WO2024198322A1 - Air conditioning system, air conditioning unit, and control method - Google Patents

Abstract

The present invention provides an air conditioning system, an air conditioning unit, and a control method. The air conditioning system comprises: a compressor, a four-way valve, an outdoor heat exchanger, a throttling assembly, and an indoor heat exchange module which are sequentially connected to form a refrigerant circulation loop; the refrigerant circulation loop is provided with a gas-liquid separator used for temporarily storing a liquid refrigerant, the gas-liquid separator is connected to the indoor heat exchange module and the four-way valve, and the gas-liquid separator is connected to an air suction side or an air discharge side of the compressor by means of switching of the four-way valve; and the bottom of an inner cavity of the gas-liquid separator is communicated with an inlet side of the indoor heat exchange module under a heating cycle by means of a liquid discharging pipeline. According to the present invention, the liquid discharging pipeline is communicated between the bottom of the inner cavity of the gas-liquid separator and the inlet side of the indoor heat exchange module under the heating cycle, so that the liquid refrigerant at the bottom of the inner cavity of the gas-liquid separator is discharged from the liquid discharging pipeline, and under the high-air-pressure effect of a gas refrigerant, the liquid discharging pipeline of the gas-liquid separator has enough power for liquid discharging.

Description

Air conditioning system, air conditioning unit and control method

This disclosure is based on the application with CN application number 202310320016.X and application date March 29, 2023 The disclosure of the CN application is hereby incorporated into the present application as a whole, and claims its priority.

Technical Field

The present disclosure relates to the technical field of air conditioning, and in particular to an air conditioning system, an air conditioning unit and a control method.

Background Art

At present, when the air conditioning system is in heating operation, the outdoor side is the evaporation side. As the refrigerant evaporates and absorbs heat, the temperature of the outdoor side pipeline decreases, and the surface of the outdoor heat exchanger gradually frosts. When the air conditioning system is in defrosting operation, a four-way valve is generally used to switch the refrigerant flow direction to the refrigeration cycle, and the high-temperature gaseous refrigerant is used to enter the outdoor heat exchanger. The frost layer on the surface of the outdoor heat exchanger absorbs heat to achieve defrosting. After defrosting, the four-way valve switches the refrigerant flow direction to the heating cycle, and the air conditioning system resumes the heating mode. The air conditioning system has the problem of large differences in the refrigerant circulation volume required in the cooling mode and the heating mode. Under the refrigerant circulation volume that meets the requirements of the heating mode, the refrigerant circulation volume in the cooling mode is too much, resulting in a large high and low pressure difference in the system, a large compressor load, and poor energy saving effect. For this reason, some air conditioning systems achieve gas-liquid regulation in different modes by setting a gas-liquid separator, so that the excess liquid refrigerant is temporarily stored in the gas-liquid separator. However, since a large amount of liquid refrigerant in the gas-liquid separator after defrosting cannot be transferred in time, the heating effect after defrosting is slow and the heat exchange efficiency is poor.

Summary of the invention

In order to alleviate the problem of refrigerant accumulation in the outdoor heat exchanger during the defrosting process of the air-conditioning system, resulting in slow heating effect after defrosting, the disclosed embodiment proposes an air-conditioning system, air-conditioning unit and control method for realizing liquid refrigerant transfer. The air-conditioning system can rely on the high-temperature and high-pressure refrigerant of the exhaust to vaporize the liquid refrigerant in the gas-liquid separator and bring it into the heating cycle when the defrosting is completed and switched to the heating cycle, thereby achieving the effect of rapid heating after defrosting.

One aspect of an embodiment of the present disclosure provides an air-conditioning system, comprising: a compressor, a four-way valve, an outdoor heat exchanger, a throttling component and an indoor heat exchange module which are connected in sequence to form a refrigerant circulation loop; the refrigerant circulation loop is provided with a gas-liquid separator for temporarily storing liquid refrigerant, the gas-liquid separator connects the indoor heat exchange module and the four-way valve, and the gas-liquid separator is connected to the suction side or the exhaust side of the compressor through the switching of the four-way valve; the bottom of the inner cavity of the gas-liquid separator is connected to the indoor heat exchange module under the heating cycle through a drain pipe The inlet side is connected.

In certain embodiments, a first end of the gas-liquid separator is connected to the four-way valve, and a second end of the gas-liquid separator is connected to an outlet side of the indoor heat exchange module under a refrigeration cycle.

In certain embodiments, the liquid discharge pipeline is connected to a first pipeline between the second end of the gas-liquid separator and the indoor heat exchange module.

In certain embodiments, the connection position between the liquid discharge pipeline and the first pipeline is not higher than the height of the pipe opening of the liquid discharge pipeline in the gas-liquid separator.

In some embodiments, the first end of the gas-liquid separator is located at the top of the inner cavity of the gas-liquid separator, and the first end of the gas-liquid separator is the first end of a U-shaped tube located in the inner cavity of the gas-liquid separator, and the tube mouth of the second end of the U-shaped tube faces upward close to the top position of the inner cavity of the gas-liquid separator.

In some embodiments, the second end of the gas-liquid separator is located at the top of the inner cavity of the gas-liquid separator, and the pipe mouth of the second end of the gas-liquid separator is located in the inner cavity of the gas-liquid separator and is opposite to the pipe mouth of the second end of the U-shaped tube and is inclined to one side.

In certain embodiments, an oil return hole is provided at the bottom of the U-shaped tube.

In certain embodiments, a control valve is provided on the liquid discharge pipeline.

In another aspect of the embodiments of the present disclosure, an air-conditioning unit is provided, comprising the above-mentioned air-conditioning system.

In another aspect of the embodiment of the present disclosure, a control method is also provided, which is applied to the above-mentioned air-conditioning system; the control method includes: after the refrigerant circulation loop runs a defrost cycle, determining whether there is a heating demand, and if so, opening the control valve and switching the air-conditioning system to a heating cycle, so that the liquid refrigerant in the gas-liquid separator is discharged from the drain pipeline.

Based on the above description of the embodiments of the present disclosure, the embodiments of the present disclosure have at least the following beneficial effects:

By connecting the drain pipe between the bottom of the inner cavity of the gas-liquid separator and the inlet side of the indoor heat exchange module in the heating cycle, the liquid refrigerant at the bottom of the inner cavity of the gas-liquid separator is discharged from the drain pipe. Under the action of the high gas pressure of the gas refrigerant, the drain pipe of the gas-liquid separator has sufficient power to discharge the liquid.

The liquid refrigerant is allowed to enter the gas refrigerant pipeline, accelerating the vaporization of the liquid refrigerant, thereby accelerating the vaporization speed of the entire liquid refrigerant in the air-conditioning system, shortening the time for the liquid refrigerant to be discharged from the vapor-liquid separator, reducing the time for the heating capacity to recover to the maximum output after defrosting, and improving the heating capacity.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings described herein are used to provide a further understanding of the present disclosure and constitute a part of this application. The exemplary embodiments and descriptions disclosed herein are used to explain the present disclosure and do not constitute improper limitations on the present disclosure. In the accompanying drawings:

FIG1 is a schematic diagram of an air conditioning system according to a first embodiment.

FIG. 2 is a schematic diagram of the air conditioning system of the first embodiment when operating in a cooling or defrosting mode.

FIG3 is a schematic diagram of the air conditioning system of the first embodiment when operating in a heating mode.

FIG. 4 is a schematic structural diagram of the gas-liquid separator portion of the first embodiment.

FIG5 is a schematic diagram of an air conditioning system according to a second embodiment.

FIG6 is a schematic diagram of the air conditioning system of the second embodiment when operating in the cooling or defrosting mode.

FIG. 7 is a schematic diagram of the air conditioning system of the second embodiment when operating in the heating mode.

DETAILED DESCRIPTION

The technical solutions in the embodiments will be described clearly and completely below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

In the description of the present disclosure, it should be understood that the terms "center", "longitudinal", "lateral", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the scope of protection of the present disclosure.

Embodiment 1

As shown in Figure 1, the air-conditioning system proposed in the embodiment of the present disclosure can alleviate the problem of liquid refrigerant accumulating in the gas-liquid separator after defrosting. When the defrosting is completed and the mode is switched to the heating mode, the liquid refrigerant accumulated in the gas-liquid separator is vaporized by the high-temperature and high-pressure refrigerant discharged by the compressor and brought into the heating cycle, thereby achieving the effect of rapid heating after defrosting.

Specifically, the air conditioning system includes: a compressor 1, a four-way valve 2, an outdoor heat exchanger 3, an outdoor fan 4, a throttling component 5, and an indoor heat exchange module located between a second pipeline 6 and a first pipeline 7, which are sequentially connected to form a refrigerant circulation loop; the refrigerant circulation loop is provided with a gas-liquid separator 8 for temporarily storing liquid refrigerant, the gas-liquid separator 8 is connected to the indoor heat exchange module and the four-way valve 2, and the gas-liquid separator 8 is connected to the indoor heat exchange module and the four-way valve 2 by the cut-off of the four-way valve 2. The gas-liquid separator 8 is connected to the suction side or the exhaust side of the compressor 1. As shown in Figure 4, the bottom of the inner cavity of the gas-liquid separator 8 is connected to the inlet side of the indoor heat exchange module in the heating cycle through the drain pipe 103. The first end 101 of the gas-liquid separator 8 is connected to the four-way valve 2, and the second end 102 of the gas-liquid separator 8 is connected to the outlet side of the indoor heat exchange module in the refrigeration cycle (the inlet side of the indoor heat exchange module in the heating cycle). The drain pipe 103 is connected to the first pipe 7 between the second end 102 of the gas-liquid separator 8 and the indoor heat exchange module, and the first pipe 7 is the air pipe.

Referring to Figure 2, when the refrigerant circulation loop operates in a refrigeration cycle or a defrost cycle, the gas-liquid separator 8 is connected to the suction side of the compressor 1, and the refrigerant is sent back to the suction side of the compressor 1 through the gas-liquid separator 8. The liquid refrigerant is stored by the gas-liquid separator 8 to prevent the liquid refrigerant from accumulating in the outdoor heat exchanger 3; specifically, as shown in Figure 2, when the air conditioner is in the refrigeration or defrost mode, the refrigerant is discharged from the compressor 1, enters the outdoor heat exchanger 3 for condensation and heat exchange through the four-way valve 2, enters the indoor side for heat exchange through the heating electronic expansion valve and the second pipeline 6, and then enters the gas-liquid separator 8 through the first pipeline 7 (gas pipe) from the second end 102 of the gas-liquid separator 8 and the discharge pipeline 103 of the gas-liquid separator 8, flows out from the first end 101 of the gas-liquid separator 8, and returns to the suction side of the compressor 1 through the four-way valve 2.

Referring to FIG3 , after defrosting is completed and switched to the heating cycle, the first end 101 of the gas-liquid separator 8 enters the high-temperature and high-pressure gas refrigerant, and the gas refrigerant not only enters the first pipeline 7 from the second end 102 of the gas-liquid separator 8, but also causes the liquid refrigerant at the bottom of the inner cavity of the gas-liquid separator 8 to be discharged from the drain pipeline 103 into the first pipeline 7. Under the high pressure of the gas refrigerant, the drain pipeline 103 of the gas-liquid separator 8 has sufficient power to drain. The gas refrigerant in the first pipeline 7 accelerates the vaporization of the liquid refrigerant entering, thereby accelerating the vaporization speed of the liquid refrigerant in the air-conditioning system as a whole, shortening the time for the liquid refrigerant in the gas-liquid separator 8 to be discharged, reducing the time for the heating capacity to recover to the maximum output after defrosting, and improving the heating capacity.

When the refrigerant circulation loop is switched to the heating cycle, the gas-liquid separator 8 is connected to the exhaust side of the compressor 1, and the high-temperature refrigerant discharged from the compressor 1 passes through the gas-liquid separator 8, and the liquid refrigerant in the gas-liquid separator 8 is heated and gasified by the high-temperature refrigerant, and then brought into the heating cycle, so as to achieve the effect of rapid heating after defrosting. Specifically, as shown in Figure 3, after defrosting is completed, the air conditioner is switched to the heating mode, and the refrigerant is discharged from the compressor 1, passes through the four-way valve 2, enters the gas-liquid separator 8 from the first end 101 of the gas-liquid separator 8, flows out from the second end 102 of the gas-liquid separator 8 and the discharge pipeline 103 of the gas-liquid separator 8, enters the indoor side through the first pipeline 7 for heat exchange, and returns to the outdoor heat exchanger 3 through the second pipeline 6 and the heating electronic expansion valve for evaporation and heat exchange, and returns to the suction side of the compressor 1 through the four-way valve 2.

4 , the connection position 104 between the drain pipe 103 and the first pipe 7 is not higher than the pipe opening height of the drain pipe 103 in the gas-liquid separator 8 , so as to simultaneously utilize the gravitational potential energy of the liquid refrigerant to accelerate the drainage.

The first end 101 of the gas-liquid separator is located at the top of the inner cavity of the gas-liquid separator 8, and the first end 101 is connected to the first end of a U-shaped tube located in the inner cavity of the gas-liquid separator 8. The second end of the U-shaped tube has an opening facing upward and close to the top of the inner cavity of the gas-liquid separator 8, so that the gas can enter and exit from the top of the inner cavity of the gas-liquid separator.

The second end 102 of the gas-liquid separator 8 is located at the top of the inner cavity of the gas-liquid separator 8. The second end 102 of the gas-liquid separator 8 is located at the pipe mouth of the inner cavity of the gas-liquid separator 8 and is opposite to the pipe mouth of the second end of the U-shaped tube up and down and inclined to one side to avoid the two ends being directly opposite to each other, so as to better separate the gas and liquid.

The bottom of the U-shaped tube is provided with an oil return hole 9, so that the lubricating oil mixed in the refrigerant returns to the compressor 1, thereby ensuring the oil amount in the compressor 1 and the oil supply to the scroll part.

The air conditioning system is applicable to various air conditioning units, thereby accelerating the vaporization speed of the overall liquid refrigerant of the air conditioning system, shortening the time for the liquid refrigerant to be discharged from the vapor-liquid separator, and reducing the time for the heating capacity to recover to the maximum output after defrosting.

Embodiment 2

As shown in FIGS. 5 , 6 and 7 , the difference between the air conditioning system provided in the second embodiment and the air conditioning system provided in the first embodiment is that a control valve 10 is provided on the drain pipe 103 to control the on-off or flow rate of the drain pipe 103 .

The control method includes: after the refrigerant circulation loop runs a defrost cycle, determining whether there is a heating demand, and if so, opening the control valve 10 and switching the air-conditioning system to a heating cycle, so that the liquid refrigerant in the gas-liquid separator 8 is discharged from the drain pipe 103.

During the refrigeration cycle, the control valve 10 can be selectively opened or closed.

Based on the above-mentioned embodiments of the present disclosure, in the absence of explicit negation or conflict, the technical features of one embodiment may be beneficially combined with one or more other embodiments.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present disclosure rather than to limit it. Although the present disclosure has been described in detail with reference to the preferred embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present disclosure can still be modified or some technical features can be replaced by equivalents without departing from the spirit of the technical solution of the present disclosure, which should be included in the scope of the technical solution for protection of the present disclosure.

Claims (10)

An air conditioning system comprises: a compressor, a four-way valve, an outdoor heat exchanger, a throttling assembly and an indoor heat exchange module which are connected in sequence to form a refrigerant circulation loop; the refrigerant circulation loop is provided with a gas-liquid separator for temporarily storing liquid refrigerant, the gas-liquid separator is connected to the indoor heat exchange module and the four-way valve, and the gas-liquid separator is connected to the suction side or the exhaust side of the compressor through the switching of the four-way valve; the bottom of the inner cavity of the gas-liquid separator is connected to the inlet side of the indoor heat exchange module in the heating cycle through a drain pipeline. The air conditioning system according to claim 1, wherein the first end of the gas-liquid separator is connected to the four-way valve, and the second end of the gas-liquid separator is connected to the outlet side of the indoor heat exchange module under the refrigeration cycle. The air conditioning system according to claim 2, wherein the drain pipeline is connected to the first pipeline between the second end of the gas-liquid separator and the indoor heat exchange module. The air conditioning system according to claim 3, wherein the connection position between the drain pipeline and the first pipeline is not higher than the height of the pipe opening of the drain pipeline in the gas-liquid separator. An air conditioning system according to any one of claims 1 to 4, wherein the first end of the vapor-liquid separator is located at the top of the inner cavity of the gas-liquid separator, the first end of the vapor-liquid separator is the first end of a U-shaped tube located in the inner cavity of the gas-liquid separator, and the pipe opening of the second end of the U-shaped tube faces upward and is close to the top position of the inner cavity of the gas-liquid separator. The air conditioning system according to claim 5, wherein the second end of the gas-liquid separator is located at the top of the inner cavity of the gas-liquid separator, and the second end of the gas-liquid separator is located at the pipe opening of the inner cavity of the gas-liquid separator and is opposite to the pipe opening of the second end of the U-shaped tube and is inclined toward one side. The air conditioning system according to claim 5 or 6, wherein an oil return hole is provided at the bottom of the U-shaped tube. The air conditioning system according to any one of claims 1 to 7, wherein a control valve is provided on the drain pipe. An air conditioning unit, comprising the air conditioning system according to any one of claims 1 to 8. A control method, which is applied to the air-conditioning system according to claim 8; the control method comprises: after the refrigerant circulation loop runs a defrost cycle, determining whether there is a heating demand, and if so, opening the control valve and switching the air-conditioning system to a heating cycle, so that the liquid refrigerant in the gas-liquid separator is discharged from the drain pipeline.