A mold for assembling a multistage micro thermoelectric cooling device and a method of using the same

Abstract

The application provides a mold for assembling a multistage micro thermoelectric refrigeration device and a use method thereof. The mold comprises a top ceramic plate positioning template, a middle layer ceramic plate positioning frame and a bottom ceramic plate positioning template. The number of the middle layer ceramic plate positioning frame is determined according to the number of stages of the multistage device. The middle layer ceramic plate positioning frame I and the middle layer ceramic plate positioning frame II are provided for a three-stage device. The middle layer ceramic plate positioning frame I is connected with the bottom ceramic plate positioning template through positioning screw holes. The middle layer ceramic plate positioning frame II is connected with the middle layer ceramic plate positioning frame I through positioning holes. The top ceramic plate positioning template is connected with the bottom ceramic plate positioning template through positioning holes. The multistage micro thermoelectric refrigeration device prepared by the mold has the advantages of high yield, stable device performance and the like.

Description

Technical Field

[0001] This invention relates to the field of thermoelectric power generation technology, specifically to a method and mold for preparing a multi-stage micro thermoelectric cooling device. Background Technology

[0002] Temperature control and thermal management technologies play a crucial role in various fields such as national defense, aerospace, electronics and communications, public healthcare, transportation, and smart homes. Thermoelectric cooling devices are widely used due to their unique advantages, including no moving parts, no noise, and no refrigerant. However, continuous technological innovation has placed higher demands on the size and performance of thermoelectric cooling devices. For example, the electronics and communications industry requires thermoelectric cooling devices to be on the order of millimeters in size, with cooling temperatures reaching -30°C or even lower.

[0003] Currently, most thermoelectric devices on the market are single-stage devices, with dimensions exceeding 20 mm. However, single-stage devices suffer from limited cooling capacity due to heat dissipation constraints. Multi-stage devices, on the other hand, offer the advantage of multiple layers of heat dissipation, allowing the top cooling surface to reach very low cooling temperatures. Currently, the fabrication of multi-stage cooling thermoelectric devices relies on manual assembly, resulting in low yield rates. Furthermore, unsuitable assembly molds can cause misalignment between stages, leading to increased resistance and ultimately reduced overall device performance. Summary of the Invention

[0004] To address the shortcomings or improvement needs of existing technologies, this invention provides a method and mold for fabricating multi-level micro thermoelectric devices. By using bottom and top ceramic plate positioning templates and intermediate layer ceramic plate positioning frames, the relative positional relationship between each level of ceramic plate is ensured, preventing misalignment between device layers and guaranteeing the yield and performance of multi-level micro thermoelectric devices.

[0005] On one hand, the present invention provides a mold for assembling a multi-stage micro thermoelectric cooling device, wherein the multi-stage micro thermoelectric cooling device includes an N-stage structure, where N≥2 and N is an integer. The number of thermoelectric arms and the size of the ceramic plates in the N-stage structure decrease sequentially from bottom to top, forming a pagoda-like structure. The N-stage structure includes, from bottom to top, a bottom ceramic plate, a first-stage thermoelectric arm, an intermediate ceramic plate I, a second-stage thermoelectric arm, an intermediate ceramic plate II, and so on, up to the N-stage thermoelectric arm and the top ceramic plate.

[0006] The mold includes a bottom ceramic plate positioning template, N-1 intermediate ceramic plate positioning frames arranged from bottom to top, and a top ceramic plate positioning template.

[0007] The bottom ceramic plate positioning template has a groove at its center to limit the bottom ceramic plate; the top ceramic plate positioning template has a groove at its center to limit the top ceramic plate; each intermediate layer ceramic plate positioning frame has a through hole at its center, the shape of which depends on the shape of the ceramic plate, and the through hole size is smaller than the size of the ceramic plate in its current layer but larger than the size of the next layer ceramic plate, for passing through the next layer thermoelectric arm; wherein, in each of the intermediate layer ceramic plate positioning frames II to N-1, a groove adapted to the size of the ceramic plate is provided below the through hole to limit the ceramic plate in its current layer; any groove and any through hole are coaxial in the vertical direction;

[0008] The bottom ceramic plate positioning template is fixed to the middle layer ceramic plate positioning frame I, which is used to define the positions of the bottom ceramic plate, the first-stage thermoelectric arm, and the middle layer ceramic plate I; the middle layer ceramic plate positioning frame I is fixed to the middle layer ceramic plate positioning frame II, which is used to define the positions of the second-stage thermoelectric arm and the middle layer ceramic plate II, and so on. The top ceramic plate positioning template is fixed to the bottom ceramic plate positioning template, which is used to define the positions of the N-stage thermoelectric arm and the top ceramic plate.

[0009] Based on the above scheme, preferably, the preparation method of the multi-level device semi-finished product includes the following steps:

[0010] a. Preparation of bismuth telluride-based P and N-type thermoelectric materials;

[0011] b. The wire cutter cuts the thermoelectric material wafers into wafers of a certain thickness, and then electroplats a nickel layer on the surface of the wafers;

[0012] c. Cut the nickel-plated wafer into thermoelectric grains of a certain size using a wire cutting machine;

[0013] d. The thermoelectric arms are welded to the bottom ceramic plate, multiple intermediate ceramic plates and the top ceramic plate respectively to form a multi-level device semi-finished product.

[0014] Based on the above scheme, preferably, the multi-stage micro thermoelectric cooling device includes a two-stage or more-stage structure. The multi-stage structure forms a pagoda-like structure with the number of thermoelectric arms and the size of the ceramic plates decreasing sequentially from bottom to top. The two-stage device includes a bottom ceramic plate, a first-stage thermoelectric arm, a middle layer ceramic plate, a second-stage thermoelectric arm, and a top ceramic plate. The three-stage device includes a bottom ceramic plate, a first-stage thermoelectric arm, a middle layer ceramic plate I, a second-stage thermoelectric arm, a middle layer ceramic plate II, a third-stage thermoelectric arm, and a top ceramic plate. More-stage devices are combined according to the above rules.

[0015] Based on the above solution, preferably, a through hole is opened at the center of the intermediate layer ceramic plate positioning frame I. The shape of the through hole is determined according to the shape of the ceramic plate. The size of the through hole is smaller than the size of the first-stage intermediate layer ceramic plate and larger than the size of the next-stage intermediate layer ceramic plate. The lower part around the through hole is folded down to form a limiting plate to limit the intermediate layer ceramic plate I. The limiting plate is connected to a positioning platform with positioning holes. The positioning holes of the positioning platform are used to connect with the bottom positioning die and the next-stage positioning die. The left view and front view of the intermediate layer ceramic plate positioning frame I are both in the shape of "Ji".

[0016] Based on the above solution, preferably, a through hole is opened at the center of the intermediate layer ceramic plate positioning frames II to N - 1. The shape of the through hole is determined according to the shape of the ceramic plate. The size of the through hole is smaller than the size of the previous-stage intermediate layer ceramic plate and larger than the size of the next-stage ceramic plate. The two sides of the through hole are folded down to form a limiting plate to limit the intermediate layer ceramic plate. The limiting plate is connected to a positioning platform with positioning holes. The positioning holes of the positioning platform are used to connect with the upper-stage intermediate layer ceramic plate positioning frame. The front view of the intermediate layer ceramic plate positioning frame I is in the shape of "Ji".

[0017] Based on the above solution, preferably, a groove is opened at the center of the bottom ceramic plate positioning template, and positioning holes are opened at the four top corners. A positioning threaded hole is opened at the midpoint of the connection line of the positioning holes for connecting with the intermediate layer ceramic plate positioning frame. Two shallow and thin grooves are also opened on the positioning template and connected to the central groove for welding the device leads.

[0018] Based on the above solution, preferably, a groove is opened at the center of the top ceramic plate positioning template, and positioning holes are opened at the four top corners.

[0019] On the other hand, the present invention provides a method for assembling a multi-stage micro thermoelectric cooling device using the above molds. The method includes the following steps:

[0020] Step 1: Weld the thermoelectric arms to each intermediate layer ceramic plate respectively to form a semi-finished multi-stage device;

[0021] Step 2: Fix the bottom ceramic plate to the bottom ceramic plate positioning template, and fix the intermediate layer ceramic plate I welded with the thermoelectric arms to the intermediate layer ceramic plate positioning frame I. The thermoelectric arms correspond to the electrode plates on the bottom ceramic plate one by one, and connect the intermediate layer ceramic plate positioning frame I and the bottom ceramic plate positioning template through the threaded holes;

[0022] Step 3: Fix the intermediate ceramic plate II welded with the thermoelectric arms to the intermediate layer ceramic plate positioning frame II, and connect the intermediate layer ceramic plate positioning frame II and the intermediate layer ceramic plate positioning frame I through the positioning holes, so that the thermoelectric arms correspond to the back electrode plates of the intermediate layer ceramic plate I one by one;

[0023] Step 4: Repeat Step 3 multiple times until the intermediate layer ceramic plate N - 1 is fixed completely;

[0024] Step 5: Fix the top ceramic plate with the welded thermoelectric arm to the top ceramic plate positioning template, and connect the top ceramic plate positioning template to the bottom ceramic plate positioning template through the positioning holes, so that the thermoelectric arm of the top ceramic plate corresponds one-to-one with the back electrode piece of the middle layer ceramic plate N-1, and at the same time, the multi-level device is in a stable clamping state.

[0025] Step 6: Place wires into the two shallow grooves of the bottom ceramic plate positioning template, put the entire assembly into reflow soldering for welding, and remove the positioning template and the middle layer ceramic plate positioning frame after welding to complete the assembly of the multi-stage micro thermoelectric cooling device.

[0026] Beneficial effects

[0027] 1) The method for fabricating multi-stage micro thermoelectric cooling devices provided by this invention has a simple fabrication process, efficient device assembly, and high yield.

[0028] 2) The multi-level micro thermoelectric cooling device fabrication mold provided by this invention ensures the relative positions between layers, the stability of thermoelectric arms and welding sites, and provides good device performance. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the explosion of a three-stage micro thermoelectric cooling device assembly.

[0030] Figure 2 This is a cross-sectional view of a three-stage micro thermoelectric cooling device assembly.

[0031] Figure 3 This is a schematic diagram of the positioning frame I for the intermediate ceramic plate.

[0032] Figure 4 This is a schematic diagram of the intermediate ceramic plate positioning frame II.

[0033] In the figure, 1-top ceramic plate positioning template, 2-middle layer ceramic plate positioning frame II, 3-middle layer ceramic plate positioning frame I, 4-three-stage micro thermoelectric cooling device, 5-bottom ceramic plate positioning template, 6-middle layer ceramic plate II, 7-middle layer ceramic plate I, 8-thermoelectric arm, 9-top ceramic plate, 10-through hole, 11-groove. Detailed Implementation

[0034] To make the objectives and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the present invention and are not intended to limit the present invention. Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0035] The structures, proportions, sizes, etc., illustrated in the accompanying drawings of this invention are merely for illustrative purposes and to aid those skilled in the art in understanding and reading the invention. They are not limiting conditions for the implementation of this invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effects and objectives of this invention, should still fall within the scope of the technical content disclosed in this invention. Furthermore, the terms such as "upper," "lower," "left," "right," "middle," and "one" used in this invention specification are merely for clarity of description and are not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention's implementation.

[0036] Example

[0037] This embodiment provides a method and mold for fabricating a three-stage micro thermoelectric cooling device. The structure of the three-stage micro thermoelectric cooling device is as follows: the first stage uses a 6×6mm ceramic plate with 17 pairs of thermoelectric arms, the second stage uses a 4×4mm ceramic plate with 7 pairs of thermoelectric arms, and the third stage uses a 2×2mm ceramic plate with 2 pairs of thermoelectric arms.

[0038] The mold used includes bottom ceramic plate positioning template 5, middle layer ceramic plate positioning frame I3, middle layer ceramic plate positioning frame II2, and top ceramic plate positioning template 1;

[0039] The bottom ceramic plate positioning template 5 has a groove 11 at its center to limit the bottom ceramic plate; the top ceramic plate positioning template 1 has a groove 11 at its center to limit the top ceramic plate 9; both intermediate layer ceramic plate positioning frames have through holes 10 at their centers, the shape of which is determined by the shape of the ceramic plate, the size of which is smaller than the size of the ceramic plate in its current layer and larger than the size of the next layer ceramic plate, for passing through the next layer thermoelectric arm; wherein, in the intermediate layer ceramic plate positioning frame II2, a groove 11 adapted to the size of the ceramic plate is provided below the through hole to limit the ceramic plate in its current layer; any groove and any through hole are coaxial in the vertical direction;

[0040] The bottom ceramic plate positioning template 5 is fixed to the middle layer ceramic plate positioning frame I3 to define the positions of the bottom ceramic plate, the first-stage thermoelectric arm, and the middle layer ceramic plate I7; the middle layer ceramic plate positioning frame I3 is fixed to the middle layer ceramic plate positioning frame II2 to define the positions of the second-stage thermoelectric arm and the middle layer ceramic plate II6; and the top ceramic plate positioning template 1 is fixed to the bottom ceramic plate positioning template 5 to define the positions of the third-stage thermoelectric arm and the top ceramic plate 9.

[0041] The bottom ceramic plate positioning template 5 has positioning holes at its four top corners, and two opposite positioning threaded holes are opened at the midpoint of the connecting line of the positioning holes. The bottom ceramic plate positioning template 5 is also provided with two shallow and thin grooves, which are connected to the groove 11 at the center position and are used for the welding of device leads.

[0042] The through holes 10 of the middle layer ceramic plate positioning frame I3 are folded downwards around the periphery to form a limiting plate to limit the middle layer ceramic plate I7. The limiting plate is connected to a positioning platform with positioning holes. The two opposite positioning holes of the positioning platform are fixed to the positioning threaded holes of the bottom ceramic plate positioning template 5 by screws. The left view and front view of the middle layer ceramic plate positioning frame I3 are both in the shape of "Ji".

[0043] In the middle layer ceramic plate positioning frame II2, the two sides of the groove 11 are folded downwards to form limiting plates, which respectively limit the middle layer ceramic plate II6. The limiting plates are connected to a positioning platform with positioning holes. The positioning holes of the positioning platform are fixed to the positioning holes of the upper-level middle layer ceramic plate positioning frame. The front view of the middle layer ceramic plate positioning frame II2 is in the shape of "Ji".

[0044] The top ceramic plate positioning template 1 has positioning holes at its four top corners for fixing to the positioning holes around the bottom ceramic plate positioning template.

[0045] The method for assembling a multi-stage micro thermoelectric cooling device using the above-mentioned mold includes the following steps:

[0046] Step 1: Weld 17 pairs of thermoelectric arms to the middle layer ceramic plate I through the mold by reflow welding, weld 7 pairs of thermoelectric arms to the middle layer ceramic plate II through the mold by reflow welding, and weld 2 pairs of thermoelectric arms to the top ceramic plate through the mold by reflow welding;

[0047] Step 2: After welding, remove the mold for welding the thermoelectric arms to form semi-finished products of each stage of the multi-stage thermoelectric device;

[0048] Step 3: Fix the bottom ceramic plate to the bottom ceramic plate positioning template 5, and fix the ceramic plate I welded with 17 pairs of thermoelectric arms to the middle layer ceramic plate positioning frame I3, with the thermoelectric arms facing downwards corresponding to the electrode plates of the bottom ceramic plate;

[0049] Step 4: Connect the middle layer ceramic plate positioning frame I3 to the bottom ceramic plate positioning template 5 through the threaded holes, so that the thermoelectric arms welded on the middle layer ceramic plate I correspond to the electrode plates of the bottom ceramic plate one by one;

[0050] Step 5: Fix the ceramic plate II with 7 pairs of thermoelectric arms welded on to the intermediate ceramic plate positioning frame II2 (the ceramic plate II can be fixed in the groove of the intermediate ceramic plate positioning frame II2 through the adhesive layer), and connect the intermediate ceramic plate positioning frame II2 and the intermediate ceramic plate positioning frame I3 through the threaded hole so that the thermoelectric arms correspond one-to-one with the back electrode of the intermediate ceramic plate I.

[0051] Step 6: Fix the top ceramic plate with two pairs of thermoelectric arms welded on it to the top ceramic plate positioning template 1. Connect the top ceramic plate positioning template 1 to the bottom ceramic plate positioning template 5 through the positioning holes so that the thermoelectric arms of the top ceramic plate correspond one-to-one with the back electrodes of the middle layer ceramic plate II, and at the same time, put the three-stage device in a stable clamping state.

[0052] Step 7: Place the wire into the groove of the bottom ceramic plate positioning template 5, put the entire assembly into reflow soldering for welding, and remove the positioning template and the middle layer ceramic plate positioning frame after welding to complete the fabrication of the three-stage micro thermoelectric cooling device.

Claims

1. A mold for assembling a multi-stage micro thermoelectric cooling device, the multi-stage micro thermoelectric cooling device includes an N-stage structure, N≥2, N is an integer, the number of thermoelectric arms and the size of the ceramic plate in the N-stage structure decrease successively from bottom to top, forming a pagoda-like structure. The N-stage structure includes a bottom ceramic plate, a first-stage thermoelectric arm, an intermediate ceramic plate I, a second-stage thermoelectric arm, an intermediate ceramic plate II arranged successively from bottom to top, and so on until the N-stage thermoelectric arm and the top ceramic plate; The characteristics are as follows: The mold includes a bottom ceramic plate positioning template, N - 1 intermediate ceramic plate positioning frames arranged successively from bottom to top, and a top ceramic plate positioning template; A groove is opened at the center position of the bottom ceramic plate positioning template for limiting the bottom ceramic plate; a groove is opened at the center position of the top ceramic plate positioning template for limiting the top ceramic plate; a through hole is opened at the center position of any intermediate ceramic plate positioning frame, the shape of the through hole is determined according to the shape of the ceramic plate, the size of the through hole is smaller than the size of the ceramic plate at the current level and larger than the size of the ceramic plate at the next level, and is used to pass through the thermoelectric arm at the next level; Among the intermediate ceramic plate positioning frames II to N - 1, grooves adapted to the size of the ceramic plate are provided below their respective through holes for limiting the ceramic plate at the current level; any groove and any through hole are coaxial in the vertical direction; The bottom ceramic plate positioning template is fixed to the intermediate ceramic plate positioning frame I for limiting the positions of the bottom ceramic plate, the first-stage thermoelectric arm, and the intermediate ceramic plate I; the intermediate ceramic plate positioning frame I is fixed to the intermediate ceramic plate positioning frame II for limiting the positions of the second-stage thermoelectric arm and the intermediate ceramic plate II, and so on. The top ceramic plate positioning template is fixed to the bottom ceramic plate positioning template for limiting the positions of the N-stage thermoelectric arm and the top ceramic plate.

2. The mold according to claim 1, characterized in that, Positioning holes are opened at the four corners of the bottom ceramic plate positioning template, and two opposite positioning threaded holes are opened at the midpoint of the connection line of the positioning holes. Two shallow and thin grooves are also opened on the bottom ceramic plate positioning template, connected to the groove at the center position, for welding the device wires.

3. The mold according to claim 2, characterized in that, The periphery of the through hole of the intermediate ceramic plate positioning frame I is folded down to form a limiting plate to limit the intermediate ceramic plate I. The limiting plate is connected to a positioning platform with positioning holes. The two opposite positioning holes of the positioning platform are fixed to the positioning threaded holes of the bottom ceramic plate positioning template by screws. The left view and the front view of the intermediate ceramic plate positioning frame I are both in the shape of "Ji".

4. The mold according to claim 1, characterized in that, Among the intermediate ceramic plate positioning frames II to N - 1, the two sides of their respective grooves are folded down to form limiting plates, respectively limiting the intermediate ceramic plates II to N - 1. The limiting plates are connected to a positioning platform with positioning holes. The positioning holes of the positioning platform are fixed to the positioning holes of the upper-level intermediate ceramic plate positioning frame. The front views of the intermediate ceramic plate positioning frames II to N - 1 are all in the shape of "Ji".

5. The mold according to claim 2, characterized in that, Positioning holes are opened at the four corners of the top ceramic plate positioning template for fixing to the positioning holes around the bottom ceramic plate positioning template.

6. A method for assembling a multi-stage micro thermoelectric cooling device using the mold described in any one of claims 1-5, characterized in that, The method includes the following steps: Step 1: Weld the thermoelectric arms to each intermediate ceramic plate respectively to form a semi-finished multi-stage device; Step 2: Fix the bottom ceramic plate to the bottom ceramic plate positioning template, and fix the middle layer ceramic plate I with the thermoelectric arm welded to the middle layer ceramic plate positioning frame I. The thermoelectric arm corresponds one-to-one with the electrode piece on the bottom ceramic plate. Connect the middle layer ceramic plate positioning frame I to the bottom ceramic plate positioning template through the threaded hole. Step 3: Fix the intermediate ceramic plate II with the welded thermoelectric arms to the intermediate ceramic plate positioning frame II, and connect the intermediate ceramic plate positioning frame II to the intermediate ceramic plate positioning frame I through the positioning holes, so that the thermoelectric arms correspond one-to-one with the back electrode plates of the intermediate ceramic plate I. Step 4: Repeat step 3 multiple times until the intermediate ceramic plate N-1 is fixed. Step 5: Fix the top ceramic plate with the welded thermoelectric arm to the top ceramic plate positioning template, and connect the top ceramic plate positioning template to the bottom ceramic plate positioning template through the positioning holes, so that the thermoelectric arm of the top ceramic plate corresponds one-to-one with the back electrode piece of the middle layer ceramic plate N-1, and at the same time, the multi-level device is in a stable clamping state. Step 6: Place wires into the two shallow grooves of the bottom ceramic plate positioning template, put the entire assembly into reflow soldering for welding, and remove the positioning template and the middle layer ceramic plate positioning frame after welding to complete the assembly of the multi-stage micro thermoelectric cooling device.

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