Thermoelectric device solder assembly mold and method of operation

Abstract

The present application relates to a kind of thermoelectric device mould technical field, specifically to a kind of thermoelectric device welding assembly mould and working method, including rotating nut, mould assembly, base assembly and rotating nut when rotating, die assembly, the lower surface of pressure block is consistent with the upper surface of thermoelectric device, rotating nut is also equipped at the diagonal of the top of die assembly, base assembly is overall recessed structure, the center part is hollow and is equipped with first recess, one boss is equipped at the four peripheral corners along recess, first arc-shaped hole groove is vertically opened in the four peripheral inner wall corners of each boss, bolt and rotating nut are detachably installed between the cooperation;The present application is cooperated by die assembly, mould assembly and base assembly, with stable, easy to control, visualization and other advantages, and uniform controllable pressure is applied to thermoelectric device, to reduce even eliminate the problem of performance decline caused by interface gap, improve the performance of thermoelectric device.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of thermoelectric device mold, in particular to a thermoelectric device welding assembly mold and working method. BACKGROUND

[0002] With the rapid development of social economy, the serious energy and environmental problems follow, and it is imminent to seek green, environmentally friendly and sustainable energy. The thermoelectric material prepared into a device can realize the direct mutual conversion of heat and electricity, has the advantages of all-solid-state, super-silence, high power density, high reliability, etc., and is the preferred power supply or refrigeration method in the fields of space exploration, micro-device power supply, chip heat dissipation, biological medicine, etc.

[0003] At present, a lot of researches have been made on thermoelectric materials, but there are still deficiencies in the research of thermoelectric devices, especially in the field of thermoelectric device preparation, there is a lack of research on welding assembly mold. A reasonable welding assembly mold not only can save time and labor for the assembly of thermoelectric devices, but also can improve the performance of thermoelectric devices and reduce the rejection rate of thermoelectric devices.

[0004] At present, the mature thermoelectric materials mainly include Bi2Te3, GeTe, PbTe, Skutterudite, etc., and the specifications of thermoelectric devices mainly include 40mm×40mm, 20mm×20mm, 15mm×15mm, 3mm×3mm, etc. The diversification of materials and sizes increases the design difficulty of the welding assembly mold of thermoelectric devices, and the commercial thermoelectric devices are all manufactured by welding method. Copper is used as electrode, and ceramic sheet with good thermal conductivity is used as cold and hot end electrical insulation plate. Through the method of copper coating, electrodes are constructed on the ceramic substrate, and then P-type and N-type thermoelectric arms are connected with the electrodes to form a "Π-type" thermoelectric unit by using traditional soldering technology. In the preparation process, the alloy solder needs to be heated to above its melting temperature. When using traditional mold for preparation, the following problems exist: 1. During heating and welding, the thermal expansion mismatch between P-type and N-type thermoelectric materials causes a gap between the thermoelectric materials and the electrode sheet, which not only affects the overall structural strength of the device, but also causes a large interface resistance in the thermoelectric device; 2. During heating and welding, due to the slow heating and welding speed, the thermoelectric material is exposed to high temperature environment for a long time, causing the surface of the thermoelectric material to be oxidized, resulting in the performance of the thermoelectric device being reduced.

[0005] The above problems seriously affect the energy conversion performance of thermoelectric devices, so there is an urgent need for a thermoelectric device welding assembly mold and working method to solve the problems raised in the background technology. SUMMARY

[0006] The present application aims to provide a thermoelectric device welding assembly mold and working method to solve the problems in the background art, which can reduce or even offset the interface gap caused by thermal expansion mismatch, quickly heat and weld the thermoelectric device, thereby avoiding long-term exposure of the thermoelectric material to high temperature environment, and is suitable for welding assembly of various specifications of thermoelectric devices.

[0007] To solve the above problems, the present application provides the following technical solutions: a rotating nut, a mold assembly for containing a thermoelectric device, a base assembly for containing the mold assembly, and a pressing mold assembly that can press the pressing block to a certain depth when the rotating nut is rotated, the pressing mold assembly including a pressing block arranged on the upper surface of the thermoelectric device, the lower surface of the pressing block being in close contact with the upper surface of the thermoelectric device, the rotating nut being arranged at the opposite corners of the top of the pressing mold assembly, the base assembly including a first recess, a second recess, a protrusion, and a positioning hole, the base assembly as a whole being in a concave structure, the center of the base assembly being hollow and provided with the first recess, each protrusion being arranged at the four corner edges of the first recess, each second recess being vertically provided with a first arc-shaped hole at the four corner edges of the outer wall and the inner wall, the positioning hole being arranged at the center of the upper surface of the opposite protrusions, the bolt being detachably installed between the rotating nut, and when the rotating nut is rotated, the pressing block and the base assembly can wrap the mold assembly containing the thermoelectric device, wherein the mold assembly includes mold assembly A or mold assembly B, the pressing mold assembly includes pressing mold assembly A or pressing mold assembly B, and the base assembly includes base assembly A or base assembly B.

[0008] Preferably, the mold assembly A further includes a heat-conducting sheet and a fitting block, the fitting block being fixedly installed around the four corners of the heat-conducting sheet and forming a first recess cavity for containing the thermoelectric device, each fitting block being in close contact with the upper middle part of each surface of the heat-conducting sheet, the bottom of each fitting block being embedded with the second recess, the bottom of the heat-conducting sheet being embedded with the first recess, the length and width of the heat-conducting sheet being 0.2 mm shorter than the length and width of the first recess, the length and width of the pressing block being 0.2 mm shorter than the length and width of the first recess cavity, the length and width of the thermoelectric device being equal to the length and width of the pressing block, and the distance from the bottom of the fitting block to the bottom of the heat-conducting sheet being higher than the height of the first recess.

[0009] Preferably, the pressing mold assembly A includes a spring, a screw, a nut, a pressing block, and a first gasket, the first gasket being square-shaped, the first gasket being centrally provided with four screws along the central axis, each screw being provided with a matching spring, the top end of each screw being provided with a nut and being fixedly installed on the upper surface of the first gasket, and the smooth surface of the screw being provided with a scale line.

[0010] Preferably, the material of the base assembly A is alloy steel 40Cr, the material of the heat-conducting sheet and the pressing block is aluminum alloy 6061, the spring type is YB2x10x15, the spring material is SWPB, the spring turns are set to 4 turns, the spring coefficient K is 8000g / mm, the screw material is 40Cr, and the material of the first gasket is alloy steel 40Cr.

[0011] Preferably, the application includes a working method of a thermoelectric device welding assembly mold, characterized in that:

[0012] Step one: pressure alignment, according to the calculation, eliminate the stress applied to the thermoelectric device by the interface gap of the Bi2Te3-based thermoelectric device, that is, the pressure value of the pressing block applied to the thermoelectric device, and then according to the spring coefficient K of the selected spring, calculate the length of the spring compression when the required pressure is reached, that is, the scale value on the corresponding screw.

[0013] Step two: assembly stage, install the positioning hole on the protruding block with the bolt, and assemble the heat-conducting sheet and the matching block formed as a whole with the first recess and the second recess on the base assembly, after assembly, place the first ceramic copper-clad plate coated with solder paste into the first recess, then use a diamond wire to cut the thermoelectric material into a plurality of thermoelectric particles, the thermoelectric material of the thermoelectric particles is divided into N-type and P-type, then assemble the P-type and N-type thermoelectric particles alternately arranged, then fill the P-type and N-type thermoelectric particles alternately arranged in the first ceramic copper-clad plate coated with solder paste through the thermoelectric particle filling mold, and reserve the position of the soldering wire, then place the second ceramic copper-clad plate coated with solder paste on the upper surface of the alternately arranged P-type and N-type thermoelectric particles, and finally place the pressing block on the upper surface of the second ceramic copper-clad plate to press the assembled thermoelectric device, so that the pressing block wraps the thermoelectric device inside the first recess.

[0014] Step three: welding stage, install four screws with springs through nuts in a square symmetric manner at the center of the first gasket, then assemble the bolt and the rotating nut, and at the same time, manually rotate or use an electric wrench to rotate the two rotating nuts to apply pressure to the pressing block placed above the thermoelectric device, and stop rotating the rotating nut when the first gasket is lowered to the corresponding screw scale value calculated in step one and remains parallel to the scale value, then place the entire welding assembly mold on the heating table and heat it in a 300℃ environment for 5 minutes, then place it on an aluminum heat sink to cool down, and finally take out the thermoelectric device and the soldering wire.

[0015] Preferably, the mold assembly B further comprises a heat-conducting sheet, a matching block, a bottom sheet and a module, the matching block is fixedly installed around the periphery of the heat-conducting sheet and forms a first recess cavity for containing the bottom sheet and the module, each matching block is mutually attached to the middle upper part of each face of the heat-conducting sheet, the bottom of each matching block is mutually embedded with the second recess, the bottom of the heat-conducting sheet is mutually embedded with the first recess, the bottom of the bottom sheet is mutually embedded with the first recess cavity, the upper surface of the bottom sheet is symmetrically provided with a pair of modules along the central axis thereof, the second recess cavity for containing the thermoelectric device is formed between the two modules and the bottom sheet, the top corners around the periphery of the second recess cavity are vertically provided with second arc-shaped holes for releasing thermal expansion stress, the diameters of the second arc-shaped holes and the first arc-shaped holes are the same and are 3mm, the length of the heat-conducting sheet is 0.2mm shorter than the length of the first recess, the length of the bottom sheet is 0.2mm shorter than the length of the first recess cavity, the length of the pressing block is 0.2mm shorter than the length of the second recess cavity, the distance from the bottom of the matching block to the bottom of the heat-conducting sheet is slightly greater than the height of the second recess, and the length and width of the thermoelectric device are the same as the length and width of the pressing block.

[0016] Preferably, the mold assembly B comprises a spring, a screw, a nut, a pressing block and a second gasket, the second gasket is in the shape of a long strip, the second gasket is provided with one screw along the central part of the axis thereof, the screw is provided with a spring matched thereon, the top end of the screw is provided with a nut for fixedly installing the screw on the upper surface of the second gasket, and the screw is a screw with a scale.

[0017] Preferably, the material of the base assembly B is alloy steel 40Cr, the materials of the heat-conducting sheet, the bottom sheet and the pressing block are all aluminum alloy 6061, the spring is YB2*10mm*15mm, the material of the spring is SWPB, the number of turns of the spring is 4, the spring coefficient K is 8000g / mm, the material of the screw is 40Cr, and the material of the second gasket is alloy steel 40Cr.

[0018] Preferably, the present application comprises another working method of a thermoelectric device welding assembly mold, characterized in that:

[0019] Step one: pressure matching, according to the calculation, the stress applied on the thermoelectric device by eliminating the interface gap of the Bi2Te3-based thermoelectric device is obtained, that is, the pressure value of the pressing block applied on the thermoelectric device, and then according to the spring coefficient K of the selected spring, the length of the spring compression when the required pressure is reached is calculated, that is, the scale value on the corresponding screw.

[0020] Step two: assembly stage, the positioning hole on the protruding block is matched and installed with the bolt, the integrated heat-conducting sheet and the matching block are assembled with the first groove and the second groove on the mold assembly, then the integrated bottom sheet and the module are assembled and placed in the first recess cavity, then the first ceramic copper-clad sheet coated with solder paste is placed in the second recess cavity, then the thermoelectric material is cut into several thermoelectric particles by using a diamond wire, the thermoelectric material of the thermoelectric particles is divided into N type and P type, then the P type and N type thermoelectric particles are alternately arranged and assembled, then the P type and N type thermoelectric particles alternately arranged are filled on the first ceramic copper-clad sheet coated with solder paste by the thermoelectric particle filling mold, and the position of the soldering wire is reserved, then the second ceramic copper-clad sheet coated with solder paste is placed on the upper surface of the P type and N type thermoelectric particles alternately arranged, and finally the pressing block is placed on the upper surface of the second ceramic copper-clad sheet to press the assembled thermoelectric device, so that the pressing block wraps the thermoelectric device in the second recess cavity.

[0021] Step three: welding stage, one screw with a spring is installed in the center of the second gasket through a nut, then the two rotating nuts installed at the opposite corners of the second gasket are assembled with the bolts fixedly installed at the opposite corners of the protruding block, at the same time, the pressure of the pressing block placed above the thermoelectric device is applied by manually rotating or using an electric wrench to rotate the two rotating nuts, when the second gasket is lowered to the corresponding screw scale value calculated in step one and keeps parallel with the scale value, the rotation of the rotating nut is stopped, then the whole welding assembly mold is placed on a heating table and heated at 300 DEG C for 5 minutes, then it is cooled on an aluminum profile heat sink, finally the thermoelectric device is taken out with the soldering wire.

[0022] Compared with the prior art, the beneficial effects of the present application are:

[0023] 1、 the present application, according to the type of thermoelectric device to be processed, if the size to be processed is 40mm*40mm or other slightly larger thermoelectric device size, the first recess cavity formed by the increased heat-conducting sheet and the matching block is used for containing it, if the size to be processed is 20mm*20mm, 15mm*15mm, 3mm*3mm or other slightly smaller thermoelectric device size, the second recess cavity formed by the newly added bottom sheet and the module is used for containing it, so that the mold can adapt to thermoelectric devices of multiple specifications at the same time, greatly improving the adaptability of the mold product;

[0024] 2、The heat-conducting sheet of the present application is embedded with the first recess and the matching block, and the distance from the bottom of the matching block to the bottom of the heat-conducting sheet is higher than the height of the first recess. When the base assembly is pulled up by the spring force, the heat-conducting sheet protrudes from the base assembly. The height difference design makes the heat-conducting sheet fully and uniformly contact with the heating platform, avoiding the direct contact between the base assembly and the heating platform, and eliminating the influence of the base assembly on the heating temperature, so that the high-temperature contact part of the mold can fully contact with the heating platform, improving the thermal effect.

[0025] 3、The heat-conducting sheet of the high-temperature contact part of the heating platform is made of aluminum alloy material with high thermal conductivity, and the pressing block, the bottom sheet and the module are also made of aluminum alloy material with high thermal conductivity. The first recess formed by the added heat-conducting sheet and the matching block is used to hold the thermoelectric device, and the second recess formed by the added bottom sheet and the module is used to hold the thermoelectric device. In addition, the pressing block placed on the upper surface of the thermoelectric device fully wraps the thermoelectric device to form a "wrapped shape". In this way, heat can be quickly conducted to each welding point, accelerating the welding speed, quickly heating and welding the thermoelectric device, reducing the time of the thermoelectric material in a high-temperature environment, avoiding the long-term exposure of the thermoelectric material in a high-temperature environment, and reducing the oxidation degree of the thermoelectric material. The remaining base assembly, first gasket and second gasket are made of high-strength alloy steel material. The high-strength alloy steel material has good comprehensive mechanical properties, good low-temperature impact toughness, low notch sensitivity and good cutting performance after quenching and tempering, so that the mold can withstand high pressure and high temperature, ensuring the strength requirements of the mold.

[0026] 4、A scale line is arranged on the outer surface of the smooth section of the screw, so that the pressure applied by the spring in real time can be visualized when the rotating nut is rotated, facilitating reading and ensuring that the pressure required by the thermoelectric device when the first gasket or the second gasket is pressed down is kept flush.

[0027] 5、If the size of the processed thermoelectric device is 40mm*40mm or slightly larger, the square first gasket and the four square springs are arranged to apply stable and uniform pressure to the thermoelectric device, if the size of the processed thermoelectric device is 20mm*20mm, 15mm*15mm, 3mm*3mm or slightly smaller, the long strip-shaped second gasket and the single spring are arranged to apply stable and uniform pressure to the thermoelectric device, since the thermoelectric device is mostly a ceramic insulating sheet, the mechanical performance of the thermoelectric device is poor, and excessive concentrated force can cause the device to crack and break, the addition of the square pressing block changes the concentrated force into a plane uniform force, so that the stress on the thermoelectric device is more uniform, thereby reducing or even eliminating the interface gap caused by the mismatch of thermal expansion, and different sizes of the thermoelectric device are equipped with different sizes of the gasket, so that the stress on the thermoelectric device is more uniform, compared with the traditional thermoelectric device welding assembly mold, the thermoelectric device assembled by the application has small interface resistance and low oxidation degree of the thermoelectric material at high temperature, which improves the performance of the thermoelectric device and realizes the preparation of high-performance thermoelectric device.

[0028] 6、The first arc-shaped hole with a diameter of 3mm for releasing thermal expansion stress is vertically arranged at the outer wall corner of each protruding block and the inner wall corner of each second recess, and the second arc-shaped hole with a diameter of 3mm for releasing thermal expansion stress is vertically arranged at the top corner of the second recess, the first arc-shaped hole and the second arc-shaped hole are both thermal expansion release areas, and the jamming phenomenon caused by thermal expansion between the mold assembly and the base assembly is avoided. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 It is an explosion process structure schematic diagram of the thermoelectric device welding assembly mold of the embodiment one of the application;

[0030] Figure 2 It is a whole structure schematic diagram of the assembly mold and the thermoelectric device cooperating with each other in the embodiment one of the application;

[0031] Figure 3 It is Figure 2 It is a cross-sectional top view schematic diagram of the thermoelectric device in the embodiment one of the application;

[0032] Figure 4 It is Figure 2 It is a cross-sectional side view schematic diagram of the thermoelectric device in the embodiment one of the application;

[0033] Figure 5 It is an explosion process structure schematic diagram of the thermoelectric device welding assembly mold of the embodiment two of the application;

[0034] Figure 6 It is a whole structure schematic diagram of the assembly mold and the thermoelectric device cooperating with each other in the embodiment two of the application;

[0035] Figure 7 For Figure 6 The cross-sectional top view of the thermoelectric device in the second embodiment of the present application;

[0036] Figure 8 For Figure 6 The cross-sectional side view of the thermoelectric device in the second embodiment of the present application;

[0037] Figure 9 The three-dimensional structure schematic diagram of the base assembly of the present application;

[0038] Figure 10 The three-dimensional structure schematic diagram of the heat-conducting sheet and the cooperating block installation;

[0039] Figure 11 The three-dimensional structure schematic diagram of the base sheet and the module installation;

[0040] Figure 12 The stress nephogram of a first gasket in the first embodiment of the present application;

[0041] Figure 13 The stress nephogram of the base assembly in the first embodiment of the present application;

[0042] Figure 14 The stress nephogram of the heat-conducting sheet in the first embodiment of the present application;

[0043] Figure 15 The stress nephogram of a second gasket in the second embodiment of the present application;

[0044] Figure 16 The plane schematic diagram of the screw in the present application.

[0045] The reference signs in the drawing are as follows: rotating nut 1, mold assembly 2, base assembly 3, pressing mold assembly 4, pressing block 5, thermoelectric device 6, first recess 7, second recess 8, protruding block 9, positioning hole 10, first arc-shaped hole groove 11, bolt 12, heat-conducting sheet 13, cooperating block 14, first recess cavity 15, spring 16, screw 17, nut 18, first gasket 19, first block of ceramic copper-clad sheet 20, thermoelectric particle 21, second block of ceramic copper-clad sheet 22, base sheet 23, module 24, second recess cavity 25, second arc-shaped hole groove 26, second gasket 27. DETAILED DESCRIPTION

[0046] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0047] Please refer to Figures 1-16An embodiment provided by the present application:

[0048] A hot electric device welding assembly mold and working method, comprising a rotating nut 1, a mold assembly 2 for containing a hot electric device 6, a base assembly 3 for containing the mold assembly 2, and a pressing mold assembly 4 capable of pressing a pressing block 5 to a certain depth when the rotating nut 1 is rotated, the pressing mold assembly 4 comprises a pressing block 5 arranged on the upper surface of the hot electric device 6, the lower surface of the pressing block 5 is in close contact with the upper surface of the hot electric device 6, and the rotating nut 1 is arranged at the opposite corners of the top of the pressing mold assembly 4, the base assembly 3 comprises a first groove 7, a second groove 8, a protrusion 9 and a positioning hole 10, the base assembly 3 is in a concave structure, the center part is hollow and provided with the first groove 7, a protrusion 9 is arranged at each corner of the periphery of the first groove 7, a first arc-shaped hole 11 for releasing thermal expansion stress is vertically arranged at the outer wall corner of each protrusion 9 and the inner wall corner of each second groove 8, the designed first arc-shaped hole is a thermal expansion release area, which avoids the jamming phenomenon caused by thermal expansion between the mold assembly and the base assembly; the positioning hole 10 for installing a bolt 12 is arranged at the center of the upper surface of the opposite protrusions 9, the bolt 12 and the rotating nut 1 are detachably and cooperatively installed, when the rotating nut 1 is rotated, the pressing block 5 and the base assembly 3 can wrap the mold assembly 2 containing the hot electric device 6 respectively, wherein the mold assembly 2 comprises a mold assembly A or a mold assembly B, the pressing mold assembly 4 comprises a pressing mold assembly A or a pressing mold assembly B, and the base assembly 3 comprises a base assembly A or a base assembly B.

[0049] The following is a specific embodiment of the first embodiment provided by the present application:

[0050] When preparing a hot electric device 6 with a size of 40mm*40mm, 127 pairs of Bi2Te3 hot electric particles 21, and a hot electric particle 21 with a size of 1.2mm*1.2mm*1.4mm:

[0051] Please refer to Figure 1 、 Figure 3 、 Figure 4 and Figure 10In the embodiment, further, the mold assembly A further comprises a heat-conducting sheet 13 and a fitting block 14, the fitting block 14 is fixedly installed around the periphery of the heat-conducting sheet 13 and forms a first recess cavity 15 for containing the thermoelectric device 6, and each fitting block 14 is mutually adhered to the middle upper part of each face of the heat-conducting sheet 13, the bottom of each fitting block 14 is mutually embedded with the second recess 8, the bottom of the heat-conducting sheet 13 is mutually embedded with the first recess 7, the length and width of the heat-conducting sheet 13 are respectively 0.2 mm shorter than the length and width of the first recess 7, the length and width of the pressing block 5 are respectively 0.2 mm shorter than the length and width of the first recess cavity 15, the length and width of the thermoelectric device 6 are respectively equal to the length and width of the pressing block 5, and the distance from the bottom of the fitting block 14 to the bottom of the heat-conducting sheet 13 is higher than the height of the first recess 7, when the base assembly 3 is pulled up by the spring force, the heat-conducting sheet 13 protrudes from the base assembly 3, the design of the height difference makes the heat-conducting sheet 13 fully and uniformly contact with the heating table, avoids the direct contact of the base assembly 3 with the heating table, eliminates the influence of the base assembly 3 on the heating temperature, so that the high-temperature contact part of the mold can fully contact with the heating table, and the heat effect is improved; the first recess cavity 15 formed by the heat-conducting sheet 13 and the fitting block 14 is used for containing the thermoelectric device 6, and the pressing block 5 placed on the upper surface of the thermoelectric device 6, so as to comprehensively wrap the thermoelectric device 6 to form a "wrapped shape", so that the heat can be quickly conducted to each welding point, the welding speed is accelerated, the thermoelectric device is quickly welded, the time of the thermoelectric material in the high-temperature environment is reduced, the thermoelectric material is prevented from being exposed in the high-temperature environment for a long time, and the oxidation degree of the thermoelectric material is reduced; wherein: the outer dimension of the base assembly 3 is 65 mm x 65 mm x 22 mm, the size of the first recess 7 is 40.4 mm x 40.4 mm, the size of the second recess 8 is 20.2 mm x 5 mm x 3 mm, the size of the heat-conducting sheet 13 is 40.2 mm x 40.2 mm x 9 mm, the size of the fitting block 14 is 20 mm x 4.9 mm x 14 mm, the size of the first recess cavity 15 is 40.2 mm x 40.2 mm x 10 mm, and the first recess cavity 15 can place the thermoelectric device 6 with a specification of 40 mm x 40 mm.

[0052] Please refer to Figure 1 , Figure 2 and Figure 16 In the embodiment, further, the mold assembly A comprises a spring 16, a screw 17, a nut 18, a pressing block 5 and a first gasket 19, the first gasket 19 is square in shape, the middle part of the first gasket 19 is symmetrically provided with four screws 17 along the central axis thereof, a matching spring 16 is sleeved and installed on each screw 17, a nut 18 is arranged at the top end of each screw 17 and is fixedly installed on the upper surface of the first gasket 19, and a scale line is arranged on the smooth outer surface of the screw 17, as Figure 16As shown; wherein the planar size of the pressing block 5 is determined according to the size of the thermoelectric device, and the sum of the thicknesses of the pressing block 5 and the thermoelectric device 6 is slightly greater than the height of the first recess 15. In this way, after the thermoelectric device is placed in the first recess 15 and pressed by the pressing block 5, the pressing block 5 can protrude from the first recess 15, so that the pressing block 5 can be in complete and sufficient contact with the bottom of the screw 17, and the stress is more uniform.

[0053] It should be noted that the material of the base assembly A is alloy steel 40Cr, the materials of the heat-conducting sheet 13 and the pressing block 5 are both aluminum alloy 6061, the spring 16 is model YB2x10x15 (wire diameter Φ2mm, spring 16 diameter Φ10mm, free height 15mm), the material of the spring 16 is SWPB, the number of turns of the spring 16 is 4 turns, the coefficient K of the spring 16 is 8000g / mm, the material of the screw 17 is 40Cr, the diameter of the smooth section of the screw 17 is 7mm and the length is 16mm, the length of the M4 external thread section is 6mm, the tail small boss of the screw 17 is Φ7.5mm and the height is 2mm; the bottom sheet of the screw 17 is Φ13mm in diameter and 3mm in height; it should be noted that the specification of the spring 16 is determined according to the required applied pressure, and the length of the screw 17 is further determined according to the determined free length of the spring 16; the material of the first gasket 19, which is the main force receiving component, is high-strength alloy steel 40Cr; the thickness of the first gasket 19 is determined by the required applied pressure, and the first gasket 19 is in a pure bending state when the pressure is applied, and the minimum cross-sectional area of the first gasket 19 is determined according to the yield strength of the material, so that the appropriate thickness is selected.

[0054] Please refer to Figures 1-4 The working method of the thermoelectric device welding assembly mold is characterized in that:

[0055] Step one: pressure alignment, according to the calculation, for a thermoelectric device 6 with a preparation size of 40mmx40mm, when the stress applied on the thermoelectric device 6 is 3.73MPa, the interfacial gap of the Bi2Te3-based thermoelectric device 6 can be eliminated, that is, the pressure applied on the thermoelectric device 6 by the pressing block 5 is 1364.3N, and then according to the coefficient K of the selected spring 16, the required pressure can be reached when the compression length of the spring 16 is 4.3mm.

[0056] Step two: assembly stage, the positioning hole 10 on the protruding block 9 is matched with the bolt 12, the integrated heat-conducting sheet 13 and the matching block 14 are matched with the first recess 7 and the second recess 8 on the base assembly 3, after the assembly is completed, the first ceramic copper-clad sheet 20 coated with solder paste is placed in the first recess cavity 15, then the thermoelectric material is cut into 1.2mmx1.2mmx1.4mm thermoelectric particles 21 using a diamond wire, the thermoelectric material of the thermoelectric particle 21 is divided into N type and P type, then the P type and N type thermoelectric particles 21 are alternately arranged for assembly, then the alternately arranged P type and N type thermoelectric particles 21 are filled on the first ceramic copper-clad sheet 20 coated with solder paste through a thermoelectric particle filling mold, and the position of the soldering wire is reserved, then the second ceramic copper-clad sheet 22 coated with solder paste is placed on the upper surface of the alternately arranged P type and N type thermoelectric particles 21, and finally the pressing block 5 is placed on the upper surface of the second ceramic copper-clad sheet 22 to press the assembled thermoelectric device 6, so that the pressing block 5 wraps the thermoelectric device 6 inside the first recess cavity 15.

[0057] Step three: soldering stage, four screws 17 provided with springs 16 are symmetrically installed in the center of the first gasket 19 through nuts 18, then the bolt 12 and the rotating nut 1 are assembled, and the pressing block 5 placed above the thermoelectric device 6 is simultaneously pressed by manually rotating or using an electric wrench to rotate the two rotating nuts 1, when the first gasket 19 is observed to be lowered to the height of the screw 17 scale of 4.3mm and parallel to 4.3mm, the rotation of the rotating nut 1 is stopped, then the whole soldering assembly mold is placed on a heating table and heated at 300℃ for 5 minutes, then it is placed on an aluminum profile heat sink for cooling, finally the thermoelectric device 6 is taken out and the soldering wire is taken out, in the soldering stage of the present example, the actual force applied by the first gasket 19 to the pressing block 5 is 1348.5N, the stress cloud diagram is as shown in Figure 10 The stress of the first gasket 19 is the largest at the edge of the hole and is 180MPa, which is much lower than the material yield strength 785MPa, and the base assembly 3 and the heat-conducting sheet 13 are the main force receiving parts, the stress cloud diagram of the base assembly 3 is as shown in Figure 13 The maximum stress of the base assembly 3 is 80MPa, which is much lower than the material yield strength 785MPa; the stress cloud diagram of the heat-conducting sheet 13 is as shown in Figure 14 The maximum stress of the heat-conducting sheet 13 is 58MPa, which is much lower than the material yield strength 276MPa of the aluminum alloy 6061.

[0058] The following is a specific implementation of the second embodiment provided by the present application:

[0059] When a thermoelectric device 6 with a size of 15mmx15mm and 17 pairs of Bi2Te3 thermoelectric particles 21 is prepared, the thermoelectric particle 21 has a size of 1.4x1.4x2.8mm:

[0060] See Figure 5 , Figures 7-8 , Figures 10-11In the embodiment, further, the mold assembly B further comprises a heat-conducting sheet 13, a fitting block 14, a bottom sheet 23 and a module 24. The fitting block 14 is fixedly installed around the periphery of the heat-conducting sheet 13 and forms a first recess cavity 15 for containing the bottom sheet 23 and the module 24. Each fitting block 14 is in close contact with the middle and upper part of each face of the heat-conducting sheet 13. The bottom of each fitting block 14 is in close fit with the second recess groove 8. The bottom of the heat-conducting sheet 13 is in close fit with the first recess groove 7. The bottom of the bottom sheet 23 is in close fit with the first recess cavity 15. A pair of modules 24 are symmetrically arranged along the central axis on the upper surface of the bottom sheet 23. The two modules 24 and the bottom sheet 23 form a second recess cavity 25 for containing the thermoelectric device 6. The top corners of the periphery of the second recess cavity 25 are vertically provided with second arc-shaped holes 26 for releasing thermal expansion stress. The diameters of the second arc-shaped holes 26 and the first arc-shaped holes 11 are both 3 mm. The length and width of the heat-conducting sheet 13 are respectively 0.2 mm shorter than the length and width of the first recess groove 7. The length and width of the bottom sheet 23 are respectively 0.2 mm shorter than the length and width of the first recess cavity 15. The length and width of the pressing block 5 are respectively 0.2 mm shorter than the length and width of the second recess cavity 25. The length and width of the thermoelectric device 6 are the same as the length and width of the pressing block 5. The distance from the bottom of the fitting block 14 to the bottom of the heat-conducting sheet 13 is higher than the height of the first recess groove 7. When the base assembly 3 is pulled up by the spring force, the heat-conducting sheet 13 protrudes from the base assembly 3. The height difference design makes the heat-conducting sheet 13 fully and uniformly contact with the heating table, avoiding the direct contact of the base assembly 3 with the heating table and the influence of the base assembly 3 on the heating temperature, so that the high-temperature contact part of the mold can fully contact with the heating table, improving the thermal effect. The second recess cavity 25 formed by the added bottom sheet 23 and the module 24 is used for containing the thermoelectric device 6, and the pressing block 5 placed on the upper surface of the thermoelectric device 6, so as to comprehensively wrap the thermoelectric device to form a "wrapped shape". In this way, heat can be quickly conducted to each welding point, the welding speed is accelerated, the thermoelectric device is quickly heated and welded, the time of the thermoelectric material in the high-temperature environment is reduced, the thermoelectric material is prevented from being exposed to the high-temperature environment for a long time, and the oxidation degree of the thermoelectric material is reduced. The outer dimensions of the base assembly 3 are 65 mm x 65 mm x 22 mm. The size of the first recess groove 7 is 40.4 mm x 40.4 mm. The size of the second recess groove 8 is 20.2 mm x 5 mm x 3 mm. The size of the heat-conducting sheet 13 is 40.2 mm x 40.2 mm x 9 mm. The size of the fitting block 14 is 20 mm x 4.9 mm x 14 mm. The size of the first recess cavity 15 is 40.2 mm x 40.2 mm x 10 mm. The size of the bottom sheet 23 is 40 mm x 40 mm x 3 mm. The size of the module 24 is 40 mm x 30 mm x 10 mm. The size of the second recess cavity 25 is 15.2 mm x 15.2 mm x 10 mm. The second recess cavity 25 can contain a thermoelectric device with a specification of 15 mm x 15 mm.

[0061] Please see Figure 5 , Figures 7-9 and Figure 16 In this embodiment, the molding assembly B further includes a spring 16, a screw 17, a nut 18, a pressure block 5, and a second washer 27. The second washer 27 is elongated, and a screw 17 is provided at the center of the second washer 27 along its central axis. A matching spring 16 is fitted onto the screw 17, and a nut 18 is provided at the top of the screw 17 to fix it to the upper surface of the second washer 27. The outer surface of the smooth section of the screw 17 is provided with scale lines, such as... Figure 16 As shown; the planar dimensions of the pressure block 5 are determined according to the dimensions of the thermoelectric device. The sum of the thicknesses of the pressure block 5 and the thermoelectric device 6 should be slightly greater than the height of the second cavity 25. In this way, after the thermoelectric device is placed in the second cavity 25 and then pressed in by the pressure block 5, the pressure block 5 can protrude from the second cavity 25. This allows the pressure block 5 to make complete and full contact with the bottom of the screw 17, resulting in more uniform force distribution.

[0062] It should be noted that, in this embodiment, the base component B is made of 40Cr alloy steel, the heat-conducting sheet 13, the base plate 23, and the pressure block 5 are all made of 6061 aluminum alloy, the spring 16 is model YB2×10mm×15mm (wire diameter Φ2mm, spring 16 mean diameter Φ10mm, free height 15mm), the spring 16 is made of SWPB, the spring 16 has 4 turns, the spring coefficient K is 8000g / mm, the screw 17 is made of 40Cr, the screw 17 has a smooth section diameter of 7mm and a length of 16mm, the M4 external thread section length is 6mm, and the screw 17 has a small boss at the tail of Φ7.5mm. The diameter of the screw 17 base plate is Φ13mm, and the height is 3mm. It should be noted that the specification of the spring 16 is determined according to the required applied pressure, and the length of the screw is further determined according to the determined free length of the spring 16. The material of the second washer 27 is 40Cr alloy steel. Here, the material of the second washer 27, which is the main load-bearing component, is high-strength 40Cr alloy steel. The thickness of the second washer 27 is determined by the required applied pressure. When pressure is applied, the second washer 27 is in a pure bending state. The minimum cross-sectional area of ​​the second washer 27 is determined according to the yield strength of the material, so as to select an appropriate thickness.

[0063] Please see Figures 5-11 In this embodiment, a method for working a thermoelectric device welding assembly mold is characterized by:

[0064] Step one: pressure calibration, according to the calculation, when the stress applied on the thermoelectric device 6 is 3.73 MPa, the interface gap of the Bi2Te3-based thermoelectric device 6 can be eliminated, that is, the pressure applied on the thermoelectric device 6 by the pressing block 5 is 248.3 N, and then according to the coefficient K of the selected spring 16, when the compression length of the spring 16 is 3.2 mm, the required pressure can be achieved.

[0065] Step two: assembly stage, the positioning hole 10 on the protruding block 9 is matched and installed with the bolt 12, the integrated heat-conducting sheet 13 and the matching block 14 are correspondingly assembled with the first recess 7 and the second recess 8 on the base assembly 3, then the integrated bottom sheet 23 and the module 24 are assembled and placed in the first recess cavity 15, then the first ceramic copper-clad sheet 20 coated with solder paste is placed in the second recess cavity 25, then the thermoelectric material is cut into 1.4*1.4*2.8 mm thermoelectric particles 21 using a diamond wire, the thermoelectric material of the thermoelectric particles 21 is divided into N-type and P-type, then the P-type and N-type thermoelectric particles 21 are alternately arranged for assembly, then the P-type and N-type thermoelectric particles 21 alternately arranged are filled on the first ceramic copper-clad sheet 20 coated with solder paste through a thermoelectric particle filling mold, and a position for welding a lead wire is reserved, then the second ceramic copper-clad sheet 22 coated with solder paste is attached and placed on the upper surface of the alternately arranged P-type and N-type thermoelectric particles 21, and finally the pressing block 5 is attached and placed on the upper surface of the second ceramic copper-clad sheet 22 to press the assembled thermoelectric device 6, so that the pressing block 5 wraps the thermoelectric device 6 inside the second recess cavity 25.

[0066] Step three: welding stage, one screw 17 with a spring 16 sleeved thereon is installed at the center of the second gasket 27 through a nut 18, then the two rotating nuts 1 installed at the opposite corners of the second gasket 27 are assembled with the bolt 12 fixedly installed at the opposite corners of the protruding block 9, at the same time, the pressing block 5 placed above the thermoelectric device 6 is applied with pressure by manually rotating or using an electric wrench to rotate the two rotating nuts 1, and the rotation of the rotating nuts 1 is stopped when the second gasket 27 is lowered to a height of 3.2 mm and is parallel to 3.2 mm, then the whole welding assembly mold is placed on a heating table and heated at 300℃ for 5 minutes, then it is cooled on an aluminum profile heat sink, and finally the thermoelectric device 6 is taken out and the lead wire is welded, in the welding stage of the present example, the base assembly 3 and the heat-conducting sheet 13 are the main force-bearing parts, since the base assembly 3 and the mold assembly 4 in the present example are the same as those in example 1, and the pressure in example 1 is much greater than that in example 2, it can be considered that example 2 meets the strength requirement.

[0067] It will be apparent to those skilled in the art that the application is not limited to the details of the above-exemplified embodiments and that the present application can be implemented in other particular forms without departing from the spirit or essential characteristics of the present application. The embodiments should therefore be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the above description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. No reference signs in the claims should be considered as limiting the scope of the claims with respect to the figures of the patent document.

Claims

1. A thermoelectric device solder assembly mold, characterized by: The utility model provides a kind of thermoelectric device compression moulding device, including rotating nut (1), the mould assembly (2) for containing thermoelectric device (6), the base assembly (3) for containing mould assembly (2) and the compression mould assembly (4) that rotating nut (1) can be pressed to certain depth when rotating, the compression mould assembly (4) includes the pressing block (5) on the upper surface of thermoelectric device (6), the lower surface of pressing block (5) is attached with the upper surface of thermoelectric device (6), the diagonal of the top of compression mould assembly (4) is equipped with rotating nut (1), the base assembly (3) includes first recess (7), second recess (8), boss (9) and positioning hole (10), the base assembly (3) is overall recessed structure, the first recess (7) is hollow in the center, a boss (9) is equipped around the four corners of the first recess (7), every second recess (8) is vertically provided with the first arc-shaped hole (11) of releasing thermal expansion stress around outer wall corner, the positioning hole (10) for installing bolt (12) is equipped in the upper surface center of diagonal boss (9), bolt (12) and rotating nut (1) can be detachably installed, when rotating, rotating nut (1) can be wrapped up and down with pressing block (5) and base assembly (3) respectively with mould assembly (2) of thermoelectric device (6) in it, wherein, mould assembly (2) includes mould assembly A or mould assembly B, compression mould assembly (4) includes compression mould assembly A or compression mould assembly B, base assembly (3) includes base assembly A or base assembly B, the mould assembly A further includes heat-conducting sheet (13) and cooperation block (14), the cooperation block (14) is fixedly installed around the four corners of heat-conducting sheet (13) and forms the first recess (15) for containing thermoelectric device (6), and every cooperation block (14) and heat-conducting sheet (13) each face middle upper part mutually attach, the bottom of every cooperation block (14) and second recess (8) mutually embed, the bottom of heat-conducting sheet (13) and the first recess (7) mutually embed, the length of the length of width of heat-conducting sheet (13) is respectively 0.2mm shorter than the length of the length of width of the first recess (7), the length of the length of width of pressing block (5) is respectively 0.2mm shorter than the length of the length of width of first recess (15), the length of width of thermoelectric device (6) is respectively equal to the length of width of pressing block (5), the distance height from the bottom of cooperation block (14) to the bottom of heat-conducting sheet (13) is higher than the height of first recess (7);The material of base assembly A adopts alloy steel 40Cr, and the material of heat-conducting sheet (13) and pressing block (5) all adopts aluminum alloy 6061.

2. A thermoelectric device solder assembly mold according to claim 1, wherein: The die assembly A includes a spring (16), a screw (17), a nut (18), a pressing block (5) and a first gasket (19), the first gasket (19) is square in shape, the middle of the first gasket (19) is symmetrically provided with four screws (17) along the central axis thereof, each screw (17) is provided with a matching spring (16) sleeved and mounted thereon, the top end of each screw (17) is provided with a nut (18) and is fixedly mounted on the upper surface of the first gasket (19), and the smooth section of the screw (17) is provided with a scale line on the outer surface thereof, wherein the spring (16) is YB2x10x15 in model, the material of the spring (16) is SWPB, the number of turns of the spring (16) is 4, and the coefficient K of the spring (16) is 8000g / mm, the material of the screw (17) is 40Cr, and the material of the first gasket (19) is alloy steel 40Cr.

3. A thermoelectric device solder assembly mold according to claim 1, wherein: The die assembly B further includes a heat-conducting sheet (13), a matching block (14), a bottom sheet (23) and a module (24), the matching block (14) is fixedly mounted around the periphery of the heat-conducting sheet (13) and forms a first recess (15) for containing the bottom sheet (23) and the module (24), and each matching block (14) is mutually adhered to the middle upper portion of each face of the heat-conducting sheet (13), the bottom of each matching block (14) is mutually embedded with the second recess (8), the bottom of the heat-conducting sheet (13) is mutually embedded with the first recess (7), the bottom of the bottom sheet (23) is mutually embedded with the first recess (15), and the upper surface of the bottom sheet (23) is symmetrically provided with a pair of modules (24) along the central axis thereof, a second recess (25) for containing a thermoelectric device (6) is formed between the two modules (24) and the bottom sheet (23), a second arc-shaped hole slot (26) for releasing thermal expansion stress is vertically formed at each top corner of the periphery of the second recess (25), the diameters of the second arc-shaped hole slot (26) and the first arc-shaped hole slot (11) are both 3mm, the length of the heat-conducting sheet (13) and the length of the width thereof are respectively 0.2mm shorter than the length of the first recess (7) and the length of the width thereof, the length of the bottom sheet (23) and the length of the width thereof are respectively 0.2mm shorter than the length of the first recess (15) and the length of the width thereof, the length of the pressing block (5) and the length of the width thereof are respectively 0.2mm shorter than the length of the second recess (25) and the length of the width thereof, the distance from the bottom of the matching block (14) to the bottom of the heat-conducting sheet (13) is slightly greater than the height of the second recess (8), and the length of the thermoelectric device (6) and the length of the width thereof are equal to the length of the pressing block (5) and the length of the width thereof.

4. A thermoelectric device solder assembly mold according to claim 3, wherein: The compression mold assembly B includes a spring (16), a screw (17), a nut (18), a pressing block (5), and a second gasket (27), the second gasket (27) is long strip-shaped, a screw (17) is arranged on the central part along the axis of the second gasket (27), the screw (17) is sleeved with a matched spring (16), the top end of the screw (17) is provided with a nut (18) to be fixedly installed on the upper surface of the second gasket (27), and the screw (17) is a screw (17) with a scale.

5. A thermoelectric device solder assembly mold according to claim 4, wherein: The material of the base assembly B is alloy steel 40Cr, the materials of the heat-conducting sheet (13), the bottom sheet (23), and the pressing block (5) are all aluminum alloy 6061, the spring (16) is YB2x10mmx15mm in model, the material of the spring (16) is SWPB, the number of turns of the spring (16) is 4, the coefficient K of the spring (16) is 8000g / mm, the material of the screw (17) is 40Cr, and the material of the second gasket (27) is alloy steel 40Cr.

6. A working method for the welding assembly mold of the thermoelectric device of claim 2, characterized in that: Step one: pressure matching, according to the calculation, the stress applied on the thermoelectric device (6) for eliminating the interface gap of the Bi2Te3-based thermoelectric device (6) is obtained, that is, the pressure value of the pressing block (5) applied on the thermoelectric device (6), and then according to the spring coefficient K of the selected spring (16), the length of the spring (16) compressed to reach the required pressure is calculated, that is, the scale value on the screw (17); Step two: assembly stage, the positioning hole (10) on the protruding block (9) is matched and installed with the bolt (12), the integrated heat-conducting sheet (13) and the matching block (14) are correspondingly assembled with the first recess (7) and the second recess (8) on the base assembly (3), after the assembly is completed, the first ceramic copper-clad sheet (20) coated with solder paste is placed in the first recess cavity (15), then the thermoelectric material is cut into a plurality of thermoelectric particles (21) by using a diamond wire, the thermoelectric material of the thermoelectric particle (21) is divided into N type and P type, then the P type and N type thermoelectric particles (21) are alternately arranged for assembly, then the P type and N type thermoelectric particles (21) alternately arranged are filled on the first ceramic copper-clad sheet (20) coated with solder paste by using the thermoelectric particle filling mold, and the position of the solder wire is reserved, then the second ceramic copper-clad sheet (22) coated with solder paste is attached and placed on the upper surface of the P type and N type thermoelectric particles (21) alternately arranged, and finally the pressing block (5) is attached and placed on the upper surface of the second ceramic copper-clad sheet (22) to press the assembled thermoelectric device (6), so that the pressing block (5) wraps the thermoelectric device (6) inside the first recess cavity (15). Step three: welding stage, install 4 screws (17) with spring (16) in the center of the first gasket (19) through the square symmetry of the nut (18), then assemble bolt (12) and rotating nut (1), and manually rotate or use electric wrench to rotate two rotating nuts (1) at the same time to apply pressure to the pressing block (5) placed above the thermoelectric device (6), and stop rotating the rotating nut (1) when the first gasket (19) drops to the corresponding screw (17) scale value calculated in step one and keeps parallel with the scale value, then place the whole welding assembly mold on the heating table and heat it in a 300℃ environment for 5 minutes, then cool it on the aluminum profile heat sink, and finally take out the thermoelectric device (6) and weld the wires.

7. A working method for a welding assembly mold for a thermoelectric device according to claim 4 or 5, characterized in that: Step one: pressure alignment, according to the calculation, eliminate the stress applied to the thermoelectric device (6) to eliminate the interface gap of the Bi2Te3-based thermoelectric device (6), that is, the pressure value applied to the thermoelectric device (6) by the pressing block (5), and then according to the spring coefficient K of the selected spring (16), calculate the length of the spring (16) compressed to reach the required pressure, which is the scale value on the corresponding screw (17); Step two: assembly stage, install the positioning hole (10) on the protrusion (9) with the bolt (12), assemble the heat-conducting sheet (13) and the matching block (14) with the first recess (7) and the second recess (8) on the base assembly (3), then assemble the bottom sheet (23) and the module (24) to form an integral whole and place them in the first recess (15), then place the first ceramic copper-clad sheet (20) coated with solder paste into the second recess (25), then use diamond wire to cut the thermoelectric material into several thermoelectric particles (21), the thermoelectric material of the thermoelectric particles (21) is divided into N-type and P-type, then arrange the P-type and N-type thermoelectric particles (21) alternately, then fill the P-type and N-type thermoelectric particles (21) arranged alternately on the first ceramic copper-clad sheet (20) coated with solder paste through the thermoelectric particle filling mold, and reserve the position of the welding wire, then place the second ceramic copper-clad sheet (22) coated with solder paste on the surface of the P-type and N-type thermoelectric particles (21) arranged alternately, and finally place the pressing block (5) on the upper surface of the second ceramic copper-clad sheet (22) to press the assembled thermoelectric device (6), so that the pressing block (5) wraps the thermoelectric device (6) in the second recess (25). Step three: welding stage, 1 set with spring (16) screw (17) through the nut (18) installed in the center of the second gasket (27), then installed in the second gasket (27) diagonal nut (1) with fixed installation in the lug (9) diagonal bolt (12) and assembly, while rotating or using electric wrench rotating two rotating nut (1) at the same time, the two rotating nut (1) placed on the top of the thermoelectric device (6) block (5) to apply pressure, to observe the second gasket (27) down to the corresponding screw (17) scale value calculated by step one and the scale value remains parallel when you can stop rotating rotating nut (1), then the whole set of welding assembly mold in the heating table in the environment of 300 ℃ heating 5 min, then put in the aluminum profile heat sink, finally the thermoelectric device (6) take out the welding wire.

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