Rapid cooling device for helium throttling refrigerating machine and cooling method of rapid cooling device

Abstract

The invention discloses a rapid cooling device of a helium throttling refrigerator and a cooling method of the rapid cooling device, and relates to the technical field of helium throttling refrigerators, the rapid cooling device comprises a helium throttling refrigerator body and a pre-cooling pipeline, and the helium throttling refrigerator body comprises a pre-cooling machine body, a compressor unit, a heat exchange circulation pipeline and a vacuum tank; the heat exchange circulation pipeline comprises a high-pressure side pipeline and a low-pressure side pipeline, the high-pressure side pipeline and the low-pressure side pipeline are jointly connected with heat exchanger bodies, gas in the high-pressure side pipeline is cooled after passing through the heat exchanger bodies, gas in the low-pressure side pipeline is heated after passing through the heat exchanger bodies, and a pre-cooling heat exchanger body is further arranged on the high-pressure side pipeline. Gas in the high-pressure side pipeline is cooled after passing through the precooling heat exchanger body, the gas inlet end of the precooling pipeline is connected with the gas outlet end of the high-pressure side pipeline, the gas outlet end of the precooling pipeline is connected with the gas inlet end of the low-pressure side pipeline or the gas inlet end of the high-pressure side pipeline, and the precooling pipeline penetrates through the heat exchanger body. According to the invention, rapid refrigeration and cooling of the helium throttling refrigerator main body can be realized.

Description

Technical Field

[0001] The present invention relates to the technical field of helium throttle refrigerators, and particularly to a rapid cooling device for a helium throttle refrigerator and a cooling method thereof. Background Art

[0002] The development of aerospace technology has provided important assistance for humans to explore the universe. In space exploration missions, detectors have an urgent need for cryogenic technology to obtain higher sensitivity, signal-to-noise ratio, resolution and reduce noise. The pre-cooled helium throttle refrigerator driven by a linear compressor has the advantages of long life, low weight, high reliability, and no moving parts at the cold end, and has important academic research and application value.

[0003] However, the existing helium throttle refrigerator only uses a pre-cooler to cool and lower the temperature of helium. It should be noted that the efficiency of the pre-cooler transferring cold energy to the end of the helium throttle refrigerator determines the overall cooling time of the refrigerator. If only relying on the pre-cooler for cooling, the cooling time usually takes more than dozens of hours, which greatly affects the working efficiency and effective working time of the scientific payload.

[0004] Therefore, there is an urgent need in the art for a rapid cooling device for a helium throttle refrigerator and a cooling method thereof to solve the above problems. Summary of the Invention

[0005] The object of the present invention is to provide a rapid cooling device for a helium throttle refrigerator and a cooling method thereof to solve the problems existing in the above prior art, and to be able to achieve rapid refrigeration and cooling of the main body of the helium throttle refrigerator.

[0006] To achieve the above object, the present invention provides the following solution:

[0007] The present invention discloses a rapid cooling device for a helium throttling refrigerator, which includes a helium throttling refrigerator main body and a precooling pipeline. The helium throttling refrigerator main body includes a precooling machine body, a compressor unit, a heat exchange circulation pipeline, and a vacuum tank. The heat exchange circulation pipeline includes a high-pressure side pipeline and a low-pressure side pipeline. The intake end of the high-pressure side pipeline is connected to the outlet end of the compressor unit, the outlet end of the high-pressure side pipeline is connected to the intake end of the low-pressure side pipeline, and the outlet end of the low-pressure side pipeline is connected to the intake end of the compressor unit. The high-pressure side pipeline and the low-pressure side pipeline are jointly connected with a plurality of heat exchanger bodies. The gas in the high-pressure side pipeline is cooled after passing through each heat exchanger body, and the gas in the low-pressure side pipeline is heated after passing through each heat exchanger body. A plurality of precooling heat exchanger bodies are also provided on the high-pressure side pipeline. The refrigerating end of the precooling machine body provides a cold source for the precooling heat exchanger bodies. The gas in the high-pressure side pipeline is cooled after passing through each precooling heat exchanger body. The intake end of the precooling pipeline is connected to the outlet end of the high-pressure side pipeline, and the outlet end of the precooling pipeline is connected to the intake end of the low-pressure side pipeline or the high-pressure side pipeline. The precooling pipeline passes through the heat exchanger bodies, and each heat exchanger body, each precooling heat exchanger body, and the refrigerating end of the precooling machine body are all located in the vacuum tank.

[0008] Preferably, the compressor unit includes a first-stage compressor and a second-stage compressor that are connected in sequence at the head and tail.

[0009] Preferably, each of the heat exchanger bodies is a first-stage heat exchanger, a second-stage heat exchanger, and a third-stage heat exchanger, and each of the precooling heat exchanger bodies is a first-stage precooling heat exchanger, a second-stage precooling heat exchanger, and a third-stage precooling heat exchanger. The first-stage precooling heat exchanger is arranged between the first-stage heat exchanger and the second-stage heat exchanger, the second-stage precooling heat exchanger is arranged between the second-stage heat exchanger and the third-stage heat exchanger, and the third-stage precooling heat exchanger is arranged at one end of the third-stage heat exchanger away from the second-stage heat exchanger.

[0010] Preferably, a first cold shield body and a second cold shield body are provided in the vacuum tank. The second cold shield body is arranged inside the first cold shield body. The first-stage heat exchanger is located in the cavity between the vacuum tank and the first cold shield body. The second-stage heat exchanger and the first-stage precooling heat exchanger are located in the cavity between the first cold shield body and the second cold shield body. The third-stage heat exchanger, the second-stage precooling heat exchanger, and the third-stage precooling heat exchanger are all located inside the second cold shield body.

[0011] Preferably, the first cold shield body includes a first cold shield shell and a first cold shield bottom plate. The first cold shield shell is fixed on the first cold shield bottom plate, and the first cold shield bottom plate is connected to the refrigerating end of the precooling machine body;

[0012] The second cold screen body includes a second cold screen housing and a second cold screen bottom plate. The second cold screen housing is fixed on the second cold screen bottom plate, and the second cold screen bottom plate is connected to the refrigerating end of the pre-cooling machine body.

[0013] Preferably, the materials of the first cold screen bottom plate and the second cold screen bottom plate are both copper; aluminum foils are installed on the inner walls of the first cold screen housing and the second cold screen housing.

[0014] Preferably, the pre-cooling machine body is a two-stage pre-cooling machine. The pre-cooling machine body includes a pre-cooling machine first-stage cold head and a pre-cooling machine second-stage cold head. The pre-cooling machine first-stage cold head is connected to the first cold screen bottom plate, and the pre-cooling machine second-stage cold head is connected to the second cold screen bottom plate.

[0015] Preferably, an evaporator is connected to the air inlet end of the low-pressure side pipeline. A throttling structure is connected between the three-stage pre-cooling heat exchanger and the evaporator. The three-stage pre-cooling heat exchanger and the evaporator are connected by a heat bridge. The air inlet end of the pre-cooling pipeline is connected between the three-stage pre-cooling heat exchanger and the throttling structure.

[0016] Preferably, a stop valve is provided on the pre-cooling pipeline.

[0017] The present invention discloses a cooling method for a rapid cooling device of a helium throttling refrigerator. Based on the above-mentioned rapid cooling device of a helium throttling refrigerator, it includes the following steps:

[0018] S1. Start the pre-cooling machine body and the compressor unit, and open the heat exchange circulation pipeline and the pre-cooling pipeline;

[0019] S2. The gas in the high-pressure side pipeline is sequentially cooled after passing through each heat exchanger body and the pre-cooling heat exchanger body. The cooled gas will return to the heat exchange circulation pipeline through the pre-cooling pipeline again;

[0020] S3. When the gas in the heat exchange circulation pipeline is reduced to the working temperature, increase the working power of the compressor unit and close the pre-cooling pipeline, so that the gas circulates in the high-pressure side pipeline and the low-pressure side pipeline.

[0021] The present invention has achieved the following technical effects compared with the prior art:

[0022] The present invention is provided with a precooling pipeline. The low-temperature gas flowing out of the high-pressure side pipeline will first pass through the precooling pipeline, so that it does not flow through the low-pressure side pipeline. The gas with a lower temperature in the precooling pipeline cools the gas in the high-pressure side pipeline. Under the action of each precooling heat exchanger body and the precooling pipeline, the gas in the heat exchange circulation pipeline is quickly cooled. When the temperature in the heat exchange circulation pipeline drops to a certain value, the precooling pipeline is closed and the low-pressure side pipeline is opened, so that the gas can perform a normal working cycle in the heat exchange circulation pipeline.

[0023] The present invention can realize the rapid cooling effect of the helium throttle refrigerator main body, thus effectively shortening the time of the cooling process and improving the experimental efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0025] Figure 1 It is a schematic structural diagram of the rapid cooling device of the helium throttle refrigerator in Embodiment 1;

[0026] In the figure: 1 - precooler body; 101 - first-stage cold head of the precooler; 102 - second-stage cold head of the precooler; 2 - compressor unit; 201 - first-stage compressor; 202 - second-stage compressor; 3 - heat exchange circulation pipeline; 301 - high-pressure side pipeline; 302 - low-pressure side pipeline; 303 - first-stage heat exchanger; 304 - first-stage precooling heat exchanger; 305 - second-stage heat exchanger; 306 - second-stage precooling heat exchanger; 307 - third-stage heat exchanger; 308 - third-stage precooling heat exchanger; 309 - throttling structure; 310 - evaporator; 4 - precooling pipeline; 401 - stop valve; 402 - first-stage cold recovery pipeline; 403 - second-stage cold recovery pipeline; 5 - heat bridge; 6 - first cold shield body; 7 - second cold shield body; 8 - vacuum tank. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the protection scope of the present invention.

[0028] The object of the present invention is to provide a rapid cooling device for a helium throttle refrigerator and a cooling method thereof, so as to solve the problems existing in the above-mentioned prior art and be able to achieve rapid refrigeration and cooling of the helium throttle refrigerator main body.

[0029] In order to make the above objects, features and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] Embodiment 1

[0031] As Figure 1 shown, this embodiment provides a rapid cooling device for a helium throttle refrigerator, including a helium throttle refrigerator main body and a precooling pipeline 4. The helium throttle refrigerator main body includes a precooling machine body 1, a compressor unit 2, a heat exchange circulation pipeline 3 and a vacuum tank 8. The heat exchange circulation pipeline 3 includes two pipelines, namely a high-pressure side pipeline 301 and a low-pressure side pipeline 302. The intake end of the high-pressure side pipeline 301 is connected to the outlet end of the compressor unit 2, the outlet end of the high-pressure side pipeline 301 is connected to the intake end of the low-pressure side pipeline 302, and the outlet end of the low-pressure side pipeline 302 is connected to the intake end of the compressor unit 2, thereby forming a complete circulation pipeline. A number of heat exchanger bodies are commonly connected to the high-pressure side pipeline 301 and the low-pressure side pipeline 302, and each heat exchanger body can be an existing shell-and-tube heat exchanger or a tube-shell heat exchanger, that is, the heat exchanger body has two paths, namely a tube side and a shell side, and the high-pressure side pipeline 301 and the low-pressure side pipeline 302 are respectively connected to the tube side and the shell side (or the shell side and the tube side), so as to realize heat exchange between the gases respectively transported by the high-pressure side pipeline 301 and the low-pressure side pipeline 302 in the heat exchanger body, that is, the gas in the high-pressure side pipeline 301 is cooled after passing through each heat exchanger body, and the gas in the low-pressure side pipeline 302 is heated after passing through each heat exchanger body. A number of precooling heat exchanger bodies are also provided on the high-pressure side pipeline 301, and the refrigerating end of the precooling machine body 1 provides a cold source for the precooling heat exchanger bodies, so that the gas in the high-pressure side pipeline 301 can be cooled after passing through each precooling heat exchanger body. The intake end of the precooling pipeline 4 is connected near the outlet end of the high-pressure side pipeline 301, the outlet end of the precooling pipeline 4 is connected near the outlet end of the low-pressure side pipeline 302 or near the intake end of the high-pressure side pipeline 301, and the precooling pipeline 4 passes through the heat exchanger body. It should be noted that the precooling pipeline 4 can pass through all the heat exchanger bodies or part of the heat exchanger bodies, which can be adjusted according to actual needs. Each heat exchanger body, each precooling heat exchanger body and the refrigerating end of the precooling machine body 1 are all located in the vacuum tank 8.

[0032] During actual use, first start the pre-cooling machine body 1, turn off the compressor unit 2, open the heat exchange circulation pipeline 3 and the pre-cooling pipeline 4. Then, the gas in the high-pressure side pipeline 301 (the gas in this embodiment is helium) is cooled down after passing through each heat exchanger body and the pre-cooling heat exchanger body in sequence. The cooled gas will return to the high-pressure side pipeline 301 or the low-pressure side pipeline 302 in the heat exchange circulation pipeline 3 again through the pre-cooling pipeline 4 (specifically, which one to return to depends on where the pre-cooling pipeline 4 is connected. The reason why the pre-cooling pipeline 4 can be connected to either the high-pressure side pipeline 301 or the low-pressure side pipeline 302 is that during this pre-cooling process, the compressor unit 2 does not operate, so connecting to the high-pressure side pipeline 301 or the low-pressure side pipeline 302 is essentially the same). When the gas in the heat exchange circulation pipeline 3 drops to the working temperature, start the compressor unit 2 and close the pre-cooling pipeline 4, so that the gas circulates between the high-pressure side pipeline 301 and the low-pressure side pipeline 302, enabling the helium throttle refrigerator body to work normally. In this embodiment, because there is a pre-cooling pipeline 4, the gas in the high-pressure side pipeline 301 is quickly cooled down under the dual action of the pre-cooling machine body 1 and the pre-cooling pipeline 4.

[0033] In this embodiment, the compressor unit 2 includes a first-stage compressor 201 and a second-stage compressor 202 connected end to end in sequence. The low-pressure gas from the low-pressure side pipeline 302 will first be compressed by the second-stage compressor 202, and then enter the first-stage compressor 201 for air compression. The gas flowing out of the first-stage compressor 201 becomes high-pressure gas and enters the high-pressure side pipeline 301. The reason for setting two compressors is to better adjust the gas pressure output to the high-pressure side pipeline 301 so that it can reach the required pressure value.

[0034] In this embodiment, there are a total of three heat exchanger bodies. Along the flow direction of the gas in the high-pressure side pipeline 301, each heat exchanger body is a first-stage heat exchanger 303, a second-stage heat exchanger 305, and a third-stage heat exchanger 307 respectively. Correspondingly, there are also three pre-cooling heat exchanger bodies. Along the flow direction of the gas in the high-pressure side pipeline 301, each pre-cooling heat exchanger body is a first-stage pre-cooling heat exchanger 304, a second-stage pre-cooling heat exchanger 306, and a third-stage pre-cooling heat exchanger 308 respectively.

[0035] And the heat exchanger bodies and the pre-cooling heat exchanger bodies are distributed alternately. Specifically, the first-stage pre-cooling heat exchanger 304 is arranged between the first-stage heat exchanger 303 and the second-stage heat exchanger 305, the second-stage pre-cooling heat exchanger 306 is arranged between the second-stage heat exchanger 305 and the third-stage heat exchanger 307, and the third-stage pre-cooling heat exchanger 308 is arranged at one end of the third-stage heat exchanger 307 far from the second-stage heat exchanger 305.

[0036] That is, the gas in the high-pressure side pipeline 301 will sequentially pass through six components: the first-stage heat exchanger 303, the first-stage precooling heat exchanger 304, the second-stage heat exchanger 305, the second-stage precooling heat exchanger 306, the third-stage heat exchanger 307, and the third-stage precooling heat exchanger 308 for sequential cooling. And the gas in the low-pressure side pipeline 302 will sequentially pass through three components: the third-stage heat exchanger 307, the second-stage heat exchanger 305, and the first-stage heat exchanger 303 for sequential heating.

[0037] In addition, the part of the precooling pipeline 4 located inside the first-stage heat exchanger 303 is the first-stage cold recovery pipeline 402, and the part of the precooling pipeline 4 located inside the second-stage heat exchanger 305 is the second-stage cold recovery pipeline 403. It should be noted that the precooling pipeline 4 does not pass through the third-stage heat exchanger 307 because the temperature of the gas in the precooling pipeline 4 and the high-pressure side pipeline 301 in the third-stage heat exchanger 307 is almost the same, so the heat exchange effect is not obvious. Therefore, the precooling pipeline 4 does not pass through the third-stage heat exchanger 307.

[0038] In this embodiment, a first cold shield body 6 and a second cold shield body 7 are provided inside the vacuum tank 8, and the second cold shield body 7 is arranged inside the first cold shield body 6. The vacuum tank 8, the first cold shield body 6, and the second cold shield body 7 can divide the space inside the vacuum tank 8 into three cavities. These three cavities are relatively independent, and the heat insulation between two adjacent cavities is good.

[0039] The first-stage heat exchanger 303 is located in the cavity between the vacuum tank 8 and the first cold shield body 6, the second-stage heat exchanger 305 and the first-stage precooling heat exchanger 304 are located in the cavity between the first cold shield body 6 and the second cold shield body 7, and the third-stage heat exchanger 307, the second-stage precooling heat exchanger 306, and the third-stage precooling heat exchanger 308 are all located inside the second cold shield body 7. The temperatures of the heat exchanger structures in different cavities are different from each other and do not affect each other.

[0040] In this embodiment, the first cold shield body 6 includes a first cold shield housing and a first cold shield bottom plate. The first cold shield housing is in a cylindrical structure. The first cold shield housing is fixed to the first cold shield bottom plate by bolts. The first cold shield bottom plate is connected to the refrigerating end of the precooling machine body 1. The first cold shield bottom plate is made of a material with good thermal conductivity. The first cold shield bottom plate can transfer the cold quantity of the precooling machine body 1 to the inside of the first cold shield body 6 and can also increase the cold dissipation area.

[0041] The structure of the second cold shield body 7 is basically the same as that of the first cold shield body 6. The second cold shield body 7 includes a second cold shield housing and a second cold shield bottom plate. The second cold shield housing is in a cylindrical structure. The second cold shield housing is fixed to the second cold shield bottom plate by bolts. The second cold shield bottom plate is connected to the refrigerating end of the precooling machine body 1. The second cold shield bottom plate is made of a material with good thermal conductivity. The second cold shield bottom plate can transfer the cold quantity of the precooling machine body 1 to the inside of the second cold shield body 7 and can also increase the cold dissipation area.

[0042] In this embodiment, the materials of the first cold screen bottom plate and the second cold screen bottom plate are both copper. Copper has good thermal conductivity. Of course, those skilled in the art can also replace it with other metals with good thermal conductivity, not limited to this one kind.

[0043] The inner walls of the first cold screen housing and the second cold screen housing are installed with aluminum foil, so as to play a role in heat insulation.

[0044] In this embodiment, the pre-cooling machine body 1 is a two-stage pre-cooling machine. Specifically, an existing GM two-stage refrigerator or pulse tube refrigerator can be used, etc. The pre-cooling machine body 1 includes two refrigeration ends, namely the pre-cooling machine first-stage cold head 101 and the pre-cooling machine second-stage cold head 102. The temperature of the pre-cooling machine second-stage cold head 102 is lower than that of the pre-cooling machine first-stage cold head 101.

[0045] During actual installation, the pre-cooling machine first-stage cold head 101 is connected to the first cold screen bottom plate, so as to provide cooling capacity for the inside of the first cold screen body 6 through the first cold screen bottom plate. Similarly, the pre-cooling machine second-stage cold head 102 is connected to the second cold screen bottom plate, so as to provide cooling capacity for the inside of the second cold screen body 7.

[0046] It should be noted here that the first-stage pre-cooling heat exchanger 304 and the second-stage pre-cooling heat exchanger 306 have the same structure. In essence, it is a simple pre-cooling container. Place the pre-cooling container on the corresponding first cold screen bottom plate or second cold screen bottom plate. The low temperature on the first cold screen bottom plate or second cold screen bottom plate will cool the pre-cooling container through heat transfer, and the high-pressure side pipeline 301 will pass through the pre-cooling container, so as to cool the high-pressure side pipeline 301. Or, the high-pressure side pipeline 301 at the corresponding position can also be directly fixed on the first cold screen bottom plate or the second cold screen bottom plate, which can also play a role in cooling it.

[0047] In this embodiment, the intake end of the low-pressure side pipeline 302 is connected to an evaporator 310. A throttling structure 309 is connected between the third-stage pre-cooling heat exchanger 308 and the evaporator 310. The throttling structure 309 can be a throttle valve, a throttle orifice or a capillary tube. The third-stage pre-cooling heat exchanger 308 and the evaporator 310 are connected by a heat bridge 5. The heat bridge 5 is a connecting piece with good thermal conductivity, such as a connecting piece made of copper. Its purpose is to realize the heat transfer between the evaporator 310 and the third-stage pre-cooling heat exchanger 308. The intake end of the pre-cooling pipeline 4 is connected between the third-stage pre-cooling heat exchanger 308 and the throttling structure 309.

[0048] When in the pre-cooling stage of the helium throttling refrigerator main body, most of the gas from the high-pressure side pipeline 301 will pass through the pre-cooling pipeline 4 for rapid pre-cooling. Of course, a small amount of gas will flow into the low-pressure side pipeline 302 through the capillary structure and the evaporator 310. During this process, it is in a gas state.

[0049] When the helium throttle refrigerator main body is in normal operation, part of the gaseous helium in the evaporator 310 will be converted into liquid helium. This is because the cold quantity in the second cold shield body 7 diffuses, making the temperature in the evaporator 310 relatively low. The gas from the high-pressure side pipeline 301 will enter the three-stage precooling heat exchanger 308. Since the evaporator 310 and the three-stage precooling heat exchanger 308 are connected by the heat bridge 5, the evaporator 310 will provide cold quantity for the three-stage precooling heat exchanger 308, enabling the three-stage precooling heat exchanger 308 to cool the gas in the high-pressure side pipeline 301. When the gaseous helium flowing out of the three-stage precooling heat exchanger 308 passes through the throttling structure 309, part of it will be converted into liquid helium. At the same time, part of the liquid helium in the evaporator 310 will transfer heat to the three-stage precooling heat exchanger 308, so its own temperature will rise. The liquid helium becomes gaseous helium and flows into the low-pressure side pipeline 302, thus completing a cycle.

[0050] In addition, temperature sensors can be set at the evaporator 310 or the three-stage precooling heat exchanger 308 to monitor the temperature in the system in real time. When the expected temperature is reached during the precooling stage, the compressor unit 2 can be started and the precooling pipeline 4 can be closed to enter the working state.

[0051] In this embodiment, a stop valve 401 is provided on the precooling pipeline 4. The stop valve 401 here is a manual valve, which is used to control the flow of the precooling pipeline 4. It should be noted that it can be easily seen from the figure that the stop valve 401 is set near the outlet end of the low-pressure side pipeline 302. When it is closed, some gas in the high-pressure side pipeline 301 may flow into the precooling pipeline 4. However, at this time, the compressor unit 2 has already started working, and the pipe diameters of the first-stage cold recovery pipeline 402 and the second-stage cold recovery pipeline 403 are 1 mm smaller than those of the high-pressure side pipeline 301 and the low-pressure side pipeline 302. Therefore, the gas flow rate in the precooling pipeline 4 is much smaller than that in the high-pressure side pipeline 301 and the low-pressure side pipeline 302. And due to the stop valve 401 being in the closed state, the gas flow in the precooling pipeline 4 is poor, so it will not affect the gas temperature in the high-pressure side pipeline 301 and the low-pressure side pipeline 302.

[0052] In other embodiments, the stop valve 401 can be changed to an electric valve and set near the inlet end of the precooling pipeline 4. At this time, when the stop valve 401 is closed, no gas will enter the precooling pipeline 4.

[0053] Embodiment 2

[0054] This embodiment provides a cooling method for a rapid cooling device of a helium throttle refrigerator. Based on the rapid cooling device of a helium throttle refrigerator disclosed in Embodiment 1, it includes the following steps:

[0055] S1. Start the pre-cooling machine body 1 and the compressor unit 2. It should be noted that at this time, the compressor unit 2 is in a low-power operation state, that is, it only maintains the normal flow of the gas in the heat exchange circulation pipeline 3, and there is no need to compress the gas, or the compression effect is very small. Open the stop valve 401 of the heat exchange circulation pipeline 3 (the heat exchange circulation pipeline 3 can be provided with a valve or not. If a valve is provided, the corresponding valve needs to be opened. If not, the heat exchange circulation pipeline 3 is in an always-open state) and the pre-cooling pipeline 4.

[0056] S2. The gas in the high-pressure side pipeline 301 is cooled down after passing through each heat exchanger body and the pre-cooling heat exchanger body in turn. Most of the cooled gas will return to the heat exchange circulation pipeline 3 through the pre-cooling pipeline 4 again. Of course, a small part will also flow into the low-pressure side pipeline 302.

[0057] S3. When the gas in the heat exchange circulation pipeline 3 drops to the working temperature, generally about 25K, increase the working efficiency of the compressor unit and close the pre-cooling pipeline 4, so that the gas undergoes a formal compression throttling cycle process in the high-pressure side pipeline 301 and the low-pressure side pipeline 302. At this time, it is the working state of the helium throttling refrigerator main body.

[0058] In the present invention, specific examples are used to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A rapid cooling device for a helium throttle refrigerator, characterized in that: It includes a helium throttle refrigerator main body and a precooling pipeline (4). The helium throttle refrigerator main body includes a precooler main body (1), a compressor unit (2), a heat exchange circulation pipeline (3), and a vacuum tank (8). The heat exchange circulation pipeline (3) includes a high-pressure side pipeline (301) and a low-pressure side pipeline (302). The intake end of the high-pressure side pipeline (301) is connected to the outlet end of the compressor unit (2). The outlet end of the high-pressure side pipeline (301) is connected to the intake end of the low-pressure side pipeline (302). The outlet end of the low-pressure side pipeline (302) is connected to the intake end of the compressor unit (2). A number of heat exchanger main bodies are commonly connected to the high-pressure side pipeline (301) and the low-pressure side pipeline (302). The gas in the high-pressure side pipeline (301) is cooled after passing through each of the heat exchanger main bodies. The gas in the low-pressure side pipeline (302) is heated after passing through each of the heat exchanger main bodies. A number of precooling heat exchanger main bodies are also provided on the high-pressure side pipeline (301). The refrigerating end of the precooler main body (1) provides a cold source for the precooling heat exchanger main bodies. The gas in the high-pressure side pipeline (301) is cooled after passing through each of the precooling heat exchanger main bodies. The intake end of the precooling pipeline (4) is connected to the outlet end of the high-pressure side pipeline (301). The outlet end of the precooling pipeline (4) is connected to the intake end of the low-pressure side pipeline (302) or the high-pressure side pipeline (301). The precooling pipeline (4) passes through the heat exchanger main bodies. The refrigerating ends of each of the heat exchanger main bodies, each of the precooling heat exchanger main bodies, and the precooler main body (1) are all located inside the vacuum tank (8).

2. The rapid cooling device of a helium throttle refrigerator according to claim 1, characterized in that: The compressor unit (2) includes a first-stage compressor (201) and a second-stage compressor (202) that are sequentially connected end to end.

3. The rapid cooling device of a helium throttle refrigerator according to claim 1, characterized in that: Each of the heat exchanger main bodies is respectively a first-stage heat exchanger (303), a second-stage heat exchanger (305), and a third-stage heat exchanger (307). Each of the precooling heat exchanger main bodies is respectively a first-stage precooling heat exchanger (304), a second-stage precooling heat exchanger (306), and a third-stage precooling heat exchanger (308). The first-stage precooling heat exchanger (304) is arranged between the first-stage heat exchanger (303) and the second-stage heat exchanger (305). The second-stage precooling heat exchanger (306) is arranged between the second-stage heat exchanger (305) and the third-stage heat exchanger (307). The third-stage precooling heat exchanger (308) is arranged at one end of the third-stage heat exchanger (307) away from the second-stage heat exchanger (305).

4. The rapid cooling device for a helium throttle refrigerator according to claim 3, characterized in that: Inside the vacuum tank (8), there are a first cold shield body (6) and a second cold shield body (7). The second cold shield body (7) is arranged inside the first cold shield body (6). The primary heat exchanger (303) is located in the cavity between the vacuum tank (8) and the first cold shield body (6). The secondary heat exchanger (305) and the primary precooling heat exchanger (304) are located in the cavity between the first cold shield body (6) and the second cold shield body (7). The tertiary heat exchanger (307), the secondary precooling heat exchanger (306), and the tertiary precooling heat exchanger (308) are all located inside the second cold shield body (7).

5. The rapid cooling device of a helium throttling refrigerator according to claim 4, characterized in that: The first cold shield body (6) includes a first cold shield housing and a first cold shield bottom plate. The first cold shield housing is fixed on the first cold shield bottom plate, and the first cold shield bottom plate is connected to the refrigerating end of the precooling machine body (1). The second cold shield body (7) includes a second cold shield housing and a second cold shield bottom plate. The second cold shield housing is fixed on the second cold shield bottom plate, and the second cold shield bottom plate is connected to the refrigerating end of the precooling machine body (1).

6. The rapid cooling device of a helium throttle refrigerator according to claim 5, characterized in that: The materials of the first cold shield bottom plate and the second cold shield bottom plate are both copper. Aluminum foils are installed on the inner walls of the first cold shield housing and the second cold shield housing.

7. The rapid cooling device for a helium throttling refrigerator according to claim 5, characterized in that: The precooling machine body (1) is a secondary precooling machine. The precooling machine body (1) includes a precooling machine primary cold head (101) and a precooling machine secondary cold head (102). The precooling machine primary cold head (101) is connected to the first cold shield bottom plate, and the precooling machine secondary cold head (102) is connected to the second cold shield bottom plate.

8. The rapid cooling device for a helium throttling refrigerator according to claim 3, characterized in that: The intake end of the low-pressure side pipeline (302) is connected to an evaporator (310). A throttling structure (309) is connected between the tertiary precooling heat exchanger (308) and the evaporator (310). The tertiary precooling heat exchanger (308) and the evaporator (310) are connected through a heat bridge (5). The intake end of the precooling pipeline (4) is connected between the tertiary precooling heat exchanger (308) and the throttling structure (309).

9. The rapid cooling device of a helium throttle refrigerator according to claim 1, characterized in that: A stop valve (401) is provided on the precooling pipeline (4).

10. A cooling method for a rapid cooling device of a helium throttle refrigerator, characterized in that, The helium throttling refrigeration machine rapid cooling device according to any one of claims 1-9 includes the following steps: S1. Start the precooling machine body (1) and the compressor unit (2), and open the heat exchange circulation pipeline (3) and the precooling pipeline (4). S2. The gas in the high-pressure side pipeline (301) is cooled in turn after passing through each heat exchanger body and the precooling heat exchanger body. The cooled gas will return to the heat exchange circulation pipeline (3) again through the precooling pipeline (4). S3. When the gas in the heat exchange circulation pipeline (3) is cooled to the working temperature, increase the working power of the compressor unit (2), and close the precooling pipeline (4) so that the gas circulates in the high-pressure side pipeline (301) and the low-pressure side pipeline (302).

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