A cryogenic self-locking thermal coupling connection device and assembly method

Abstract

The application discloses a kind of extremely low temperature self-locking thermal coupling connecting device and assembling method, including low temperature receiving module, extremely low temperature self-locking thermal coupling base. Low temperature receiving module includes low temperature receiving module upper installation top disc, low temperature receiving module cold conducting shell and low temperature receiving core function component;Extremely low temperature self-locking thermal coupling base includes self-locking low temperature thermocouple clamp, buffer heat insulation bushing and extremely low temperature heat conducting base, extremely low temperature heat conducting base is set installation guide positioning dowel and blind insertion combination matched port, self-locking low temperature thermocouple clamp is set groove. When the device is cooled to 77K and below extremely low temperature environment, the shrinkage of self-locking low temperature thermocouple clamp is greater than the low temperature receiving module cold conducting shell, and the interference clamping force is automatically generated to complete self-locking. The application does not need additional fastener, and is easy to disassemble and assemble. The heat conduction interface contact thermal resistance is low. The buffer bushing can buffer alternating stress and protect the elastic structure. The service life is longer. It is suitable for large-scale low-temperature receiving array long-term cold and hot cycle use.

Description

Technical Field

[0001] The present invention belongs to the technical field of high-sensitivity cryogenic receiving, and specifically relates to an ultra-low temperature self-locking thermal coupling connection device and an assembly method thereof. Background Art

[0002] In ultra-low temperature receiving systems supporting large-scale radio telescopes, deep space exploration and other equipment, the core functional modules of the low-noise receiving channel mainly include devices such as superconducting filters, low-noise amplifiers, and cryogenic hybrid integrated circuits. The above devices must operate stably in an ultra-low temperature environment of 77K and below to ensure the low-noise performance required for the whole machine to detect weak radio frequency signals. For large-scale array refrigerated receiving systems such as phased array feeds (PAF), the connection structure of the cryogenic module needs to meet two core requirements at the same time: first, the reliability of mechanical connection, the module shall not be loosened or displaced under the working conditions of cryogenic thermal cycles and equipment vibration, so as to avoid the degradation of array accuracy and the damage of system detection sensitivity; second, excellent thermal conductivity, which needs to quickly conduct the heat generated by the operation of the module to the cold source, so as to stably maintain the low-temperature working environment of the devices.

[0003] At present, the mainstream methods for realizing the mechanical fixation and thermal conduction interconnection between the cryogenic module and the cold source in engineering are divided into four types: bolt fastening, welding, cryogenic adhesive bonding, and cold strip interconnection, and each type of scheme has inherent shortcomings: first, the bolt fastening method is prone to problems such as material brittle fracture and thermal stress relaxation after long-term cryogenic operation, resulting in loosening of the fastening points, and a large number of bolts in the array system will also greatly increase the difficulty of assembly and subsequent maintenance; second, the welding process has a complicated implementation procedure, the residual stress generated by welding is easy to damage precision core components such as superconductors and cryogenic amplifiers, and the modules cannot be disassembled and replaced independently after welding, resulting in poor maintainability; third, the interface contact thermal resistance of the cryogenic adhesive structure is high, the heat transfer efficiency is low, which cannot meet the strict thermal management indicators of the ultra-low temperature system, and the adhesive layer is prone to embrittlement and delamination at low temperatures, losing the fixing and thermal conductivity capabilities; fourth, the assembly process of cold strip interconnection is cumbersome, and the cold strips inside the array are arranged in a disorderly manner, which is not conducive to the engineering mass implementation of large-scale cryogenic array receiving systems. In addition, the existing ordinary clamp clamping structure only relies on the pre-tightening force at room temperature to achieve holding and fixing, and the conventional clamp lacks an elastic slot and a buffer bushing structure, so stress fatigue is easy to occur at the tooth root during repeated thermal cycles and disassembly and assembly processes, resulting in a short service life.

[0004] Patent publication number CN223897560U discloses a rapid testing fixture suitable for cryogenic circulators. This fixture uses an aluminum frame-type Dewar, an oxygen-free copper thermal pad, and multiple sets of sealed RF connectors to build a vacuum cryogenic testing chamber. It can quickly clamp cryogenic microwave devices and achieve a sealed cryogenic environment in the chamber by relying on an external vacuum pipeline. This can shorten the single test cycle of cryogenic devices and improve the efficiency of iterative testing of cryogenic device samples. However, it is only designed for short-term performance testing of discrete devices and only has the basic functions of fixing the test device and conducting low-temperature heat. It cannot achieve integrated self-locking assembly and connection of cryogenic modules and cold sources. It has the defects of relying on repeated tightening of screws for assembly, easy loosening during cold and hot cycles, and high thermal contact resistance. It is difficult to simultaneously achieve mechanical self-locking fastening and low-resistance, high-efficiency, and continuous thermal coupling transmission at extremely low temperatures.

[0005] In summary, existing technologies lack an integrated connection device that can simultaneously achieve ultra-low temperature self-locking mechanical fixation and facilitate rapid disassembly and maintenance of the array. Summary of the Invention

[0006] The problem this invention aims to solve is that there is currently a lack of a connection device that can simultaneously achieve self-locking mechanical fixation, high-efficiency heat conduction at extremely low temperatures of 77K and below, and rapid disassembly and maintenance.

[0007] The present invention solves the above-mentioned technical problems through the following technical means: A cryogenic self-locking thermal coupling connection device includes a cryogenic receiving module and a cryogenic self-locking thermal coupling base. The low-temperature receiving module includes a mounting plate on the low-temperature receiving module, a cooling shell for the low-temperature receiving module, and a core functional component for low-temperature receiving. The core functional component for low-temperature receiving is encapsulated and fixed inside the cooling shell for the low-temperature receiving module, and the mounting plate on the low-temperature receiving module is fixed to the upper end of the cooling shell for the low-temperature receiving module. The ultra-low temperature self-locking thermal coupling base includes a self-locking low-temperature thermocouple clip, a buffer insulation bushing, and an ultra-low temperature thermally conductive base. The ultra-low temperature thermally conductive base and the self-locking low-temperature thermocouple clip are fixed together to the ultra-low temperature cold source mounting surface. The self-locking low-temperature thermocouple clip is a tubular structure, including multiple elastic plates. The elastic plates are evenly distributed in a ring to form an elastic encircling structure. Slots are provided between adjacent elastic plates, and the slots have a consistent width. The buffer insulation bushing is arranged outside the upper open ring portion of the elastic plates of the self-locking low-temperature thermocouple clip.

[0008] The system adopts a modular design with separate cryogenic receiving module and thermal coupling base, allowing for individual processing, assembly, and maintenance at room temperature. It is suitable for batch assembly and maintenance of large-scale array cooling receiving systems. The base is directly fixed to the ultra-low temperature cold source, resulting in a short and continuous heat transfer path. Combined with the subsequent self-locking structure based on the thermal shrinkage difference of dissimilar materials, it can overcome multiple pain points of traditional bolts, such as low-temperature loosening, easy damage to components during welding, high thermal resistance of adhesives, and cumbersome cold-band assembly. It meets the dual requirements of low-temperature mechanical fastening reliability and ultra-low thermal contact resistance. The uniformly distributed circumferentially slotted elastic sheet structure provides uniform circumferential clamping force, fully closes to reduce thermal resistance, and controls the slot size to avoid plastic deformation of the elastic sheet, thereby improving reliability.

[0009] Preferably, the self-locking cryogenic thermocouple clamp is made of aluminum alloy.

[0010] Aluminum alloys have a large shrinkage at low temperatures, which creates a shrinkage difference with copper parts. After cooling, an interference clamping force is automatically generated, achieving a low-temperature self-locking effect.

[0011] Preferably, the cold-conducting shell of the low-temperature receiving module, the ultra-low-temperature heat-conducting base, and the shell of the core functional component of the low-temperature receiving module are all made of oxygen-free copper.

[0012] All heat-conducting core components are made of oxygen-free copper, which has excellent thermal conductivity, quickly dissipates heat from the module, and maintains a low-temperature working environment.

[0013] Preferably, the buffer insulation bushing is made of nylon or epoxy glass, and the buffer insulation bushing has a mounting and fixing through hole and a mounting and fixing threaded hole, and is locked and fixed to the upper end of the open ring part of the self-locking low temperature thermocouple clip elastic sheet by screws.

[0014] Nylon or epoxy glass bushings buffer stress, balance clamping force, limit maximum deformation of elastic sheet, alleviate stress concentration during thermal cycles, and extend the service life of thermocouple clamps; at the same time, they can ensure the limiting clamping effect of self-locking device at room temperature.

[0015] Preferably, the ultra-low temperature heat-conducting base is provided with mounting guide positioning pins, and the cooling shell of the low temperature receiving module has positioning pin holes that match the mounting guide positioning pins. The low temperature receiving module achieves blind insertion and docking with the ultra-low temperature self-locking thermal coupling base through the mounting guide positioning pins.

[0016] Preferably, the low-temperature receiving core functional component is provided with a signal output port at its bottom, and the ultra-low temperature heat-conducting base is provided with a blind-plug combination matching port; the signal output port and the blind-plug combination matching port are plugged in and matched, and the signal and power supply interconnection is completed synchronously after docking.

[0017] The blind-plug port design allows for simultaneous insertion and removal of RF and power supply connections, eliminating the need for separate wiring and significantly improving the efficiency of array module assembly and disassembly.

[0018] Preferably, one end of the installation guide positioning pin is tightly fitted and fixed to the ultra-low temperature heat-conducting base, and the other end is loosely fitted to the positioning pin hole of the low temperature receiving module's cooling shell.

[0019] Preferably, the low-temperature shrinkage rate of the installation guide positioning pin is less than the shrinkage amount of the positioning pin hole.

[0020] The pin shrinks less at low temperatures, and after cooling, the pin fits more tightly with the pin hole, further enhancing the overall locking and limiting effect.

[0021] Preferably, the mounting surface of the top plate on the low-temperature receiving module and the fixing surface of the low-temperature receiving module's cooling shell serve as the force-bearing panel for manual insertion and removal of the low-temperature receiving module.

[0022] This invention also discloses an installation method using the aforementioned cryogenic self-locking thermal coupling connection device, comprising the following steps: S1. Assemble the cryogenic receiving module: Fix the core functional components of the cryogenic receiving module to the inner wall of the cryogenic receiving module's cooling shell, and then assemble the top plate on the cryogenic receiving module. S2. Assemble the ultra-low temperature self-locking thermal coupling base: Fix the buffer insulation bushing to the upper end of the self-locking low temperature thermocouple clip, and fit the self-locking low temperature thermocouple clip on the outside of the ultra-low temperature thermal conductive base. Fix the whole assembly to the ultra-low temperature cold source. S3, Blind mating: The top plate is installed on the handheld low temperature receiver module, and the base is inserted by relying on the installation guide positioning pin to realize the blind mating of the signal output port and the matching port of the blind mating combination; S4. Low-temperature self-locking: When the device is cooled to an extremely low temperature environment of 77K and below, the shrinkage of the self-locking low-temperature thermocouple clamp is greater than that of the inner copper component, generating an interference clamping force to automatically tighten the low-temperature receiving module's cooling shell, simultaneously achieving mechanical locking and efficient heat conduction.

[0023] The advantages of this invention are: (1) Differential thermal shrinkage self-locking mechanism: Relying on the difference in the coefficient of thermal expansion between aluminum alloy thermocouple clip and oxygen-free copper thermal conductive shell and base at low temperature, when the device is cooled to an extremely low temperature environment of 77K and below, the aluminum thermocouple clip shrinks more, automatically generating a uniform and stable interference clamping force. No additional fasteners are needed to maintain the clamping throughout the process, effectively solving the problems of thermal stress relaxation and material brittle fracture and loosening under low temperature in traditional bolt fastening. There is no risk of residual stress introduced by welding damaging precision core components such as superconductors and low temperature amplifiers. At the same time, the low temperature shrinkage rate of stainless steel positioning pin is less than that of pin hole. After low temperature, the pin and pin hole are further tightened together, and the double limit prevents the module from shifting. There is no loosening or shifting under long-term hot and cold cycle conditions, ensuring the antenna array receiving accuracy and system detection sensitivity. (2) Easy assembly and maintenance, suitable for large-scale array engineering: This invention divides the equipment into two separate modules: a low-temperature receiving module and an ultra-low temperature self-locking thermal coupling base. The parts can be processed, tested and replaced separately, and there is no need to disassemble the cooling cavity as a whole during maintenance. With the positioning pin guide + RF power supply integrated blind plug port, mechanical positioning, signal and power supply interconnection can be completed simultaneously with a single plug-in and unplug, eliminating the cumbersome procedures of traditional solutions such as multi-point bolt tightening, cold-wire wiring and separate wiring; (3) Full-area tight fit and low resistance heat conduction: The core components of low temperature heat conduction are all made of high thermal conductivity oxygen-free copper material. The cold source, heat conduction base and module cold conduction shell form a continuous heat conduction path; the uniform interference pressure generated by low temperature self-locking makes each heat conduction contact surface fit completely, greatly reducing the interface contact thermal resistance. The heat generated by the module can be quickly and evenly transferred to the cold source. (4) Long service life of the device: The self-locking low temperature thermocouple clamp adopts a uniformly distributed comb-shaped slotted elastic structure, with uniform circumferential clamping force to avoid local stress concentration; the upper end is equipped with a nylon or epoxy glass buffer insulation bushing, which provides uniform radial prestress for the elastic clamp, making the clamping force stable and balanced throughout the process, and limits the maximum elastic deformation of the elastic sheet to prevent plastic fatigue fracture of the comb teeth during disassembly and assembly; the bushing can buffer the alternating stress generated by the cold and hot cycle, absorb the stress peak caused by interference clamping, greatly alleviate the fatigue wear of the aluminum thermocouple clamp under long-term high and low temperature alternating use, and significantly improve the ultra-low temperature cycle service life and long-term operation stability of the entire connection device. Attached Figure Description

[0024] Figure 1 This is a three-dimensional structural schematic diagram of an ultra-low temperature self-locking thermal coupling connection device according to Embodiment 1 of the present invention; Figure 2 This is an exploded schematic diagram of an ultra-low temperature self-locking thermal coupling connection device according to Embodiment 1 of the present invention; Figure 3 This is a cross-sectional view of an ultra-low temperature self-locking thermal coupling connection device according to Embodiment 1 of the present invention; Figure 4 This is a schematic diagram of the self-locking low-temperature thermal coupling clip structure of an ultra-low temperature self-locking thermal coupling connection device according to Embodiment 1 of the present invention; Figure 5 This is a top view of a self-locking low-temperature thermal coupling clamp of an ultra-low temperature self-locking thermal coupling connection device according to Embodiment 1 of the present invention; Figure 6 This is a schematic diagram of the buffer insulation bushing structure of an ultra-low temperature self-locking thermal coupling connection device according to Embodiment 1 of the present invention.

[0025] In the picture: 1. Low-temperature receiving module; 11. Mounting plate on the low-temperature receiving module; 12. Cooling housing of the low-temperature receiving module; 13. Core functional components of the low-temperature receiver; 2. Ultra-low temperature self-locking thermal coupling base; 21. Self-locking low temperature thermocouple clip; 22. Buffer insulation bushing; 23. Ultra-low temperature thermal conductive base; 3. Signal port; 31. Signal input port; 32. Signal output port; 4. Blind mating assembly; 41. Blind mating port; 42. Blind mating combination port; 5. Install guide positioning pins; 6. Locating pin holes; 7. Install and fix the threaded holes; 8. Install and fix the through holes; 9. Grooving. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] Example 1: This invention provides an ultra-low temperature self-locking thermal coupling connection device, which includes a low temperature receiving module 1, an ultra-low temperature self-locking thermal coupling base 2, and is also equipped with a signal port 3, a blind mating assembly 4, a mounting guide positioning pin 5, a positioning pin hole 6, a mounting fixing threaded hole 7, a mounting fixing through hole 8, and a slot 9. Specifically, the low temperature receiving module 1 includes a mounting top plate 11, a low temperature receiving module cooling shell 12, and a low temperature receiving core functional component 13; the ultra-low temperature self-locking thermal coupling base 2 includes a self-locking low temperature thermocouple clip 21, a buffer insulation bushing 22, and an ultra-low temperature thermally conductive base 23; the self-locking low temperature thermocouple clip 21 has a slot 9, the buffer insulation bushing 22 has a mounting fixing threaded hole 7 and a mounting fixing through hole 8; the low temperature receiving module cooling shell 12 has a positioning pin hole 6, the ultra-low temperature thermally conductive base 23 is equipped with a mounting guide positioning pin 5, and also carries a blind mating assembly 4, which can be blindly mated with the signal port 3 of the low temperature receiving core functional component 13.

[0028] See Figures 1-3The low-temperature receiving module 1 is the main functional unit of the whole device to realize low-noise signal reception. As an independent pluggable component, it can be blindly assembled with the ultra-low temperature self-locking thermal coupling base 2. The internal components include the mounting plate 11 on the low-temperature receiving module, the cooling shell 12 of the low-temperature receiving module, and the core functional components of the low-temperature receiving module 13.

[0029] For details, please refer to Figures 1-3 The top plate 11 mounted on the cryogenic receiving module is the top operating and supporting component of the cryogenic receiving module 1. It is made of Al6061 aluminum alloy (i.e., 6-series aluminum-magnesium-silicon Al-Mg-Si heat-treatable strengthened aluminum alloy; this embodiment uses this alloy, but adjustments can be made according to specific needs). It has a flat plate structure and is fixed to the upper surface of the cryogenic receiving module's cooling housing 12 by screws (or other fixing methods). Together with the cryogenic receiving module's cooling housing 12 and the cryogenic receiving core functional component 13, it forms the complete cryogenic receiving module 1. The top plate 11 is securely connected to the cryogenic receiving module's cooling housing 12, forming a completely enclosed upper structure of the module. This provides top-limiting protection for the internal cryogenic receiving core functional component 13, preventing shaking or damage to internal components during transport and insertion / removal. When assembling or disassembling the module, the operator holds the top plate 11 to complete the insertion and removal operation. All external force is borne by the top plate and will not directly affect the precision heat-conducting and RF structures such as the cryogenic receiving module's cooling shell 12 and signal port 3. This prevents interface deformation and scratches on the heat-conducting contact surface caused by insertion and removal force, protecting the module's cooling and RF transmission performance. The use of lightweight aluminum alloy does not add extra weight to the overall module and reduces the load pressure of large-scale array stacking assembly. At the same time, the low-temperature shrinkage of aluminum alloy differs from that of the inner oxygen-free copper cooling shell, but it only serves as a top operating component and does not participate in the main thermal path, thus not interfering with the overall self-locking and thermal coupling effect of the device.

[0030] For details, please refer to Figures 1-3 The cryogenic receiving module's cooling housing 12 is the core heat-conducting component of the cryogenic receiving module 1. It is an integrally milled oxygen-free copper component, which is assembled and fitted with the mounting plate 11 and the core functional component 13 of the cryogenic receiving module. At the same time, its outer wall is in contact with the inner wall of the self-locking cryogenic thermocouple clip 21. Because the whole is made of oxygen-free copper, it has an extremely high thermal conductivity, which can quickly conduct the heat generated by the operation of the core functional component 13 of the cryogenic receiving module outward. The coefficient of linear expansion of oxygen-free copper is less than that of Al6061 aluminum alloy, which can form a thermal contraction difference with the self-locking cryogenic thermocouple clip 21. After cooling, it is held tightly by the elastic clip, reducing the interface contact thermal resistance.

[0031] The cryogenic receiving module's cooling housing 12 has a pre-reserved mounting plane inside. The core functional component 13 of the cryogenic receiving module is fixed to this plane by screws (or other fixing methods), allowing the heat generated by the component to directly contact the housing over a large area, reducing heat transfer gaps. The signal ports 3 of the core functional component 13 are located on the corresponding side wall of the housing, ensuring accurate port alignment during blind mating. Threaded holes are provided on the upper surface of the housing for locking and fixing the mounting plate 11 on the cryogenic receiving module, achieving overall enclosed protection for the module.

[0032] See Figures 1-3 The low-temperature receiving module's cooling housing 12 also has positioning pin holes 6 on its side wall. During assembly, these holes fit with the installation guide positioning pins 5, enabling blind insertion of the low-temperature receiving module 1 into the ultra-low temperature self-locking thermal coupling base 2, reducing the difficulty of assembly alignment. The low-temperature receiving module's cooling housing 12 can be smoothly inserted into the self-locking low-temperature thermocouple clip 21 at room temperature. When the temperature drops to 77K and below, the self-locking low-temperature thermocouple clip 21 shrinks more, forming a uniform interference fit on the outer wall, ensuring complete contact of the thermally conductive surfaces and significantly reducing thermal resistance.

[0033] For details, please refer to Figures 1-3 The cryogenic receiving core functional component 13 is the core functional device of the cryogenic receiving module 1 for low-noise signal reception, amplification, and filtering. It is fixed inside the cryogenic receiving module's cooling housing 12 and serves as the main signal processing component of the entire cryogenic receiving system, adaptable to operating temperatures of 77K and below. This component utilizes various cryogenic microwave receiving components such as superconducting filters, cryogenic low-noise amplifiers, and cryogenic hybrid integrated circuit modules, and is a standard core component of radio telescopes and deep space exploration array receivers. The cryogenic receiving core functional component 13 has its own metal encapsulation housing, which is also made of oxygen-free copper to ensure a tight fit and heat conduction with the cryogenic receiving module's cooling housing 12.

[0034] The cryogenic receiver core functional component 13 is installed on a dedicated mounting plane inside the cryogenic receiver module's cooling housing 12 via screw fastening (or other fixing methods). This mounting plane is also the plane where the signal port 3 is located, achieving large-area surface contact between the device and the cooling housing 12. A flexible, high thermal conductivity interface material is used between the cryogenic receiver core functional component 13 and the inner shell of the cryogenic receiver module's cooling housing 12 to achieve low thermal resistance mounting. During operation, the heat generated by the device can be quickly transferred to the oxygen-free copper housing, and then conducted to the cold source by the ultra-low temperature self-locking thermal coupling base 2, stabilizing the device's low-temperature operating conditions. The signal port 3 is integrated on the outside of the cryogenic receiver core functional component 13, and the port position is precisely aligned with the blind mating assembly 4 on the ultra-low temperature thermally conductive base 23. After the cryogenic receiver module 1 completes the blind mating assembly guided by the installation guide positioning pin 5, the signal port 3 and the blind mating assembly 4 automatically connect and conduct, completing the RF signal transmission and power supply line connection in one go, eliminating the need for separate wiring operations and significantly improving the array module's assembly and disassembly efficiency.

[0035] See Figures 1-3 The ultra-low temperature self-locking thermal coupling base 2 is the basic support unit for the entire device to connect with the ultra-low temperature cold source and realize the self-locking clamping and efficient heat conduction of the low temperature receiving module 1. It is fixed on the cold source mounting surface in the temperature range of 77K and below. It is assembled from three parts: self-locking low temperature thermocouple clip 21, buffer insulation bushing 22, and ultra-low temperature heat conduction base 23. It can be blindly matched with the low temperature receiving module 1 by installing guide positioning pins 5, and simultaneously realize mechanical locking, radio frequency power supply interconnection and continuous cooling.

[0036] For details, please refer to Figures 1-3 The self-locking cryogenic thermocouple clip 21 is an elastic locking component in the ultra-low temperature self-locking thermal coupling base 2 that achieves automatic clamping at low temperatures and completes low-resistance thermal coupling. It is fitted entirely onto the outside of the ultra-low temperature thermally conductive base 23, with a buffer insulation bushing 22 at the upper end for limiting its position. Internally, it surrounds the cryogenic receiving module's cooling shell 12, achieving self-locking without fasteners in the 77K and below temperature range due to the difference in thermal contraction of the materials. The entire clip is made of Al6061 aluminum alloy, whose coefficient of linear expansion at low temperatures is significantly higher than that of oxygen-free copper. When the device cools to an ultra-low temperature environment, the shrinkage dimension of the self-locking cryogenic thermocouple clip 21 is greater than that of the inner oxygen-free copper cryogenic receiving module's cooling shell 12 and the ultra-low temperature thermally conductive base 23, thereby generating a uniform circumferential interference clamping force, automatically clamping the cooling shell 12, eliminating assembly gaps, and significantly reducing interfacial contact thermal resistance. Al6061 has no risk of brittle fracture at ultra-low temperatures and is not prone to cracking under repeated elastic deformation, making it suitable for long-term thermal cycling conditions.

[0037] The self-locking cryogenic thermocouple clip 21 has a complete tubular structure, with multiple slots 9 circumferentially opened on the tube wall. The slots 9 are at 45° (in this embodiment, eight elastic sheets are selected, therefore this is...). The elastic sheets are evenly arranged in a ring. In this embodiment, eight elastic sheets are selected as the optimal option after repeated experiments under set conditions. The specific number of elastic sheets should be determined after experiments based on actual conditions. The elastic sheets are evenly arranged in a ring to form an integrated multi-sheet (specifically eight sheets in this embodiment) elastic ring structure. The slot gap width is 1mm (the specific width can be adjusted appropriately according to actual needs), and the tube wall thickness is 3mm (the specific thickness can be adjusted appropriately according to actual needs) to ensure that the elastic sheets have sufficient radial deformation margin. The low-temperature receiving module 1 can be smoothly inserted and removed at room temperature, while maintaining the overall rigidity of the tube body and avoiding plastic deformation during disassembly and assembly.

[0038] The slot 9 divides the tube wall into independent elastic sheets, with consistent elastic deformation capacity at all circumference positions. The clamping force generated during low-temperature contraction is evenly distributed on the outer wall of the low-temperature receiving module's heat-conducting shell 12, preventing localized stress concentration and ensuring a tight fit across the entire heat-conducting contact surface. The inner wall of the self-locking low-temperature thermocouple clip 21 and the outer wall of the ultra-low-temperature heat-conducting base 23 are assembled with a room-temperature tight fit. At low temperatures, the two are further bonded by the shrinkage difference between aluminum and copper, forming a double-layer low-resistance heat-conducting channel. A buffer insulation bushing 22 is fitted on its upper outer wall. The bushing is locked and limited by screws through the mounting and fixing through hole 8 and the mounting and fixing threaded hole 7, constraining the maximum opening of each elastic sheet and preventing excessive deformation of the elastic sheets during module insertion and removal, which could cause fatigue damage. The self-locking low-temperature thermocouple clip 21 and the ultra-low-temperature heat-conducting base 23 are fixed together to the ultra-low-temperature cold source mounting surface by screws (or other fixing methods), achieving a rigid connection between the structure and the cold source, ensuring rapid heat conduction to the cold source.

[0039] For details, please refer to Figure 3 The buffer insulation bushing 22 is a matching protective buffer component for the ultra-low temperature self-locking thermal coupling base 2. It is fitted onto the outer side of the upper end of the self-locking low temperature thermocouple clip 21 and is assembled with the self-locking low temperature thermocouple clip 21. It is an auxiliary structural component that balances the elastic clamping force, limits elastic deformation, and buffers low temperature stress concentration. The buffer insulation bushing 22 is made of nylon or epoxy glass (or other materials with a low temperature linear expansion coefficient similar to nylon or epoxy glass). Both types of materials have extremely low low temperature linear expansion coefficients, and their dimensional shrinkage is minimal in ultra-low temperature environments of 77K and below, so they will not deform significantly due to cooling. The materials themselves have excellent machinability and are easy to mill and drill. At the same time, the materials have a certain elastic buffering capacity, do not become brittle or crack easily at low temperatures, and have poor thermal conductivity, which can slightly block external room temperature heat leakage and reduce the heat load of the cold source.

[0040] See 3~ Figure 6 The buffer insulation bushing 22 has two types of mounting holes: a mounting threaded hole 7 and a mounting through hole 8. During assembly, the screw passes through the mounting through hole 8 and locks into the threaded hole at the upper end of the self-locking cryogenic thermocouple clamp 21, thus securing the buffer insulation bushing 22 firmly to the top of the self-locking cryogenic thermocouple clamp 21. The buffer insulation bushing 22 completely wraps around the upper periphery of the elastic sheet with slots 9 of the self-locking cryogenic thermocouple clamp 21, radially conforming to the outer circle of each elastic sheet, forming an outer ring limiting constraint structure; it does not interfere with the elastic contraction and clamping action of the middle and lower sections of the self-locking cryogenic thermocouple clamp 21, only limiting the maximum opening amplitude of the upper end of the elastic sheet.

[0041] During module insertion and removal, the elastic sheet formed by the slot 9 of the self-locking cryogenic thermocouple clip 21 expands outward. The outer ring of the buffer insulation bushing 22 acts as a limiting ring, constraining the maximum elastic tension of the elastic sheet and preventing irreversible plastic deformation caused by excessive expansion of the elastic sheet. This prevents the comb-shaped tooth root from breaking and significantly improves the service life of the self-locking cryogenic thermocouple clip 21. The buffer insulation bushing 22 fits tightly against the outer wall of the elastic sheet, providing uniform radial prestress to the entire self-locking cryogenic thermocouple clip 21. This allows the interference clamping force generated by low-temperature contraction to be evenly distributed along the circumference, avoiding excessive local clamping force that causes stress concentration. This ensures that the contact surface of the cryogenic receiving module's cooling shell 12 is evenly stressed and the thermal conductivity gap is consistent. The device cycles between room temperature and extremely low temperatures of 77K and below for extended periods. The difference in shrinkage between the aluminum thermocouple clips and the copper shell and base generates alternating stress. Nylon or epoxy glass materials have a buffering and damping effect, which can absorb stress peaks, alleviate fatigue wear caused by long-term thermal cycling of the elastic structure, and improve the reliability of the entire device in extremely low temperature cycling.

[0042] For details, please refer to Figures 1-3 The ultra-low temperature thermal conductive base 23 is the thermal conductive base of the ultra-low temperature self-locking thermal coupling base 2. It is directly fixed on the ultra-low temperature cold source mounting surface in the temperature range of 77K and below, and undertakes multiple functions such as cold source heat transfer, module positioning and guidance, and RF power supply blind insertion integration. It is combined with the self-locking low temperature thermocouple clip 21 and the buffer insulation bushing 22 to form a complete self-locking thermal conductive base.

[0043] The ultra-low temperature heat-conducting base 23 is integrally formed from oxygen-free copper. Oxygen-free copper has a high thermal conductivity and excellent heat transfer capability, which can quickly transfer the heat conducted from the low temperature receiving module 1 to the cold source. At the same time, the linear expansion coefficient of oxygen-free copper is lower than that of Al6061 aluminum alloy. After cooling, a shrinkage difference is generated between it and the outer self-locking low temperature thermocouple clip 21, which further tightens the mating surface, eliminates gaps, and reduces contact thermal resistance.

[0044] The outer cylindrical surface of the ultra-low temperature thermally conductive base 23 and the inner wall of the self-locking low-temperature thermocouple clip 21 are fitted together at room temperature. After assembly, they are locked together with screws (or other fixing methods) to the mounting surface of the ultra-low temperature cold source, achieving a rigid thermally conductive connection between the base and the cold source. The heat transfer path is short and there are no extra heat exchange gaps. A buffer insulation bushing 22 is installed on the upper outer side of the ultra-low temperature thermally conductive base 23. The bushing only restricts the upper end of the elastic plate of the thermocouple clip and will not interfere with the contact and thermal conduction between the base and the thermocouple clip and the module shell.

[0045] The top surface of the ultra-low temperature thermal conductive base 23 has a reserved installation position for assembling and installing the guide positioning pin 5 and the blind insertion assembly 4, integrating positioning and radio frequency interconnection functions. The ultra-low temperature thermal conductive base 23 has reserved pin mounting holes. One end of the guide positioning pin 5 is tightly fitted to the base to ensure that the pin will not loosen during long-term use; the other end of the pin extends outward and can be clearance-fitted with the positioning pin hole 6 of the cryogenic receiving module's cooling housing 12 to achieve blind insertion guidance of the cryogenic receiving module 1, reducing the difficulty of assembly alignment.

[0046] The ultra-low temperature thermally conductive base 23 integrates a blind-fit assembly 4. This port corresponds one-to-one with the signal port 3 of the cryogenic receiving core functional component 13. After the module completes the blind-fit assembly, the two sets of ports automatically connect and conduct, completing the RF signal transmission and power supply line connection in one go, without the need for separate wiring operations.

[0047] For details, please refer to Figures 1-3 Signal port 3 and blind mating assembly 4 are a pair of SMP (Sub-Miniature Push-on) blind mating RF and power supply interfaces, which are integrated on the low temperature receiving module 1 and the ultra-low temperature self-locking thermal coupling base 2 respectively. The two work together to realize the synchronous conduction of RF signal and power supply line during blind mating assembly, and are the core components of module electrical interconnection.

[0048] Signal port 3 is fixed on the cryogenic receiving core functional component 13 inside the cryogenic receiving module 1, including a signal input port 31 and a signal output port 32. The signal input port 31 is located on the upper part of the cryogenic receiving core functional component 13 and is used for signal input, while the signal output port 32 is located on the bottom of the cryogenic receiving core functional component 13 and is used for signal output. Signal port 3 is arranged on the corresponding mounting plane of the positioning pin hole 6 on the cryogenic receiving module's cooling housing 12 and moves with the overall insertion and removal of the cryogenic receiving module 1. Blind mating assembly 4 is integrated and installed on the ultra-low temperature thermal conductive base 23, including blind mating port 41 and blind mating combination matching port 42, with blind mating combination matching port 42 located at the upper end of blind mating port 41. The position of blind mating combination matching port 42 is precisely aligned with signal output port 32, and it is the fixed end interface of the ultra-low temperature self-locking thermal coupling base 2, always maintaining a stable connection with the cold source side line.

[0049] Signal port 3 and blind-fit assembly 4 are a complete set of compatible male and female blind-fit structures, eliminating the need for manual tightening or wiring. Relying on the guiding and limiting effect of the installation guide positioning pin 5 and positioning pin hole 6, when the low-temperature receiving module 1 is blindly inserted into the correct position, the signal output port 32 can be accurately inserted into the matching port 42 of the blind-fit assembly, automatically completing the locking and conduction; when the module is pulled out, the interface separates synchronously, and there is no additional wiring process for disassembly and assembly.

[0050] After signal port 3 is connected to blind-mating assembly 4, it is responsible for transmitting the weak radio frequency signal filtered and amplified by the cryogenic receiving core functional component 13. This is suitable for the high-frequency microwave transmission requirements of cryogenic receivers for radio telescopes and deep space exploration. The interface contact is stable, and there will be no signal attenuation or poor contact under cryogenic conditions. When the two work together, they synchronously supply working bias power to the cryogenic receiving core functional component 13, realizing integrated RF-DC common-feed transmission and simplifying the internal wiring structure. During assembly, mechanical positioning and pre-alignment are achieved by installing guide positioning pins 5 to ensure that signal port 3 and blind-mating assembly 4 are not forcibly squeezed or bumped. After cooling to an extremely low temperature of 77K and below, the entire structure automatically locks and limits the position, ensuring that the interface is tightly fitted and conductive for a long time, taking into account the requirements of mechanical locking, efficient heat conduction, and stable electrical interconnection.

[0051] For details, please refer to Figures 1-3 The installation guide positioning pin 5 and positioning pin hole 6 are matching positioning structures to achieve precise blind insertion and alignment between the low temperature receiving module 1 and the ultra-low temperature self-locking thermal coupling base 2. The two work together to complete the module insertion and removal guidance and low temperature dual limit, ensuring that the signal port 3 and the blind insertion component 4 are precisely connected, and simultaneously assisting in improving the overall locking effect under ultra-low temperature conditions.

[0052] Specifically, the installation guide positioning pin 5 is assembled on the ultra-low temperature heat-conducting base 23. The root of the pin is fixed to the heat-conducting base 23 with a tight fit to ensure that the pin does not loosen or shift during long-term thermal cycles. The pin rod extends upwards as an assembly guide reference. The pin is made of stainless steel (or other materials), which has low low-temperature shrinkage and strong dimensional stability. The positioning pin hole 6 is opened on the side wall of the cold-conducting shell 12 of the low-temperature receiving module. The hole diameter is slightly larger than the outer diameter of the pin rod, and the two form a clearance fit. During blind insertion assembly, the pin rod is inserted into the pin hole 6 first to complete the radial limit in advance and realize the pre-positioning of the module.

[0053] During room temperature module insertion and removal, the gap between the pin and the pin hole provides guidance and correction, offsetting minor alignment deviations during manual module placement and preventing hard impacts or squeezing damage to the signal port 3 and the blind insertion assembly 4. No manual fine-tuning is required during use, enabling rapid blind insertion and significantly improving the efficiency of large-scale array module assembly and disassembly. The low-temperature shrinkage of the stainless steel installation guide pin 5 is far less than that of the oxygen-free copper low-temperature receiving module's cooling housing 12. After cooling to extremely low temperatures of 77K and below, the shrinkage of the pin hole 6 is even greater, significantly reducing the assembly gap between the pin hole and the pin, forming an interference fit limit. This effect, combined with the circumferential clamping force of the self-locking low-temperature thermocouple clip 21, creates a dual constraint, simultaneously restricting the translation and rotation of the low-temperature receiving module 1 from both the outer cylindrical surface and the pin, ensuring long-term coaxial stability of the RF interface and preventing signal standing wave degradation.

[0054] For details, please refer to Figures 3-6The mounting and fixing threaded hole 7 and the mounting and fixing through hole 8 are two sets of assembly hole structures that are matched with the buffer insulation bushing 22. The two are used together with screws to lock and fix the buffer insulation bushing 22 to the self-locking low temperature thermocouple clamp 21, realize the bushing limit assembly, and coordinate to constrain the maximum opening amplitude of the elastic sheet.

[0055] The mounting and fixing through hole 8 is formed through the body of the buffer insulation bushing 22. The diameter of the hole is larger than the outer diameter of the fastening screw, allowing the screw to pass through the through hole 8 without obstruction. The mounting and fixing threaded hole 7 is formed on the upper end face of the self-locking cryogenic thermocouple clip 21. The thread specification matches the fastening screw, and it is aligned vertically with the mounting and fixing through hole 8 on the bushing to form a complete locking mounting position. During assembly, the buffer insulation bushing 22 is placed on the outer side of the upper end of the self-locking cryogenic thermocouple clip 21, so that the mounting and fixing through hole 8 is aligned with the mounting and fixing threaded hole 7 below. The fastening screw passes through the mounting and fixing through hole 8 from the outside of the bushing and screws into the mounting and fixing threaded hole 7 to tighten, thus firmly locking the buffer insulation bushing 22 to the top of the self-locking cryogenic thermocouple clip 21. The assembly and disassembly operations are simple and quick. The through hole 8 provides an assembly gap, allowing for minor adjustments to the bushing position during assembly, which facilitates alignment of the locking threads.

[0056] Example 2: Based on Embodiment 1, this embodiment provides an assembly method for an ultra-low temperature self-locking thermal coupling connection device, including four processes: module pre-assembly, base pre-assembly, blind mating, and low temperature self-locking molding. The specific steps are as follows: S1. Assemble the cryogenic receiving module: Securely install the cryogenic receiving core functional component 13 onto the internal mounting plane of the cryogenic receiving module's cooling housing 12. The cryogenic receiving core functional component 13 has its own signal port 3. After the device is fixed, lock the mounting plate 11 on the cryogenic receiving module onto the upper end face of the cryogenic receiving module's cooling housing 12 to obtain a complete and independently pluggable cryogenic receiving module 1. The side wall of the cryogenic receiving module's cooling housing 12 is pre-drilled with positioning pin holes 6.

[0057] S2. Assemble the ultra-low temperature self-locking thermal coupling base 2: The buffer insulation bushing 22 has a mounting and fixing through hole 8 and a mounting and fixing threaded hole 7. The screw passes through the mounting and fixing through hole 8 and is screwed into the mounting and fixing threaded hole 7 to lock and fix the buffer insulation bushing 22 to the upper end of the self-locking low temperature thermocouple clip 21. The wall of the self-locking low temperature thermocouple clip 21 is machined with a groove 9, and the whole assembly is tightly fitted to the outside of the ultra-low temperature thermal conductive base 23. The ultra-low temperature thermal conductive base 23 is pre-installed with the installation guide positioning pin 5 and the blind insertion assembly 4. After the assembly is completed, the ultra-low temperature thermal conductive base 23, together with the outer self-locking low temperature thermocouple clip 21 and the buffer insulation bushing 22, is locked as a whole on the ultra-low temperature cold source mounting surface in the temperature range of 77K and below, and the base pre-assembly is completed.

[0058] S3. Blind insertion assembly: The operator holds the mounting plate 11 on the cryogenic receiving module and moves it down so that the installation guide positioning pin 5 is aligned with the insertion positioning pin hole 6. The guide is corrected by the gap between the pin and the pin hole. The cryogenic receiving module 1 is continuously pressed down until it is in place. At this time, the signal output port 32 of the cryogenic receiving core functional component 13 is precisely inserted and connected with the blind insertion combination matching port 42 on the ultra-low temperature heat conduction base 23, completing the mechanical positioning and electrical interconnection in one go.

[0059] S4. Low-temperature self-locking molding: The entire device is sent into a low-temperature chamber to cool to an extremely low temperature environment of 77K and below. Since the self-locking low-temperature thermocouple clamp 21 is made of Al6061 aluminum alloy, its low-temperature shrinkage is greater than that of the oxygen-free copper material of the low-temperature receiving module cooling shell 12, thereby generating a uniform circumferential interference clamping force, automatically clamping the outer wall of the low-temperature receiving module cooling shell 12, eliminating the interface air gap, and simultaneously realizing fastener-free mechanical locking and low-resistance high-efficiency heat conduction, and the device enters a stable working state.

[0060] In summary, the present invention has the following advantages: This invention consists of two main modules: a low-temperature receiving module 1 and an ultra-low-temperature self-locking thermal coupling base 2. Room-temperature blind insertion is achieved by using installation guide pins 5 and positioning pin holes 6 for guidance. During insertion and removal, the signal port 3 and the blind insertion component 4 synchronously conduct electrical circuits, simplifying array disassembly and maintenance. The self-locking low-temperature thermocouple clip 21 is made of Al6061 aluminum alloy with slots 9, forming a shrinkage difference with the oxygen-free copper low-temperature receiving module's cooling shell 12 and the ultra-low-temperature thermal base 23. It automatically locks itself at low temperatures, eliminating the need for additional fasteners and preventing loosening during thermal cycles. All thermally conductive components are made of oxygen-free copper, ensuring a tight fit and low contact thermal resistance, allowing for rapid heat dissipation from the core low-temperature receiving component 13 and stabilizing the low-temperature operating environment. The buffer insulation bushing 22 is locked to the upper end of the thermocouple clip 21 via mounting and fixing through holes 8 and mounting and fixing threaded holes 7, limiting excessive deformation of the elastic sheet, buffering alternating stress, and reducing heat loss. The entire structure is standardized and the components are interchangeable. It has the advantages of convenient assembly, reliable locking, efficient heat conduction and long service life, and is suitable for use in large-scale cryogenic receiving arrays.

[0061] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Terms such as "upper," "lower," "left," "right," "front," and "rear" used in the invention 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.

[0062] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A low-temperature self-locking thermal coupling connection device, characterized in that, Includes a low-temperature receiving module and an ultra-low temperature self-locking thermal coupling base; The low-temperature receiving module includes a mounting plate on the low-temperature receiving module, a cooling shell for the low-temperature receiving module, and a core functional component for low-temperature receiving. The core functional component for low-temperature receiving is encapsulated and fixed inside the cooling shell for the low-temperature receiving module, and the mounting plate on the low-temperature receiving module is fixed to the upper end of the cooling shell for the low-temperature receiving module. The ultra-low temperature self-locking thermal coupling base includes a self-locking low temperature thermocouple clip, a buffer insulation bushing, and an ultra-low temperature thermally conductive base. The ultra-low temperature thermally conductive base and the self-locking low temperature thermocouple clip are fixed together to the ultra-low temperature cold source mounting surface. The self-locking low temperature thermocouple clip is a tubular structure, including multiple elastic plates. The elastic plates are evenly distributed in a ring to form an elastic encircling structure. Slots are provided between adjacent elastic plates, and the slots have a consistent width. The buffer insulation bushing is arranged outside the upper open ring portion of the elastic plates of the self-locking low temperature thermocouple clip.

2. The ultra-low temperature self-locking thermal coupling connection device according to claim 1, characterized in that, The self-locking cryogenic thermocouple clamp is made of aluminum alloy.

3. The ultra-low temperature self-locking thermal coupling connection device according to claim 1, characterized in that, The cryogenic receiving module's cooling shell, ultra-low temperature heat-conducting base, and the shell of the cryogenic receiving core functional components are all made of oxygen-free copper.

4. The ultra-low temperature self-locking thermal coupling connection device according to claim 1, characterized in that, The buffer insulation bushing is made of nylon or epoxy glass. The buffer insulation bushing has a mounting and fixing through hole and a mounting and fixing threaded hole, and is locked and fixed to the upper end of the open ring part of the self-locking low temperature thermocouple clip elastic sheet by screws.

5. The ultra-low temperature self-locking thermal coupling connection device according to claim 1, characterized in that, The ultra-low temperature heat-conducting base is provided with mounting guide positioning pins, and the cooling shell of the low temperature receiving module has positioning pin holes that match the mounting guide positioning pins. The low temperature receiving module achieves blind insertion and docking with the ultra-low temperature self-locking thermal coupling base by installing the mounting guide positioning pins.

6. The ultra-low temperature self-locking thermal coupling connection device according to claim 1, characterized in that, The bottom of the cryogenic receiving core functional component is provided with a signal output port, and the ultra-low temperature heat-conducting base is provided with a blind-mating assembly port; the signal output port and the blind-mating assembly port are plugged in and matched, and the signal and power supply interconnection is completed synchronously after docking.

7. The ultra-low temperature self-locking thermal coupling connection device according to claim 5, characterized in that, One end of the installation guide positioning pin is tightly fitted and fixed to the ultra-low temperature heat-conducting base, while the other end is loosely fitted to the positioning pin hole of the low temperature receiving module's cooling shell.

8. The cryogenic self-locking thermal coupling connection device according to claim 5, characterized in that, The low-temperature shrinkage rate of the installation guide positioning pin is less than the shrinkage of the positioning pin hole.

9. The cryogenic self-locking thermal coupling connection device according to claim 1, characterized in that, The mounting surface of the top plate on the low-temperature receiving module and the cooling shell of the low-temperature receiving module serve as the force-bearing panel for manual insertion and removal of the low-temperature receiving module.

10. An assembly method for an ultra-low temperature self-locking thermal coupling connection device according to any one of claims 1 to 9, characterized in that, Includes the following steps: S1. Assemble the cryogenic receiving module: Fix the core functional components of the cryogenic receiving module to the inner wall of the cryogenic receiving module's cooling shell, and then assemble the top plate on the cryogenic receiving module. S2. Assemble the ultra-low temperature self-locking thermal coupling base: Fix the buffer insulation bushing to the upper end of the self-locking low temperature thermocouple clip, and fit the self-locking low temperature thermocouple clip on the outside of the ultra-low temperature thermal conductive base. Fix the whole assembly to the ultra-low temperature cold source. S3, Blind mating: The top plate is installed on the handheld low temperature receiver module, and the base is inserted by relying on the installation guide positioning pin to realize the blind mating of the signal output port and the matching port of the blind mating combination; S4. Low-temperature self-locking: When the device is cooled to an extremely low temperature environment of 77K and below, the shrinkage of the self-locking low-temperature thermocouple clamp is greater than that of the inner copper component, generating an interference clamping force to automatically tighten the low-temperature receiving module's cooling shell, simultaneously achieving mechanical locking and efficient heat conduction.

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