JP2016171154A - Thermoelectric generator, thermoelectric module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique for facilitating the positioning at the time of manufacturing, while making positional deviation difficult to occur, when disposing a thermoelectric module for a prism member.SOLUTION: A thermoelectric generator includes a thermoelectric module 100 generating an electromotive force by the temperature difference between a first surface and a second surface spaced apart therefrom, and a prism member (passage pipe) 90 having n side faces, where n is an integer of 3 or more. In the thermoelectric generator, a temperature difference is generated by heat transmission between the side face and the first surface. The first surface includes two planes. The two planes are in contact with the side faces different from each other, out of the n side faces.SELECTED DRAWING: Figure 2

Description

  The present invention relates to thermoelectric power generation.

  2. Description of the Related Art A thermoelectric power generation apparatus is known in which a thermoelectric module (thermoelectric power generation element) is disposed on a side surface of a hexagonal columnar heat exchanger. The thermoelectric module is in contact with the side surface of the heat exchanger at the heated surface. This surface to be heated has a planar shape (Patent Document 1).

JP 2009-278767 A

  According to the arrangement of the above prior art, since the side surface of the heat exchanger and the heated surface of the thermoelectric module are flat, it is difficult to position during manufacturing and misalignment is likely to occur during use. The present invention is based on the above prior art, and it is a solution to provide a technique that is easy to position at the time of manufacture and difficult to shift at the time of use when the thermoelectric module is arranged on a prismatic member such as a hexagonal prism. To do.

  SUMMARY An advantage of some aspects of the invention is to solve the above-described problems, and the invention can be implemented as the following forms.

(1) According to one aspect of the present invention, a thermoelectric module that generates an electromotive force due to a temperature difference between the first surface and a second surface disposed apart from the first surface; n is 3 or more And a prismatic member having n side surfaces; and a thermoelectric power generation device in which the temperature difference is generated by heat transfer between the side surfaces and the first surface. In the thermoelectric generator, the first surface includes two planes; the two planes are in contact with different side surfaces of the n side surfaces. According to this aspect, by disposing the thermoelectric module at the corner portion of the polygonal column member, it is easy to position at the time of manufacture and is difficult to be displaced at the time of use. The above temperature difference may be promoted by heat transfer between the second surface and another member or atmosphere.

(2) In the above aspect, the prismatic member may be a heat medium flow path. According to this embodiment, power generation using a heat medium can be performed.

(3) In the above aspect, the cross section orthogonal to the long axis of the prismatic member at a predetermined position in the long axis direction of the prismatic member may include the n cross sections of the thermoelectric module. According to this aspect, since the thermoelectric module can be arranged over the entire circumference of the prism member, the arrangement of the thermoelectric module becomes dense and the power generation efficiency is improved.

(4) In the above embodiment, the first thermoelectric module that is a thermoelectric module having one of the n cross sections is a second thermoelectric module that is disposed closest to the first thermoelectric module. The first surface is hotter than the second surface during thermoelectric generation; between the first surfaces of the first and second thermoelectric modules; The distance may be greater than or equal to the distance between the second surfaces of the first and second thermoelectric modules. According to this aspect, the first surface becomes hotter than the second surface during use. Therefore, the first surface is more thermally expanded than the second surface. Therefore, as in this embodiment, by setting the distance between the first surfaces to be equal to or greater than the distance between the second surfaces, the first and second thermoelectric modules can be used even when the interval between the first and second thermoelectric modules is reduced. And it becomes easy to avoid that 2nd thermoelectric modules interfere.

(5) In the above embodiment, an angle connecting the two side surfaces in a cross section orthogonal to each of the n side surfaces is an R shape, and all angles as inner angles are inferior angles; The connecting corner is R-shaped; the radius of curvature of the R shape as the corner connecting the planes may be smaller than the radius of curvature of the R shape as the corner connecting the side surfaces. According to this aspect, when the thermoelectric module is arranged on the prismatic member, a gap is formed at the corner. Therefore, it is possible to avoid the corner of the prism member from interfering with the thermoelectric module.

(6) In the above aspect, the thermoelectric module may include a plurality of thermoelectric power generation elements stacked. According to this embodiment, the above-described embodiment can be realized with a laminated thermoelectric module.

(7) In the above embodiment, the outer surface of the thermoelectric module is provided with an electrical insulation coating; the thermoelectric module may include an electrode penetrating the electrical insulation coating to extract the electromotive force. According to this form, it can arrange so that parts other than an electrode may be in contact with an electric conductor.

(8) In the above aspect, the prism member may include a convex portion for positioning the thermoelectric module in the major axis direction of the prism member. According to this embodiment, the thermoelectric module can be easily positioned in the major axis direction of the prismatic member.

(9) In the above-described embodiment, a first heat conductor that is disposed between the side surface and the first surface and promotes heat transfer between the side surface and the first surface is provided; The first surface may contact via the first thermal conductor. According to this form, heat transfer between the prismatic member and the first surface is improved.

(10) The said form WHEREIN: You may provide the jig | tool for fixing the said thermoelectric module to the said prismatic member. According to this embodiment, the thermoelectric module can be fixed to the prismatic member.

(11) In the above-described embodiment, a temperature difference promoting member that promotes the generation of the temperature difference by heat transfer with the second surface is provided; between the second surface and the temperature difference promoting member You may provide the 2nd heat conductor which arrange | positions and accelerates | stimulates the heat transfer between the said 2nd surface and the said temperature difference acceleration | stimulation member. According to this form, heat transfer between the second surface and the temperature difference promoting member is improved.

(12) In the above aspect, the temperature difference promoting member may include a fin. According to this form, generation | occurrence | production of a temperature difference is accelerated | stimulated more.

  The present invention can be realized in various forms other than the above. For example, it can be realized in the form of a thermoelectric module or the like.

The perspective view which shows the outline of a thermoelectric generator. The perspective view which shows a mode that the thermoelectric module was arrange | positioned at the flow-path pipe | tube. The perspective view of a thermoelectric module. The side view of a thermoelectric module. The enlarged view of the area | region R. FIG. The perspective view which shows a flow-path pipe. Process drawing which shows the outline of the manufacturing method of a thermoelectric module. The detailed process drawing about sheeting of a thermoelectric material. The front view of the thermoelectric sheet | seat after a cutting | disconnection. The end elevation near the center of the thermoelectric sheet after cutting. Process drawing which shows the preparation procedures of the 1st and 2nd unit sheet | seat. The front view after the printing of the paste for insulating layers. The end elevation near the center after printing of the paste for insulating layers. The front view after printing of the paste for contact conductive parts. The end elevation near the center after printing of the paste for contact conductive parts. The front view after the printing of the paste for conductive layers. The end elevation near the center after printing of the paste for conductive layers. Process drawing which shows the preparation procedures of the 1st and 2nd end sheet | seat. The front view after the printing of the paste for insulating layers. The end elevation near the center after printing of the paste for insulating layers. The front view after printing of the paste for contact conductive parts. The end elevation near the center after printing of the paste for contact conductive parts. The front view after the printing of the paste for insulating layers. The end elevation near the center after printing of the paste for insulating layers. The end elevation near the center after printing of paste for electrodes. The front view after the printing of the paste for insulating layers. The end elevation near the center after printing of the paste for insulating layers. The front view after printing of the paste for contact conductive parts. The end elevation near the center after printing of the paste for contact conductive parts. The front view after the printing of the paste for conductive layers. The end elevation near the center after printing of the paste for conductive layers. The front view after the printing of the paste for insulating layers. The end elevation near the center after printing of the paste for insulating layers. The front view after printing of the paste for contact conductive parts. The end elevation near the center after printing of the paste for contact conductive parts. The front view after the printing of the paste for insulating layers. The end elevation near the center after printing of the paste for insulating layers. The end elevation near the center after printing of paste for electrodes. Sectional drawing of a laminated body. The side view of a laminated body. The virtual diagram which shows a process site | part. The expanded sectional view of a thermoelectric generator. The figure which shows a thermoelectric module (modification). The figure which shows a thermoelectric module (modification).

  FIG. 1 is a perspective view showing an outline of the thermoelectric generator 50. FIG. 1 shows a part of the thermoelectric generator 50 in the long axis direction (Z1 direction). The thermoelectric generator 50 is mounted on an automobile that uses an internal combustion engine as a power source. The thermoelectric generator 50 includes a fixing member 60, a flow channel tube 90, and a plurality of thermoelectric modules 100.

  The flow path pipe 90 is a pipe for flowing a fluid having a temperature higher than that of the atmosphere, specifically, exhaust gas from the internal combustion engine. The channel tube 90 is made of stainless steel or the like. The channel tube 90 is a hollow member having an approximately polygonal column shape, and more specifically, is a hollow member having an approximately regular dodecagonal column (see FIG. 2). The flow channel tube 90 includes a plurality of positioning members 91. The positioning member 91 will be described later with reference to FIG.

  The fixing member 60 is made of stainless steel, and includes a first main body 61, a second main body 62, two screw fixing portions 63, a plurality of fins 66, and a plurality of protrusions 68. Each of the 1st and 2nd main bodies 61 and 62 has a shape (henceforth a bowl shape) like a bowl. The saddle shape here is a shape obtained by dividing a cylinder into two by a plane including the central axis of the cylinder. The first and second main bodies 61 and 62 sandwich the thermoelectric module 100 installed in the flow channel tube 90 with a bowl-shaped inner peripheral surface. The screw fixing part 63 is a part for fixing the first and second main bodies 61 and 62 with the thermoelectric module 100 sandwiched therebetween with screws. The protrusions 68 are protrusions provided at both ends of the first main body 61 and the second main body 62. The protrusion 68 sandwiches the thermoelectric module 100 from both sides so that the position of the fixing member 60 does not shift with respect to the thermoelectric module 100.

  In a state where the thermoelectric module 100 is sandwiched, the inner peripheral surfaces of the first and second main bodies 61 and 62 are in contact with the surface to be cooled 103 (see FIG. 3) of the thermoelectric module 100 to cool the surface to be cooled. The fins 66 project radially outward from the first body 61 or the second body 62. The fins 66 promote the above-described cooling using air cooling. This air cooling uses the head wind when the car is running.

  The thermoelectric module 100 is a laminated type and a unileg type, and contacts the outer peripheral surface of the flow channel tube 90 in a state where it is arranged as a part of the thermoelectric module 100. The thermoelectric module 100 generates an electromotive force generated by thermoelectric power generation in which a contact surface with the flow channel tube 90 is a heated surface 101 (see FIG. 3) and an outer peripheral surface facing the heated surface 101 is a cooled surface 103. That is, the thermoelectric module 100 generates an electromotive force using a temperature difference between the heated surface 101 and the cooled surface 103. The plurality of thermoelectric modules 100 are connected to each other in series by a wiring 105 that connects the electrodes 139 to each other, and supplies electromotive force to an external device.

  FIG. 2 is a perspective view showing a state in which the thermoelectric module 100 is arranged in the flow channel tube 90. That is, the fixing member 60 and the wiring 105 are removed from the thermoelectric generator 50. FIG. 2 is also a cross-sectional view and shows a cross section in the plane D1. The plane D1 is a virtual plane parallel to the X1Y1 plane. The X1Y1 plane is orthogonal to the Z1 direction.

  Since the flow channel tube 90 is a hollow member having a regular dodecagonal column, it has twelve side surfaces as outer surfaces. Accordingly, FIG. 2 shows a cross section of 12 thermoelectric modules 100. Each of the twelve side surfaces functions as a heating surface that transfers heat from the exhaust gas. Each of the twelve thermoelectric modules 100 is arranged so as to come into contact with two adjacent side surfaces of the twelve side surfaces of the flow channel tube 90.

  FIG. 3 is a perspective view of one thermoelectric module 100. The thermoelectric module 100 includes a heated surface 101 and a cooled surface 103. The heated surface 101 includes an A plane 101A and a B plane 101B so as to be able to contact two adjacent side surfaces as described above. The A plane 101A and the B plane 101B are planes that are in a positional relationship intersecting each other. The crossing angle between the A plane 101A and the B plane 101B is about 150 degrees in accordance with the interior angle of the regular dodecagon.

  FIG. 4 is a side view of the thermoelectric module 100. FIG. 5 is an enlarged view of the region R shown in FIG. As shown in FIG. 5, in the region R, the thermoelectric module 100 includes a thermoelectric sheet 110a, an insulating layer 120a, a contact conductive portion 130a, a conductive layer 135a, a conductive layer 235a, an insulating layer 220a, and a thermoelectric sheet 210a that are sequentially stacked. It has a structure. The thermoelectric sheet 110a functions as a thermoelectric power generation element. With this structure, as described above, the laminated type and unileg type thermoelectric modules 100 are realized.

  Note that the boundary lines in the thermoelectric module 100 shown in FIG. 5 are shown for convenience of explanation, and in reality, a clear boundary as shown in FIG. 5 is not visually recognized. This also applies to end views (described later) showing the state before firing.

  FIG. 6 is a perspective view showing the entire flow path tube 90. The flow channel tube 90 includes a plurality of positioning members 91. The positioning member 91 is formed integrally with the flow channel tube 90. The positioning member 91 is a convex portion (protrusion) for positioning the thermoelectric module 100 in the major axis direction. Each thermoelectric module 100 is disposed between two positioning members 91 arranged in the long axis direction.

  FIG. 7 is a process diagram showing an outline of a method for manufacturing the thermoelectric module 100. First, a thermoelectric sheet material is formed into a sheet (step S300).

FIG. 8 is a detailed process diagram for making a thermoelectric material into a sheet. First, calcium carbonate (CaCO ₃ ) and cobalt oxide (III) (Co ₂ O ₃ ) are mixed (step S310). This mixing is performed according to the molar ratio of calcium cobalt oxide (Ca ₃ Co ₄ O ₉ ). Subsequently, calcining is performed at 850 ° C. for 5 hours to generate calcium / cobalt oxide (step S320).

Next, a dispersion mixed solution is prepared by primary dispersion of the powder (step S330). The ratio of _mixing, Ca 3 _Co 4 _{O 9} (thermoelectric material powder) is 65 mass%, dispersant 2 mass%, ethanol 13% by weight, toluene 20% by weight. Ethanol and toluene are added as organic solvents. The mixing time is set to 5 hours.

  Subsequently, a varnish is produced (step S340). A varnish is a dissolved product of a binder, a plasticizer, and an organic solvent. The dissolution ratio is 20% by mass for the binder, 5% by mass for the plasticizer, and 75% by mass for the organic solvent. A butyral system (for example, BM-2 (trade name)) is used for the binder. As the plasticizer, phthalic acid-based dibutyl phthalate (DOP) is used. As the organic solvent, 30% by mass of ethanol and 45% by mass of toluene are used. The dissolution time of the varnish is set to 12 hours.

  Next, varnish is added to the dispersion liquid mixture, and slurry is prepared by pot mill mixing (step S350). The mixing ratio is 80% by mass for the dispersion and 20% by mass for the varnish. The mixing time is set to 5 hours.

  Subsequently, a thermoelectric sheet is formed from the prepared slurry (step S360). For this molding, sheet casting by a doctor blade method is used. The thermoelectric sheet functions as a thermoelectric power generation element after firing (step S800 described later).

  Next, as shown in FIG. 7, the created thermoelectric sheet is cut (step S390). FIG. 9 shows a front view of the thermoelectric sheet 110 after cutting. FIG. 10 shows an end view near the center of the thermoelectric sheet 110 after cutting. As shown in FIG. 9, the shape of the thermoelectric sheet 110 is a rectangle. The thickness of the thermoelectric sheet 110 is set to 100 μm after firing. Step S300 is performed so as to obtain the number of thermoelectric sheets 110 necessary for use in the steps described later. The thermoelectric sheet 110 forms the thermoelectric sheet 110a described above after firing.

  Subsequently, the first unit sheet 140 is created (step S400). FIG. 11 is a process diagram showing a procedure for producing the first unit sheet 140. First, as shown in FIGS. 12 and 13, the insulating layer paste 120 is printed on the thermoelectric sheet 110 (step S410). The insulating layer paste 120 forms the above-described insulating layer 120a after firing.

  FIG. 12 shows a front view of the insulating layer paste 120 after printing. FIG. 13 shows an end view near the center after the insulating layer paste 120 is printed. As shown in FIGS. 12 and 13, the insulating layer paste 120 is not printed on a part of the thermoelectric sheet 110 in order to ensure conduction in the thickness direction. Screen printing is used for this printing.

  In addition, since FIG. 13 is not a cross-sectional view, what is visible behind the cut surface is not shown. In the case of a cross-sectional view, the insulating layer paste 120 present at the back of the cut surface is illustrated in the stepped portion in FIG. On the other hand, in FIG. 13 which is an end view, the insulating layer paste 120 is not shown in that portion. The same applies to the other end views.

As a material of the insulating layer paste 120 in the present embodiment, Si—Ca—Ba-based glass (softening point 830 ° C., density 3.0 g / cm ³ ) is used. Since the glass material has fluidity at a temperature equal to or higher than the softening point, the shape of the glass material can be changed in accordance with expansion and contraction of the thermoelectric sheet 110 due to firing. This property can suppress cracking of the thermoelectric module 100 due to firing. Furthermore, glass materials generally have a low thermal conductivity. Therefore, it contributes to suppression of the thermal conductivity of the entire thermoelectric module 100.

  The insulating layer paste 120 is prepared by kneading raw material powder with a predetermined amount of an organic solvent and a binder. The insulating layer paste 120 is printed so that the thickness of the insulating layer after firing becomes 20 μm. According to this thickness, both the heat conductivity of the insulating layer after firing and the ease of printing of the insulating layer paste 120 can be achieved.

  Next, the contact conductive part paste 130 is printed (step S420). The contact conductive portion paste 130 forms the above-described contact conductive portion 130a after firing. FIG. 14 shows a front view of the contact conductive part paste 130 after printing. FIG. 15 is an end view of the vicinity of the center after the contact conductive portion paste 130 is printed.

  As shown in FIGS. 14 and 15, the contact conductive portion paste 130 is printed on the exposed thermoelectric sheet 110 without printing the insulating layer paste 120. The thickness of the contact conductive portion paste 130 is set to be the same as the thickness of the insulating layer paste 120. Screen printing is used for this printing. The contact conductive part paste 130 is made of silver paste. The contact conductive portion paste 130 is prepared by kneading a predetermined amount of an organic solvent and a binder into raw material powder.

  Subsequently, the conductive layer paste 135 is printed (step S430). The conductive layer paste 135 forms the above-described conductive layer 135a after firing. FIG. 16 shows a front view of the conductive layer paste 135 after printing. FIG. 17 shows an end view near the center after the conductive layer paste 135 is printed. The first unit sheet 140 is printed with the conductive layer paste 135.

  When the conductive layer paste 135 is printed, the contact conductive portion paste 130 and the conductive layer paste 135 are integrated. However, in FIG. 17, for convenience, the boundary between the contact conductive portion paste 130 and the conductive layer paste 135 is shown.

  The conductive layer paste 135 is printed on the entire surface so that the thickness of the conductive layer after firing is 10 μm. As the material of the conductive layer paste 135, the same material as that of the contact conductive portion paste 130 is used. Screen printing is used for printing the conductive layer paste 135.

  Next, as shown in FIG. 7, a first end sheet 141 is produced (step S440). FIG. 18 is a process diagram showing a procedure for producing the first end sheet 141. First, steps S410 and S420 described above are performed.

  Subsequently, the insulating layer paste 122 is printed on the insulating layer paste 120 and the contact conductive portion paste 130 prepared in step S420 (step S450). FIG. 19 shows a front view of the insulating layer paste 122 after printing. FIG. 20 shows an end view near the center after the insulating layer paste 122 is printed.

  As shown in FIGS. 19 and 20, the insulating layer paste 122 is formed so as to expose the vicinity of the center of the insulating layer paste 120 and a part of the contact conductive portion paste 130.

  Next, the contact conductive portion paste 137 is printed (step S460). FIG. 21 shows a front view of the contact conductive part paste 137 after printing. FIG. 22 shows an end view near the center after the contact conductive portion paste 137 is printed. As shown in FIGS. 21 and 22, the contact conductive portion paste 137 is formed so as to fill a portion not covered with the insulating layer paste 122.

  Subsequently, the insulating layer paste 124 is printed (step S470). FIG. 23 shows a front view of the insulating layer paste 124 after printing. FIG. 24 shows an end view near the center after the insulating layer paste 124 is printed. As shown in FIGS. 23 and 24, the insulating layer paste 124 is formed so as to expose the contact conductive portion paste 137 in the vicinity of the center.

  Next, the electrode paste 139 is printed (step S480). The electrode paste 139 forms the electrode 139a after firing. FIG. 25 shows an end view near the center after the electrode paste 139 is printed. Note that FIG. 23 is also used for the description after step S480 because only the sign changes before and after the electrode paste 139 is printed. As shown in FIGS. 23 and 25, the electrode paste 139 is formed so as to fill a portion not covered with the insulating layer paste 124.

  As shown in FIG. 25, the electrode paste 139 is electrically connected to the thermoelectric sheet 110 through the contact conductive portion pastes 130 and 137.

  Then, as shown in FIG. 7, the 2nd unit sheet 240 is produced (step S500). Since the procedure for producing the second unit sheet 240 is similar to the procedure for producing the first unit sheet 140, it will be described with reference to FIG. The contents not specifically described are the same as those of the first unit sheet 140.

  First, as shown in FIGS. 26 and 27, the insulating layer paste 220 is printed on the thermoelectric sheet 210 (step S410). The thermoelectric sheet 210 forms the above-described thermoelectric sheet 210a after firing. The insulating layer paste 220 forms an insulating layer 220a after firing.

  FIG. 26 shows a front view of the insulating layer paste 220 after printing. FIG. 27 shows an end view near the center after the insulating layer paste 220 is printed. Note that the end view of FIG. 27 shows that the layer to be printed is located on the lower side of the page. The same applies to the following end views.

  The thermoelectric sheet 210 is produced in the same manner as the thermoelectric sheet 110. The thermoelectric sheet 210 is used for the production of the second unit sheet 240 and is given a different reference from the thermoelectric sheet 110 for convenience.

  Next, the contact conductive part paste 230 is printed (step S420). The contact conductive portion paste 230 forms a contact conductive portion 230a (reference numeral is shown in FIG. 41) after firing. FIG. 28 shows a front view of the contact conductive part paste 230 after printing. FIG. 29 shows an end view in the vicinity of the center after printing of the contact conductive portion paste 230. As shown in FIGS. 28 and 29, the contact conductive portion paste 230 is printed on the exposed thermoelectric sheet 210 without the insulating layer paste 220 being printed.

  Subsequently, the conductive layer paste 235 is printed (step S430). The conductive layer paste 235 forms a conductive layer 235a after firing. FIG. 30 shows a front view of the conductive layer paste 235 after printing. FIG. 31 shows an end view near the center after the conductive layer paste 235 is printed. The second unit sheet 240 is printed with the conductive layer paste 235.

  Next, as shown in FIG. 7, the second end sheet 241 is produced (step S540). Since the procedure for producing the second end sheet 241 is similar to the procedure for producing the first end sheet 141, it will be described with reference to FIG. The contents not particularly described are the same as those of the first end sheet 141.

  First, steps S410 and S420 are performed. Subsequently, as shown in FIGS. 32 and 33, the insulating layer paste 222 is printed on the insulating layer paste 220 and the contact conductive portion paste 230 produced in step S420 (step S450). FIG. 32 shows a front view of the insulating layer paste 222 after printing. FIG. 33 shows an end view near the center after the insulating layer paste 222 is printed.

  As shown in FIGS. 32 and 33, the insulating layer paste 222 is formed so as to expose the vicinity of the center of the insulating layer paste 220 and a part of the contact conductive portion paste 230.

  Next, the contact conductive part paste 237 is printed (step S460). FIG. 34 shows a front view of the contact conductive part paste 237 after printing. FIG. 35 shows an end view in the vicinity of the center of the contact conductive portion paste 237 after printing. As shown in FIGS. 34 and 35, the contact conductive portion paste 237 is formed so as to fill a portion not covered with the insulating layer paste 222.

  Subsequently, the insulating layer paste 224 is printed (step S470). FIG. 36 shows a front view of the insulating layer paste 224 after printing. FIG. 37 shows an end view near the center after the insulating layer paste 224 is printed. As shown in FIGS. 36 and 37, the insulating layer paste 224 is formed so as to expose the contact conductive portion paste 237 in the vicinity of the center.

  Next, the electrode paste 239 is printed (step S480). FIG. 38 shows an end view near the center after the electrode paste 239 is printed. Note that FIG. 36 is also used for the explanation after step S480 because only the sign changes before and after the electrode paste 239 is printed. As shown in FIGS. 36 and 38, the electrode paste 239 is formed so as to fill a portion not covered with the insulating layer paste 224.

  As shown in FIG. 38, the electrode paste 239 is electrically connected to the thermoelectric sheet 110 via the contact conductive portion pastes 230 and 237.

  Subsequently, as shown in FIG. 7, lamination is performed (step S550). Specifically, the first unit sheet 140, the first end sheet 141, the second unit sheet 240, the second end sheet 241 and the thermoelectric sheet 110 shown in FIG. 9 are laminated.

  FIG. 39 is a cross-sectional view of the stack obtained in step S550. The cut surface is the same as the cut surface shown in FIG. FIG. 40 is a side view of the laminate obtained in step S550.

  As shown in FIGS. 39 and 40, in step S550, the first end sheet 141 is disposed at one end of the stack. Eight separately prepared thermoelectric sheets 110 are sandwiched between the thermoelectric sheet 110 side of the first end sheet 141 and the thermoelectric sheet 210 side of the second unit sheet 240. The conductive layer paste 135 of the first unit sheet 140 is adjacent to the conductive layer paste 235 side of the second unit sheet 240. Eight thermoelectric sheets 110 are sandwiched between the thermoelectric sheet 110 side of the first unit sheet 140 and the thermoelectric sheet 210 side of another second unit sheet 240. In this manner, the second unit sheets 240 and the first unit sheets 140 are alternately arranged while sandwiching the eight thermoelectric sheets 110. A second end sheet 241 is disposed at the end opposite to the first end sheet 141.

  The reason why the eight thermoelectric sheets 110 are sandwiched as described above is to increase the overall thickness. In the present embodiment, as described above, the thermoelectric sheets 210 and the nine thermoelectric sheets 110 are laminated so as to be continuous. In step S550, 10 sets of 10 thermoelectric sheets are stacked as a whole. Therefore, 100 thermoelectric sheets are laminated as a whole. Since one thermoelectric sheet is 100 μm, the thickness of the thermoelectric module 100 obtained by firing the laminate is about 10 mm (about 10,000 μm). Since the insulating layer paste 120 and the conductive layer paste 135 are thick, the thickness is actually slightly larger than the thickness of the thermoelectric sheet 110.

  As shown in FIG. 39, the electrode paste 139 and the electrode paste 239 are conducted through the first and second unit sheets 140 and 240.

  Subsequently, as shown in FIG. 7, the laminated body thus laminated is pressure-bonded (step S600). Next, degreasing is performed (step S700). The degreasing conditions are set according to the amount of binder contained in the first unit sheet 140, the amount of dispersant, and the size of the laminate. Specifically, the degreasing temperature is set to 250 ° C., the degreasing time is set to 10 hours, and the atmosphere is set to the atmosphere.

  Next, firing is performed (step S800). Specifically, the firing is performed at a firing temperature of 900 ° C., a firing time of 5 hours, and an atmosphere of air.

  Subsequently, the outer shape is processed (step S900). FIG. 41 is a virtual diagram in which the contour line of the laminated body after firing, the contact conductive portion 130a, and the contact conductive portion 230a are projected on the X2Y2 plane. FIG. 41 shows a portion to be excised by processing by hatching. A wire saw is used for this processing.

  Finally, an electrically insulating coating is applied (step S950). In the present embodiment, step S950 is realized by applying a solution type coating species such as alumina sol or silica sol, and drying and baking. Thereby, the thermoelectric module 100 shown in FIG. 3 is completed.

  The electrically insulating coating is applied to the entire outer periphery of the thermoelectric module 100. However, the electrode 139a (not shown) and the electrode 239a (not shown) formed by firing the electrode paste 239 are exposed from the electrically insulating coating. When the electrodes 139a and 239a are exposed, it can be electrically connected to the outside.

  After the predetermined number of thermoelectric modules 100 are manufactured by the above procedure, the thermoelectric modules 100 are arranged on the outer surface of the flow pipe 90, the wiring 105 is provided, and the thermoelectric generator 50 is fixed by the fixing member 60. Complete.

  FIG. 42 is an enlarged cross-sectional view of the thermoelectric generator 50. The cut surface is a plane D1 (see FIG. 2). As shown in FIG. 42, the A plane 101A and the B plane 101B are connected by an R portion 102 having an R shape. The radius of curvature of the R portion 102 is R1. In FIG. 3 and the like, the R portion 102 is omitted for illustration. The side surfaces of the channel tube 90 are also connected in an R shape. The radius of curvature of this R shape is R2. Since R1 <R2, a gap is formed between the R portion 102 and the flow channel tube 90.

  As shown in FIG. 42, the thermoelectric module 100 is arranged such that a gap is left between the thermoelectric module 100 that is closest to the thermoelectric module 100. The distance DH that is the gap between the heated surfaces 101 is larger than the distance DC that is the gap between the cooled surfaces 103.

  Grease is applied to the outer surface of the channel tube 90 and the heated surface 101. This grease is a heat conductor and promotes heat transfer from the outer surface of the flow path tube 90 to the heated surface 101. Similarly, grease is applied to the cooled surface 103 and the fixing member 60. Due to this grease, generation of a temperature difference between the heated surface 101 and the cooled surface 103 is further promoted.

  Note that the angles θ (FIG. 42) formed by the adjacent side surfaces of the channel tube 90 are all inferior angles (<180 degrees), specifically about 150 degrees.

  According to the above embodiment, in addition to the effects described so far, at least the following effects can be obtained.

  Since the heated surface 101 includes two planes (A plane 101A and B plane 101B), the heated surface 101 can be disposed so as to straddle the corner of the flow channel tube 90. As a result, it is easy to position at the time of arrangement, and positional deviation hardly occurs after the arrangement. In particular, in the above embodiment, the thermoelectric generator 50 is loaded with vibration because it is mounted on an automobile. Even if vibration is loaded in this way, according to the present embodiment, positional deviation can be suppressed.

  Furthermore, compared with the case where the heated surface 101 is in contact with the side surface of the channel tube 90 by three or more planes, the channel tube 90 can be easily positioned at the time of arrangement, and there is a positional deviation after the arrangement. Hard to occur. This is because if there are two planes, they are less susceptible to thermal expansion and dimensional errors.

  Since twelve thermoelectric modules 100 are arranged over one circumference of the outer periphery of the dodecagonal column-shaped channel tube 90, a large number of thermoelectric modules 100 can be arranged with respect to the installation area. As a result, the thermoelectric modules 100 connected in series can be increased, and the generated voltage in the entire thermoelectric generator 50 can be increased. As a result, conversion loss can be reduced when converting to a predetermined voltage.

  The distance between the thermoelectric modules 100 can be reduced as much as possible while avoiding the interference of the thermoelectric modules 100 with the thermal expansion of the thermoelectric modules 100. This is because the distance DH, which is the gap between the heated surfaces 101, is larger than the distance DC, which is the gap between the cooled surfaces 103, as shown in FIG.

  Since the radius R1 of the R portion 102 is smaller than the R-shaped radius R2 that connects the side surfaces of the flow channel tube 90, it is possible to avoid the corners of the flow channel tube 90 from interfering with the heated surface 101.

  Since an electrically insulating coating is applied to the outer surface of the thermoelectric module 100, the thermoelectric module 100 can be brought into contact with the stainless steel channel tube 90. Furthermore, by disposing the electrodes 139a and 239a near the center in the plane direction of the thermoelectric module 100, the electrodes 139a and 239a are prevented from conducting with the positioning member 91.

  Since the electrically insulating coating is applied to the thermoelectric module 100, in addition to electrical insulation, it is possible to suppress contamination received from the atmosphere during use, deterioration associated with a chemical reaction, and the like.

  Since the fixing member 60 also has a cooling function, the thermoelectric generator 50 can be configured simply and lightly. Such a feature is particularly beneficial for use in automobiles.

  Since the material of the insulating coating is an inorganic material as described above, the durability against heating by the channel tube 90 is good.

  The present invention is not limited to the embodiments, examples, and modifications of the present specification, and can be implemented with various configurations without departing from the spirit of the present invention. For example, the technical features in the embodiments, examples, and modifications corresponding to the technical features in the embodiments described in the summary section of the invention are to solve some or all of the above-described problems, or In order to achieve part or all of the effects described above, replacement or combination can be performed as appropriate. If the technical feature is not described as essential in this specification, it can be deleted as appropriate. For example, the following modifications are illustrated.

  FIG. 43 shows the thermoelectric module 100a. In the thermoelectric module 100a, the cooled surface 103 includes two planes. In addition, the cooled surface 103 may have any shape.

  FIG. 44 shows the thermoelectric module 100b. In the thermoelectric module 100 b, the surface to be cooled 103 includes two planes, and the area of the surface to be heated 101 is substantially the same as that of the surface to be cooled 103.

As described above, the shape of the heated surface 101 may be any shape as long as two planes are included. For example, three or more planes may be included, and a curved surface may be included.
The gap between the heated surfaces may be the same as the gap between the cooled surfaces. In this way, unnecessary gaps between thermoelectric modules can be filled.

The material of the channel tube and the fixing member may be changed to another material that is resistant to the use environment.
The positioning member may be formed separately from the flow channel tube and then joined to the flow channel tube.
The positioning member may be an annular member connected over the entire circumference of the channel tube.

The channel tube may not include a positioning member.
When the channel tube does not include the positioning member, the first and second end sheets may not be stacked in the manufacture of the thermoelectric module 100. This is because if there is no positioning member, it is easy to ensure insulation from the flow path member even if there is no electrode.

  The member (heating member) for heating the surface to be heated may not be a flow channel tube, but may be any member as long as it has an n-prism shape. n is an integer of 3 or more. For example, a shape other than a regular polygonal column may be used, or a cross-sectional shape having a dominant angle (> 180 degrees) may be used. The hollow portion may have a cylindrical shape.

  The heating member may not be a hollow member. For example, the cross section may be a concave shape. That is, a shape obtained by removing one side surface from a hollow quadrangular prism may be used. Such a shape is also included in the n-prism shape in the present application. In the case of such a shape, a liquid is preferable as the heat medium flowing inside the heating member. In addition, a solid member may be used.

The surface to be cooled may be cooled by water. In the case of an automobile, the cooling water of the radiator may be used or a water cooling jacket may be installed on the fixed member.
Cooling may be realized by a member other than the fixing member.
Cooling may not be performed.

The heating member may not be an automobile pipe, and may be, for example, a pipe installed in a factory. In this case, the factory waste water may be used for water cooling of the surface to be cooled.
The n-prism member may cool the thermoelectric module, and the fixing member may heat the thermoelectric module.

The thermoelectric material may be changed. For example, telluride (Bi ₂ Te ₃ ), silicide (Mg ₂ Si, MnSi _γ , FeSi ₂ ), skutterudite (CoSb ₃ ), and oxide (Na _X CoO ₂ , SrTiO ₃ , TiO ₂ ) It may be adopted. Which one is adopted may be selected according to the intended use temperature range.

The component ratio in the dispersion mixture for obtaining the slurry may be 35 to 75% by mass for the thermoelectric material powder, 0.5 to 5% by mass for the dispersant, and 20 to 60% by mass for the total amount of the organic solvent.
The mixing time of the dispersion liquid mixture may be 0.5 to 30 hours.
Boulders may be added to the dispersion mixture. Dispersibility is improved by the addition of cobblestone. The type of cobblestone is arbitrary, and a material having a hardness that does not generate contamination due to its own wear during the dispersion treatment, such as Al ₂ O ₃ , ZrO _2, etc., is preferable.

The component ratio of the varnish may be 5 to 30% by mass of the binder, 1 to 15% by mass of the plasticizer, and 40 to 85% by mass of the total organic solvent.
The dissolution time of the varnish may be 1 to 30 hours.
The binder may be any material such as butyral or cellulose.
The plasticizer may be another phthalic acid type diisooctyl phthalate (DIOP) or the like.
The organic solvent may include other solvents having relatively high volatility. For example, methyl ethyl ketone (MEK) may be included.

The ratio of the dispersion mixture to the varnish may be 70 to 90% by mass for the dispersion mixture and 10 to 30% by mass for the varnish. The mixing time after adding the varnish may be 0.5 to 30 hours.
The thermoelectric sheet may be formed by extrusion or the like.

As the material for the insulating layer, oxide glass such as silicon dioxide (SiO ₂ ) may be used.
The material of the insulating layer may be a material whose resistivity is sufficiently higher than that of the thermoelectric material. For example, an oxide material having high stability even at a high temperature, such as Al ₂ O ₃ or MgO, may be used.

  As described with the embodiment, the thickness of the insulating layer paste is preferably not too thin from the viewpoint of productivity. Specifically, a thickness of 0.1 μm or more is preferable after firing, and a thickness of 1 μm or more is more preferable.

  The thickness of the insulating layer obtained by firing the insulating layer paste is preferably not too thick from the viewpoint of heat transfer. Specifically, it is preferably 100 μm or less, and more preferably 1 to 30 μm or less.

Metal mask printing or the like may be used for printing the insulating layer paste.
The insulating layer may be printed on the entire surface of the thermoelectric sheet. In this case, the portion for printing the contact conductive part paste may be formed by removing the insulating layer by laser processing or the like.

Metal mask printing or the like may be used for printing the contact conductive part paste.
Since the contact conductive part is an electrode part for electrically connecting adjacent thermoelectric elements, the material of the contact conductive part is equal to or less than that of the thermoelectric element, and its electrical characteristics are set during the firing process and use. Materials that are not lost are preferred. For example, gold, platinum, copper, palladium, nickel, carbon, or the like, or an alloy thereof may be used.

The material of the conductive layer paste may be different from the material of the contact conductive part paste.
Metal mask printing or the like may be used for printing the conductive layer paste.
The printed pattern of the conductive layer paste may be a pattern that can be electrically connected to the thermoelectric element through the contact conductive portion, and may be formed, for example, on a part of the insulating layer.

  The firing conditions may be changed. For example, the firing temperature may be changed to 800 to 940 ° C. and the firing time may be changed to any one of 1 to 100 hours. By changing the firing temperature or firing time, the particle size of the pre-fired portion can be changed to an arbitrary size. Alternatively, the atmosphere may be oxygen.

  You may change the conditions of degreasing. For example, the degreasing temperature may be set to 200 to 500 ° C., and the degreasing time may be set to 1 to 100 hours.

  Instead of laminating and press-bonding the printed unit sheets and then polishing, the unit sheets may be laminated and pressure-bonded after being cut into a desired shape.

  It is also possible to form a printing pattern at several places on one large thermoelectric sheet, cut it out, and carry out lamination / crimping / cutting.

  You may shape | mold the shape of a lamination direction into a desired thing with the jig | tool used for crimping | bonding. For example, the jig is provided with an inclination on the crimping surface so that the heated surface is shorter than the cooled surface.

As a method for forming the shape in the surface direction by processing, polishing, a cutting machine, or the like may be used.
Thermoelectric modules may be electrically connected in parallel.
The configuration form of the stacked thermoelectric module may be changed. For example, a PN junction type module using a P-type thermoelectric material and an N-type thermoelectric material may be used.

The material for the insulating coating is not particularly limited as long as it is resistant to heat from a high-temperature heat source, and may be selected from various materials such as inorganic and organic materials.
Instead of the grease, another heat conductor resistant to the use environment, for example, a heat transfer sheet may be used. Alternatively, the heat conductor may not be used.

DESCRIPTION OF SYMBOLS 50 ... Thermoelectric power generator 60 ... Fixing member 61 ... 1st main body 62 ... 2nd main body 63 ... Screw fixing | fixed part 66 ... Fin 68 ... Protrusion 90 ... Channel pipe 91 ... Positioning member 100 ... Thermoelectric module 100a ... Thermoelectric module 100b ... Thermoelectric Module 101 ... Heated surface 101A ... A plane 101B ... B plane 103 ... Cooled surface 105 ... Wiring 110 ... Thermoelectric sheet 110a ... Thermoelectric sheet 120 ... Insulating layer paste 120a ... Insulating layer 122 ... Insulating layer paste 124 ... Insulating layer Paste 130 ... Contact conductive part paste 130a ... Contact conductive part 135 ... Conductive layer paste 135a ... Conductive layer 137 ... Contact conductive part paste 139 ... Electrode paste 140 ... First unit sheet 141 ... First end sheet 210 ... thermoelectric sheet 210a ... thermoelectric sheet 220 ... pace for insulating layer 220a ... Insulating layer 222 ... Insulating layer paste 224 ... Insulating layer paste 230 ... Contact conductive part paste 235 ... Conductive layer paste 235a ... Conductive layer 237 ... Contact conductive part paste 239 ... Electrode paste 239a ... Electrode 240 ... Second unit sheet 241 ... second end sheet

Claims (15)

A thermoelectric module that generates an electromotive force due to a temperature difference between a first surface and a second surface disposed apart from the first surface;
n is an integer greater than or equal to 3, and a prismatic member having n side surfaces,
A thermoelectric generator that generates the temperature difference due to heat transfer between the side surface and the first surface,
The first surface includes two planes;
The two planes are in contact with different side surfaces among the n side surfaces. The thermoelectric generator according to claim 1, wherein the prism member is a flow path of a heat medium. The cross section orthogonal to the major axis of the prismatic member at a predetermined position in the major axis direction of the prismatic member includes the n sections of the thermoelectric module. Thermoelectric generator. The first thermoelectric module, which is a thermoelectric module having one of the n cross sections, is spaced from the second thermoelectric module, which is the thermoelectric module disposed closest to the first thermoelectric module. Arranged,
The first surface is hotter than the second surface during thermoelectric generation,
The distance between the first surfaces of the first and second thermoelectric modules is equal to or greater than the distance between the second surfaces of the first and second thermoelectric modules. Thermoelectric generator. The angle connecting the two side surfaces in the cross section orthogonal to each of the n side surfaces is an R shape, and all the angles as the inner angles are inferior angles,
The corner connecting the two planes is R-shaped,
5. The radius of curvature of the R shape as an angle connecting the planes is smaller than the radius of curvature of the R shape as an angle connecting the side surfaces. The thermoelectric generator as described. The thermoelectric generator according to any one of claims 1 to 5, wherein the thermoelectric module includes a plurality of stacked thermoelectric generator elements. The outer surface of the thermoelectric module is provided with an electrically insulating coating,
The thermoelectric generator according to any one of claims 1 to 6, wherein the thermoelectric module includes an electrode penetrating the electrical insulating coating in order to extract the electromotive force. The thermoelectric generator according to any one of claims 1 to 7, wherein the prismatic member includes a convex portion for positioning the thermoelectric module in a major axis direction of the prismatic member. . A first thermal conductor disposed between the side surface and the first surface and promoting heat transfer between the side surface and the first surface;
The thermoelectric generator according to any one of claims 1 to 8, wherein the side surface and the first surface are in contact with each other via the first thermal conductor. The thermoelectric power generator according to any one of claims 1 to 9, further comprising a jig for fixing the thermoelectric module to the prism member. A temperature difference accelerating member that promotes the generation of the temperature difference by heat transfer with the second surface;
A second heat conductor that is disposed between the second surface and the temperature difference promoting member and promotes heat transfer between the second surface and the temperature difference promoting member is provided. The thermoelectric power generator according to any one of claims 1 to 10. The thermoelectric generator according to claim 11, wherein the temperature difference promoting member includes a fin. A thermoelectric module that generates an electromotive force due to a temperature difference between a first surface and a second surface disposed apart from the first surface,
The first surface includes two planes. The thermoelectric module, wherein: The thermoelectric module according to claim 13, comprising a plurality of stacked thermoelectric power generation elements. The outer surface of the thermoelectric module has an electrically insulating coating,
The thermoelectric module according to claim 13 or 14, further comprising an electrode penetrating the electrically insulating coating to extract the electromotive force.

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