is exposed to the outside air. A potential difference corresponding to that occurs, and power generation is performed.

  As an example, when the thermoelectric conversion module 20 to which the above-exemplified materials and dimensions were applied was produced, it was wrapped around the subject's arm, and the output of the thermoelectric conversion module 20 was examined in a room temperature of 26 ° C., no wind, at rest, An output of 207 μW was obtained.

  For comparison, a thermoelectric conversion module 1000 as shown in FIG. 8 was produced, and the output was examined under the same conditions. The thermoelectric conversion module 1000 shown in FIG. 8 uses the same thermoelectric conversion module 20 as the thermoelectric conversion element 11, the heat absorbing body 22, the heat insulating body 24, and the heat transfer block 25 except for the heat radiating body 1010. The radiator 1010 has a structure in which a plurality of Al fins 1012 having a diameter of 5 mm and a height of 20 mm are mounted on an aluminum (Al) metal base 1011 having a length (width) of 30 mm × width (length) of 50 mm. Used. Similar to the above, such a thermoelectric conversion module 1000 was wound around the arm of the subject, and when the output of the thermoelectric conversion module 1000 was examined in a room temperature of 26 ° C., no wind, and stationary, the output was 129 μW.

  As described above, the thermoelectric conversion module 20 can exhibit higher power generation capability even when attached to a human body than the thermoelectric conversion module 1000 having the heat radiating body 1010 provided with the metal fins 1012. Further, in the thermoelectric conversion module 20, since the fins 23c of the heat radiating body 23 can be flexibly deformed, the risk of damage is lower when compared with the thermoelectric conversion module 1000 provided with the metal fins 1012 even when attached to a human body. Can be reduced.

  As described above, according to the thermoelectric conversion module 20 according to the second embodiment, graphite sheets having high thermal conductivity and flexibility are used for the heat absorber 22 and the heat radiator 23. Thereby, the thermoelectric conversion module 20 with high power generation efficiency and less risk of damage at the fins 23c can be obtained.

  Moreover, while using a graphite sheet for the heat absorber 22 and the heat radiator 23 and using a lightweight and flexible material such as foamed polyolefin for the heat insulator 24, the thermoelectric conversion module 20 as a whole can be made lightweight and flexible. . As a result, it is possible to reduce the uncomfortable feeling at the time of wearing and wearing according to the shape of the heat source such as the human body.

  Further, in the thermoelectric conversion module 20 according to the second embodiment, from the viewpoint of improving the wearing feeling, the heat absorbing body 22 is provided on the surface that faces the living body such as the arm 110 and the like. A resin layer using a silicone-based polymer or the like as described in the embodiment may be provided.

Of course, the thermoelectric conversion module 20 as described above is not limited to use in which a human body or the like is used as a heat source, but can be used in which various electronic devices are used as a heat source.
Moreover, since the thermoelectric conversion module 20 having the above configuration has a flexible structure as a whole, the thermoelectric conversion module 20 can be mounted by being deformed according to its shape regardless of whether the heat source is a living body or an electronic device. However, even the thermoelectric conversion module 20 that is flexible as a whole can be used by being mounted on a living body or an electronic device in a flat form without being deformed. When the thermoelectric conversion module 20 is used in a flat form as described above, according to the example of FIGS. 3B and 3C, at least the fins 23c of the heat dissipating body 23 should have a flexible form. In addition, damage to the living body during use and handling of the thermoelectric conversion module 20 can be suppressed.

  Moreover, although the case where one thermoelectric conversion element 11 is provided in one thermoelectric conversion module 20 is illustrated here, it is also possible to provide a plurality of thermoelectric conversion elements 11 in one thermoelectric conversion module 20.

FIG. 9 is a diagram illustrating another example of the thermoelectric conversion module according to the second embodiment.
In the thermoelectric conversion module 20, for example, as shown in FIG. 9, a plurality (here, three as an example) of thermoelectric conversion elements 11 and heat transfer blocks 25 thermally connected thereto are arranged apart from each other. You can also. When providing the several thermoelectric conversion element 11, they can be electrically connected in series or can be connected in parallel.

  In the case where a plurality of thermoelectric conversion elements 11 are provided, if they are arranged apart from each other, the temperature of the heat-dissipation side heat transfer body 11b of each thermoelectric conversion element 11 can be reduced more efficiently than if they are arranged in a concentrated manner. Therefore, the power generation efficiency can be further increased. However, it is also possible to arrange a plurality of thermoelectric conversion elements 11 in an overlapping manner or adjacent to each other.

Next, a third embodiment will be described.
FIG. 10 is a diagram illustrating an example of a thermoelectric conversion module according to the third embodiment. In addition, in FIG. 10, the principal part cross section of an example of a thermoelectric conversion module is typically shown.

  The thermoelectric conversion module 30 according to the third embodiment is mounted and used so as to be wound around a human arm 110 as shown in FIG. 10, for example. The thermoelectric conversion module 30 includes a thermoelectric conversion element 11, a heat absorber 32, a heat radiator 33, and a heat insulator 34.

  As in the second embodiment, the thermoelectric conversion element 11 includes a semiconductor block 11c (a p-type semiconductor block 11p and an n-type semiconductor block 11n) using a BiTe-based thermoelectric semiconductor, and heat transfer bodies 11a and 11b made of alumina. A π-type structure sandwiched between can be used. The dimensions of the thermoelectric conversion element 11 can be, for example, length (width) 5 mm × width (length) 5 mm × thickness 2 mm.

  The heat absorber 32 is thermally connected to one surface side of the thermoelectric conversion element 11, and the heat radiator 33 including the fins 33 c is heated on the other surface side of the thermoelectric conversion element 11 via the heat transfer block 35. Connected. A heat insulator 34 is provided on the heat absorber 22 so as to surround the thermoelectric conversion element 11.

  As the heat absorber 32, a graphite sheet is used as a material having high thermal conductivity and flexibility. As the heat absorber 32, for example, as in FIG. 5, a sheet in which five graphite sheets are stacked with an adhesive layer interposed therebetween is used. As each graphite sheet, for example, a sheet having a length (width) of 30 mm × width (length) of 150 mm × thickness of 40 μm can be used. Each adhesive layer can have a thickness of 10 μm, for example. The thermoelectric conversion element 11 is bonded onto the heat absorber 32 via an adhesive layer.

  A material having flexibility and low thermal conductivity is used for the heat insulator 34. For the heat insulator 34, for example, foamed polyolefin is used. The thickness of the heat insulator 34 can be 6 mm, for example. The heat insulator 34 is bonded to the heat absorber 32 together with the thermoelectric conversion element 11 via an adhesive layer.

  For the heat transfer block 35, for example, a Cu block of 5 mm in length (width) x 5 mm in width (length) x 4 mm in thickness can be used. The heat transfer block 35 is bonded onto the thermoelectric conversion element 11 via an adhesive layer.

  The heat radiating body 33 is bonded onto the heat transfer block 25 via an adhesive layer. For the radiator 33, a graphite sheet is used as a material having high thermal conductivity and flexibility. As the heat radiating body 33, for example, a central part of four graphite sheets is bonded with an adhesive layer and a non-bonded part is radially expanded. In the third embodiment, these non-adhesive portions (radial portions) that are spread radially serve as fins 33c of the radiator 33. As each graphite sheet, for example, a sheet having a length (width) of 30 mm and a thickness of 70 μm can be used. The fin 33c can be about 50 mm to 20 mm in length.

An example of a method of forming fins (radial portions) according to the third embodiment is shown in FIG.
First, as shown in FIG. 11A, the fin 33c is formed by adhering the central portion of the first graphite sheet 33a on the heat transfer block 35 via the adhesive layer 33d.

  Similarly, as shown in FIGS. 11B to 11D, the center portions of the second to fourth graphite sheets 33a are sequentially laminated via the adhesive layer 33b. As shown in FIG. 11 (E), the heat dissipating body 33 provided with fins 33c radiating from the center as shown in FIG. 11 (E) is obtained by radially spreading the non-bonded portions of the four graphite sheets 33a laminated in this manner. It is formed on the heat transfer block 35.

  When the thermoelectric conversion module 30 is not used, the heat absorbing body 32 and the heat insulating body 34 are held in a flat form. Since the heat-absorbing body 32 and the heat insulator 34 are made of a flexible material, the heat-absorbing body 32 and the heat insulator 34 can be used such as being wrapped around the arm 110 as shown in FIG. When the thermoelectric conversion module 30 is wound around the arm 110 and used in this manner, the thermoelectric conversion element 11 has a temperature difference between the heat absorber 32 side where heat from the arm 110 is transmitted and the heat radiator 33 side exposed to the outside air. A potential difference corresponding to that occurs, and power generation is performed.

  As an example, when the thermoelectric conversion module 30 to which the above-exemplified materials and dimensions are applied is produced, it is wrapped around the subject's arm, and the output of the thermoelectric conversion module 30 is examined in a room temperature of 26 ° C., no wind, at rest. An output of 263 μW was obtained.

  In addition, as the heat radiating body 33 of the thermoelectric conversion module 30 shown in FIG. 10, in addition to the one formed by the method shown in FIG. 11, the one formed by the method shown in FIG. You can also.

FIG. 12 is a diagram showing another example of the fin forming method according to the third embodiment.
As another method for forming the fins 33c of the heat radiating body 33, first, as shown in FIG. 12A, a heat transfer block 35 having four fin mounting portions 35a radially provided on one side is prepared. Furthermore, as shown in FIG. 12 (B), a sheet having an adhesive layer 33b formed on one surface of a graphite sheet 33a is prepared, and folded and folded in two, leaving the end portion 33aa. Then, as shown in FIG. 12B and FIG. 12C, the end 33aa that remains without being bonded is sandwiched by one fin mounting portion 35a of the heat transfer block 35, and the fin mounting portion Adhere to 35a. The graphite sheet 33 a bonded to the fin attachment portion 35 a in this way becomes one fin 33 c of the heat radiating body 33.

  Similarly, the graphite sheet 33a adhered with the folded adhesive layer 33b is adhered to the other fin attachment portion 35a while leaving the end portion 33aa. Thereby, as shown in FIG. 12 (D), it is possible to obtain the heat dissipating body 33 in which the graphite sheets 33a to be the fins 33c are provided radially spreading from the central portion (heat transfer block 35).

  Here, the graphite sheet 33a folded only once is bonded to each fin mounting portion 35a. In addition to this, for example, the graphite sheet 33a in which one or a plurality of folded portions is formed in advance according to the example of FIG. 7 is bonded back by folding it once leaving the end portion 33aa, and this is bonded to each fin mounting portion 35a. You may do it. That is, a plurality of fins are further provided on each fin 33c. According to such a method, the surface area of the radiator 33 can be further increased.

  As described above, according to the thermoelectric conversion module 30 according to the third embodiment, graphite sheets having high thermal conductivity and flexibility are used for the heat absorber 32 and the heat radiator 33. Thereby, the thermoelectric conversion module 30 with high power generation efficiency and less risk of damage at the fins 33c can be obtained.

  Moreover, while using a graphite sheet for the heat absorber 32 and the heat radiator 33 and using a lightweight and flexible material such as foamed polyolefin for the heat insulator 34, the entire thermoelectric conversion module 30 can be made light and flexible. . As a result, it is possible to reduce the uncomfortable feeling at the time of wearing and wearing according to the shape of the heat source such as the human body.

  In addition, in the thermoelectric conversion module 30 according to the third embodiment, from the viewpoint of improving the wearing feeling, the heat absorption body 32 has a surface facing the living body, such as the arm 110, on the surface of the first embodiment. A resin layer using a silicone-based polymer or the like as described in the embodiment may be provided.

Of course, the thermoelectric conversion module 30 as described above is not limited to use in which a human body or the like is used as a heat source, but can be used in which various electronic devices are used as a heat source.
Moreover, since the thermoelectric conversion module 30 having the above configuration has a flexible structure as a whole, the thermoelectric conversion module 30 can be mounted by being deformed according to its shape regardless of whether the heat source is a living body or an electronic device. However, even the thermoelectric conversion module 30 that is flexible as a whole as described above can be used by being mounted on a living body or an electronic device in a flat form without being deformed.

  Moreover, although the case where one thermoelectric conversion element 11 is provided in one thermoelectric conversion module 30 is illustrated here, a plurality of thermoelectric conversion elements 11 can be provided in one thermoelectric conversion module 30.

FIG. 13 is a diagram illustrating another example of the thermoelectric conversion module according to the third embodiment.
In the thermoelectric conversion module 30, as shown in FIG. 13, for example, a plurality (here, three as an example) of thermoelectric conversion elements 11 can be arranged apart from each other. The heat radiating body 33 is thermally connected to the thermoelectric conversion elements 11 that are arranged apart from each other. When providing the several thermoelectric conversion element 11, they can be electrically connected in series or can be connected in parallel.

  In the case where a plurality of thermoelectric conversion elements 11 are provided, if they are arranged apart from each other, the temperature of the heat-dissipation side heat transfer body 11b of each thermoelectric conversion element 11 can be reduced more efficiently than if they are arranged in a concentrated manner. Therefore, the power generation efficiency can be further increased. However, it is also possible to arrange a plurality of thermoelectric conversion elements 11 in an overlapping manner or adjacent to each other.

The thermoelectric conversion modules 10, 20, and 30 have been described above.
In addition, as the graphite sheet becomes thicker, the thermal conductivity in the in-plane direction tends to decrease. Therefore, it is preferable to use the heat absorbing bodies 12, 22, 32 and the heat radiating bodies 13, 23, 33 of the thermoelectric conversion modules 10, 20, 30 having a form in which a plurality of thin graphite sheets are laminated as described above. . Thereby, high thermal conductivity can be ensured in the in-plane directions of the heat absorbers 12, 22, 32 and the heat radiators 13, 23, 33. In consideration of the application of the thermoelectric conversion modules 10, 20, and 30 to the human body, the amount of heat generated from the human body is relatively small on the heat absorption side, and the heat radiation side is cooled by blowing with a fan. Otherwise, it is preferable from the viewpoint that the heat transfer coefficient on the heat radiation side is also small.

  In the above description, the graphite sheet is exemplified as the sheet material used for the heat absorbing bodies 12, 22, 32 and the heat radiating bodies 13, 23, 33. However, if the sheet material has high thermal conductivity and flexibility, graphite can be used. It is also possible to use a sheet material other than the sheet. For example, it can replace with a graphite sheet and can also use metal foil, such as Al foil and Cu foil. The heat absorbers 12, 22, 32 and the heat radiators 13, 23, 33 can also be formed by laminating such metal foils using, for example, an adhesive layer according to the above example.

Note that the number of sheet materials such as graphite sheets applicable to the heat absorbers 12, 22, 32 and the heat radiators 13, 23, 33 is not limited to the above example.
In the above description, foamed polyolefin is cited as an example of the heat insulators 14, 24, 34. In addition, foamed resins such as foamed polyethylene and polystyrene, nonwoven fabrics, glass fibers, hollow ceramics, composites of these, etc. It can also be used.

Regarding the embodiment described above, the following additional notes are further disclosed.
(Appendix 1) a first thermal conductor;
At least one thermoelectric conversion element provided above the first thermal conductor and thermally connected to the first thermal conductor;
A heat insulator provided outside the thermoelectric conversion element above the first heat conductor;
A second thermal conductor provided above the thermoelectric conversion element, thermally connected to the thermoelectric conversion element, and having a flexible fin;
The thermoelectric conversion module characterized by including.

(Additional remark 2) The said 2nd heat conductor is formed using the sheet material which has a softness | flexibility, The thermoelectric conversion module of Additional remark 1 characterized by the above-mentioned.
(Supplementary note 3) The thermoelectric conversion module according to supplementary note 2, wherein the second thermal conductor is formed by laminating a plurality of flexible sheet materials.

(Appendix 4) The thermoelectric conversion module according to appendix 2 or 3, wherein the fin is formed by bending a sheet material used for the second heat conductor.
(Supplementary Note 5) The thermoelectric conversion module according to any one of Supplementary Notes 2 to 4, wherein the sheet material used for the second thermal conductor is a graphite sheet.

(Supplementary note 6) The thermoelectric conversion module according to any one of supplementary notes 2 to 4, wherein the sheet material used for the second thermal conductor is a metal foil.
(Supplementary note 7) The thermoelectric conversion module according to any one of supplementary notes 1 to 6, wherein the first thermal conductor is formed using a flexible sheet material.

(Supplementary note 8) The thermoelectric conversion module according to supplementary note 7, wherein the first thermal conductor is formed by laminating a plurality of flexible sheet materials.
(Additional remark 9) The sheet material used for the said 1st heat conductor is a graphite sheet, The thermoelectric conversion module of Additional remark 7 or 8 characterized by the above-mentioned.

(Additional remark 10) The sheet material used for the said 1st heat conductor is metal foil, The thermoelectric conversion module of Additional remark 7 or 8 characterized by the above-mentioned.
(Additional remark 11) The said heat insulator is formed using the material which has a softness | flexibility, The thermoelectric conversion module in any one of Additional remark 1 thru | or 10 characterized by the above-mentioned.

(Supplementary Note 12) When including a plurality of the thermoelectric conversion elements,
A plurality of the thermoelectric conversion elements are provided above the first thermal conductor and spaced apart from each other.
The thermoelectric conversion module according to any one of appendices 1 to 11, wherein

(Supplementary Note 13) The second thermal conductor is provided above each of the plurality of thermoelectric conversion elements.
The thermoelectric conversion module as set forth in Appendix 12, characterized in that.

  (Additional remark 14) The thermoelectric conversion module in any one of Additional remark 1 thru | or 13 further including the resin layer provided in the opposite side to the said thermoelectric conversion element of a said 1st heat conductor.

10, 20, 30, 1000 Thermoelectric conversion module 11 Thermoelectric conversion element 11a, 11b Heat transfer element 11c Semiconductor block 11d Terminal 11e Lead electrode 11p P-type semiconductor block 11n N-type semiconductor block 12, 22, 32 Heat absorber 13, 23, 33 , 1010 Radiator 13a Sheet material 13b, 22b, 22d, 23b, 23d, 33b, 33d Adhesive layer 13c, 23c, 33c, 1012 Fin 13d, 1011 Metal base 13da, 35a Fin mounting part 14, 24, 34 Insulator 16 Resin Layer 22a, 23a, 33a Graphite sheet 23e Underlayer 25, 35 Heat transfer block 33aa End part 100 Target 110 Arm

Claims (6)

A first thermal conductor;
At least one thermoelectric conversion element provided above the first thermal conductor and thermally connected to the first thermal conductor;
A heat insulator provided outside the thermoelectric conversion element above the first heat conductor;
A second thermal conductor provided above the thermoelectric conversion element, thermally connected to the thermoelectric conversion element, and having a flexible fin;
The thermoelectric conversion module characterized by including.   The thermoelectric conversion module according to claim 1, wherein the second heat conductor is formed using a flexible sheet material.   The thermoelectric conversion module according to claim 2, wherein the fin is formed by bending a sheet material used for the second thermal conductor.   The thermoelectric conversion module according to claim 2 or 3, wherein the sheet material used for the second thermal conductor is a graphite sheet.   The thermoelectric conversion module according to claim 1, wherein the first heat conductor is formed using a flexible sheet material.   The thermoelectric conversion module according to claim 5, wherein the sheet material used for the first heat conductor is a graphite sheet.

Images