Interlayer supporting structure for low-temperature vacuum heat insulation container

Abstract

The invention relates to an interlayer supporting structure for a low-temperature vacuum heat insulation container, which comprises a first connecting piece fixedly arranged on an outer shell and a second connecting piece arranged on an inner shell, and the first connecting piece and the second connecting piece have a sleeving relation and can telescopically move relative to each other; the first connecting piece is in point contact with the second connecting piece in the axial direction and the radial direction of the first connecting piece, so that supporting force is formed in the axial direction and the radial direction, and meanwhile heat transfer between the outer shell and the inner shell is reduced. The first connecting piece and the second connecting piece are in point contact in the axial direction and the radial direction, so that the contact area between the supporting structure and the inner shell and the outer shell is greatly reduced, heat transfer caused by the supporting structure is remarkably reduced, heat leakage is reduced, and the service life of the supporting structure is prolonged. Through the design of the first connecting piece and the second connecting piece, the supporting structure can adapt to the thermal expansion difference generated by the temperature difference of the inner shell and the outer shell, damage or failure of the supporting structure caused by the thermal expansion difference can be prevented, the reliability of the container is improved, and the service life of the container is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of cryogenic containers, and in particular to a sandwich support structure for a cryogenic vacuum insulation container. Background Art

[0002] A vacuum insulated container is a device used to store cryogenic media. Its structural feature is that a certain distance is maintained between the inner and outer shells to form an interlayer. By evacuating the vacuum, the interlayer heat transfer is reduced, thereby maintaining the long-term storage requirements of the cryogenic medium in the inner shell. However, in the design of a vacuum insulated container, the design of the interlayer support structure is a key technical issue.

[0003] The vacuum insulation container is a double-layer structure. The interlayer space between the inner and outer shells is evacuated to a high vacuum state (usually less than 10 -3 Pa), so that the heat conduction and heat convection caused by the gas in the interlayer are reduced to a minimum, in order to maintain the long-term storage requirements of the low-temperature medium in the inner shell. The interlayer of the vacuum insulated container needs to fix the inner shell through a support structure. The support structure of the vacuum interlayer forms a hard connection between the inner and outer shells, and the temperature difference between the two ends is large. The heat leakage caused by the thermal bridge effect accounts for a large proportion of the total heat leakage of the container (usually >50%), and the local high temperature formed in the fixed area of ​​the inner shell support will produce point boiling, accelerate the flash evaporation of the internal low-temperature medium, and affect the pressure safety of the container. Improving the support structure, reducing the thermal bridge effect caused by the support structure, and reducing the heat leakage rate of the container are important ways to extend the lossless storage time of vacuum insulated containers.

[0004] According to Fourier's thermal conductivity theorem (Q = λAΔT / l, Q is the amount of heat leakage, λ is the thermal conductivity of the material, ΔT is the temperature difference between the inner and outer shells, and A and l are the cross-sectional area and length of the support, respectively), the main ways to reduce the thermal conductivity of the support are to use low thermal conductivity materials, reduce the cross-sectional area of ​​the support, and extend the length of the support. Among them, the commonly used low thermal conductivity materials need to be able to maintain a certain strength at the storage temperature, such as using glass fiber as the support structure material (CN201720527543.8, CN202021990638.1, CN201620945255.X), or adding low thermal conductivity gaskets at the contact point between the support and the shell wall (CN201922362321.7); reducing the cross-sectional area of ​​the support has a significant effect on reducing the heat transfer, such as using cylindrical supports instead of solid columns (CN2023107587 37.9, CN202121241962.8), and the contact part between the support and the outer shell wall is through a base or a ring with a small contact area (CN202123001196.0, CN201720527543.8), which can reduce the heat conduction area, reduce heat leakage, and improve the insulation performance of the container; extending the support length can increase the temperature gradient of the heat transfer process and reduce heat leakage, but the interlayer distance between the inner and outer shells is usually within a certain range, and the support needs to withstand a certain axial force. The implementation of the curved support is difficult, so this method has not been adopted.

[0005] The sandwich support structure of the vacuum insulation container needs to meet the requirements of providing sufficient support force and having low thermal conductivity at the same time, but the existing technology has not provided a good solution. In addition, the support is in hard contact with the outer shell wall. When storing low-temperature media, the shrinkage of the inner and outer tanks is different. After the liquid is filled, the shrinkage of the inner shell is greater than that of the outer shell, which will cause the support to separate from the outer shell wall or generate large tensile stress, making it impossible to effectively support.

[0006] In view of the above problems, the present invention proposes a sandwich support structure suitable for a low-temperature vacuum insulation container, which reduces heat leakage while providing sufficient support strength. Summary of the invention

[0007] In view of the deficiencies in the prior art, the present invention provides a sandwich support structure for a low-temperature vacuum insulated container, aiming to solve the problem that the existing support structure cannot simultaneously meet the requirements of sufficient supporting force and low thermal conductivity.

[0008] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: a sandwich support structure for a low-temperature vacuum insulated container, the support structure is arranged in the vacuum interlayer between the outer shell and the inner shell, the support structure includes: a first connecting member fixedly arranged on the outer shell and a second connecting member arranged on the inner shell, the first connecting member and the second connecting member have a telescopic relationship and can be telescopically moved relative to each other, the first connecting member forms point contact with the second connecting member in its axial and radial directions to form a supporting force in the axial and radial directions while reducing heat transfer between the outer shell and the inner shell.

[0009] Furthermore, an axial buffer mechanism and a radial buffer mechanism are provided between the first connecting member and the second connecting member. The first connecting member forms point contact with the second connecting member in the axial direction through the axial buffer mechanism and forms point contact with the second connecting member in the radial direction through the radial buffer mechanism.

[0010] Furthermore, the first connecting member is a sleeve fixedly arranged on the outer shell, and the second connecting member is a pillar fixedly arranged on the inner shell. The sleeve is coaxially arranged with the pillar and sleeved on the pillar.

[0011] Furthermore, the axial buffer mechanism includes a first sphere and a first elastic element arranged in the sleeve. The first sphere is connected to the sleeve through the first elastic element. Under the action of the first elastic element, the first sphere presses the end of the pillar to achieve point contact between the sleeve and the pillar in the axial direction.

[0012] Furthermore, there are multiple radial buffer mechanisms, and the multiple radial buffer mechanisms are evenly distributed around the circumference of the pillar.

[0013] Furthermore, the radial buffer mechanism includes a groove opened along the radial direction of the pillar from the side wall of the pillar to the inside of the pillar, a second elastic element and a second sphere arranged in the groove, the second sphere is connected to the groove through the second elastic element, a partial curved surface of the second sphere protrudes from the side wall of the pillar, and the second elastic element provides a pre-tightening force for the second sphere so that the second sphere presses the sleeve to achieve point contact between the pillar and the sleeve in the radial direction.

[0014] Further, the first elastic element is a first spring, and the second elastic element is a second spring.

[0015] Furthermore, the sleeve and the support are both made of low thermal conductivity material.

[0016] The present invention describes a sandwich support structure for a low-temperature vacuum insulated container, which has the following beneficial effects: point contact is formed in the axial and radial directions by the first connecting member and the second connecting member, which greatly reduces the contact area between the support structure and the inner and outer shells, thereby significantly reducing the heat transfer caused by the support structure and reducing the heat leakage. In addition, the first connecting member and the second connecting member have a telescopic relationship and can be telescopically moved relative to each other. This design enables the support structure to adapt to the thermal expansion difference between the inner and outer shells caused by the temperature difference, which helps to prevent damage or failure of the support structure due to the thermal expansion difference, thereby improving the reliability and service life of the container. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic diagram of a planar structure of a sandwich support structure according to an embodiment of the present invention;

[0018] Figure 2 is a partial enlarged view of an embodiment of the present invention;

[0019] Figure 3 is a schematic diagram of a second connecting member according to an embodiment of the present invention;

[0020] Figure 4 is a schematic diagram of a first connecting member according to an embodiment of the present invention;

[0021] Figure 5 5.5L vacuum insulation container of the present invention is a schematic diagram of the three-dimensional structure;

[0022] Figure 6 It is a schematic diagram of the temperature distribution of the existing cylindrical support structure;

[0023] Figure 7 Schematic diagram of the temperature distribution of the support structure according to an embodiment of the present invention.

[0024] Explanation of the reference numerals: 1. sleeve; 11. first elastic element; 12. first sphere; 2. pillar; 21. groove; 22. second elastic element; 23. second sphere; 3. outer shell; 4. inner shell; 5. interlayer. DETAILED DESCRIPTION

[0025] Typical embodiments that embody the features and advantages of the present invention will be described in detail in the following description. It should be understood that the present invention can have various changes in different embodiments without departing from the scope of the present invention, and the descriptions and illustrations therein are essentially used for illustration purposes rather than for limiting the present invention.

[0026] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0027] In order to further illustrate the principle and structure of the present invention, preferred embodiments of the present invention are now described in detail with reference to the accompanying drawings.

[0028] like Figure 1-7 As shown, an embodiment of the present invention provides a sandwich 5 support structure for a low-temperature vacuum insulated container, the support structure has multiple parts and all are arranged in the vacuum sandwich 5 between the outer shell 3 and the inner shell 4 of the insulated container, the support structure includes: a first connector fixedly arranged on the outer shell 3 and a second connector arranged on the inner shell 4, the second connector is sleeved on the first connector, the first connector forms a point contact with the second connector in its axial and radial directions, reducing the contact area between the first connector and the second connector, so as to form a supporting force in the axial and radial directions while reducing the heat transfer between the outer shell 3 and the inner shell 4. By reducing the heat transfer of the support structure, the present invention effectively improves the insulation performance of the low-temperature vacuum insulated container. This helps to maintain the stability of the low-temperature medium inside the container, reduce energy loss, and improve energy utilization efficiency.

[0029] Furthermore, the first connecting member is a sleeve 1 fixedly arranged on the outer shell 3, and the second connecting member is a pillar 2 fixedly arranged on the inner shell 4. The sleeve 1 is coaxially arranged with the pillar 2 and sleeved on the pillar 2. The sleeve 1 and the pillar 2 can move telescopically relative to each other. This design enables the support structure to adapt to the thermal expansion difference caused by the temperature difference between the inner and outer shells 3. This helps to prevent damage or failure of the support structure caused by the thermal expansion difference.

[0030] The above-mentioned sleeve 1 and support 2 are both made of low thermal conductivity material, and the low thermal conductivity material can be a common low thermal conductivity material.

[0031] Furthermore, an axial buffer mechanism and a radial buffer mechanism are provided between the first connector and the second connector. The axial buffer mechanism enables the first connector and the second connector to move relative to each other in the axial direction and maintain point contact. This design can adapt to the thermal expansion difference caused by the temperature difference between the inner and outer shells 3, and prevent excessive tensile stress or compressive stress caused by hard connection. The radial buffer mechanism ensures that in the radial direction, even if the inner and outer shells 3 are deformed by radial displacement due to temperature difference, the support structure can provide stable support force through radial point contact, while reducing heat transfer. By providing axial and radial buffer mechanisms, the support structure can better adapt to the thermal expansion difference and deformation of the inner and outer shells 3, thereby enhancing the structural stability of the entire container. The provision of the buffer mechanism can also effectively reduce the damage to the support structure caused by vibration or impact, and improve the vibration resistance and durability of the container.

[0032] Furthermore, the above-mentioned axial buffer mechanism includes a first sphere 12 and a first elastic element 11 arranged in the sleeve 1. The first sphere 12 is connected to the sleeve 1 through the first elastic element 11. Under the preload of the first elastic element 11, the first sphere 12 can press the end of the pillar 2. The first elastic element 11 is preferably a first spring. This design allows the sleeve 1 to form a point contact with the pillar 2 in the axial direction, thereby reducing the heat transferred through the support structure. Due to the presence of the first elastic element 11, when the inner shell 4 and the outer shell 3 produce a thermal expansion difference due to temperature changes, the first sphere 12 can be appropriately expanded and contracted under the action of the spring, thereby providing the necessary displacement compensation. This helps to maintain the stability and effectiveness of the support structure and prevent support failure or damage caused by thermal expansion differences.

[0033] Furthermore, there are multiple radial buffer mechanisms, and the multiple radial buffer mechanisms are evenly distributed around the pillar 2. The multiple radial buffer mechanisms are evenly distributed around the pillar 2, providing a more uniform support force for the pillar 2. This helps prevent the pillar 2 from being deformed or damaged due to uneven force, thereby enhancing the stability and reliability of the support structure.

[0034] Furthermore, the radial buffer mechanism includes a groove 21 radially extending from the side wall of the pillar 2 to the inside of the pillar 2, a second elastic element 22 and a second sphere 23 arranged in the groove 21, the second sphere 23 is connected to the groove 21 through the second elastic element 22, and partially protrudes from the side wall of the pillar 2 under the action of the pre-tightening force of the second elastic element 22, thereby pressing the sleeve 1 to achieve point contact between the pillar 2 and the sleeve 1 in the radial direction, and the second elastic element 22 is preferably a second spring. Due to the presence of the second elastic element 22, when the inner shell 4 and the outer shell 3 produce radial displacement due to temperature changes or other factors, the radial buffer mechanism can be appropriately expanded and adjusted. This helps to maintain a close fit and effective support between the pillar 2 and the sleeve 1, and prevent support failure or damage due to displacement differences.

[0035] In order to verify the performance of the structure of the present invention, thermal simulation calculations were performed on vacuum insulation containers with cylindrical direct-connected support structures and the support structure proposed by the present invention. Figure 5 As shown, the example container has a volume of 5.5L, the inner and outer shells are made of Al6061 material, the support structure is made of G10-CR material, the inner shell temperature is 20K, the outer shell temperature is 293K, and the interlayer vacuum is 10 -3 Pa. The temperature distribution of the heat transfer calculation results is as follows Figure 6 , Figure 7 Data analysis shows that the heat leakage of the cylindrical direct-connected support structure is 1.105W ( Figure 6 ), the heat leakage of the support structure proposed by the present invention is only 0.383W ( Figure 7 ), the heat leakage was reduced by 65.34%, and the thermal insulation effect was significant.

[0036] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any slight modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A sandwich support structure for a low-temperature vacuum insulation container, the support structure is arranged in a vacuum sandwich between an outer shell and an inner shell, characterized in that: The supporting structure includes: a first connecting member fixedly arranged on the outer shell and a second connecting member arranged on the inner shell. The first connecting member and the second connecting member are in a telescopic relationship with each other and can be telescopically moved relative to each other. The first connecting member forms point contact with the second connecting member in its axial and radial directions to form supporting force in the axial and radial directions while reducing heat transfer between the outer shell and the inner shell.

2. The sandwich support structure for a low-temperature vacuum insulation container according to claim 1, characterized in that: An axial buffer mechanism and a radial buffer mechanism are provided between the first connecting member and the second connecting member. The first connecting member forms a point contact with the second connecting member in the axial direction through the axial buffer mechanism and forms a point contact with the second connecting member in the radial direction through the radial buffer mechanism.

3. The sandwich support structure for a low-temperature vacuum insulation container according to claim 2, characterized in that: The first connecting member is a sleeve fixedly arranged on the outer shell, and the second connecting member is a pillar fixedly arranged on the inner shell. The sleeve is coaxially arranged with the pillar and sleeved on the pillar.

4. The sandwich support structure for a low-temperature vacuum insulation container according to claim 3, characterized in that: The axial buffer mechanism includes a first sphere and a first elastic element arranged in the sleeve. The first sphere is connected to the sleeve through the first elastic element. Under the action of the first elastic element, the first sphere presses the end of the pillar to achieve point contact between the sleeve and the pillar in the axial direction.

5. The sandwich support structure for a low-temperature vacuum insulation container according to any one of claims 3 or 4, characterized in that: There are multiple radial buffer mechanisms, and the multiple radial buffer mechanisms are evenly distributed around the circumference of the support.

6. The sandwich support structure for a low-temperature vacuum insulation container according to claim 5, characterized in that: The radial buffer mechanism includes a groove opened along the radial direction of the pillar from the side wall of the pillar to the inside of the pillar, a second elastic element and a second sphere arranged in the groove, the second sphere is connected to the groove through the second elastic element, a partial curved surface of the second sphere protrudes from the side wall of the pillar, and the second elastic element provides a pre-tightening force for the second sphere so that the second sphere presses the sleeve to achieve point contact between the pillar and the sleeve in the radial direction.

7. The sandwich support structure for a low-temperature vacuum insulation container according to claims 3 and 6, characterized in that: The first elastic element is a first spring, and the second elastic element is a second spring.

8. The sandwich support structure for a low-temperature vacuum insulation container according to claim 3, characterized in that: The sleeve and the support are made of low thermal conductivity material.

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