A low temperature sensor calibration device

Abstract

The present invention provides a low-temperature sensor calibration device, comprising a double-layer shock-absorbing structure located between a cold plate of a refrigerator and a temperature-averaging block, wherein the cold plate of the refrigerator is connected to a middle-layer flange through a shock-absorbing spring combination to form a first-layer shock-absorbing structure; the middle-layer flange and the upper-layer flange are connected through a bellows to form a second-layer shock-absorbing structure; the temperature-averaging block and the cold plate of the refrigerator are connected through a flexible connecting heat conducting belt to transfer the low temperature of the cold plate to the temperature-averaging block and be measured by a plurality of low-temperature sensors; by combining the double-layer shock-absorbing structure design and the flexible connecting heat conducting belt and other technical means, rapid and uniform measurement of the temperature field and effective isolation of vibration in a low-temperature calibration environment are achieved.

Description

Technical Field

[0001] The present invention relates to the field of cryogenic refrigeration technology, preferably to the field of cryogenic sensor calibration technology applied to the field of cryogenic refrigeration, and in particular to a cryogenic sensor calibration device. Background Art

[0002] Cryogenic sensors are widely used in fields that require precision measurement, including cryogenic medical equipment, quantum technology, aerospace, and large scientific facilities. The calibration of these sensors requires highly accurate temperature measurement, and the control of measurement accuracy and uncertainty is particularly important at extremely low temperatures (e.g., a few millikelvin to a few kelvins).

[0003] At present, the calibration of low-temperature sensors mainly relies on low-temperature refrigerators to generate low-temperature environments. However, the mechanical operation of the refrigerator will inevitably produce tiny vibrations, which will have a significant impact on the accuracy of the calibration process at extremely low temperatures, especially for measurements in the millikelvin range. In order to ensure the high-precision requirements of low-temperature calibration, it is usually necessary to design a special shock-absorbing device to reduce the vibration generated by the refrigerator to a negligible level. The current calibration of low-temperature sensors usually has no isolation mechanism between the refrigerator cold plate and the low-temperature sensor; or a spring gasket is installed to reduce the impact of vibration on the sensor, and the vibration generated by the refrigerator is absorbed by the spring gasket. This spring gasket isolation mechanism has a poor shock absorption effect in an extremely low temperature environment, and the uniformity of the low-temperature temperature field is difficult to ensure, resulting in uneven temperature, which in turn affects the accuracy of the sensor calibration.

[0004] Most of the shock absorbing devices in the prior art are used in high or normal temperature environments, while the designs of shock absorbing devices in low temperature, especially in the range of milliKelvin to several Kelvin, are relatively insufficient. This is because the material properties change at low temperatures, and it is difficult for the shock absorbing system to maintain a uniform temperature field at extremely low temperatures. Therefore, the industry needs a low-temperature sensor calibration device that can effectively reduce vibration at extremely low temperatures and provide a fast and uniform temperature field to ensure the accuracy and reliability of the calibration. Summary of the invention

[0005] The purpose of the present invention is to solve the technical problems discussed above, and thus provide a low-temperature sensor calibration device, which has a double-layer shock-absorbing structure and can quickly equalize the temperature, and can reduce shock and quickly equalize the temperature during the low-temperature sensor calibration process. The structure of the device is intended to minimize the transmission of vibrations generated by the operation of the refrigerator to the calibration device, so as to ensure that the calibration of the low-temperature sensor can meet the requirements of high accuracy and high stability in an extremely low temperature environment of millikelvin to several kelvins. The details are as follows:

[0006] A low-temperature sensor calibration device comprises a double-layer shock-absorbing structure located between a cold plate of a refrigerator and a temperature-averaging block, wherein the cold plate of the refrigerator is connected to a middle-layer flange by a combination of several evenly distributed shock-absorbing springs to form a first-layer shock-absorbing structure; the middle-layer flange and the upper-layer flange are connected by a bellows to form a second-layer shock-absorbing structure; the upper-layer flange is connected to the temperature-averaging block by a plurality of connecting studs to support the temperature-averaging block on the upper-layer flange, and a plurality of low-temperature sensors are evenly arranged on the temperature-averaging block to measure the temperature at different positions on the temperature-averaging block; the temperature-averaging block and the cold plate of the refrigerator are connected by a flexible connecting heat-conducting belt to transfer the low temperature of the cold plate to the temperature-averaging block and be measured by the plurality of low-temperature sensors.

[0007] Furthermore, in order to further enhance the stability of the structure, a multi-level structural balance and fixing system is designed between the upper flange and the middle flange. The upper flange and the middle flange are connected by multiple protective studs to maintain precise positioning and balancing, so that the upper flange remains balanced and reduces the transmission of vibration. The design of this balanced structure can ensure the stability of the calibration process in a low-temperature environment.

[0008] Furthermore, the plurality of protection studs pass through the middle flange, the shock absorbing spring assembly and the refrigerator cold plate and are fixed by the bottom loose nut to achieve the function of balance and additional shock absorption. This design further stabilizes the position of the upper flange through the physical structure, effectively reducing the slight deviation of the upper flange during the calibration process.

[0009] Furthermore, the multiple connecting studs adopt a hollow structure design, which reduces the heat conduction between the top temperature-averaging block and the upper flange below, ensuring that the temperature-averaging block can maintain a uniform temperature distribution and avoiding uneven temperature from affecting the calibration accuracy. This hollow structure of the connecting stud can effectively reduce heat conduction, prevent heat flow interference between the cold plate of the refrigerator and the upper uniform block, and ensure the stability and uniformity of the temperature field of the upper uniform block. Based on the traditional mechanical structure, this design achieves a technical breakthrough in temperature field uniformity through the heat insulation effect of the hollow structure of the connecting stud.

[0010] Furthermore, the connecting studs are hollow structural connecting studs made of stainless steel.

[0011] Furthermore, in order to quickly and evenly conduct low temperature, the flexible connection heat conducting belt between the top temperature equalizing block and the cold plate of the refrigerator adopts a high-purity copper rubber wire flexible heat conducting belt. This flexible heat conducting soft connection can quickly transfer the low temperature of the cold plate to the uniform block, realize rapid temperature uniformization, not only has high thermal conductivity, but also can adapt to the layout of sensors in different positions, thereby ensuring the temperature uniformity of the calibration environment, which is a unique innovation of the present invention in temperature uniformity.

[0012] The present invention realizes the rapid and uniform measurement of the temperature field and the effective isolation of vibration in the low-temperature calibration environment by combining multiple technical means such as the double-layer shock-absorbing structure design, the heat insulation design of the hollow structure connecting studs, and the high-purity copper rubber wire flexible heat-conducting belt. This comprehensive solution breaks through the technical bottleneck of the difficulty in balancing shock absorption and temperature field uniformity in traditional low-temperature calibration devices, and specifically produces the following technical effects:

[0013] 1. Double-layer shock-absorbing structure design

[0014] One of the core technologies of the present invention is to effectively isolate the vibration of the refrigerator through a double-layer shock-absorbing structure to reduce its interference with the calibration environment. The design of the double-layer shock-absorbing structure can not only effectively reduce the vibration transmission from the refrigerator, but also has good stability, greatly improving the reliability and stability of the shock-absorbing effect in a low-temperature environment.

[0015] 2. Hollow stud insulation design

[0016] In the connection between the uppermost temperature-averaging block and the upper flange, a stainless steel connecting stud with a hollow structure is used. This hollow structure can effectively reduce heat conduction, prevent heat flow interference between the refrigerator cold plate and the upper temperature-averaging block, and ensure the stability and uniformity of the temperature field of the temperature-averaging block. This design achieves a technical breakthrough in temperature field uniformity through the heat insulation effect of the hollow connecting stud on the basis of the traditional mechanical structure, which is another important innovation of the present invention.

[0017] 3. Rapid thermal conductivity design of high-purity copper rubber wire flexible thermal tape

[0018] In order to conduct low temperature quickly and evenly, a high-purity copper rubber wire flexible heat-conducting belt is used between the top uniform block and the cold plate of the refrigerator. This flexible heat-conducting belt can quickly transfer the low temperature of the cold plate to the uniform block, achieving rapid temperature uniformity. It not only has high thermal conductivity, but also can adapt to the layout of sensors in different positions, thereby ensuring the temperature uniformity of the calibration environment. It is a unique innovation of the present invention in temperature uniformity.

[0019] 4. Multi-level structural balance and fixed design

[0020] In order to further enhance the stability of the structure, the inventors designed a multi-level structural balance and fixing system between the upper flange and the middle flange, including a fixing method of multiple protective studs. Through the precise positioning and balancing of the protective studs, the upper flange maintains balance and reduces the transmission of vibration. The design of this balanced structure can ensure the stability of the calibration process in a low-temperature environment, which is one of the key supporting points of the technical solution of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It is obvious that the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0022] Figure 1 : The low temperature sensor calibration device of the present application.

[0023] Reference numerals:

[0024] 1-refrigeration machine cold plate; 2-temperature equalizing block; 3-shock-absorbing spring combination; 4-middle layer flange; 5-upper layer flange; 6-bellows; 7-connecting studs; 8-low temperature sensor; 9-flexible connecting belt; 10-protective studs; 11-bottom tightening nut. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings of the present invention. It is obvious that the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0026] Figure 1 The device shown is a rapid temperature-averaging low-temperature sensor calibration device with a double-layer shock-absorbing structure. The structure of the device is designed to minimize the transmission of vibrations generated during the operation of the refrigerator to the calibration device, so as to ensure that the calibration of the low-temperature sensor can achieve high accuracy and high stability in an extremely low temperature environment of millikelvin to several kelvins. Specifically, the calibration device includes a double-layer shock-absorbing structure located between the refrigerator cold plate 1 and the temperature-averaging block 2, wherein the refrigerator cold plate 1 is connected to the middle layer flange 4 through a plurality of evenly distributed shock-absorbing spring combinations 3 to form a first layer of shock-absorbing structure. The plurality of shock-absorbing spring combinations 3 can absorb and attenuate the low-frequency vibrations generated by the refrigerator cold plate 1 during operation, thereby reducing the impact of the vibrations on the upper structure.

[0027] The middle flange 4 and the upper flange 5 are connected by a bellows 6 to form a second layer of shock absorbing structure. The bellows 6 can effectively isolate the vibration transmission between the middle flange 4 and the upper flange 5, further reducing the impact of the refrigerator vibration on the calibration environment. At the same time, the elastic structure of the bellows 6 helps to maintain the balance of the upper flange 5 and ensure the stability of the calibration environment.

[0028] The upper flange 5 is connected to the temperature-averaging block 2 through a plurality of connecting studs 7 to support the temperature-averaging block 2 on the upper flange 5. The plurality of connecting studs 7 are designed with a hollow structure, which reduces the heat conduction between the uppermost temperature-averaging block 2 and the upper flange 5 below, ensuring that the temperature-averaging block 2 can maintain a uniform temperature distribution and avoid uneven temperature affecting the calibration accuracy. The plurality of connecting studs 7 with such a hollow structure can effectively reduce heat conduction, prevent heat flow interference between the cold plate 1 of the refrigerator and the temperature-averaging block 2, and ensure the stability and uniformity of the temperature field of the temperature-averaging block 2. Based on the traditional mechanical structure, this design achieves a technological breakthrough in the uniformity of the temperature field through the heat insulation effect of the plurality of connecting studs 7 with a hollow structure. Furthermore, the plurality of connecting studs 7 are hollow structure connecting studs made of stainless steel.

[0029] A plurality of low-temperature sensors 8 are evenly arranged on the temperature-averaging block 2 to measure the temperature at different positions on the temperature-averaging block 2, ensuring that all low-temperature sensors 8 are in a consistent low-temperature environment, thereby improving the accuracy of calibration. The temperature-averaging block 2 is connected to the cold plate 1 of the refrigerator by a flexible connecting heat conducting belt 9 to transfer the low temperature of the cold plate 1 of the refrigerator to the temperature-averaging block 2 and be measured by the plurality of low-temperature sensors 8.

[0030] In order to further enhance the stability of the structure, a multi-level structural balance and fixing system is designed between the upper flange 5 and the middle flange 4. The upper flange 5 and the middle flange 4 are connected by multiple protective studs 10 to maintain precise positioning and balancing, so that the upper flange 5 remains balanced and reduces the transmission of vibration. The design of this balanced structure can ensure the stability of the calibration process in a low-temperature environment.

[0031] Multiple protective studs 10 are fixed to the upper flange 5, and can further pass through the middle flange 4, the shock-absorbing spring assembly 3, and the refrigerator cold plate 1, and are fixed by the bottom loose nut 11 to play a role of balance and additional shock absorption. This design further stabilizes the position of the upper flange 5 through the physical structure, effectively reducing the slight deviation of the upper flange 5 during the calibration process.

[0032] In order to conduct low temperature quickly and evenly, the flexible connecting heat conducting belt 9 between the uppermost temperature equalizing block 2 and the refrigerator cold plate 1 adopts a high-purity copper rubber wire flexible heat conducting belt. This flexible heat conducting belt can quickly transfer the low temperature of the refrigerator cold plate 1 to the temperature equalizing block 2, realize rapid temperature uniformity, avoid the phenomenon of uneven temperature field in traditional mechanical seismic isolation and suspension shock absorption schemes, not only has high thermal conductivity, but also can adapt to the layout of low-temperature sensors in different positions, thereby ensuring the temperature uniformity of the calibration environment, which is a unique innovation of the present invention in temperature uniformity.

[0033] The above is a detailed introduction to a rapid temperature equalization low-temperature sensor calibration device with a double-layer shock-absorbing structure provided by the present invention. This article uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. For ordinary technicians in this field, the technical solution of the present invention is not limited to the solution defined by the specific implementation method. The technical solutions formed by other changes that can be obviously realized according to the common technical knowledge in this field are all within the protection scope of the present invention.

Claims

1. A low-temperature sensor calibration device, comprising a double-layer shock-absorbing structure located between a refrigerator cold plate and a temperature-averaging block, wherein the refrigerator cold plate is connected to an intermediate flange by a combination of several evenly distributed shock-absorbing springs to form a first-layer shock-absorbing structure; the intermediate flange and the upper flange are connected by a bellows to form a second-layer shock-absorbing structure; the upper flange is connected to the temperature-averaging block by a plurality of connecting studs to support the temperature-averaging block on the upper flange, and a plurality of low-temperature sensors are evenly arranged on the temperature-averaging block to measure the temperature at different positions on the temperature-averaging block; the temperature-averaging block and the refrigerator cold plate are connected by a flexible The thermal conductive tape is connected to transfer the low temperature of the cold plate to the temperature equalizing block and is measured by multiple low-temperature sensors; the multiple connecting studs are designed with a hollow structure to reduce heat conduction between the temperature equalizing block and the upper flange, prevent heat flow interference between the cold plate of the refrigerator and the upper temperature equalizing block, ensure that the temperature equalizing block can maintain a uniform temperature distribution, and avoid uneven temperature affecting the calibration accuracy; the upper flange and the middle flange are connected by multiple protective studs to maintain precise positioning and balance, so that the upper flange remains balanced and reduces the transmission of vibration, ensuring the stability of the calibration process in a low-temperature environment.

2. A low-temperature sensor calibration device as described in claim 1, wherein the multiple protective studs further pass through the middle layer flange, the shock-absorbing spring combination and the refrigerator cold plate and are fixed by the bottom tightening nuts to achieve a balancing and additional shock-absorbing effect.

3. The low-temperature sensor calibration device as described in claim 1, wherein the plurality of connecting studs are hollow structure connecting studs made of stainless steel.

4. The low temperature sensor calibration device according to any one of claims 1 to 3, wherein: In order to conduct low temperature quickly and evenly, the flexible connecting heat conducting belt between the temperature equalizing block and the cold plate of the refrigerator adopts a high-purity copper rubber wire flexible heat conducting belt.

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