KR102243376B1 - Air conditioning system - Google Patents

Abstract

The present invention relates to an air conditioning system. An air conditioning system according to an embodiment of the present invention includes a compressor that compresses a refrigerant at high temperature and high pressure, a compressor discharge pipe through which the refrigerant discharged from the compressor flows, and separates the refrigerant into a gas phase refrigerant and a liquid refrigerant, and separates the gas phase refrigerant into the compressor. A compressor inlet pipe through which the refrigerant flowing into the compressor flows, and a bypass pipe connecting the compressor discharge pipe and the compressor inlet pipe, and passing through the accumulator by connecting the accumulator supplied to the compressor. do.

Description

Air conditioning system {AIR CONDITIONING SYSTEM}

The present invention relates to an air conditioning system.

The air conditioning system is a system for maintaining the air in a predetermined space in the most suitable state according to the use and purpose. In general, an air conditioning system includes a compressor, a condenser, an expansion device, and an evaporator, and a refrigerant cycle for compressing, condensing, expanding, and evaporating the refrigerant is driven to cool or heat the predetermined space.

In this case, the predetermined space may be proposed in various ways depending on the location where the air conditioning system is used. For example, when the air conditioning system is used in a home or office, the predetermined space may be an indoor space of a house or building. In addition, when the air conditioning system is used in a vehicle, the predetermined space may be a boarding space for a person to board.

The air conditioning system includes an indoor heat exchanger and an outdoor heat exchanger functioning as the condenser or the evaporator. The indoor heat exchanger is disposed in an indoor unit disposed in the predetermined space, and the outdoor heat exchanger is disposed outside the predetermined space.

In this case, the indoor heat exchanger or the outdoor heat exchanger may not function properly, and a phenomenon in which refrigerant is accumulated may occur. For example, when the air conditioning system is operated in a heating mode, the outdoor temperature is very low, so that the outdoor heat exchanger does not properly function as an evaporator, and refrigerant may accumulate.

Various technologies have been developed to prevent the accumulation of such refrigerants, and information on prior literature related thereto is as follows.

(1) 1st Prior Document: Registered Patent 10-1283743 (registered on July 02, 2013), a heat pump system that improves heating performance using waste heat

The first prior document describes a technique of vaporizing a refrigerant accumulated in a low pressure cycle by using waste heat generated from an external device. Specifically, waste heat generated from a vehicle engine or the like is supplied to the outdoor heat exchanger to prevent performance degradation of the outdoor heat exchanger due to a low external temperature.

(2) 2nd Prior Document: Registered Patent 10-0569833 (registered on April 04, 2006), Flash tank of two-stage compression heat pump system with cold and hot heat manufacturing system

The second prior document describes a technique for controlling the dryness and circulation amount of a refrigerant by installing a flash tank in a low-pressure and high-pressure cycle of a heat pump performing two-stage compression.

According to the conventional air conditioning system according to such prior literature, there are the following problems.

(1) It is necessary to install an additional device to prevent the accumulation of refrigerant. Specifically, in the case of the first prior document, another device for generating external waste heat is required, and in the case of the second prior document, a flash tank is required. It can be used only when such a device is connected, and there is a problem in that it takes time and cost according to the installation.

(2) In addition, in the case of the first prior document, there is a problem in that it is difficult to ensure improvement of the performance of the air conditioning system because it is difficult to control the supply of waste heat.

(3) In addition, in the case of the second prior document, there is a problem in that proper control is difficult because there is a limit of the flash tank capacity.

The present invention has been proposed to solve such a problem, and an object of the present invention is to provide an air conditioning system that prevents accumulation of refrigerant by using a heat source of the system itself so that proper performance can be maintained regardless of the external environment.

Another object of the present invention is to provide an air conditioning system that prevents accumulation of refrigerant by evaporating refrigerant by connecting a pipe to an accumulator without installing an additional device.

An air conditioning system according to an embodiment of the present invention includes a compressor that compresses a refrigerant at high temperature and high pressure, a compressor discharge pipe through which the refrigerant discharged from the compressor flows, and separates the refrigerant into a gas phase refrigerant and a liquid refrigerant, and separates the gas phase refrigerant into the compressor. A compressor inlet pipe through which the refrigerant flowing into the compressor flows, and a bypass pipe connecting the compressor discharge pipe and the compressor inlet pipe, and passing through the accumulator by connecting the accumulator supplied to the compressor. do.

The bypass pipe includes a first bypass pipe extending from the compressor discharge pipe to the accumulator, a second bypass pipe disposed inside the accumulator, and a third bypass pipe extending from the accumulator toward the compressor inlet pipe. May be included.

A bypass valve for opening and closing the flow of refrigerant may be installed in the first bypass pipe.

The second bypass pipe may be bent and installed inside the accumulator.

The second bypass pipe may be disposed at a lower side of the accumulator in which the liquid refrigerant is accumulated so that the liquid refrigerant accumulated in the accumulator may be vaporized through heat exchange with the second bypass pipe.

In the third bypass pipe, a bypass expansion valve for expanding the flowing refrigerant may be installed.

An outdoor heat exchanger for exchanging refrigerant with outdoor air, an indoor heat exchanger for exchanging refrigerant with indoor air, an expansion valve installed between the indoor heat exchanger and the outdoor heat exchanger, and a refrigerant passing through the outdoor heat exchanger or the outdoor heat exchanger An injection pipe for injecting into the compressor may be further included.

The bypass pipe includes a first bypass pipe extending from the compressor discharge pipe to the accumulator, a second bypass pipe disposed inside the accumulator, and a third bypass pipe extending from the accumulator to the bypass branch. And a fourth bypass pipe extending from the bypass branch to the compressor inlet pipe and a fifth bypass pipe extending from the bypass branch to the injection pipe.

A first bypass valve for opening and closing the flow of refrigerant may be installed in the first bypass pipe.

In the fourth bypass pipe and the fifth bypass pipe, a second bypass valve and a third bypass valve for expanding the flowing refrigerant may be installed, respectively.

According to the present invention, the liquid refrigerant accumulated in the accumulator can be vaporized and removed by bypassing the high-temperature refrigerant.

As the accumulated refrigerant is removed, the amount of refrigerant flowing through the entire air conditioning system can be secured, and accordingly, the performance of the air conditioning system can be secured.

In addition, since some of the high-temperature refrigerant generated in the system itself is bypassed, the refrigerant accumulated in the accumulator is used, so there is an advantage that it is not necessary to install a separate device. Accordingly, there is an advantage in that it is possible to reduce the installation cost and installation time for the additional device.

In addition, since the system itself uses a heat source, there is an advantage in that it is possible to maintain proper performance by removing the accumulated refrigerant regardless of the external environment.

In addition, there is an advantage in that the air conditioning system can be effectively operated by removing the refrigerant accumulated in the accumulator as needed.

In addition, there is an advantage in that the bypass pipe is used together with an injection pipe and the like to perform optimal operation according to the state of the refrigerant.

1 is a diagram showing the configuration of an air conditioning system according to a first embodiment of the present invention.
2 is a diagram showing the configuration of an air conditioning system according to a second embodiment of the present invention.
3 is a view showing the flow of refrigerant in the cooling mode in FIG. 2.
4 is a view showing the flow of refrigerant in the heating mode in FIG. 2.
5 is a view showing the operation of the air conditioning system according to an embodiment of the present invention.

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. However, the spirit of the present invention is not limited to the presented embodiments, and those skilled in the art who understand the spirit of the present invention will be able to easily propose other embodiments within the scope of the same idea.

1 is a diagram showing the configuration of an air conditioning system according to a first embodiment of the present invention.

Referring to FIG. 1, an air conditioning system 1 according to a first embodiment of the present invention includes an indoor heat exchanger 20 disposed in an indoor unit and an outdoor heat exchanger 30 disposed in an outdoor unit. The indoor heat exchanger 20 and the outdoor heat exchanger 30 exchange heat with air and function as an evaporator or a condenser.

The indoor unit may be disposed in a predetermined space to provide harmonized air, and the outdoor unit may be disposed outdoors in the predetermined space. In addition, in the indoor unit, an indoor fan 22 and an indoor fan motor 24 forcibly convectively convection air so that the indoor heat exchanger 20 exchanges heat with air in a predetermined space, and the outdoor heat exchanger 20 An outdoor fan 32 and an outdoor fan motor 34 for forced convection of air so that 30 heat exchanges with outdoor air are installed.

The indoor unit and the outdoor unit are connected through a refrigerant pipe to form a refrigerant cycle. In FIG. 1, for convenience, the air conditioning system 1 is not divided into the indoor unit and the outdoor unit, but is illustrated as a refrigerant cycle connected by a refrigerant pipe.

In addition, as shown in FIG. 1, the air conditioning system 1 includes a compressor 45, an accumulator 40, an expansion valve 50, and a flow switching unit 60.

The compressor 45 is configured to compress and discharge gaseous refrigerant in a state of high temperature and high pressure. In this case, although the compressor 45 is shown as one in FIG. 1, a plurality of compressors 45 connected in parallel or in series may be provided.

The accumulator 40 is configured to separate gaseous refrigerant before flowing into the compressor 45. The separated gaseous refrigerant may be introduced into the compressor 45. This will be described in detail later.

The expansion valve 50 is configured to expand the high temperature and high pressure liquid refrigerant condensed in the condenser into the low pressure liquid refrigerant. For example, the expansion valve 50 may include an electric expansion valve (EEV).

1, the expansion valve 50 may be disposed between the indoor heat exchanger 20 and the outdoor heat exchanger 30. In this case, although one expansion valve is illustrated in FIG. 1, a plurality of expansion valves 50 may be provided. For example, the expansion valve 50 may be provided as an expansion valve for expanding the refrigerant heat-exchanged in the indoor heat exchanger 20 and an expansion valve for expanding the refrigerant heat exchanged in the outdoor heat exchanger 30. have.

The flow conversion unit 60 is provided to guide the refrigerant toward the indoor heat exchanger 20 or the outdoor heat exchanger 30. For example, the flow conversion unit 60 may include a four-way valve.

The configuration of the air conditioning system 1 is exemplary, and the above configuration may be omitted or another configuration may be added. For example, an oil separator and various sensors for separating oil from the refrigerant discharged from the compressor 45 may be further included.

The components of the air conditioning system 1 are connected to each other through a refrigerant pipe. Hereinafter, a pipe connecting the compressor 45 and the flow conversion unit 60 is a first pipe 70, and a pipe connecting the flow conversion unit 60 and the indoor heat exchanger 20 is a second pipe. (71), a pipe connecting the indoor heat exchanger 20 and the expansion valve 50 is provided with a third pipe 72, and a pipe connecting the expansion valve 50 and the outdoor heat exchanger 30 is provided. 4 piping 73, a piping connecting the outdoor heat exchanger 30 and the flow conversion unit 60 to a fifth piping 74, a piping connecting the flow conversion unit 60 and the accumulator 40 The sixth pipe 75 and the pipe connecting the accumulator 40 and the compressor 45 are referred to as a seventh pipe 76. At this time, the name of each pipe is arbitrarily written for identification.

The operation of the air conditioning system 1 will be briefly described with reference to FIG. 1.

A case in which the air conditioning system 1 performs a cooling operation, that is, a case in which the predetermined space is cooled, will be described. At this time, the indoor heat exchanger 20 functions as an evaporator, and the outdoor heat exchanger 30 functions as a condenser.

The gaseous refrigerant compressed by the compressor 45 flows to the flow conversion unit 60 along the first pipe 70. The flow conversion unit 60 is provided to connect the first pipe 70 and the fifth pipe 74, and the refrigerant flows to the outdoor heat exchanger 30 along the fifth pipe 74. .

Air forced convection by the outdoor fan 32 and the outdoor fan motor 34 and the refrigerant flowing through the outdoor heat exchanger 30 are heat-exchanged, and the gaseous refrigerant is condensed into a liquid refrigerant. Through the condensation process, the outdoor heat exchanger 30 releases heat to the surroundings.

The condensed liquid refrigerant flows to the expansion valve 50 along the fourth pipe 73, and the expansion valve 50 expands the liquid refrigerant in a high temperature and high pressure state into a liquid refrigerant in a low pressure state. The expanded refrigerant flows to the indoor heat exchanger 20 along the third pipe 72.

Air forced convection by the indoor fan 22 and the indoor fan motor 24 and the refrigerant flowing through the indoor heat exchanger 20 are heat-exchanged, and the liquid refrigerant is evaporated into a gaseous refrigerant. Through the evaporation process, the indoor heat exchanger 20 can achieve a cooling effect by taking away heat from the predetermined space.

The refrigerant discharged from the indoor heat exchanger 20 flows to the flow conversion unit 60 through the second pipe 71. The flow conversion part 60 is provided to connect the second pipe 71 and the sixth pipe 75, and the refrigerant flows to the accumulator 40 along the sixth pipe 75.

In addition, the refrigerant is returned from the accumulator 40 to the compressor 45 along the seventh pipe 76, and the compressed refrigerant is discharged again through the first pipe 70. Through such a circulation process, the predetermined space can be cooled to a target temperature.

A case in which the air conditioning system 1 performs a heating operation, that is, a case in which the predetermined space is heated will be described. At this time, the indoor heat exchanger 20 functions as a condenser, and the outdoor heat exchanger 30 functions as an evaporator.

The gaseous refrigerant compressed by the compressor 45 flows to the flow conversion unit 60 along the first pipe 70. The flow conversion unit 60 is provided to connect the first pipe 70 and the second pipe 71, and the refrigerant flows to the indoor heat exchanger 20 along the second pipe 71. .

Air forced convection by the indoor fan 22 and the indoor fan motor 24 and the refrigerant flowing through the indoor heat exchanger 20 are heat-exchanged, and the gaseous refrigerant is condensed into a liquid refrigerant. Through the condensation process, the indoor heat exchanger 20 can achieve a heating effect by dissipating heat to the predetermined space.

The refrigerant discharged from the indoor heat exchanger 20 flows to the expansion valve 50 along the third pipe 72, and the expansion valve 50 converts a liquid refrigerant in a high temperature and high pressure state into a liquid refrigerant in a low pressure state. Inflate with The expanded refrigerant flows to the outdoor heat exchanger 30 along the fourth pipe 73.

The air forced convection by the outdoor fan 32 and the outdoor fan motor 34 and the refrigerant flowing through the outdoor heat exchanger 30 are heat-exchanged, and the liquid refrigerant is evaporated into a gaseous refrigerant. The evaporated refrigerant flows to the flow conversion unit 60 through the fifth pipe 74, and the flow conversion unit 60 connects the fifth pipe 74 and the sixth pipe 75. It is prepared.

The refrigerant flows to the accumulator 40 along the sixth pipe 75, returns from the accumulator 40 to the compressor 45 along the seventh pipe 76, is compressed, and is then compressed again. It is discharged through the pipe 70. Through such a circulation process, the predetermined space can be heated to a target temperature.

In this case, when at least one of the above-described configurations fails to function properly under a predetermined condition, a refrigerant may accumulate.

For example, when the air conditioning system 1 performs a heating operation, the outdoor temperature is very low, and the outdoor heat exchanger 30 does not properly function as an evaporator, and refrigerant may accumulate.

In detail, a relatively large amount of refrigerant may be discharged from the outdoor heat exchanger 30 in a non-evaporated liquid state. As described above, when the air conditioning system 1 performs a heating operation, the refrigerant discharged from the outdoor heat exchanger 30 is the accumulator along the fifth pipe 74 and the sixth pipe 75. Flows to (40).

The accumulator 40 separates the liquid refrigerant and the gaseous refrigerant, and flows the separated gaseous refrigerant to the compressor 45 along the seventh pipe 76. At this time, the separated liquid refrigerant is accumulated in the accumulator 40.

Accordingly, when a relatively large amount of refrigerant is not evaporated in the outdoor heat exchanger 30, a relatively large amount is accumulated in the accumulator 40.

Alternatively, when the opening degree of the expansion valve 50 is adjusted to adjust the circulation amount and dryness of the refrigerant, the abnormal refrigerant may be discharged from the outdoor heat exchanger or the indoor heat exchanger. When this operation is continued, liquid refrigerant accumulates in the accumulator 40.

In normal operation, since a relatively small amount of liquid refrigerant is introduced into the accumulator 40, only a small amount of refrigerant is present in the accumulator 40. Such a refrigerant may be naturally vaporized during the flow of the refrigerant.

However, as described above, when normal operation is not performed due to external or internal conditions, a relatively large amount of liquid refrigerant flows into the accumulator 40 and is accumulated. At this time, it is difficult to expect natural vaporization because a relatively large amount of liquid refrigerant is present.

Accordingly, refrigerant that does not flow in the accumulator 40 is accumulated, and the total amount of refrigerant flowing through the air conditioning system 1 is reduced. In addition, the low pressure and high pressure of the air conditioning system 1 are reduced as a whole, and the heat exchanger may be condensed. As a result, the capability of the air conditioning system 1 decreases.

In order to prevent the accumulator 40 from accumulating refrigerant, the air conditioning system 1 according to the present invention includes a bypass pipe 100.

The bypass pipe 100 is installed to vaporize the liquid refrigerant accumulated in the accumulator 40. In detail, the bypass pipe 100 is installed so that a high-temperature refrigerant flows inside the accumulator 40.

1, the bypass pipe 100 is provided to connect the first pipe 70 and the seventh pipe 76 through the accumulator 40.

As described above, the refrigerant discharged from the compressor 45 flows through the first pipe 70, and the refrigerant flowing into the compressor 45 flows through the seventh pipe 76. That is, the first pipe 70 may be referred to as a “compressor discharge pipe”, and the seventh pipe 76 may be referred to as a “compressor inlet pipe”.

Accordingly, at least a part of the refrigerant flowing in the first pipe 70 by the bypass pipe 100 flows toward the seventh pipe 76.

That is, the bypass pipe 100 flows the high-temperature refrigerant discharged from the compressor 45 to the accumulator 40.

A bypass valve 110 is installed in the bypass pipe 100 to open and close the flow of refrigerant in the bypass pipe 100. The bypass valve 110 may be opened when there is a refrigerant above a reference value in the accumulator 40. This will be described in detail later.

At this time, the bypass pipe 100, a first bypass pipe 120 extending from the first pipe 70 to the accumulator 40, a second bypass pipe disposed inside the accumulator 40 It is divided into 130 and a third bypass pipe 140 extending from the accumulator 40 to the seventh pipe 76. This is divided for convenience of description, and the bypass pipe 100 may be continuously extended.

The bypass valve 110 may be installed in the first bypass pipe 120. That is, the bypass valve 110 is installed adjacent to the first pipe 70 to open and close the flow of the refrigerant.

The second bypass pipe 130 may be bent and installed in the accumulator 40. In FIG. 1, the second bypass pipe 130 is shown in a once bent shape, but this is exemplary, and the second bypass pipe 130 may be provided in various shapes suitable for heat exchange.

In addition, the second bypass pipe 130 may be disposed on a lower side of the accumulator 40 in which a liquid refrigerant is accumulated. Accordingly, the liquid refrigerant accumulated in the accumulator 40 may be vaporized through heat exchange with the second bypass pipe 130.

In detail, the liquid refrigerant accumulated in the accumulator 40 is vaporized by receiving heat from the high-temperature gas phase refrigerant flowing through the second bypass pipe 130. On the other hand, the gaseous refrigerant flowing through the second bypass pipe 130 may be condensed by taking away heat.

A bypass expansion valve 150 may be installed in the third bypass pipe 140. The bypass expansion valve 150 may expand and vaporize the liquid refrigerant generated in the heat exchange process described above.

1, the refrigerant vaporized in the bypass expansion valve 150 may flow to the compressor 45 through the seventh pipe 76. In addition, the bypass pipe is directly connected to the compressor 45 so that the refrigerant vaporized in the bypass expansion valve 150 may flow directly to the compressor 45.

In this way, the refrigerant accumulated in the accumulator 40 may be vaporized using the high-temperature refrigerant inside the system. In addition, by using the bypass pipe 100 as necessary, the air conditioning system 1 can be effectively operated.

2 is a diagram showing the configuration of an air conditioning system according to a second embodiment of the present invention. The air conditioning system according to the first embodiment described above is indicated by reference numeral 1, and the air conditioning system according to the second embodiment described below is indicated by reference numeral 10. In addition, for the same components as those described above, the above description is referred to and the same reference numerals are used.

2, the air conditioning system 10 according to the second embodiment of the present invention includes an indoor heat exchanger 20, an outdoor heat exchanger 30, an accumulator 40, a compressor 45, and expansion. A valve 50 is included. In addition, first to seventh pipes (70, 71, 72, 73, 74, 75, 76) connecting the components and a flow conversion unit 60 are included.

In addition, the air conditioning system 10 according to the idea of the present invention includes a bypass pipe 100 passing through the accumulator 40. The bypass pipe 100 may be divided into first to third bypass pipes 120, 130, and 140 connecting the first pipe 70 and the bypass branch unit 180.

In detail, the first bypass pipe 120 connects the first pipe 70 and the accumulator 40, and a first bypass valve 110 is installed. In this case, the first bypass valve 110 may be provided in the form of a valve that opens and closes the flow of the refrigerant.

In addition, the second bypass pipe 130 is installed inside the accumulator 40, and the third bypass pipe 140 connects the accumulator 40 and the bypass branch unit 180. .

In addition, the bypass pipe 100 includes a fourth bypass pipe 160 and a fifth bypass pipe 170 respectively extending from the bypass branch unit 180. A second bypass valve 165 and a third bypass valve 175 are respectively installed in the fourth bypass pipe 160 and the fifth bypass pipe 170.

The fourth bypass pipe 160 extends from the bypass branch portion 180 to the seventh pipe 76. In addition, the fourth bypass pipe 160 may be directly connected to the compressor 45. The fifth bypass pipe 170 extends from the bypass branch unit 180 to a second injection pipe 85 to be described later.

In addition, the air conditioning system 10 according to the second embodiment of the present invention includes an injection pipe 80. As shown in FIG. 2, one end of the injection pipe 80 may be disposed in a third pipe 72 connecting the indoor heat exchanger 20 and the expansion valve 50.

In addition, one end of the injection pipe 80 may be disposed in a fourth pipe 73 connecting the outdoor heat exchanger 30 and the expansion valve 50. That is, one end of the injection pipe 80 may be disposed between the indoor heat exchanger 20 or the outdoor heat exchanger 30 and the expansion valve 50.

In addition, the other end of the injection pipe 80 is connected to the compressor 45 or the accumulator 40. That is, the injection pipe 80 injects the refrigerant that has passed through the indoor heat exchanger 20 or the outdoor heat exchanger 30 toward the compressor 45.

An injection branch portion 84 may be provided in the injection pipe 80, and an injection heat exchanger 90 and at least one injection valve 83, 86, 88 may be installed.

In detail, in the injection pipe 80, a first injection pipe 82 connecting the third pipe 72 and the injection branch part 84, and a second injection pipe 82 extending from the injection branch part 84, respectively. An injection pipe 85 and a third injection pipe 87 are included.

The first injection pipe 82 is disposed to pass through the injection heat exchanger 90. In this case, the injection heat exchanger 90 is provided to exchange heat between the first injection pipe 82 and the third pipe 82.

In addition, a first injection valve 83 is installed in the first injection pipe 82. For example, the first injection valve 83 may be provided in the form of a valve that expands a flowing refrigerant.

The second injection pipe 85 extends from the injection branch part 84 to the compressor 45. In this case, the second injection pipe 85 may be referred to as a “compressor inlet pipe” as the refrigerant is supplied to the compressor 45.

In addition, a second injection valve 86 is installed in the second injection pipe 85. For example, the second injection valve 86 may be provided in the form of a valve that expands a flowing refrigerant.

The third injection pipe 87 extends from the injection branch portion 84 to the accumulator 40. In addition, a third injection valve 88 is installed in the third injection pipe 87. For example, the third injection valve 88 may be provided in the form of a valve that opens and closes the flow of the refrigerant.

Hereinafter, the flow of the refrigerant according to the driving of the air conditioning system 10 will be described in detail with reference to the configuration described above.

3 is a view showing the flow of refrigerant in the cooling mode in FIG. 2. 3 illustrates an exemplary flow of refrigerant when the air conditioning system 10 performs a cooling operation.

First, looking at the overall flow of the refrigerant, it flows sequentially to the compressor 45, the outdoor heat exchanger 30, the expansion valve 50, and the indoor heat exchanger 20, and passes through the accumulator 40 again. It flows to the compressor 45 and circulates.

Refrigerant may accumulate in the accumulator 40 due to external or internal conditions in the circulation process. In this case, the first bypass valve 110 is opened so that the refrigerant flows through the bypass pipe 100.

The refrigerant flows from the first pipe 70 to the bypass pipe 100 according to the pressure difference. That is, at least a portion of the refrigerant discharged from the compressor 45 and flowing into the first pipe 70 may flow into the bypass pipe 100.

In detail, the refrigerant flowing through the first bypass pipe 120 and into the second bypass pipe 130 is heat-exchanged with the refrigerant inside the accumulator 40. In this case, the liquid refrigerant inside the accumulator 40 may be vaporized by receiving heat from the high-temperature refrigerant flowing through the second bypass pipe 130.

The liquid refrigerant existing in the accumulator 40 may be vaporized and flow to the compressor 45 along the seventh pipe 76. Accordingly, as at least a part of the refrigerant accumulated in the accumulator 40 flows, the total amount of refrigerant increases and the performance of the air conditioning system 10 can be secured.

On the other hand, the refrigerant flowing through the second bypass pipe 130 may be condensed at least partially by taking away heat to flow along the third bypass pipe 140.

The refrigerant from the bypass branch unit 180 flows to the fourth bypass pipe 160 and is expanded by the second bypass valve 165. In this case, the third bypass valve 175 may block the flow of the refrigerant to the fifth bypass pipe 170.

Accordingly, the refrigerant flowing through the fourth bypass pipe 160 may be vaporized and flow through the seventh pipe 76. The refrigerant flowing through the seventh pipe 76 may flow into the compressor 45.

4 is a view showing the flow of refrigerant in the heating mode in FIG. 2. 4 illustrates an exemplary flow of refrigerant when the air conditioning system 10 is in a heating operation.

First, looking at the overall flow of the refrigerant, it flows sequentially to the compressor 45, the indoor heat exchanger 20, the expansion valve 50, and the outdoor heat exchanger 30, and passes through the accumulator 40 again. It flows to the compressor 45 and circulates.

Refrigerant may accumulate in the accumulator 40 due to external or internal conditions in the circulation process. In particular, since the outdoor heat exchanger 30 functions as an evaporator and is affected by the outdoor temperature, refrigerant is more likely to be accumulated than when the air conditioning system 10 shown in FIG. 3 performs a cooling operation. I can.

When the refrigerant is accumulated in the accumulator 40 as described above, the first bypass valve 110 is opened and the refrigerant flows to the bypass pipe 100. That is, at least a portion of the refrigerant discharged from the compressor 45 and flowing into the first pipe 70 may flow into the bypass pipe 100.

In detail, the refrigerant flowing through the first bypass pipe 120 and into the second bypass pipe 130 is heat-exchanged with the refrigerant inside the accumulator 40. The liquid refrigerant present in the accumulator 40 may be vaporized and flow to the compressor 45.

On the other hand, the refrigerant flowing through the second bypass pipe 130 may be condensed at least partially by taking away heat to flow along the third bypass pipe 140.

In this case, the refrigerant flows from the bypass branch unit 180 to the fourth bypass pipe 160 and may be expanded by the second bypass valve 165. In this case, the third bypass valve 175 may block the flow of the refrigerant to the fifth bypass pipe 170. Accordingly, the refrigerant flowing through the fourth bypass pipe 160 may flow through the seventh pipe 76 and flow into the compressor 45.

In addition, as shown in FIG. 4, the refrigerant flows from the bypass branch unit 180 to the fifth bypass pipe 170 and may be expanded by the third bypass valve 175. In this case, the second bypass valve 165 may block the flow of the refrigerant to the fourth bypass pipe 160.

The fifth bypass pipe 170 is connected to the second injection pipe 85. Accordingly, the refrigerant may be expanded in the second injection valve 86 in the second injection pipe 85 and introduced into the compressor 45.

Referring to FIG. 4, at least a portion of the refrigerant flowing through the third pipe 72 flows through the first injection pipe 82 and is expanded by the first injection valve 83. The expanded refrigerant is heat-exchanged with the refrigerant flowing through the third pipe 72 in the injection heat exchanger 90 and flows to the injection branch part 84.

In FIG. 4, flow from the injection branch portion 84 to the second injection pipe 85 is shown, but may flow to the third injection pipe 87 if necessary. The second injection valve 86 and the third injection valve 88 may open and close the second injection pipe 85 and the third injection pipe 87 respectively to control the flow of the refrigerant.

In addition, the flow of the refrigerant in the injection pipe 80 and the bypass pipe 100 may be controlled independently of each other.

The flow of the refrigerant in the injection pipe 80 and the bypass pipe 100 may be formed differently as necessary. That is, the flow of the refrigerant to the injection pipe 80 and the bypass pipe 100 may be selected according to an external condition or an internal condition. Accordingly, it is possible to operate the air conditioning system 10 more effectively.

5 is a view showing the operation of the air conditioning system according to an embodiment of the present invention.

As shown in FIG. 5, when the air conditioning system 10 is driven (S10), the compressor 45 is operated to allow the refrigerant to flow. Depending on whether the air conditioning system 10 is driven in a cooling mode or a heating mode, the flow conversion unit 60 switches the flow of the refrigerant.

After a predetermined period of time after the air conditioning system 10 is driven, the accumulator 40 detects whether the refrigerant has accumulated (S20). The predetermined time may be set differently as necessary.

Various methods of detecting whether the accumulator 40 has accumulated refrigerant may be provided. For example, a water level sensor may be installed in the accumulator 40 to measure the level of the accumulated liquid refrigerant. In addition, it is possible to detect whether the refrigerant is accumulated through values such as the efficiency of the air conditioning system 10 and the pressure of the flowing refrigerant.

The refrigerant accumulation amount sensed in this way is compared with a reference value (S30). The reference value can be understood as a refrigerant accumulation amount that has relatively little influence on driving the air conditioning system 10.

When the sensed refrigerant accumulation amount is less than the reference value, it may be determined that the refrigerant has not been relatively accumulated. Therefore, it is possible to continuously monitor whether or not the refrigerant is accumulated.

On the other hand, when the sensed refrigerant accumulation amount is greater than the reference value, it may be determined that the refrigerant has accumulated. Accordingly, the bypass valve 110 is opened (S40), and the refrigerant flows to the bypass pipe 100 (S50).

As the refrigerant flows through the bypass pipe 100, the liquid refrigerant accumulated in the accumulator 40 may be vaporized. Accordingly, the accumulated refrigerant is reduced, and the air conditioning system 10 can secure proper performance.

1, 10: air conditioning system 20: indoor heat exchanger
30: outdoor heat exchanger 40: accumulator
45: compressor 50: expansion valve
60: flow switching unit 80: injection valve
100: bypass valve

Claims (10)

A compressor for compressing the refrigerant at high temperature and high pressure;
A compressor discharge pipe through which the refrigerant discharged from the compressor flows;
An accumulator for separating a refrigerant into a gas phase refrigerant and a liquid refrigerant and supplying the gas phase refrigerant to the compressor;
An outdoor heat exchanger for exchanging refrigerant with outdoor air;
An indoor heat exchanger for exchanging refrigerant with indoor air;
An expansion valve installed between the indoor heat exchanger and the outdoor heat exchanger;
A compressor inlet pipe through which refrigerant flowing into the compressor flows by connecting the compressor and the accumulator;
A bypass pipe connecting the compressor discharge pipe and the compressor inlet pipe and passing through the accumulator; And
Including; an injection pipe for injecting the outdoor heat exchanger or the refrigerant passing through the outdoor heat exchanger toward the compressor,
The bypass pipe may include: a first bypass pipe extending from the compressor discharge pipe to the accumulator;
A second bypass pipe disposed inside the accumulator;
A third bypass pipe extending from the accumulator to a bypass branch;
A fourth bypass pipe extending from the bypass branch to the compressor inlet pipe; And
A fifth bypass pipe extending from the bypass branch portion to the injection pipe; and,
And a second bypass valve and a third bypass valve for expanding the refrigerant flowing through the fourth bypass pipe and the fifth bypass pipe, respectively. delete The method of claim 1,
An air conditioning system, wherein a bypass valve for opening and closing the flow of refrigerant is installed in the first bypass pipe. The method of claim 1,
And the second bypass pipe is bent and installed in the accumulator. The method of claim 1,
Air, characterized in that the second bypass pipe is disposed on the lower side of the accumulator in which the liquid refrigerant is accumulated so that the liquid refrigerant accumulated in the accumulator can be vaporized through heat exchange with the second bypass pipe. Harmony system. The method of claim 1,
An air conditioning system, characterized in that a bypass expansion valve for expanding the flowing refrigerant is installed in the third bypass pipe. delete delete delete delete

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