A dual evaporator low temperature refrigeration cycle system

Abstract

The utility model discloses a dual-evaporator low-temperature refrigeration cycle system, in which a compressor delivers high-temperature and high-pressure gas to a condenser, and the gas enters an evaporator through a liquid storage tank, a drying filter, a heat exchanger, a solenoid valve, an expansion valve, etc. for boiling evaporation and heat exchange. The utility model relates to the field of refrigeration technology, and specifically provides a dual-evaporator low-temperature refrigeration cycle system, which is used to solve the problem in the prior art that the surface temperature of the evaporator is too low after long-term operation, causing frost, thereby affecting the temperature control accuracy.

Description

Technical Field

[0001] The utility model relates to the technical field of refrigeration, in particular to a double-evaporator low-temperature refrigeration cycle system. Background Art

[0002] Most of the current systems use a large-capacity compressor, condenser, evaporator, and expansion valve to form a simple circulation loop. Some systems use dual evaporators, but they are simply operated alternately. Although the set temperature can be reached within a certain period of time, if it is operated for a long time, the surface temperature of the evaporator will be below 0 degrees for a long time. Because the temperature is lower than the dew point temperature, dew will first form, and then frost will form. When the surface frost is too thick, it will affect the heat exchange effect between the evaporator and the surrounding air, thereby affecting the temperature uniformity and precision control. Utility Model Content

[0003] In view of the above-mentioned defects, the utility model provides a dual-evaporator low-temperature refrigeration cycle system, which is used to solve the problem in the prior art that the surface temperature of the evaporator is too low after long-term operation, causing frost and thus affecting the temperature control accuracy.

[0004] In order to solve the above technical problems, the utility model provides the following technical solutions:

[0005] The present invention provides a dual-evaporator low-temperature refrigeration cycle system, including a circuit, a compressor, a condenser and a liquid storage tank, wherein the circuit has a refrigeration pipeline, the compressor is arranged at the position of the refrigeration pipeline, the compressor provides heating and pressurization to transport the high-temperature and high-pressure gaseous refrigerant to the condenser, the condenser is arranged behind the compressor on the circuit, the condenser is used to condense the high-temperature and high-pressure refrigerant into a high-temperature and high-pressure liquid refrigerant, and the liquid storage tank is arranged behind the condenser on the circuit, and is used to store the high-temperature and high-pressure liquid refrigerant;

[0006] Also includes: a heat exchanger, a first throttling device, a second throttling device, a first evaporator and a second evaporator;

[0007] The heat exchanger is arranged behind the liquid storage tank on the loop, and the liquid storage tank is connected to the heat medium inlet of the heat exchanger. The heat medium outlet of the heat exchanger is connected to the first evaporator through the first throttling device and to the second evaporator through the second throttling device. The high-temperature and high-pressure liquid refrigerant is adiabatically throttled by the throttling device to become a low-pressure liquid refrigerant, evaporates in the evaporator and absorbs heat, thereby achieving a refrigeration effect, and the outflowing low-temperature and low-pressure gaseous refrigerant is sucked into the compressor to perform a circulation work.

[0008] The first evaporator and the second evaporator are respectively connected to the refrigerant inlet of the heat exchanger through a check valve, and the refrigerant outlet of the heat exchanger is connected to the compressor.

[0009] Furthermore, the first throttling device includes a first solenoid valve and a first expansion valve which are sequentially connected between the heat exchanger and the first evaporator; the second throttling device includes a second solenoid valve and a second expansion valve which are sequentially connected between the heat exchanger and the second evaporator.

[0010] Furthermore, a fourth solenoid valve is provided between the compressor and the first evaporator, and the fourth solenoid valve is located after the first expansion valve on the loop; a third solenoid valve is provided between the compressor and the second evaporator, and the third solenoid valve is located after the second expansion valve on the loop.

[0011] Furthermore, a first sight glass is provided on the circuit between the first solenoid valve and the first expansion valve, and a second sight glass is provided on the circuit between the second solenoid valve and the second expansion valve.

[0012] Wherein, the first sight glass and the second sight glass are both sight glasses, which are used to observe the running flow state of the refrigerant in the circuit and to indicate the liquid level of the refrigerant and the water content in the refrigerant.

[0013] Furthermore, the system also includes a drying filter, which is arranged between the liquid storage tank of the loop and the heat medium inlet of the heat exchanger. The drying filter can not only remove impurities and moisture in the refrigerant, but also prevent the gaseous refrigerant from entering the expansion valve.

[0014] Furthermore, a regulating valve and a gas-liquid separator are provided in sequence on the circuit between the heat exchanger and the compressor, wherein the regulating valve is a return air pressure regulating valve.

[0015] The beneficial effects achieved by the utility model using the above structure are as follows:

[0016] The present invention solves the problem of temperature control imbalance caused by frosting due to too low surface temperature of the evaporator in low-temperature refrigeration by continuously performing alternating refrigeration and defrosting of two evaporators, and adds a heat exchanger to the system, which can effectively reduce the energy consumption of the compressor and achieve energy saving. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0018] Figure 1 The utility model provides a schematic diagram of the overall structure of a dual-evaporator low-temperature refrigeration cycle system. DETAILED DESCRIPTION

[0019] The technical utility model in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments; based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0020] It should be noted that the words "front", "rear", "left", "right", "up" and "down" used in the following description refer to directions in the drawings, and the words "inside" and "outside" refer to directions toward or away from the geometric center of a specific component, respectively.

[0021] like Figure 1 As shown, the technical utility model adopted by the utility model is as follows: a dual-evaporator low-temperature refrigeration cycle system, including a compressor, a condenser and a liquid storage tank, and also including a circuit with a refrigeration pipeline, wherein the compressor is arranged at the position of the refrigeration pipeline, and the compressor provides heating and pressurization to transport the high-temperature and high-pressure gaseous refrigerant to the condenser, and the condenser is arranged behind the compressor on the circuit. The condenser is used to condense the high-temperature and high-pressure refrigerant into a high-temperature and high-pressure liquid refrigerant, and the liquid storage tank is arranged behind the condenser on the circuit for storing the high-temperature and high-pressure liquid refrigerant.

[0022] This solution also includes a heat exchanger, a first throttling device, a second throttling device, an evaporator 1 and an evaporator 2.

[0023] Among them, the heat exchanger is arranged behind the liquid storage tank on the loop, and the liquid storage tank is connected to the heat medium inlet of the heat exchanger. The heat medium outlet of the heat exchanger is connected to the evaporator 1 through the first throttling device and is connected to the evaporator 2 through the second throttling device. The high-temperature and high-pressure liquid refrigerant is adiabatically throttled by the throttling device to become a low-pressure liquid refrigerant, which evaporates in the evaporator and absorbs heat, thereby achieving a refrigeration effect. The outflowing low-temperature and low-pressure gaseous refrigerant is sucked into the compressor for circulation. The evaporator 1 is connected to the refrigerant inlet of the heat exchanger through the check valve 2, and the evaporator 2 is connected to the refrigerant inlet of the heat exchanger through the check valve 1. The refrigerant outlet of the heat exchanger is connected to the inlet of the compressor.

[0024] As a preferred embodiment:

[0025] The first throttling device includes a solenoid valve 1 and an expansion valve 1 which are sequentially connected between the heat exchanger and the evaporator 1, and a sight glass 1 is arranged on the circuit between the solenoid valve 1 and the expansion valve 1. The second throttling device includes a solenoid valve 2 and a second expansion valve 2 which are sequentially connected between the heat exchanger and the evaporator 2, and a sight glass 2 is arranged on the circuit between the solenoid valve 2 and the expansion valve 2.

[0026] Among them, the sight glass 1 and the sight glass 2 are both sight glasses, which are used to observe the running flow state of the refrigerant in the circuit and to indicate the liquid level of the refrigerant and the water content in the refrigerant.

[0027] Furthermore, a solenoid valve 4 is provided between the compressor and the evaporator 1, and the solenoid valve 4 is located after the expansion valve 1 on the circuit; a solenoid valve 3 is provided between the compressor and the evaporator 2, and the solenoid valve 3 is located after the expansion valve 2 on the circuit.

[0028] As a preferred embodiment:

[0029] The system further comprises a drying filter, which is arranged between the liquid storage tank of the loop and the heat medium inlet of the heat exchanger. The drying filter can not only remove impurities and moisture in the refrigerant, but also prevent the gaseous refrigerant from entering the expansion valve.

[0030] As a preferred embodiment:

[0031] The circuit between the heat exchanger and the compressor is also provided with a regulating valve and a gas-liquid separator in sequence, wherein the regulating valve is a return air pressure regulating valve, and the refrigerant outlet of the heat exchanger is connected to the inlet of the compressor through the regulating valve, the gas-liquid separator in sequence.

[0032] During specific use, when the system starts to run, solenoid valve 1 and solenoid valve 2 are opened, solenoid valve 3 and solenoid valve 4 are closed, and evaporator 1 and evaporator 2 are used together to cool the temperature and quickly reduce the temperature to the set value.

[0033] When the temperature reaches the set value, solenoid valve 1 and solenoid valve 3 are opened, solenoid valve 2 and solenoid valve 4 are closed, and evaporator 1 continues to perform the refrigeration cycle to maintain the temperature control in the space. Part of the high-temperature gas from the compressor directly enters evaporator 2 to ensure that it evaporates at a higher temperature for defrosting operation, and the higher temperature of this part is used to melt the frost on the surface of evaporator 2.

[0034] After a period of time, solenoid valve 1 and solenoid valve 3 are closed, solenoid valve 2 and solenoid valve 4 are opened, and evaporator 1 is defrosted. The two evaporators perform refrigeration and defrosting operations alternately.

[0035] Finally, the gas from the evaporator returns to the compressor through the check valve, heat exchanger, return gas pressure regulating valve and gas-liquid separator to complete the cycle. The role of heat exchange is to use high-temperature liquid and low-temperature gas to exchange heat. This process can increase the temperature of the gas returned to the compressor, thereby reducing the energy consumption of the compressor and achieving the purpose of energy saving.

[0036] The dual-evaporator low-temperature refrigeration circulation system provided in this solution is mainly used in low-temperature plant incubators, seed storage cabinets and other instruments with small spaces that need to provide a low-temperature environment. During operation, the circulation system can effectively suppress the problems of poor heat dissipation and uneven temperature distribution caused by frost on the evaporator surface, which facilitates the long-term stable operation and precise control of the circulation system.

[0037] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, material or apparatus including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, material or apparatus.

[0038] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A dual-evaporator low-temperature refrigeration cycle system, comprising a circuit, a compressor, a condenser and a liquid storage tank, wherein the circuit has a refrigeration pipeline, the compressor is arranged on the circuit, the compressor provides heating and pressurization to transport high-temperature and high-pressure gaseous refrigerant to the condenser, the condenser is arranged behind the compressor on the circuit, the condenser is used to condense the high-temperature and high-pressure refrigerant into a high-temperature and high-pressure liquid refrigerant, and the liquid storage tank is arranged behind the condenser on the circuit and is used to store the high-temperature and high-pressure liquid refrigerant; characterized in that, Also includes: A heat exchanger, a first throttling device, a second throttling device, a first evaporator, and a second evaporator; The heat exchanger is arranged behind the liquid storage tank on the loop, and the liquid storage tank is connected to the heat medium inlet of the heat exchanger. The heat medium outlet of the heat exchanger is connected to the first evaporator through the first throttling device and to the second evaporator through the second throttling device; the first evaporator and the second evaporator are respectively connected to the refrigerant inlet of the heat exchanger through a check valve, and the refrigerant outlet of the heat exchanger is connected to the compressor.

2. A dual-evaporator low-temperature refrigeration cycle system according to claim 1, characterized in that: The first throttling device includes a first solenoid valve and a first expansion valve which are sequentially connected between the heat exchanger and the first evaporator; the second throttling device includes a second solenoid valve and a second expansion valve which are sequentially connected between the heat exchanger and the second evaporator.

3. A dual-evaporator low-temperature refrigeration cycle system according to claim 2, characterized in that: A fourth solenoid valve is provided between the compressor and the first evaporator, and the fourth solenoid valve is located behind the first expansion valve on the loop; a third solenoid valve is provided between the compressor and the second evaporator, and the third solenoid valve is located behind the second expansion valve on the loop.

4. A dual-evaporator low-temperature refrigeration cycle system according to claim 3, characterized in that: A first sight glass is provided on the circuit between the first solenoid valve and the first expansion valve, and a second sight glass is provided on the circuit between the second solenoid valve and the second expansion valve.

5. A dual-evaporator low-temperature refrigeration cycle system according to claim 4, characterized in that: The system further comprises a drying filter, which is arranged between the liquid storage tank of the loop and the heat medium inlet of the heat exchanger.

6. A dual-evaporator low-temperature refrigeration cycle system according to claim 5, characterized in that: A regulating valve and a gas-liquid separator are also arranged in sequence on the circuit between the heat exchanger and the compressor.

7. A dual-evaporator low-temperature refrigeration cycle system according to claim 4, characterized in that: The first sight glass and the second sight glass are both sight glasses, which are used to observe the running flow state of the refrigerant in the circuit and to indicate the liquid level of the refrigerant and the water content in the refrigerant.

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