Cascade refrigeration device

Abstract

The utility model relates to the technical field of refrigeration equipment, in particular to a cascade refrigeration device which comprises a plate heat exchanger, a high-temperature-stage refrigeration component and a low-temperature-stage refrigeration component, the high-temperature-stage refrigeration component and the low-temperature-stage refrigeration component are connected with the plate heat exchanger and are both filled with refrigerants, and the refrigerants comprise R744; the high-temperature-stage refrigeration component comprises a high-temperature-stage compressor, a high-temperature-stage cooling structure connected with the high-temperature-stage compressor and a high-temperature-stage backflow structure. The low-temperature-stage refrigeration component comprises a low-temperature-stage compressor, a low-temperature-stage cooling structure connected with the low-temperature-stage compressor and a low-temperature-stage backflow structure. Cascade refrigeration can be achieved by arranging the high-temperature-stage refrigeration component and the low-temperature-stage refrigeration component, and the R744 refrigerant is low in GWP value and environmentally friendly. Meanwhile, the high-temperature-stage cooling main path assembly and the high-temperature-stage cooling branch path assembly which are matched with each other can effectively cope with test environments with different temperature requirements, energy is effectively saved, and the refrigeration efficiency is effectively improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of refrigeration equipment, in particular to a cascade refrigeration device. BACKGROUND

[0002] The environmental test chamber is a device for detecting the performance of materials under various temperature environments and testing the heat resistance, cold resistance, dry resistance and moisture resistance of various materials, which is usually configured with a refrigeration system for use.

[0003] The conventional refrigeration system uses traditional refrigerants such as R23, R404A and R448A, and the GWP value of these refrigerants is relatively high. On the one hand, the use of a large amount of refrigerant with a high GWP value will continuously affect the climate and aggravate global warming; on the other hand, in order to obtain a large total temperature difference of refrigeration capacity such as a target temperature of-45℃, the refrigeration system needs to be configured with a refrigeration pipeline with a large pipe diameter to meet the refrigeration requirements, resulting in a large refrigeration system volume and a large energy consumption, insufficient refrigeration efficiency, and increased test cost. CONTENT OF THE UTILITY MODEL

[0004] In order to improve the environmental unfriendliness and insufficient refrigeration efficiency of the conventional refrigeration system in the related art, the utility model provides a cascade refrigeration device.

[0005] A cascade refrigeration device, comprising a plate heat exchanger, a high-temperature level refrigeration component connected with the plate heat exchanger, and a low-temperature level refrigeration component, the high-temperature level refrigeration component and the low-temperature level refrigeration component are filled with refrigerant, and the refrigerant comprises R744;

[0006] The high-temperature level refrigeration component comprises a high-temperature level compressor, a high-temperature level cooling structure connected with the high-temperature level compressor, and a high-temperature level backflow structure; the high-temperature level cooling structure comprises a high-temperature level cooling assembly, the high-temperature level cooling assembly is connected with a high-temperature level cooling main path assembly and a plurality of high-temperature level cooling branch path assemblies, the high-temperature level cooling branch path assemblies are connected with the plate heat exchanger; the high-temperature level cooling main path assembly comprises a high-temperature level refrigeration electromagnetic valve and a high-temperature level evaporator arranged in sequence; the high-temperature level cooling branch path assembly comprises a refrigeration electromagnetic valve and a thermal expansion valve arranged in sequence;

[0007] The low-temperature level refrigeration component comprises a low-temperature level compressor, a low-temperature level cooling structure connected with the low-temperature level compressor, and a low-temperature level backflow structure.

[0008] Further, the high-temperature level cooling assembly comprises a high-temperature level gas cooler, a high-temperature level dry filter and a liquid storage tank connected in sequence to the high-temperature level compressor, and the high-temperature level cooling main path assembly and the high-temperature level cooling branch path assemblies are connected to the liquid storage tank.

[0009] Further, the high-temperature level reflux structure comprises a high-temperature level reflux pressure relief valve, a refrigeration electromagnetic valve, a high-temperature level expansion container and a high-temperature level throttling capillary tube connected to the high-temperature level gas cooler in sequence, and the high-temperature level throttling capillary tube is connected to the high-temperature level compressor.

[0010] Further, the high-temperature level reflux structure further comprises a rapid refrigeration branch, one end of the rapid refrigeration branch is connected to the high-temperature level cooling assembly, the other end of the rapid refrigeration branch is connected to the high-temperature level evaporator, and the rapid refrigeration branch is provided with a refrigeration electromagnetic valve and a stop valve.

[0011] Further, the high-temperature level refrigeration component further comprises a high-temperature level detection structure, the high-temperature level detection structure comprises a high-temperature level exhaust temperature sensor and a high-temperature level exhaust pressure sensor connected to one end of the high-temperature level compressor, and a high-temperature level return gas pressure sensor and a high-temperature level return gas temperature sensor connected to the other end of the high-temperature level compressor.

[0012] Further, the low-temperature level cooling structure comprises a cooling assembly connected to the low-temperature level compressor, the cooling assembly is connected with the plate heat exchanger, and the cooling assembly is connected with a cooling main path assembly and a cooling branch assembly; the cooling main path assembly comprises a refrigeration electromagnetic valve and a low-temperature level evaporator arranged in sequence, and the low-temperature level evaporator is connected to the low-temperature level compressor.

[0013] Further, the low-temperature level reflux structure comprises a safety pressure relief valve, a refrigeration electromagnetic valve, a low-temperature level expansion container and a low-temperature level throttling capillary tube arranged in sequence, and the low-temperature level throttling capillary tube is connected to the low-temperature level compressor.

[0014] Further, the low-temperature level refrigeration component further comprises a low-temperature level detection assembly, the low-temperature level detection assembly comprises an exhaust temperature sensor and an exhaust pressure sensor arranged at one end of the low-temperature level compressor, and a return gas pressure sensor and a return gas temperature sensor arranged at the other end of the low-temperature level compressor.

[0015] The utility model has the following advantages:

[0016] 1. The utility model discloses a kind of cascade refrigeration devices, by setting high-temperature level refrigeration component and low-temperature level refrigeration component and being connected and filled with R744 refrigerant by plate heat exchanger, can realize cascade refrigeration, R744 refrigerant is carbon dioxide, GWP value is low and environment-friendly. Simultaneously, high-temperature level cooling main path assembly and high-temperature level cooling branch assembly of mutual cooperation can effectively respond to different temperature requirements test environment, when test temperature is higher, low-temperature level refrigeration component does not need to be started, only rely on high-temperature level cooling main path assembly can meet environmental temperature requirement, can effectively save energy and improve refrigeration efficiency.

[0017] 2.The compound refrigeration device, through the high-temperature level backflow structure and the low-temperature level backflow structure, the high-temperature level backflow structure and the low-temperature level backflow structure adopt the expansion container and the throttling capillary tube, the refrigerant flow can be conveniently controlled at the same time of pressure relief, so that the compound refrigeration device is accurately controlled.

[0018] 3.The compound refrigeration device, through the high-temperature level detection structure and the low-temperature level detection structure, the exhaust and the back gas state of the refrigeration component can be monitored by the detection structure to know the real-time state of the compound refrigeration device, so that the operator can further operate and control. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0020] Figure 1 It is a structure schematic view of the compound refrigeration device of the embodiment of the present application.

[0021] Figure 2 It is a structure schematic view of the high-temperature level refrigeration component in the embodiment of the present application.

[0022] Figure 3 It is a structure schematic view of the low-temperature level refrigeration component in the embodiment of the present application.

[0023] BRIEF DESCRIPTION OF DRAWINGS

[0024] 1, plate heat exchanger; 2, high-temperature stage refrigeration component; 21, high-temperature stage compressor; 22, high-temperature stage cooling structure; 221, high-temperature stage cooling assembly; 2211, high-temperature stage gas cooler; 2212, high-temperature stage dry filter; 2213, liquid storage tank; 222, high-temperature stage cooling main path assembly; 2221, high-temperature stage refrigeration electromagnetic valve; 2222, high-temperature stage evaporator; 223, high-temperature stage cooling branch path assembly; 224, return branch path; 23, high-temperature stage return structure; 231, high-temperature stage return pressure relief valve; 232, high-temperature stage expansion container; 233, high-temperature stage throttling capillary; 234, rapid refrigeration branch path; 24, high-temperature stage detection structure; 241, high-temperature stage exhaust gas temperature sensor; 242, high-temperature stage exhaust gas pressure sensor; 243, high-temperature stage return gas pressure sensor; 244, high-temperature stage return gas temperature sensor; 245, high-temperature stage gas temperature sensor; 3, low-temperature stage refrigeration component; 31, low-temperature stage compressor; 32, low-temperature stage cooling structure; 3211, low-temperature stage gas cooler; 3221, low-temperature stage evaporator; 33, low-temperature stage return structure; 331, low-temperature stage expansion container; 332, low-temperature stage throttling capillary; 34, low-temperature stage detection assembly. DETAILED DESCRIPTION

[0025] In order to make the above objectives, features and advantages of the present application more apparent, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings. In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be implemented in many different ways than those described herein, and those skilled in the art can make similar improvements without departing from the spirit of the present application, and therefore the present application is not limited to the specific embodiments disclosed below.

[0026] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting", "fixing" and the like should be understood in a broad sense, for example, can be fixed connection, can also be detachable connection, or can be integrated; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0027] In the present application, unless specifically stated and limited otherwise, a first feature "on" or "under" a second feature can be directly in contact with the second feature, or indirectly in contact with the second feature through an intermediate medium. Moreover, a first feature "over", "above" and "on top of" a second feature can be directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature "under", "below" and "underneath" a second feature can be directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0028] It should be noted that when an element is referred to as being "fixed to" or "set to" another element, it can be directly on the other element or there can be an intermediate element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there can be an intermediate element. The terms "vertical", "horizontal", "up", "down", "left", "right" and the like used herein are for illustrative purposes only and are not intended to be the only implementation.

[0029] Referring to Figure 1 , Figure 2 and Figure 3 , a cascade refrigeration device includes a plate heat exchanger 1, a high-temperature stage refrigeration component 2 connected to the plate heat exchanger 1, and a low-temperature stage refrigeration component 3. Both the high-temperature stage refrigeration component 2 and the low-temperature stage refrigeration component 3 are filled with refrigerant, and the refrigerant includes R744. By arranging the high-temperature stage refrigeration component 2 and the low-temperature stage refrigeration component 3 and filling them with R744 refrigerant, on the one hand, the refrigerant can be directly extracted from the environment and can be discharged without pollution, and the low GWP value is environmentally friendly; on the other hand, cascade refrigeration can be achieved, and when the refrigeration requirement is not high, only the high-temperature stage refrigeration component 2 needs to be started to perform refrigeration, thereby consuming less energy and improving the refrigeration efficiency.

[0030] The high-temperature stage refrigeration component 2 comprises a high-temperature stage compressor 21, a high-temperature stage cooling structure 22 connected with the high-temperature stage compressor 21, and a high-temperature stage reflux structure 23. The high-temperature stage cooling structure 22 comprises a high-temperature stage cooling assembly 221, and the high-temperature stage cooling assembly 221 is connected with a high-temperature stage cooling main path assembly 222 and a plurality of high-temperature stage cooling branch path assemblies 223, and the high-temperature stage cooling branch path assemblies 223 are connected with the plate heat exchanger 1. Specifically, the high-temperature stage cooling assembly 221 comprises a high-temperature stage gas cooler 2211, a high-temperature stage dry filter 2212, and a liquid storage tank 2213 connected in sequence to the high-temperature stage compressor 21, and the high-temperature stage cooling main path assembly 222 and the high-temperature stage cooling branch path assemblies 223 are connected to the liquid storage tank 2213. The refrigerant enters the high-temperature stage gas cooler 2211 after passing through the high-temperature stage compressor 21 for cooling, and then passes through the high-temperature stage dry filter 2212 and the liquid storage tank 2213 to enter the high-temperature stage cooling main path assembly 222 and the high-temperature stage cooling branch path assemblies 223.

[0031] The liquid storage tank 2213 is connected with a safety relief valve, and the refrigerant passing through the high-temperature stage cooling assembly 221 passes through the safety relief valve, and the flow rate of the refrigerant entering the high-temperature stage cooling main path assembly 222 and the high-temperature stage cooling branch path assemblies 223 is controlled by the safety relief valve. The high-temperature stage cooling main path assembly 222 comprises a high-temperature stage refrigeration solenoid valve 2221 and a high-temperature stage evaporator 2222 arranged in sequence, and the temperature of the refrigerant entering the high-temperature stage refrigeration solenoid valve 2221 is further reduced. The high-temperature stage evaporator 2222 is connected with a one-way valve, and the refrigerant passing through the high-temperature stage evaporator 2222 returns to the high-temperature stage compressor 21 through the one-way valve.

[0032] The high-temperature stage cooling branch path assembly 223 comprises a refrigeration solenoid valve and a thermal expansion valve arranged in sequence, the temperature of the refrigerant entering the high-temperature stage cooling branch path assembly 223 is further reduced through the refrigeration solenoid valve, and then the refrigerant enters the thermal expansion valve. The thermal expansion valve is used to control the flow rate of the refrigerant, and the refrigerant enters the plate heat exchanger 1 to exchange heat with the low-temperature stage refrigeration component 3. In addition, the high-temperature stage cooling structure 22 further comprises a reflux branch path 224 for balancing pressure, and the reflux branch path 224 is provided with an electronic expansion valve. One end of the reflux branch path 224 is connected to the liquid storage tank 2213, and the other end of the reflux branch path 224 is connected to the high-temperature stage compressor 21. When the pressure in the high-temperature stage refrigeration component 2 is relatively high, the electronic expansion valve is started, so that part of the refrigerant returns to the high-temperature stage compressor 21 through the reflux branch path 224.

[0033] The high-temperature level reflux structure 23 comprises, in sequence, a high-temperature level reflux pressure relief valve 231 connected to the high-temperature level gas cooler 2211, a refrigeration solenoid valve, a high-temperature level expansion container 232 connected with a safety pressure relief valve, and a high-temperature level throttling capillary tube 233 connected to the high-temperature level compressor 21. The part of the refrigerant passing through the high-temperature level gas cooler 2211 will quickly return to the high-temperature level compressor 21 through the high-temperature level reflux structure 23 to balance the gas pressure.

[0034] Meanwhile, the high-temperature level reflux structure 23 further comprises a quick refrigeration branch 234, one end of which is connected to the high-temperature level cooling assembly 221, and the other end of which is connected to the high-temperature level evaporator 2222. The quick refrigeration branch 234 is provided with a refrigeration solenoid valve and a stop valve. When quick refrigeration is needed, the part of the refrigerant passing through the high-temperature level gas cooler 2211 will enter the high-temperature level evaporator 2222 through the quick refrigeration branch 234 to evaporate and absorb heat, so as to quickly reduce the temperature of the environment in which the high-temperature level refrigeration component 2 is located.

[0035] In order to ensure the stable operation of the high-temperature level refrigeration component 2, the high-temperature level refrigeration component 2 further comprises a high-temperature level detection structure 24, which comprises a high-temperature level exhaust gas temperature sensor 241 and a high-temperature level exhaust gas pressure sensor 242 connected to one end of the high-temperature level compressor 21, a high-temperature level return gas pressure sensor 243 and a high-temperature level return gas temperature sensor 244 connected to the other end of the high-temperature level compressor 21, and a high-temperature level gas temperature sensor 245 connected to the high-temperature level gas cooler 2211. By arranging a plurality of temperature and pressure sensors, the operator can easily know the real-time refrigeration state of the high-temperature level refrigeration component 2, so as to accurately and timely control the high-temperature level refrigeration component 2.

[0036] The low-temperature level refrigeration component 3 comprises a low-temperature level compressor 31, a low-temperature level cooling structure 32 connected to the low-temperature level compressor 31, and a low-temperature level reflux structure 33. The low-temperature level cooling structure 32 comprises a cooling assembly connected to the low-temperature level compressor 31, which is connected to a cooling main path assembly and a cooling branch path assembly after being connected to the plate heat exchanger 1. Specifically, the cooling assembly comprises a low-temperature level gas cooler 3211 connected to the low-temperature level compressor 31 and a drying filter connected to the plate heat exchanger 1. The refrigerant passing through the low-temperature level gas cooler 3211 and the dryer enters the plate heat exchanger 1 to exchange heat with the high-temperature level refrigeration component 2, and then enters the cooling main path assembly and the cooling branch path assembly after further reducing the temperature.

[0037] The cooling main branch assembly comprises a refrigeration solenoid valve and a low-temperature stage evaporator 3221 arranged in sequence, and the low-temperature stage evaporator 3221 is connected to the low-temperature stage compressor 31. The cooling branch assembly comprises a refrigeration solenoid valve and a thermal expansion valve arranged in sequence. After heat exchange, part of the refrigerant enters the low-temperature stage evaporator 3221, and the refrigerant is evaporated to absorb heat, so that the temperature of the low-temperature refrigeration component is reduced, and the temperature range of the low-temperature refrigeration component can reach -45°

[0038] The low-temperature stage reflux structure 33 comprises a safety relief valve, a refrigeration solenoid valve, a low-temperature stage expansion container 331 and a low-temperature stage throttling capillary tube 332 arranged in sequence, and the low-temperature stage throttling capillary tube 332 is connected to the low-temperature stage compressor 31. Part of the refrigerant passing through the drying filter will enter the low-temperature stage reflux structure 33 and quickly return to the low-temperature stage compressor 31 to balance the pressure. At the same time, the low-temperature stage reflux structure 33 also comprises a reflux branch, and the reflux branch is provided with a refrigeration solenoid valve and a stop valve. By opening the stop valve of the reflux branch, the refrigerant can be returned, so as to further balance the pressure.

[0039] Similar to the high-temperature stage refrigeration component 2, the low-temperature stage refrigeration component 3 also comprises a low-temperature stage detection assembly 34, which comprises an exhaust temperature sensor and an exhaust pressure sensor arranged at one end of the low-temperature stage compressor 31, and a return gas pressure sensor and a return gas temperature sensor arranged at the other end of the low-temperature stage compressor 31. Through the temperature and pressure sensors, the state of the low-temperature stage refrigeration component 3 can be monitored in real time to facilitate control.

[0040] The technical features of the above-mentioned embodiments can be combined in any way. In order to make the description simple, all possible combinations of the technical features in the above-mentioned embodiments are not described, but as long as the combinations of the technical features do not exist, they should be considered as the scope of the description.

[0041] The above-mentioned embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it should not be understood as limiting the scope of the patent application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A cascade refrigeration apparatus, characterized by comprising: The application relates to a refrigeration system, which comprises a plate heat exchanger (1), a high-temperature stage refrigeration component (2) connected with the plate heat exchanger (1), and a low-temperature stage refrigeration component (3), wherein the high-temperature stage refrigeration component (2) and the low-temperature stage refrigeration component (3) are filled with refrigerant, and the refrigerant comprises R744. The high-temperature stage refrigeration component (2) comprises a high-temperature stage compressor (21), a high-temperature stage cooling structure (22) connected with the high-temperature stage compressor (21), and a high-temperature stage backflow structure (23); the high-temperature stage cooling structure (22) comprises a high-temperature stage cooling assembly (221), the high-temperature stage cooling assembly (221) is connected with a high-temperature stage cooling main path assembly (222) and a plurality of high-temperature stage cooling branch path assemblies (223), the high-temperature stage cooling branch path assemblies (223) are connected with the plate heat exchanger (1); the high-temperature stage cooling main path assembly (222) comprises a high-temperature stage refrigeration electromagnetic valve (2221) and a high-temperature stage evaporator (2222) arranged in sequence; the high-temperature stage cooling branch path assembly (223) comprises a refrigeration electromagnetic valve and a thermal expansion valve arranged in sequence. The low-temperature stage refrigeration component (3) comprises a low-temperature stage compressor (31), a low-temperature stage cooling structure (32) connected with the low-temperature stage compressor (31), and a low-temperature stage backflow structure (33).

2. A cascade refrigeration apparatus according to claim 1, characterized in that The high-temperature stage cooling assembly (221) comprises a high-temperature stage gas cooler (2211), a high-temperature stage dry filter (2212) and a liquid storage tank (2213) connected in sequence to the high-temperature stage compressor (21), and the high-temperature stage cooling main path assembly (222) and the high-temperature stage cooling branch path assembly (223) are connected to the liquid storage tank (2213).

3. A cascade refrigeration apparatus according to claim 2, wherein The high-temperature stage backflow structure (23) comprises a high-temperature stage backflow pressure relief valve (231), a refrigeration electromagnetic valve, a high-temperature stage expansion container (232) and a high-temperature stage throttling capillary tube (233) connected in sequence to the high-temperature stage gas cooler (2211), and the high-temperature stage throttling capillary tube (233) is connected to the high-temperature stage compressor (21).

4. A cascade refrigeration apparatus according to claim 3, wherein The high-temperature stage backflow structure (23) further comprises a rapid refrigeration branch path (234), one end of the rapid refrigeration branch path (234) is connected to the high-temperature stage cooling assembly (221), the other end of the rapid refrigeration branch path (234) is connected to the high-temperature stage evaporator (2222), and the rapid refrigeration branch path (234) is provided with a refrigeration electromagnetic valve and a stop valve.

5. A cascade refrigeration apparatus according to any one of claims 1 to 4, characterized in that The high-temperature stage refrigeration component (2) further comprises a high-temperature stage detection structure (24), the high-temperature stage detection structure (24) comprises a high-temperature stage exhaust gas temperature sensor (241) connected to one end of the high-temperature stage compressor (21), a high-temperature stage exhaust gas pressure sensor (242), a high-temperature stage back gas pressure sensor (243) connected to the other end of the high-temperature stage compressor (21) and a high-temperature stage back gas temperature sensor (244).

6. A cascade refrigeration apparatus according to claim 1, wherein The low-temperature stage cooling structure (32) comprises a cooling assembly connected with the low-temperature stage compressor (31), and the cooling assembly is connected with the plate heat exchanger (1), and a cooling main path assembly and a cooling branch path assembly are further connected after the connection; the cooling main path assembly comprises a refrigeration electromagnetic valve and a low-temperature stage evaporator (3221) arranged in sequence, and the low-temperature stage evaporator (3221) is connected to the low-temperature stage compressor (31).

7. A cascade refrigeration apparatus according to claim 6, wherein The low-temperature stage reflux structure (33) comprises a safety pressure relief valve, a refrigeration electromagnetic valve, a low-temperature stage expansion container (331) and a low-temperature stage throttling capillary tube (332) arranged in sequence, and the low-temperature stage throttling capillary tube (332) is connected to the low-temperature stage compressor (31).

8. A cascade refrigeration apparatus according to claim 6, wherein The low-temperature stage refrigeration component (3) further comprises a low-temperature stage detection assembly (34), and the low-temperature stage detection assembly (34) comprises an exhaust temperature sensor and an exhaust pressure sensor arranged at one end of the low-temperature stage compressor (31), and a return gas pressure sensor and a return gas temperature sensor arranged at the other end of the low-temperature stage compressor (31).

Images