A magnetocaloric module with a vorticonic heat conduction enhancing sheet

Abstract

The application discloses a magnetic heat module with a spiral heat-conducting enhancement sheet, which comprises a shell, a heat-conducting assembly and a magnetic heat material, and a sealed cavity is arranged in the shell; the heat-conducting assembly comprises a heat-conducting enhancement sheet and a heat-conducting rod, the heat-conducting enhancement sheet is wound into a spiral shape and is axially arranged in the sealed cavity, the heat-conducting enhancement sheet is connected with the shell, and the heat-conducting enhancement sheet is provided with the heat-conducting rod at both ends in the axial direction, and the heat-conducting rod is axially arranged at both ends of the shell; the magnetic heat material is arranged in the gap of the heat-conducting enhancement sheet; and an opening, which is communicated with the sealed cavity, is arranged on the side wall of the shell. The magnetic heat module with the spiral heat-conducting enhancement sheet makes it more convenient to arrange the heat bus, the assembly is simple, the heat transfer in the magnetic heat material is more uniform, the thermal resistance of the magnetic heat module is smaller, and the sealing performance of the shell at both ends of the magnetic heat module is ensured.

Description

Technical Field

[0001] This invention relates to the field of cryogenic thermal insulation and demagnetization refrigeration, and particularly to a magnetocaloric module with a vortex-shaped thermally conductive thin sheet. Background Technology

[0002] In recent years, cryogenic refrigeration technology, which achieves temperatures below 1 K, has played a crucial role in condensed matter physics, space exploration, and quantum computing. Among these technologies, adiabatic demagnetization refrigeration is one of the three most mainstream methods for achieving extremely low temperatures. It is a refrigeration technology that covers a wide temperature range, has high intrinsic efficiency, does not rely on gravity, and has readily available working fluids. The magnetocaloric module is the most important component of a magnetic refrigerator, and the magnetocaloric material is the core of the magnetocaloric module.

[0003] At extremely low temperatures, the thermal conductivity of magnetocaloric materials is poor, resulting in significant temperature differences within the material. To reduce these differences, a heat bus is typically used as a heat transfer enhancement structure to improve the thermal conductivity of the magnetocaloric material. This usually involves placing hundreds or thousands of metal wires forming the heat bus within a container. Crystals are then grown directly within the container containing the metal wires. To minimize the eddy current heat generated by changes in the external magnetic field, the diameter of the metal wires is usually designed to be relatively small. Consequently, the process of threading hundreds or thousands of fine metal wires presents challenges, including complex threading, difficulty in operation, and the challenge of evenly arranging them within the magnetocaloric material growth container. Furthermore, to facilitate better heat transfer, the two ends of the heat bus outside the magnetocaloric material are often welded together as a single copper rod, which can easily lead to significant contact thermal resistance due to poor contact. Summary of the Invention

[0004] To address at least one of the problems mentioned in the background art, the present invention aims to provide a magnetocaloric module with a vortex-shaped thermally enhanced sheet.

[0005] This invention is achieved through the following technical solution:

[0006] A magnetocaloric module with a spiral-shaped thermally enhanced thin sheet includes:

[0007] A housing, wherein a sealed cavity is provided inside the housing;

[0008] A thermally conductive assembly, comprising a thermally conductive reinforcing sheet and thermally conductive rods, wherein the thermally conductive reinforcing sheet is wound into a spiral shape and axially installed in the sealed cavity, the thermally conductive reinforcing sheet is connected to the housing, and thermally conductive rods are provided at both ends of the thermally conductive reinforcing sheet along its axial direction, the thermally conductive rods being axially installed at both ends of the housing;

[0009] A magnetocaloric material, wherein the magnetocaloric material is disposed in the gaps of the thermally conductive reinforcing sheet;

[0010] The side wall of the housing is provided with an opening that connects to the sealed cavity.

[0011] Optionally, the housing includes an outer shell and end caps. The opening is provided on the side wall of the outer shell, and the end caps are provided at both ends of the outer shell to form the sealed cavity inside the outer shell. One end of the end cap is connected to the two ends of the thermally conductive reinforcing sheet along the axial direction of the sealed cavity, and the other end of the end cap is provided with the thermally conductive rod.

[0012] Optionally, the end cap includes an end cap body, a thin metal sheet bonded to the end cap body, and a heat-insulating layer bonded to the thin metal sheet. A slot is provided on the side of the end cap body near the sealed cavity. The slot extends on the end cap in a spiral shape corresponding to the thermally conductive reinforcing sheet. The cross-sectional shape of the slot corresponds to the end cross-sectional shape of the thermally conductive reinforcing sheet. The end of the thermally conductive reinforcing sheet is engaged in the slot. The heat-conducting rod penetrates the heat-insulating layer and is connected to the thin metal sheet.

[0013] Optionally, the end of the thermally conductive reinforcing sheet has a concave-convex structure, and the slot corresponds to a segmented vortex structure; or the end of the thermally conductive reinforcing sheet has a flat structure, and the slot corresponds to a complete vortex-shaped through groove.

[0014] Optionally, the thin metal sheet is provided with a plurality of elongated grooves extending radially along the thin metal sheet.

[0015] Optionally, the housing includes an outer shell and a non-metallic sealing strip. The outer shell has the sealed cavity inside, and the side wall of the outer shell has the opening. The two ends of the outer shell and the end of the thermally conductive reinforcing sheet are sealed by the non-metallic sealing strip, and the thermally conductive rod is connected to the end of the thermally conductive reinforcing sheet.

[0016] Optionally, a metal block is provided at one end of the heat-conducting rod and the heat-conducting enhancement sheet. A slot is provided on the side of the metal block away from the heat-conducting rod. The shape of the slot is adapted to the end shape of the heat-conducting enhancement sheet, and the slot is engaged with the end of the heat-conducting enhancement sheet.

[0017] Optionally, the outermost edge of the thermally enhanced sheet along the vortex direction does not obstruct the opening.

[0018] Optionally, the thermally enhanced sheet is provided with a number of slits.

[0019] Optionally, the material of the thermally conductive reinforcing sheet and the material of the thermally conductive rod are copper, and the material of the shell is stainless steel or glass fiber G10.

[0020] The beneficial effects of this invention are as follows: The magnetocaloric module with a vortex-shaped thermally conductive reinforcing sheet of this invention solves the problems of complex and difficult-to-operate wire threading, uneven arrangement, and large contact thermal resistance due to poor contact after the two ends are welded into a single copper rod in the prior art. The invention achieves the following benefits: replacing the heat bus formed by several thin metal wires with a vortex-shaped thermally conductive reinforcing sheet makes the arrangement of the heat bus more convenient, the assembly simpler, and the heat transfer within the magnetocaloric material more uniform; the vortex-shaped thermally conductive reinforcing sheet has several slits, which can increase the filling rate of the magnetocaloric material and facilitate the flow of the solution within the cavity during crystal growth; the magnetocaloric material divided by the thermally conductive reinforcing sheet also has a unified structure, which is more beneficial for single crystal growth; the two ends of the vortex are not closed, and no closed loop is formed, which can directly prevent eddy current heat from being generated along the vortex; the layered contact design at the ends reduces the thermal resistance of the magnetocaloric module while ensuring the sealing of both ends of the magnetocaloric module shell. Attached Figure Description

[0021] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of a magnetocaloric module with a spiral-shaped thermally enhanced sheet according to an embodiment of the present invention;

[0023] Figure 2 This is a cross-sectional view of the end cap of a magnetocaloric module with a spiral-shaped thermally enhanced sheet and a heat-conducting rod connected according to an embodiment of the present invention.

[0024] Figure 3 This is a partial structural schematic diagram of a magnetocaloric module with a spiral-shaped thermally conductive reinforcing sheet according to an embodiment of the present invention, when the thermally conductive reinforcing sheet is unfolded.

[0025] Figure 4 This is a top view of the end cap of a magnetocaloric module with a spiral thermally enhanced sheet according to an embodiment of the present invention, showing a complete spiral groove (left) and an incomplete spiral groove (right).

[0026] Figure 5 This is a top view of the thin metal sheet of a magnetocaloric module with a spiral-shaped thermally enhanced sheet according to an embodiment of the present invention;

[0027] Figure 6 This is an assembly diagram of the end of a magnetocaloric module with a spiral-shaped thermally enhanced sheet according to another embodiment of the present invention;

[0028] Figure 7 This is a schematic diagram of a magnetocaloric module with a spiral-shaped thermally conductive thin sheet in a refrigerator, according to an embodiment of the present invention.

[0029] Among them, 001, magnet; 002, magnetic shield; 1, shell; 2, heat-conducting component; 3, magnetocaloric material; 11, opening; 12, outer shell; 13, end cap; 14, non-metallic sealing strip; 21, heat-conducting reinforcing sheet; 22, heat-conducting rod; 131, end cap body; 132, thin metal sheet; 133, heat insulation layer; 134, slot; 135, slender groove; 211, slit; 221, metal block; 222, slot. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0031] The following is for reference Figure 1-6 A specific description will be given of a magnetocaloric module with a vortex-shaped thermally conductive thin sheet according to an embodiment of the present invention.

[0032] like Figure 1 As shown, a magnetocaloric module with a spiral-shaped thermally conductive reinforcing sheet according to an embodiment of the present invention includes a housing 1, a thermally conductive component 2, and a magnetocaloric material 3. The housing 1 has a sealed cavity. The thermally conductive component 2 includes a thermally conductive reinforcing sheet 21 and a thermally conductive rod 22. The thermally conductive reinforcing sheet 21 is wound into a spiral shape and axially installed in the sealed cavity. The thermally conductive reinforcing sheet 21 is connected to the housing 1. The thermally conductive rod 22 is provided at both ends of the thermally conductive reinforcing sheet 21 in the axial direction. The thermally conductive rod 22 is axially installed at both ends of the housing 1. The magnetocaloric material 3 is disposed in the gaps of the thermally conductive reinforcing sheet 21. An opening 11 communicating with the sealed cavity is provided on the side wall of the housing 1.

[0033] It should be noted that the shell 1 can be made of a material with low thermal conductivity and low eddy current heat. The vortex formed by the winding of the thermally conductive reinforcing sheet 21 is not limited to Archimedean spiral, Fermat spiral, equiangular spiral, hyperbolic spiral or irregular spiral. The thermally conductive rod 22 is used to connect the magnetocaloric material 3 to the external components of the magnetocaloric module. The opening 11 is a channel for solution inflow and gas outflow during the crystal growth process of the magnetocaloric material 3. After the magnetocaloric material 3 has completed growth in the gaps of the thermally conductive reinforcing sheet 21, the opening 11 can be sealed with an adhesive with low thermal conductivity.

[0034] Therefore, the magnetocaloric module with a vortex-shaped thermally conductive reinforcing sheet of the present invention solves the problems of complex and difficult-to-operate wire threading, uneven arrangement, and large contact thermal resistance due to poor contact after the two ends are welded into a single copper rod in the prior art. It achieves the following beneficial effects: the vortex-shaped thermally conductive reinforcing sheet 21 replaces the heat bus formed by several thin metal wires. The integral nature of the vortex-shaped thermally conductive reinforcing sheet 21 makes it more convenient to arrange the heat bus, simple to assemble, and the heat transfer in the magnetocaloric material 3 is more uniform. Several slits 211 are provided on the vortex-shaped thermally conductive reinforcing sheet 21, which can increase the filling rate of the magnetocaloric material 3 and facilitate the flow of the solution in the cavity during crystal growth. The magnetocaloric material 3 divided by the thermally conductive reinforcing sheet 21 also has integrality, which is more beneficial for the growth of single crystals. The two ends of the vortex are not closed and do not form a closed loop, which can directly avoid the generation of eddy current heat along the vortex. The layered contact design at the end makes the thermal resistance of the magnetocaloric module lower while ensuring the sealing of the two ends of the magnetocaloric module shell 12.

[0035] In one embodiment, the housing 1 includes an outer shell 12 and end caps 13. The outer shell 12 has an opening 11 on its side wall, and end caps 13 are provided at both ends of the outer shell 12 to form a sealed cavity within the outer shell 12. One end of each end cap 13 is connected to both ends of the thermally conductive reinforcing sheet 21 along the axial direction of the sealed cavity, and the other end of each end cap 13 is fitted with a heat-conducting rod 22. This provides an axial seal, facilitating the flow of solution within the sealed cavity during crystal growth.

[0036] like Figure 2As shown, in one embodiment, the end cap 13 includes an end cap body 131, a thin metal sheet 131 bonded to the end cap body 131, and a heat-insulating layer 133 bonded to the thin metal sheet 131. A slot 134 is provided on the side of the end cap body 131 near the sealed cavity. The slot 134 extends on the end cap 13 in a spiral shape corresponding to the thermally conductive reinforcing sheet 21. The cross-sectional shape of the slot 134 corresponds to the end cross-sectional shape of the thermally conductive reinforcing sheet 21. The end of the thermally conductive reinforcing sheet 21 is engaged in the slot 134. The heat-conducting rod 22 penetrates the heat-insulating layer 133 and is connected to the thin metal sheet 131.

[0037] This improves the overall sealing performance, prevents the solution from leaking out of the slot 134, establishes a heat transfer path, and enhances the axial heat conduction of the magnetothermal module.

[0038] like Figure 3-4 As shown, in one embodiment, the end of the thermally conductive reinforcing sheet 21 has a concave-convex structure, and the slot 134 corresponds to a segmented spiral structure; or the end of the thermally conductive reinforcing sheet 21 has a flat structure, and the slot 134 corresponds to a complete spiral-shaped through groove. Therefore, the thermally conductive reinforcing sheet 21 can be fixed while making assembly simpler and more convenient.

[0039] like Figure 5 As shown, in one embodiment, the thin metal sheet 131 is provided with a plurality of elongated grooves 135 extending radially along the thin metal sheet 131. This reduces eddy current heat generated on the thin metal sheet 131 and minimizes cooling loss.

[0040] like Figure 6 As shown, in another embodiment, the housing 1 includes an outer shell 12 and a non-metallic sealing strip 14. The outer shell 12 has the sealed cavity inside, and the side wall of the outer shell 12 has the opening 11. The two ends of the outer shell 12 and the end of the thermally conductive reinforcing sheet 21 are sealed by the non-metallic sealing strip 14. The thermally conductive rod 22 is connected to the end of the thermally conductive reinforcing sheet 21. This simplifies assembly.

[0041] In one embodiment, a metal block 221 is provided at the end where the heat-conducting rod 22 connects to the heat-conducting enhancement sheet 21. A slot 222 is formed on the side of the metal block 221 away from the heat-conducting rod 22. The shape of the slot 222 is adapted to the end shape of the heat-conducting enhancement sheet 21, and the slot 222 engages with the end of the heat-conducting enhancement sheet 21. This changes the heat transfer from line contact to surface contact, enhancing heat transfer to the outside without excessively increasing eddy current heat caused by changes in the magnetic field.

[0042] like Figure 1 As shown, in one embodiment, the outermost edge of the thermally enhanced sheet 21 along the vortex direction does not obstruct the opening 11. Therefore, the solution required for the growth of the magnetocaloric material 3 into the crystal can flow smoothly into the interior of the sealed cavity.

[0043] like Figure 3 As shown, in one embodiment, the thermally enhanced sheet 21 is provided with a plurality of slits 211.

[0044] It should be noted that, in order not to damage the integrity of the thermally conductive reinforcing sheet 21, the thermally conductive reinforcing sheet 21 is only partially wire-cut. This can reduce the eddy current heat generated by the change of magnetic field, and allow the solution for growing crystals to flow freely on the thermally conductive reinforcing sheet 21, filling the interior of the sealed cavity. It can also increase the filling rate of the magnetocaloric material 3, thereby improving the cooling performance of the magnetocaloric module.

[0045] In one embodiment, the materials of the thermally conductive reinforcing sheet 21 and the thermally conductive rod 22 are copper, and the material of the shell 1 is stainless steel or glass fiber G10. This allows for rapid heat transfer within the magnetocaloric material 3 while simultaneously creating an insulating environment.

[0046] by Figure 1-7 For example, an optional working process of the magnetocaloric module with a vortex-shaped thermally enhanced sheet in this invention is as follows:

[0047] The magnetothermal module is suspended and fixed on the axis of magnet 001 and magnetic shield 002 by external components. The magnetothermal material 3 releases heat when magnet 001 is energized and absorbs heat when magnet 001 is demagnetized. The magnetothermal material 3 achieves heat transfer to the outside world through the thermally conductive reinforced sheet 21 and the thermally conductive rod 22.

[0048] In the description of the embodiments of the present invention, it should be understood that the terms "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of the present invention.

[0049] Furthermore, the terms "first" and "another" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" or "several" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0050] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0051] In the description of this specification, references to terms such as "an embodiment," "an example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0052] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

[0053] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A magnetocaloric module with a spiral-shaped thermally enhanced thin sheet, characterized in that, include: A housing, wherein a sealed cavity is provided inside the housing; A thermally conductive assembly, comprising a thermally conductive reinforcing sheet and thermally conductive rods, wherein the thermally conductive reinforcing sheet is wound into a spiral shape and axially installed in the sealed cavity, the thermally conductive reinforcing sheet is connected to the housing, and thermally conductive rods are provided at both ends of the thermally conductive reinforcing sheet along its axial direction, the thermally conductive rods being axially installed at both ends of the housing; A magnetocaloric material, wherein the magnetocaloric material is disposed in the gaps of the thermally conductive reinforcing sheet; The side wall of the housing is provided with an opening that communicates with the sealed cavity; The housing includes an outer shell and a non-metallic sealing strip. The outer shell has a sealed cavity inside, and the side wall of the outer shell has the opening. The two ends of the outer shell and the end of the thermally conductive reinforcing sheet are sealed by the non-metallic sealing strip, and the thermally conductive rod is connected to the end of the thermally conductive reinforcing sheet.

2. The magnetocaloric module with a spiral-shaped thermally enhanced thin sheet according to claim 1, characterized in that, The housing includes an outer shell and end caps. The opening is provided on the side wall of the outer shell. The end caps are provided at both ends of the outer shell to form the sealed cavity inside the outer shell. One end of the end cap is connected to the two ends of the thermally conductive reinforcing sheet along the axial direction of the sealed cavity. The other end of the end cap is provided with the thermally conductive rod.

3. The magnetocaloric module with a spiral-shaped thermally enhanced thin sheet according to claim 2, characterized in that, The end cap includes an end cap body, a thin metal sheet bonded to the end cap body, and a heat-insulating layer bonded to the thin metal sheet. A slot is provided on the side of the end cap body near the sealed cavity. The slot extends on the end cap in a spiral shape corresponding to the thermally conductive reinforcing sheet. The cross-sectional shape of the slot corresponds to the end cross-sectional shape of the thermally conductive reinforcing sheet. The end of the thermally conductive reinforcing sheet is engaged in the slot. The heat-conducting rod penetrates the heat-insulating layer and is connected to the thin metal sheet.

4. The magnetocaloric module with a spiral-shaped thermally enhanced thin sheet according to claim 3, characterized in that, The end of the thermally conductive reinforcing sheet has a concave-convex structure, and the slot corresponds to a segmented vortex structure; or the end of the thermally conductive reinforcing sheet has a flat structure, and the slot corresponds to a complete vortex-shaped through groove.

5. A magnetocaloric module with a spiral-shaped thermally enhanced thin sheet according to claim 3, characterized in that, The thin metal sheet has several elongated grooves extending radially along the thin metal sheet.

6. The magnetocaloric module with a spiral-shaped thermally enhanced thin sheet according to claim 1, characterized in that, The end of the heat-conducting rod connected to the heat-conducting reinforcing sheet is provided with a metal block. A slot is opened on the side of the metal block away from the heat-conducting rod. The shape of the slot is adapted to the end shape of the heat-conducting reinforcing sheet, and the slot is engaged with the end of the heat-conducting reinforcing sheet.

7. The magnetocaloric module with a spiral-shaped thermally enhanced thin sheet according to claim 1, characterized in that, The outermost edge of the thermally conductive reinforced sheet along the vortex direction does not obstruct the opening.

8. The magnetocaloric module with a spiral-shaped thermally enhanced thin sheet according to claim 1, characterized in that, The thermally conductive enhanced sheet has several slits.

9. A magnetocaloric module with a spiral-shaped thermally enhanced thin sheet according to claim 1, characterized in that, The thermally conductive reinforcing sheet and the thermally conductive rod are made of copper, and the shell is made of stainless steel or glass fiber G10.

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