An ultra-low temperature refrigeration device

Abstract

The application discloses a kind of ultra-low temperature refrigeration equipment, including cabinet, refrigeration system and compressor cabin structure;Compressor cabin structure has bottom wall, front side wall and rear side wall;Condenser is set on bottom wall, front side wall is equipped with air inlet, and the air inlet is communicated with the air inlet side of condenser;Primary compressor, secondary compressor are set side by side on bottom wall;Bottom wall is equipped with heat dissipation hole and baffle, and baffle is located between condenser and primary compressor, secondary compressor;In height direction, top edge of baffle is set to not more than the middle part of primary compressor, secondary compressor;Baffle at least has the guide portion inclined to condenser, and the guide portion is used to isolate the hot airflow of condenser air outlet side and directly blow towards the bottom of primary compressor and secondary compressor, and to guide the hot airflow of condenser air outlet side and discharge downward from heat dissipation hole.The application can effectively reduce the heat load in compressor cabin, improve the cooling speed and refrigeration efficiency of compressor cabin.

Description

Technical Field

[0001] This invention belongs to the field of refrigeration, and specifically relates to an ultra-low temperature refrigeration device. Background Technology

[0002] Cryogenic equipment is a type of storage chamber that can lower the internal temperature to below -80°C and maintain it, for example, for the preservation of pharmaceutical products. Due to the large pressure difference between evaporation and condensation and the limitations of compressors, a single compressor is difficult to meet the requirements. Currently, cryogenic chambers generally use a dual-compressor cascade refrigeration system. The first-stage refrigeration system lowers the refrigerant temperature to around -40°C for heat exchange with the evaporator and condenser, while the second-stage refrigeration system, building upon the first stage, lowers the refrigerant temperature to below -80°C for heat exchange within the cryogenic chamber.

[0003] In practical applications, the first-stage system directly exchanges heat with the surrounding environment, i.e., dissipating heat into the compressor compartment, which leads to an increase in temperature within the compressor compartment and excessive heat load. To improve heat dissipation, existing technologies often use fans; however, the condensation heat guided by the fan still exists within the compressor compartment and circulates there, affecting the temperature of other components, especially the temperature at the bottom of the compressor. Furthermore, the high-temperature gas within the compressor compartment directly enters the condenser from the air inlet side, reducing condenser efficiency. Therefore, effectively reducing the heat load on the compressor compartment is a critical problem that urgently needs to be solved in cryogenic refrigeration equipment. Summary of the Invention

[0004] The main objective of this invention is to provide an ultra-low temperature refrigeration device that can reduce the heat load inside the compressor compartment.

[0005] To achieve the above-mentioned main objectives, the present invention provides an ultra-low temperature refrigeration device, comprising:

[0006] Cabinet, a compartment used for storing items;

[0007] The refrigeration system is used to cool the internal environment of the compartment; the refrigeration system adopts a dual-compressor cascade refrigeration method, including a primary compressor, a secondary compressor, and a condenser;

[0008] The compressor compartment structure has a bottom wall and front and rear side walls located on opposite sides of the bottom wall;

[0009] The condenser is installed on the bottom wall and adjacent to the front side wall. An air inlet is provided on the front side wall, and the air inlet side of the condenser is connected to the air inlet. A cooling fan is provided on the air outlet side of the condenser.

[0010] The primary compressor and the secondary compressor are arranged side by side on the bottom wall and located behind the condenser;

[0011] The bottom wall is provided with heat dissipation holes and a baffle located at the heat dissipation holes. The baffle is located between the condenser and the first-stage compressor and the second-stage compressor. In the height direction, the top edge of the baffle is set to not exceed the middle of the first-stage compressor and the second-stage compressor.

[0012] The baffle has at least a guide portion that is inclined toward the condenser. The guide portion is used to prevent the hot airflow on the condenser outlet side from blowing directly toward the bottom of the primary compressor and the secondary compressor, and to guide the hot airflow on the condenser outlet side to be discharged downward from the heat dissipation hole.

[0013] In one specific embodiment of the present invention, the top edge of the baffle is located at 1 / 5 to 1 / 3 of the overall height of the primary compressor and the secondary compressor in the height direction.

[0014] In one specific embodiment of the present invention, the angle between the guide portion and the bottom wall is 30°-70°.

[0015] In one specific embodiment of the present invention, the angle between the guide portion and the bottom wall is 45°.

[0016] In one specific embodiment of the present invention, the heat dissipation holes are open or mesh-like.

[0017] In one specific embodiment of the present invention, an air guide duct is provided on the air outlet side of the condenser, and a cooling fan is installed inside the air guide duct.

[0018] As a specific embodiment of the present invention, the refrigeration system further includes a decondensation pipe, a primary drying filter, a primary capillary tube, a liquid receiver, a heat exchanger, an oil separator, a secondary drying filter, a secondary capillary tube, and an evaporator;

[0019] The first-stage compressor, condenser, condenser, first-stage dryer filter, first-stage capillary tube, heat exchanger and liquid receiver are connected in sequence to form a first-stage compression system;

[0020] A two-stage compression system is formed by sequentially connecting a two-stage compressor, a condenser, an oil separator, a two-stage dryer filter, a heat exchanger, a two-stage capillary tube, and an evaporator.

[0021] As a specific embodiment of the present invention, the condenser includes a shell, fins, a first pipe, a second pipe, and a third pipe;

[0022] The first, second, and third pipes are installed on the housing;

[0023] The fins are installed on the first, second, and third pipes;

[0024] The inlet end of the first pipeline is connected to the exhaust end of the second-stage compressor, and the outlet end of the first pipeline is connected to the first inlet of the heat exchanger.

[0025] The inlet end of the second pipeline is connected to the exhaust end of the first-stage compressor, and the outlet end of the second pipeline is connected to the inlet of the condenser pipe.

[0026] The inlet end of the third pipeline is connected to the outlet end of the decondenser pipe, and the outlet end of the third pipeline is connected to the second inlet of the heat exchanger.

[0027] In one specific embodiment of the present invention, the first pipeline, the second pipeline, and the third pipeline are arranged in a stacked manner from top to bottom and are independent of each other.

[0028] In one specific embodiment of the present invention, the oil separator is disposed on the bottom wall, wherein the top of the oil separator is configured to be lower than the first pipeline to improve the oil return efficiency.

[0029] The present invention has the following beneficial effects:

[0030] In the ultra-low temperature refrigeration equipment of the present invention, the guide portion on the baffle prevents the hot airflow on the air outlet side of the condenser from blowing directly towards the bottom of the first-stage compressor and the second-stage compressor. At the same time, the heat dissipation holes at the baffle allow the hot airflow to be quickly discharged and dissipated, which helps to reduce the impact of condensation heat on the compressor and other components in the compartment. The present invention can effectively reduce the heat load in the compressor compartment and improve the cooling speed and refrigeration efficiency of the compressor compartment.

[0031] To more clearly illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0032] Figure 1 is a structural diagram of the compressor compartment of the present invention;

[0033] Figure 2 is a top view of the compressor compartment of the present invention;

[0034] Figure 3 is a perspective sectional view of the compressor compartment of the present invention;

[0035] Figure 4 is a longitudinal sectional view of the compressor compartment of the present invention;

[0036] Figure 5 is an exploded view of the condenser of the present invention;

[0037] Figure 6 is a partial structural diagram of the condenser of the present invention;

[0038] Figure 7 is a schematic diagram of the structure of the regenerator of the present invention;

[0039] Figure 8 is a framework diagram of the cryogenic refrigeration system of the present invention;

[0040] Figure 9 is a rendering of the cryogenic refrigeration system of the present invention;

[0041] Figure 10 is a comparison of the effects of traditional cryogenic refrigeration systems. Detailed Implementation

[0042] Numerous specific details are set forth in the following description to provide a thorough understanding of the invention, but the invention can also be implemented in other ways with modifications. Therefore, other possible implementations that can be learned by those skilled in the art based on the embodiments described herein are all within the scope of protection of this invention.

[0043] The cryogenic refrigeration equipment of this invention includes a cabinet, a compressor compartment structure 10, and a refrigeration system 20; wherein, the cabinet defines a compartment for storing items, which is used to place items that need to be cryogenically refrigerated, such as biological pharmaceuticals.

[0044] The refrigeration system 20 is used to cool the internal environment of the compartment; the refrigeration system 20 adopts a dual-compressor cascade refrigeration method, including a primary compression system 21 and a secondary compression system 22; such as Figure 8 As shown, the primary compression system 21 (high temperature stage) includes a primary compressor 211, a decondenser 212, a condenser 30, a primary dryer filter 213, a primary capillary tube 214, a heat exchanger 40, and a liquid receiver 215 connected in sequence; the secondary compression system 22 (low temperature stage) includes a secondary compressor 221, a condenser 30, an oil separator 222, a secondary dryer filter 223, a heat exchanger 40, a secondary capillary tube 224, an evaporator 225, and a regenerator 50; wherein, the heat exchanger 40 is preferably a tubular heat exchanger to save installation space.

[0045] As shown in Figures 1-4, the compressor compartment structure 10 has a bottom wall 11 and front sidewalls 12 and rear sidewalls 13 located on opposite sides of the bottom wall 11. The condenser 30 is mounted on the bottom wall 11 and adjacent to the front sidewall 12. The front sidewall 12 has an air inlet 121, and the air inlet side of the condenser 30 is connected to the air inlet 121. The area of ​​the front sidewall 12, except for the air inlet 121, adopts a closed structure to isolate the hot and cold airflows from each other, so as to prevent the condensation heat in the compressor compartment from leaking out from the front sidewall 12 and directly entering the air inlet side of the condenser 30, which would reduce the efficiency of the condenser 30.

[0046] In an optional embodiment of the present invention, the air inlet 121 of the front sidewall 12 can be configured as a flared shape to facilitate the introduction of external cold air into the condenser 30 for heat dissipation.

[0047] In this embodiment of the invention, the bottom wall 11 is square. The compressor compartment structure 10 also has a left side wall 14 and a right side wall 15 on the other opposite sides of the bottom wall 11. The left side wall 14, the right side wall 15 and the rear side wall 13 are all provided with air outlet grilles to expel the hot air in the compressor compartment as quickly as possible.

[0048] Please refer to Figure 2. The primary compressor 211 and the secondary compressor 221 are arranged side-by-side on the bottom wall 11, located behind the condenser 30. To prevent the hot airflow from the condenser 30's outlet side from affecting the bottom of the compressor, the bottom wall 11 is provided with heat dissipation holes 111 and a baffle 112 located at the heat dissipation holes 111. The baffle 112 is located between the condenser 30 and the primary compressor 211 and the secondary compressor 221. In the height direction, the top edge of the baffle 112 is set not to exceed the middle of the primary compressor 211 and the secondary compressor 221, so as to thermally insulate the lower-temperature area at the bottom of the compressor. Correspondingly, the top of the compressor has a higher temperature, and the airflow formed by the fan in the condenser 30 can also flow in the top area of ​​the compressor to carry away the heat from the top of the compressor.

[0049] Furthermore, the baffle 112 is an inclined plate to provide a guide portion that is inclined toward the condenser 30. The guide portion is used to prevent the hot airflow on the outlet side of the condenser 30 from blowing directly toward the bottom of the primary compressor 211 and the secondary compressor 221, and to guide the hot airflow on the outlet side of the condenser 30 to be discharged downward from the heat dissipation hole 111.

[0050] In this embodiment of the invention, the top edge of the baffle 112 is located at 1 / 5 to 1 / 3 of the overall height of the primary compressor 211 and the secondary compressor 221; for example... Figure 4 As shown, the top edge of the baffle 112 is located, for example, at 1 / 4 of the overall height of the primary compressor 211 and the secondary compressor 221. The angle between the guide portion and the bottom wall 11 is 30°-70°, specifically, for example, 45°, so as to prevent the hot airflow from the outlet side of the condenser 30 from blowing directly towards the compressor, while guiding the hot airflow downwards towards the heat dissipation hole 111.

[0051] In this embodiment of the invention, the heat dissipation hole 111 can be open to reduce exhaust obstruction and allow gas to be discharged quickly; in other embodiments, the heat dissipation hole 111 can also be mesh-shaped.

[0052] The compressor compartment structure 10 in this embodiment of the invention isolates the air inlet side and air outlet side of the condenser 30, which is beneficial to improving the efficiency of the condenser 30; at the same time, the heat dissipation holes 111 and baffles 112 are used to quickly dissipate the condensation heat, which is beneficial to reducing the impact of the condensation heat on the compressor and other components in the compartment.

[0053] The condenser 30 in this embodiment of the invention adopts a three-inlet, three-outlet configuration, such as... Figure 5-6 , Figure 8 As shown, the condenser 30 includes a housing 31, a fan 32, fins 33, and condenser tubes 34. The condenser tubes 34 are mounted on the housing 31, the fan 32 is located on the air outlet side of the housing 31, and the fins 33 are mounted on the condenser tubes 34. The condenser tubes 34 include a first pipe 341, a second pipe 342, and a third pipe 343.

[0054] Specifically, such as Figure 5 As shown, the first pipe 341, the second pipe 342 and the third pipe 343 are stacked from top to bottom and are independent of each other to form a compact structure.

[0055] Please refer to Figure 8. In the condenser 30 of this embodiment, the inlet end of the first pipe 341 is connected to the exhaust end of the second-stage compressor 221 in the second-stage compression system 22, and the outlet end of the first pipe 341 is connected to the first inlet of the heat exchanger 40 to pre-cool the second-stage compression system 22; the inlet end of the second pipe 342 is connected to the exhaust end of the first-stage compressor 211 in the first-stage compression system 21, and the outlet end of the second pipe 342 is connected to the inlet of the decondensation pipe 212 in the first-stage compression system 21; the inlet end of the third pipe 343 is connected to the outlet end of the decondensation pipe 212, and the outlet end of the third pipe 343 is connected to the second inlet of the heat exchanger 40.

[0056] The arrangement of the exhaust from the first-stage compressor 211 entering the second pipe 342 of the condenser 30, then the decondenser pipe 212, then the third pipe 343 returning to the condenser 30, and finally exiting the condenser 30, can reduce the heat load in the compressor compartment and improve the cooling rate of the compressor compartment. If the exhaust from the first-stage compressor 211 directly enters the decondenser pipe 212, the temperature of the door frame will rise, increasing the heat load. Therefore, by using the second pipe 342 of the condenser 30 for pre-cooling of the exhaust from the first-stage compressor 211, then entering the decondenser pipe 212, and finally entering the third pipe 343 of the condenser 30, the increased heat load on the decondenser pipe 212 can be reduced.

[0057] Furthermore, in this embodiment of the invention, the first pipe 341 precools the low-temperature refrigerant R170 to reduce the heat load on the evaporator 225, making it easier for R170 to be subcooled to reach the required low temperature. The first pipe 341, the second pipe 342, and the third pipe 343 are independent of each other. The first pipe 341 carries R170 refrigerant, while the second pipe 342 and the third pipe 343 carry R290 refrigerant to adjust the heat load of the decondensation pipe 212 on the housing. The lengths of the second pipe 342 and the third pipe 343 can be adjusted while keeping the total length of the second pipe 342 and the third pipe 343 constant.

[0058] Specifically, the length of the second pipe 342 directly affects the temperature of the R290 refrigerant entering the condenser pipe 212, thereby affecting the heat load of the condenser pipe 212 on the housing. Therefore, it is preferable to comprehensively consider both the door frame condensation and heat load conditions when determining the length of the second pipe 342. Preferably, the effective length of the first pipe 341 does not exceed the effective length of the second pipe 342, and the effective length of the second pipe 342 does not exceed the effective length of the third pipe 343. This distribution method can meet the pre-cooling requirements of the first pipe 341 for the secondary compression system 22, and also helps to reduce the heat load in the compressor compartment.

[0059] As shown in Figures 3-4, in this embodiment of the invention, the oil separator 222 is disposed on the bottom wall 11, wherein the top of the oil separator 222 is set to be lower than the first pipe 341. Specifically, the secondary compression system 22 adopts a pre-cooling treatment method. The first pipe 341 in the condenser 30 is used to cool the exhaust gas of the cryogenic compressor. At the same time, the oil separator 222 is sunken, that is, lower than the first pipe 341, which is conducive to the recovery of compressor lubricating oil in the condenser 30 and helps the refrigeration process.

[0060] Specifically, the oil separator 222 is preferably positioned slightly below the first pipeline 341. To ensure that the oil separator 222 remains in an effective position below the first pipeline 341 during installation, the height of the oil separator 222 is preferably adjustable. For example, a threaded portion 2221 is provided at the bottom of the oil separator 222, which connects to the bottom wall 11. The height of the oil separator 222 can be adjusted within a certain range during installation.

[0061] As shown in Figures 7-8, the regenerator 50 of this embodiment includes a shell 51 and an intermediate conductive pipe 52. The shell 51 has a regenerating cavity 511, and the intermediate conductive pipe 52 is disposed inside the shell 51 and isolated from the regenerating cavity 511 to provide heat exchange space. Preferably, the shell 51 is cylindrical to provide sufficient heat exchange space, and the intermediate conductive pipe 52 is spiral-shaped to increase the effective length of the intermediate conductive pipe 52 while keeping the length of the shell 51 unchanged, so as to achieve more complete heat exchange.

[0062] Specifically, the first inlet 50a of the regenerator 50 is connected to the second outlet of the heat exchanger 40, the first outlet 50b of the regenerator 50 is connected to the inlet end of the secondary capillary tube 224, the second inlet 50c of the regenerator 50 is connected to the outlet end of the evaporator 225, and the second outlet 50d of the regenerator 50 is connected to the return gas end of the secondary compressor 221.

[0063] In this embodiment of the invention, the two ends of the intermediate conductive pipe 52 form the first inlet 50a and the first outlet 50b of the regenerator 50, respectively. The second inlet 50c and the second outlet 50d of the regenerator 50 are both connected to the regenerating cavity 511. Correspondingly, in other embodiments, depending on the connection method, the two ends of the intermediate conductive pipe 52 can also form the second inlet and the second outlet of the regenerator 50, respectively, and the first inlet and the first outlet of the regenerator 50 are both connected to the regenerating cavity 511.

[0064] The cryogenic refrigeration system of this invention can not only effectively reduce the heat load inside the compressor compartment, but also effectively improve refrigeration efficiency and increase the cooling rate of the compressor compartment; such as Figure 9 As shown, the cryogenic refrigeration system of this invention takes 375.5 minutes to lower the temperature from room temperature to -86°C. Under the same experimental conditions, in contrast, in a conventional cryogenic refrigeration system, the refrigerant is discharged from the secondary compressor and directly enters the oil separator; simultaneously, when the refrigerant is drawn out from the primary compressor, it first enters the condenser pipe, then the condenser, and finally exits the condenser into the primary dryer filter. Figure 10 As shown, a traditional cryogenic refrigeration system takes 436.5 minutes to lower the temperature from room temperature to -86°C. The cryogenic refrigeration system of this invention reduces the cooling time by a full 61 minutes compared to existing cryogenic refrigeration systems, resulting in a significantly faster cooling rate and a substantial improvement in refrigeration efficiency.

[0065] While the present invention has been disclosed above with reference to specific embodiments, these embodiments are not intended to limit the scope of the invention. Any person skilled in the art can make variations / modifications without departing from the scope of the invention; all equivalent variations / modifications made in accordance with the present invention should be covered by the protection scope of the present invention.

Claims

1. An ultra-low temperature refrigeration device, comprising: A cabinet, the cabinet defining a compartment for storing items; A refrigeration system is used to cool the internal environment of the compartment; the refrigeration system adopts a dual-compressor cascade refrigeration method, including a primary compressor, a secondary compressor, and a condenser; The compressor compartment structure has a bottom wall and front and rear side walls located on opposite sides of the bottom wall; Its features are: The condenser is disposed on the bottom wall and adjacent to the front side wall. An air inlet is provided on the front side wall, and the air inlet side of the condenser is connected to the air inlet. A cooling fan is provided on the air outlet side of the condenser. The primary compressor and the secondary compressor are arranged side by side on the bottom wall and located behind the condenser; The bottom wall is provided with heat dissipation holes and a baffle located at the heat dissipation holes. The baffle is located between the condenser and the primary compressor and the secondary compressor. In the height direction, the top edge of the baffle is set to not exceed the middle of the primary compressor and the secondary compressor. The baffle has at least a guide portion that is inclined toward the condenser. The guide portion is used to prevent the hot airflow on the air outlet side of the condenser from blowing directly toward the bottom of the primary compressor and the secondary compressor, and to guide the hot airflow on the air outlet side of the condenser to be discharged downward from the heat dissipation hole.

2. The cryogenic refrigeration equipment as described in claim 1, characterized in that: In the height direction, the top edge of the baffle is located at 1 / 5 to 1 / 3 of the overall height of the primary compressor and the secondary compressor.

3. The cryogenic refrigeration equipment as described in claim 1, characterized in that: The angle between the guide portion and the bottom wall is 30°-70°.

4. The cryogenic refrigeration equipment as described in claim 1, characterized in that: The angle between the guide portion and the bottom wall is 45°.

5. The cryogenic refrigeration equipment as described in claim 1, characterized in that: The heat dissipation holes are open or mesh-like.

6. The cryogenic refrigeration equipment as described in claim 1, characterized in that: The condenser has an air guide duct on its air outlet side, and the cooling fan is installed inside the air guide duct.

7. The cryogenic refrigeration equipment as described in claim 1, characterized in that: The refrigeration system also includes a condenser, a primary dryer filter, a primary capillary tube, a liquid receiver, a heat exchanger, an oil separator, a secondary dryer filter, a secondary capillary tube, and an evaporator; The primary compressor, the decondenser, the condenser, the primary dryer filter, the primary capillary tube, the heat exchanger, and the liquid receiver are sequentially connected to form a primary compression system; The secondary compressor, the condenser, the oil separator, the secondary dryer filter, the heat exchanger, the secondary capillary tube, and the evaporator are sequentially connected to form a secondary compression system.

8. The cryogenic refrigeration equipment as described in claim 7, characterized in that: The condenser includes a shell, fins, a first pipe, a second pipe, and a third pipe; The first pipe, the second pipe, and the third pipe are mounted on the housing; The fins are installed on the first pipe, the second pipe, and the third pipe; The inlet end of the first pipeline is connected to the exhaust end of the secondary compressor, and the outlet end of the first pipeline is connected to the first inlet of the heat exchanger. The inlet end of the second pipeline is connected to the exhaust end of the first-stage compressor, and the outlet end of the second pipeline is connected to the inlet of the decondensation pipe. The inlet end of the third pipeline is connected to the outlet end of the decondensation pipe, and the outlet end of the third pipeline is connected to the second inlet of the heat exchanger.

9. The cryogenic refrigeration equipment as described in claim 8, characterized in that: The first pipeline, the second pipeline, and the third pipeline are arranged in a stacked manner from top to bottom and are independent of each other.

10. The cryogenic refrigeration equipment as described in claim 9, characterized in that: The oil separator is disposed on the bottom wall, wherein the top of the oil separator is configured to be lower than the first pipeline to improve oil return efficiency.

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