KR101873419B1 - Refrigeration cycle apparatus for air conditioner - Google Patents

Abstract

The present invention relates to a refrigerating cycle apparatus for an air conditioner, which includes: a compressor; a flow-switching valve provided at a discharge side of the compressor; an outdoor heat exchanger linked to the flow-switching valve; an indoor heat exchanger linked to the flow-switching valve; an intermediate heat exchanger having a first heat exchanger and a second heat exchanger and interposed between the outdoor heat exchanger and the indoor heat exchanger; a first expansion device and a second expansion device provided at both sides of the first heat exchanger; a first link fluid passage to link a point between the first heat exchanger and the first expansion device with the second heat exchanger; a second link fluid passage to link the second heat exchanger to a suction side of the compressor; and a third expansion device provided in the first link fluid passage. Accordingly, the supply of a coolant is limited in the defrosting operation, thereby preventing an interior temperature from being lowered due to the coolant.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a refrigeration cycle apparatus for an air conditioner,

The present invention relates to a refrigeration cycle apparatus for an air conditioner.

As is well known, the air conditioner includes an indoor unit provided in an indoor unit and an indoor unit provided in an outdoor unit.

The indoor unit includes an indoor heat exchanger to cool or heat indoor air.

The indoor unit and the outdoor unit each include a refrigerating cycle device in which refrigerant circulates and exchanges heat with indoor air.

The refrigeration cycle apparatus is implemented as a so-called vapor compression refrigeration cycle apparatus having a compressor for compressing refrigerant, a condenser for releasing refrigerant, an expansion device for expanding the refrigerant under reduced pressure, and an evaporator for evaporating the refrigerant by absorbing latent heat.

And a flow path switching valve for switching the flow path of the refrigerant is provided on the discharge side of the compressor.

Thereby, the air conditioner performs the cooling operation in which the compressed refrigerant is circulated through the outdoor heat exchanger, the expansion device, and the indoor heat exchanger, and the refrigerant is circulated through the indoor heat exchanger, the expansion device, and the outdoor heat exchanger So that the indoor air can be heated.

On the other hand, during the heating operation, the outdoor heat exchanger is frosted with water in the air.

When the congestion amount increases in the outdoor heat exchanger, the heat exchange between the air and the refrigerant of the outdoor heat exchanger is reduced, and the heating operation efficiency is lowered.

And a defrosting operation is performed in which the high temperature refrigerant discharged from the compressor is supplied to the outdoor heat exchanger to remove the property of the outdoor heat exchanger when the amount of the impregnation increases in the outdoor heat exchanger.

However, in the conventional refrigeration cycle apparatus for an air conditioner, the refrigerant discharged from the compressor and passed through the outdoor heat exchanger is decompressed and expanded in the expansion device, and then circulated via the indoor heat exchanger. There is a problem that cold air is generated.

Further, the subcooled refrigerant passing through the indoor unit can not sufficiently evaporate and is present inside the accumulator, so that it takes a relatively long time to reach a normal operation at the time of resuming heating operation.

In addition, in the defrosting operation, although the indoor heat exchanging is not performed in the room, the indoor unit is passed through, and the circulation path of the refrigerant becomes longer, thereby shortening the defrosting operation time.

It is therefore an object of the present invention to provide a refrigeration cycle apparatus for an air conditioner capable of suppressing a decrease in room temperature due to a refrigerant flow of an indoor unit during a defrosting operation.

Another object of the present invention is to provide a refrigeration cycle apparatus for an air conditioner capable of shortening a normal operation reaching time at the time of heating restart after defrosting operation.

It is still another object of the present invention to provide a refrigeration cycle apparatus for an air conditioner capable of shortening a circulation path of a refrigerant during a defrosting operation.

In order to achieve the above object, the present invention provides a compressor comprising: a compressor; A flow path switching valve provided on a discharge side of the compressor; An outdoor heat exchanger connected to the flow path switching valve; An indoor heat exchanger connected to the flow path switching valve; An intermediate heat exchanger having a first heat exchanger and a second heat exchanger, the intermediate heat exchanger being disposed between the outdoor heat exchanger and the indoor heat exchanger; A first expansion device and a second expansion device provided on both sides of the first heat exchanger; A first connection passage connecting a point between the first heat exchanger and the first expansion device and the second heat exchanger; A second connection passage connecting the second heat exchange unit and the suction side of the compressor; And a third expansion device provided in the first connection passage. The present invention also provides a refrigeration cycle apparatus for an air conditioner.

In an embodiment, an accumulator provided on a suction side of the compressor; And a third connection passage branched from the first connection passage and connected to the suction side of the accumulator.

In an embodiment, the apparatus further comprises a third connection path opening / closing valve for opening / closing the third connection path.

The apparatus may further include an injection channel branched from the second connection passage and flowing into the intermediate pressure portion of the compressor.

In an embodiment, the apparatus further comprises a three-way valve for selectively opening and closing the second connection passage and the injection passage.

And a controller for controlling the first expansion device, the second expansion device and the third expansion device, respectively, in the defrosting operation of the outdoor heat exchanger.

The control unit controls the first expansion device, the second expansion device, and the third expansion device so that the refrigerant passed through the outdoor heat exchanger is sucked into the compressor via the intermediate heat exchanger during the defrosting operation of the outdoor heat exchanger Lt; / RTI >

In an exemplary embodiment, the system further includes a frost detection unit that senses frosting of the outdoor heat exchanger.

The control unit may control the refrigerant of the outdoor heat exchanger to be sucked into the compressor via the intermediate heat exchanger when the degree of impregnation of the outdoor heat exchanger is equal to or lower than the first set level based on the detection result of the frost detection unit.

Wherein the control unit controls the first expansion device and the second expansion device so that the refrigerant passed through the outdoor heat exchanger is sucked into the compressor via the indoor heat exchanger and the intermediate heat exchanger respectively when the degree of impregnation exceeds the first setting level, 2 < / RTI > expansion device and the third expansion device, respectively.

According to another aspect of the present invention, there is provided a compressor comprising: a compressor; A flow path switching valve provided on a discharge side of the compressor; An outdoor heat exchanger connected to the flow path switching valve; An indoor heat exchanger connected to the flow path switching valve; An intermediate heat exchanger having a first heat exchanger and a second heat exchanger, the intermediate heat exchanger being disposed between the outdoor heat exchanger and the indoor heat exchanger; A first expansion device and a second expansion device provided on both sides of the first heat exchanger; A first connection passage connecting a point between the first heat exchanger and the first expansion device and the second heat exchanger; A third expansion device provided in the first connection passage; A second connection passage connecting the second heat exchange unit and the suction side of the compressor; A third connection passage branched from the first connection passage; An accumulator provided in the third connection passage; An accumulator heat exchanger provided inside the accumulator; A fourth connection passage branched from the third connection passage and connected to the accumulator heat exchanger; And a fourth expansion device provided in the fourth connection passage. The present invention also provides a refrigeration cycle apparatus for an air conditioner.

The apparatus may further include a third connection passage opening / closing valve provided in the third connection passage for opening / closing the third connection passage.

The apparatus may further include an injection flow path branched from the second connection flow path and flowing into an intermediate pressure portion of the compressor.

The present invention may further comprise a three-way valve provided in the branching region of the second connection passage and the injection passage for selectively opening and closing the second connection passage and the injection passage.

The control system may further include a controller for controlling the first expansion device, the second expansion device, the third expansion device, and the fourth expansion device, respectively, in the defrosting operation of the outdoor heat exchanger.

In the embodiment, the controller may control the first expansion device, the second expansion device, the third expansion device, the second expansion device, and the third expansion device so that the refrigerant passed through the outdoor heat exchanger is sucked into the compressor via the intermediate heat exchanger during the defrosting operation of the outdoor heat exchanger. Device and the fourth expansion device, respectively.

In an exemplary embodiment, the system may further include a frost detection unit that detects frosting of the outdoor heat exchanger. ,

In an embodiment, when the degree of impregnation of the outdoor heat exchanger is equal to or lower than a first set level based on the detection result of the conception detecting unit, the control unit causes the refrigerant of the outdoor heat exchanger to be sucked into the compressor via the intermediate heat exchanger The first expansion device, the second expansion device, the third expansion device, and the fourth expansion device, respectively.

In an embodiment, when the conception level of the outdoor heat exchanger exceeds the first set level and is equal to or lower than the second set level as a result of detection by the conception sensing unit, the control unit controls the refrigerant passing through the outdoor heat exchanger, The second expansion device, the third expansion device, and the fourth expansion device, respectively, to be sucked into the compressor via the accumulator heat exchanger and the accumulator heat exchanger, respectively.

In an embodiment, when the conception level of the outdoor heat exchanger exceeds the second set level as a result of the detection by the conception detecting unit, the control unit controls the refrigerant passing through the outdoor heat exchanger such that the refrigerant passing through the intermediate heat exchanger, The first expansion device, the second expansion device, the third expansion device, and the fourth expansion device, respectively, so as to be sucked into the compressor via the compressor and the indoor heat exchanger, respectively.

As described above, according to the embodiment of the present invention, the refrigerant passing through the outdoor heat exchanger during the defrosting operation is sucked into the compressor via the intermediate heat exchanger to suppress the inflow of the indoor heat exchanger, can do.

Further, since the refrigerant passed through the outdoor heat exchanger is heat-exchanged in the intermediate heat exchanger, it is possible to shorten the normal operation reaching time in the heating restart after the defrost operation.

Further, the intermediate heat exchanger is disposed between the outdoor heat exchanger and the indoor heat exchanger, and the refrigerant passed through the outdoor heat exchanger during the defrosting operation is sucked into the compressor via the intermediate heat exchanger, thereby shortening the circulation path of the refrigerant.

In addition, the accumulator heat exchanger is disposed in the accumulator, and the refrigerant passed through the outdoor heat exchanger is sucked into the compressor via the intermediate heat exchanger and the accumulator heat exchanger during the defrosting operation, The circulation path of the refrigerant can be shortened and the circulation flow rate of the refrigerant can be increased, so that the defrosting time of the outdoor heat exchanger can be shortened.

In addition, the accumulator heat exchanger is disposed in the accumulator, and the refrigerant passed through the outdoor heat exchanger is sucked into the compressor via the intermediate heat exchanger, the accumulator heat exchanger and the indoor heat exchanger during the defrosting operation, thereby increasing the circulating flow rate of the refrigerant The defrosting time of the outdoor heat exchanger can be shortened.

1 is a configuration diagram of a refrigeration cycle apparatus of an air conditioner according to an embodiment of the present invention;
FIG. 2 is a view for explaining a flow of a refrigerant during the defrosting operation of FIG. 1;
FIG. 3 is a view for explaining another flow of the refrigerant in the defrosting operation of FIG. 1,
Fig. 4 is a control block diagram of Fig. 1,
5 is a configuration diagram of a refrigeration cycle apparatus of an air conditioner according to another embodiment of the present invention.
FIG. 6 is a view for explaining the flow of the refrigerant during the defrosting operation of FIG. 5;
7 is a view for explaining another flow of the refrigerant in the defrosting operation of FIG. 5,
8 is a view for explaining another flow of the refrigerant in the defrosting operation of FIG. 5,
Fig. 9 is a control block diagram of Fig. 5; Fig.

Hereinafter, embodiments disclosed in this specification will be described in detail with reference to the accompanying drawings. In this specification, the same or similar reference numerals are given to the same or similar components in different embodiments, and the description thereof is replaced with the first explanation. As used herein, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. In the following description of the embodiments of the present invention, a detailed description of related arts will be omitted when it is determined that the gist of the embodiments disclosed herein may be blurred. In addition, it should be noted that the attached drawings are only for easy understanding of the embodiments disclosed in the present specification, and should not be construed as limiting the technical idea disclosed in the present specification by the attached drawings.

As shown in FIG. 1, the refrigeration cycle apparatus of an air conditioner according to an embodiment of the present invention includes a compressor 110; A flow path switching valve 120 provided on the discharge side of the compressor 110; An outdoor heat exchanger (130) connected to the flow path switching valve (120); An indoor heat exchanger 310 connected to the flow path switching valve 120; An intermediate heat exchanger (140) having a first heat exchanging part (142) and a second heat exchanging part (144) and provided between the outdoor heat exchanger (130) and the indoor heat exchanger (310); A first expansion device (150) and a second expansion device (160) provided on both sides of the first heat exchanging part (142); A first connection passage 170 connecting a point between the first heat exchanging part 142 and the first expansion device 150 and the second heat exchanging part 144; A second connection passage 180 connecting the second heat exchange unit 144 and the suction side of the compressor 110; And a third expansion device (190) provided in the first connection passage (170).

A flow path switching valve 120 may be provided on the discharge side of the compressor 110 to switch the flow path of the refrigerant.

An accumulator 240 may be provided on the suction side of the compressor 110, for example.

The accumulator 240 may be connected to the indoor heat exchanger 310 and the compressor 110, for example.

The flow path switching valve 120 may be implemented, for example, as a four-way valve.

An outdoor heat exchanger (130) may be connected to one side of the flow path switching valve (120).

An outdoor fan 135 for blowing air to the outdoor heat exchanger 130 may be provided on one side of the outdoor heat exchanger 130.

An indoor heat exchanger (310) may be connected to the other side of the flow path switching valve (120).

An indoor fan (315) for blowing air to the indoor heat exchanger (310) may be provided at one side of the indoor heat exchanger (310).

The outdoor heat exchanger (130) and the indoor heat exchanger (310) may be formed with a refrigerant passage so that the refrigerant can flow.

Meanwhile, the intermediate heat exchanger 140 may be provided in the refrigerant flow path connecting the outdoor heat exchanger 130 and the indoor heat exchanger 310.

The air conditioner of the present embodiment includes an indoor unit 300 disposed in the room including the indoor heat exchanger 310 and the indoor fan 315 and the indoor unit 300 disposed in the indoor unit 300 and the outdoor heat exchanger 130, And an outdoor unit (100) having an intermediate heat exchanger (140) and disposed outdoors.

The outdoor unit 100 may include the flow path switching valve 120 and the accumulator 240.

The outdoor unit 100 may be provided with opening and closing valves 102 and 103 for opening and closing refrigerant flow paths respectively connected to the indoor units 300, for example.

The intermediate heat exchanger 140 may include a first heat exchanger 142 and a second heat exchanger 144, for example, in which refrigerant flows while being heat-exchanged.

The first heat exchanging unit 142 and the second heat exchanging unit 144 may be configured to include a plurality of zigzag heat transfer tubes, for example, to increase the heat exchange area.

One end of the first heat exchanging unit 142 may be connected to the outdoor heat exchanger 130, for example.

The other end of the first heat exchanging unit 142 may be connected to the indoor heat exchanger 310, for example.

A first expansion device (150) and a second expansion device (160) may be provided on both sides of the first heat exchanging part (142).

The first expansion device (150) may be installed at an end of the first heat exchanging part (142) on the side of the indoor heat exchanger (310).

The second expansion device (160) may be installed at an end of the first heat exchanging part (142) on the side of the outdoor heat exchanger (130).

The first expansion device and the second expansion device 160 may each be embodied as an electronic expansion valve.

Thereby, the opening degree of each of the first expansion device 150 and the second expansion device 160 can be adjusted by the electrical signal.

The first heat exchanging unit 142 and the second heat exchanging unit 144 may be connected to each other by, for example, a first connecting flow path 170.

The first connection passage 170 is branched, for example, between the first heat exchanger 142 and the first expansion device 150, and the other end is connected to the second heat exchanger 144, As shown in FIG.

The first connection passage 170 may be provided with a third expansion device 190, for example.

The third expansion device 190 may be implemented by, for example, an electronic expansion valve.

Thus, the opening degree of the third expansion device 190 can be adjusted by an electrical signal.

The second connection passage 180 may be connected to the other end of the second heat exchanger 144, for example, connected to the suction side of the compressor 110.

An injection flow path 210 connected to an intermediate pressure portion of the compressor 110 may be connected to the second connection flow path 180.

Thus, the refrigerant passed through the intermediate heat exchanger 140 can be introduced into the intermediate pressure portion of the compressor 110.

The second connection passage 180 may be provided with a three-way valve 215 for selectively controlling the flow path of the second connection passage 180 and the injection passage 210.

The three-way valve 215 is controlled by the control unit to be described later so that the injection flow path 210 can be opened according to a predetermined condition during the cooling operation or the heating operation so that the cooling operation efficiency and the heating operation efficiency are respectively Can be improved.

The first connection passage 170 may be connected to the first connection passage 170 at one end and the third connection passage 230 may be connected to the accumulator 240 at the other end.

One end of the third connection passage 230 may be connected to the upstream side of the third expansion device 190 and the other end may be connected to the inflow side of the accumulator 240 .

The outlet side of the accumulator 240 may be joined to the suction side of the compressor 110 by being joined with the second connection passage 180.

Meanwhile, as shown in FIG. 4, the refrigeration cycle apparatus of the air conditioner of the present embodiment may include a control unit 280 including a control program and implemented by a microprocessor.

The controller 280 controls the refrigerant passing through the outdoor heat exchanger 130 to flow into the compressor 110 via the intermediate heat exchanger 140, for example, during the defrosting operation of the outdoor heat exchanger 130. [ The second expansion device 160, and the third expansion device 190 so as to be sucked into the first expansion device 150, the second expansion device 160, and the third expansion device 190, respectively.

For example, the conception detecting unit 285 that senses the conception of the outdoor heat exchanger 130 may be communicatively connected to the control unit 280.

The frost detection unit 285 may be configured to detect the temperature of the piping of the outdoor heat exchanger 130 and determine the degree of conception.

The frost detection unit 285 detects the outdoor temperature at which the outdoor heat exchanger 130 is installed, the piping temperature of the outdoor heat exchanger 130 and / or the temperature of the refrigerant at the freezing point of the outdoor heat exchanger 130 And may be configured to determine the implantation degree in consideration of the cumulative operation time and the like.

The control unit 280 may control the outdoor heat exchanger 130 such that the outdoor heat exchanger 130 is operated in the defrosting operation mode, The first expansion device 150, the second expansion device 160, and the second expansion device 160 may be arranged such that the refrigerant passed through the outdoor heat exchanger 130 is sucked into the compressor 110 via the intermediate heat exchanger 140, 3 expansion device 190, respectively.

The controller 280 controls the outdoor heat exchanger 130 to cool the outdoor heat exchanger 130 when the degree of conception of the outdoor heat exchanger 130 sensed by the conception sensing unit 285 exceeds the first set value, The first expansion device 150 and the second expansion device 160 may be connected to the intermediate heat exchanger 140 and the indoor heat exchanger 310 such that the refrigerant can flow into the compressor 110 via the intermediate heat exchanger 140 and the indoor heat exchanger 310, And the third expansion device 190, respectively.

The control unit 280 can control the flow switching valve 120 so that the refrigerant discharged from the compressor 110 flows into the outdoor heat exchanger 130 during the cooling operation .

The refrigerant introduced into the outdoor heat exchanger 130 is discharged and can be decompressed and expanded in the first expansion device 150 via the second expansion device 160 and the intermediate heat exchanger 140.

The refrigerant that has passed through the first expansion device 150 is evaporated by absorbing latent heat in the indoor heat exchanger 310 and can be sucked into the compressor 110 via the accumulator 240.

The control unit 280 controls the third expansion device 190 and the third connection path opening / closing valve 235 so that the first connection path 170 and the second connection path 180 may be blocked, respectively, Respectively.

1, the control unit 280 controls the flow switching valve 120 so that the refrigerant discharged from the compressor 110 flows into the indoor heat exchanger 310, Can be controlled.

The refrigerant introduced into the indoor heat exchanger 310 may be heat-exchanged with the indoor air to raise the indoor air temperature.

The refrigerant passed through the indoor heat exchanger 310 may be expanded under pressure in the second expansion device 160 via the first expansion device 150 and the intermediate heat exchanger 140.

The refrigerant having passed through the second expansion device (160) can be evaporated by absorbing latent heat in the outdoor heat exchanger (130).

On the other hand, in the heating operation, when the degree of conception of the outdoor heat exchanger 130 sensed by the conception sensing unit 285 is equal to or lower than the first set value, the control unit 280, for example, Similarly, the first expansion device 150, the second expansion device 160, and the second expansion device 160 may be arranged such that the refrigerant passing through the outdoor heat exchanger 130 is sucked into the compressor 110 via the intermediate heat exchanger 140, 3 expansion device 190 can be controlled.

Accordingly, during the defrosting operation of the outdoor heat exchanger 130, the refrigerant passed through the outdoor heat exchanger 130 can be sucked into the compressor 110 via the intermediate heat exchanger 140.

In this case, since the refrigerant passing through the outdoor heat exchanger 130 does not pass through the indoor heat exchanger 310, the circulation path of the refrigerant can be shortened.

Accordingly, the defrost operation time of the outdoor heat exchanger 130 can be shortened.

In addition, since the refrigerant does not flow through the indoor heat exchanger 310 during the defrosting operation, cold air is not generated in the room, so that the room temperature is not lowered by the refrigerant.

In addition, since the refrigerant does not flow into the indoor heat exchanger (310) during the defrosting operation, the flow noise of the refrigerant does not occur in the indoor unit.

More specifically, for example, the controller 280 controls the outdoor heat exchanger 130 such that the refrigerant discharged from the compressor 110 flows into the outdoor heat exchanger 130 when the degree of conception of the outdoor heat exchanger 130 is equal to or lower than the first set value. The flow path switching valve 120 can be controlled to flow into the flow path switching valve 120.

The refrigerant discharged from the compressor (110) flows into the outdoor heat exchanger (130) and is discharged, so that the performance of the outdoor heat exchanger (130) can be removed.

The control unit 280 may control the second expansion device 160 such that the opening degree of the second expansion device 160 is opened to the full extent (for example, 100%).

The control unit 280 may control the first expansion device 150 to shut off the flow path of the first expansion device 150.

The control unit 280 may control the third expansion device 190 so that the refrigerant in the intermediate heat exchanger 140 may be decompressed and expanded.

The control unit 280 controls the three-way valve 215 so that the refrigerant passing through the intermediate heat exchanger 140 is sucked into the suction side of the compressor 110 and the inflow of the intermediate pressure portion of the compressor 110 is blocked can do.

The control unit 280 may control the third connection passage opening / closing valve 235 so that the third connection passage 230 is blocked.

The control unit 280 may control the third connection passage opening / closing valve 235 via a portion of the refrigerant passing through the intermediate heat exchanger 140 via the accumulator 240.

A part of the refrigerant passing through the outdoor heat exchanger 130 is evaporated by absorbing the latent heat in the intermediate heat exchanger 140 and the remaining part of the refrigerant is discharged through the third connection passage 230 and the accumulator 240 The refrigerant passing through the intermediate heat exchanger 140 may be combined with the refrigerant and sucked into the compressor 110.

3, the control unit 280 determines whether the degree of impregnation of the outdoor heat exchanger 130 sensed by the conception sensing unit 285 exceeds the first set value The refrigerant passing through the outdoor heat exchanger 130 is sucked into the compressor 110 via the intermediate heat exchanger 140 and the indoor heat exchanger 310. The first expansion device 150, The second expansion device 160 and the third expansion device 190 can be controlled.

More specifically, the control unit 280 may control the flow switching valve 120 so that the refrigerant discharged from the compressor 110 flows into the outdoor heat exchanger 130 during the defrosting operation.

The refrigerant flowing into the outdoor heat exchanger 130 is radiated and can be removed from the outdoor heat exchanger 130.

In this case, the controller 280 may control the second expansion device 160 such that the opening of the second expansion device 160 is fully opened.

The control unit 280 may control the first expansion device 150 such that a part of the refrigerant passing through the outdoor heat exchanger 130 may be introduced into the indoor heat exchanger 310.

The control unit 280 may control the opening degree of the first expansion device 150 so that the refrigerant may be decompressed and expanded before the inflow of the indoor heat exchanger 310. [

The control unit 280 may control the opening degree of the third expansion device 190 so that the refrigerant can be absorbed and evaporated in the intermediate heat exchanger 140.

The control unit 280 may control the third connection passage opening / closing valve 235 so that a part of the refrigerant passing through the intermediate heat exchanger 140 may be introduced into the accumulator 240.

In the present embodiment, when the degree of impregnation of the outdoor heat exchanger 130 is severe, the refrigerant flow rate of the compressor 110 is increased, and a part of the refrigerant passed through the outdoor heat exchanger 130 flows into the intermediate heat exchanger The defrosting operation time of the outdoor heat exchanger 130 can be remarkably shortened by passing the outdoor heat exchanger 130 via the outdoor heat exchanger 140 and the other part passing through the indoor heat exchanger 310. [

The controller 280 controls the refrigerant passing through the outdoor heat exchanger 130 to flow into the compressor 110 via the indoor heat exchanger 310 and the intermediate heat exchanger 140, And the refrigerant passed through the outdoor heat exchanger 130 is prevented from flowing into the indoor heat exchanger 310. When the defrost operation time is longer than a predetermined time, Or may be controlled to be sucked into the compressor 110 via the intermediate heat exchanger 140 and the accumulator 240.

Hereinafter, another embodiment of the present invention will be described with reference to Figs. 5 to 9. Fig.

As shown in FIG. 5, for example, the refrigeration cycle apparatus of the present embodiment includes a compressor 110; A flow path switching valve 120 provided on the discharge side of the compressor 110; An outdoor heat exchanger (130) connected to the flow path switching valve (120); An indoor heat exchanger 310 connected to the flow path switching valve 120; An intermediate heat exchanger (140) having a first heat exchanging part (142) and a second heat exchanging part (144) and provided between the outdoor heat exchanger (130) and the indoor heat exchanger (310); A first expansion device (150) and a second expansion device (160) provided on both sides of the first heat exchanging part (142); A first connection passage 170 connecting a point between the first heat exchanging part 142 and the first expansion device 150 and the second heat exchanging part 144; A third expansion device 190 provided in the first connection passage 170; A second connection passage 180 connecting the second heat exchange unit 144 and the suction side of the compressor 110; A third connection passage 230 branched from the first connection passage 170; An accumulator 240 provided in the third connection passage 230; An accumulator heat exchanger 250 provided inside the accumulator 240; A fourth connection passage 260 branched from the third connection passage 230 and connected to the accumulator heat exchanger 250; And a fourth expansion device 270 provided in the fourth connection passage 260.

A flow path switching valve 120 for switching a flow path may be provided on the discharge side of the compressor 110.

The outdoor heat exchanger (130) and the indoor heat exchanger (310) may be connected to the flow path switching valve (120).

An intermediate heat exchanger (140) may be provided between the outdoor heat exchanger (130) and the indoor heat exchanger (310).

The intermediate heat exchanger 140 may include a first heat exchanger 142 and a second heat exchanger 144, for example.

A first expansion device (150) and a second expansion device (160) may be provided on both sides of the intermediate heat exchanger (140).

The first heat exchanger 142 is connected to the first heat exchanger 144 and the first heat exchanger 142. The first heat exchanger 142 is connected to the first heat exchanger 144, 170 may be provided.

A third expansion device 190 may be provided in the first connection passage 170.

The second heat exchanging unit 144 may be provided with a second connecting passage 180 so that the refrigerant passing through the second heat exchanging unit 144 can be introduced into the suction side of the compressor 110.

An injection flow path 210 may be formed in the second connection flow path 180 so that the refrigerant passing through the second heat exchange part 144 may be introduced into the intermediate pressure part of the compressor 110.

The second connection passage 180 may be provided with a three-way valve 215 for selectively switching the second connection passage 180 and the injection passage 210.

An accumulator 240 may be installed on the suction side of the compressor 110.

The second connection passage 180 may be connected to the refrigerant passage connecting the accumulator 240 and the compressor 110.

Accordingly, the refrigerant passing through the accumulator 240 and the refrigerant passing through the second heat exchanging unit 144 can be combined and sucked into the suction side of the compressor 110.

The third connection passage 230 is branched into the first connection passage 170 so that the refrigerant passing through the first heat exchange portion 142 of the intermediate heat exchanger 140 can be introduced into the accumulator 240. .

The third connection passage 230 may include a third connection passage opening / closing valve 235 for opening and closing the communication passage.

Meanwhile, the accumulator 240 may be provided with an accumulator heat exchanger 250.

The third connection passage 230 may include a fourth connection passage 260 branched from the accumulator heat exchanger 250 so that the refrigerant passing through the intermediate heat exchanger 140 may flow into the accumulator heat exchanger 250.

A fourth expansion device 270 may be provided in the fourth connection passage 260 so that the refrigerant can be expanded and expanded before the accumulator heat exchanger 250 is introduced.

The fourth expansion device 270 may be embodied as an electronic expansion valve, for example.

Thereby, the fourth expansion device 270 can be controlled by the electric signal.

The outlet side of the accumulator heat exchanger (250) may be connected to the outlet side of the accumulator (240) in a communicating manner.

Meanwhile, as shown in FIG. 9, the refrigeration cycle apparatus of the air conditioner of the present embodiment may include a control unit 280 implemented by a microprocessor having a control program.

The controller 280 controls the refrigerant passing through the outdoor heat exchanger 130 to flow into the compressor 110 via the intermediate heat exchanger 140, for example, during the defrosting operation of the outdoor heat exchanger 130. [ The second expansion device 160, the third expansion device 190, and the fourth expansion device 270 so as to be sucked into the first expansion device 150, the second expansion device 160, the third expansion device 190, and the fourth expansion device 270, respectively.

The controller 280 controls the compressor 110 to cool the refrigerant passing through the outdoor heat exchanger 130 through the indoor heat exchanger 310 during the defrosting operation of the outdoor heat exchanger 130. For example, ). ≪ / RTI >

Accordingly, since the refrigerant does not flow into the indoor heat exchanger (310), generation of cold air by the refrigerant in the indoor heat exchanger (310) can be suppressed.

Thus, the occurrence of the temperature drop in the room due to the generation of the cold air of the indoor heat exchanger 310 can be suppressed.

Also, since the refrigerant passed through the outdoor heat exchanger 130 does not flow through the indoor heat exchanger 310, the circulation path of the refrigerant can be remarkably shortened.

As a result, the defrosting operation time of the outdoor heat exchanger 130 can be remarkably shortened.

In addition, since the refrigerant passed through the outdoor heat exchanger 130 does not pass through the indoor heat exchanger 310, generation of refrigerant flow noise in the room can be suppressed.

For example, the conception detecting unit 285 that senses the conception of the outdoor heat exchanger 130 may be communicatively connected to the control unit 280.

The control unit 280 controls the flow path of the refrigerant passed through the outdoor heat exchanger 130 according to the degree of conception of the outdoor heat exchanger 130 sensed by the conception sensing unit 285, Lt; / RTI >

The control unit 280 distinguishes, for example, the degree of conception of the outdoor heat exchanger 130 sensed by the conception sensing unit 285 by a plurality of setting levels, The flow path of the refrigerant via the heat exchanger 130 can be controlled differently.

The conception sensing unit 285 may be configured to sense the degree of conception of the outdoor heat exchanger 130 based on, for example, the piping temperature of the outdoor heat exchanger 130.

The frost detection unit 285 detects the outdoor heat exchanging operation in consideration of the outdoor temperature and the piping temperature of the outdoor heat exchanger 130 and / or the cumulative operation time of the outdoor heat exchanger 130 below the freezing point, And may be configured to detect the degree of implantation of the device 130.

 The control unit 280 controls the operation of the outdoor heat exchanger 130 when the degree of impregnation of the outdoor heat exchanger 130 sensed by the conception sensing unit 285 is equal to or lower than the first setting level The first expansion device 150, the second expansion device 160, the third expansion device 160, the third expansion device 160, and the third expansion device 160, so that the refrigerant is sucked into the compressor 110 via the intermediate heat exchanger 140 without passing through the indoor heat exchanger 310. [ The expansion device 190 and the fourth expansion device 270, respectively.

The control unit 280 controls the outdoor heat exchanger 130 such that when the degree of conception of the outdoor heat exchanger 130 sensed by the conception sensing unit 285 exceeds the first setting level and is equal to or lower than the second setting level, The refrigerant passing through the compressor 130 is sucked into the compressor 110 via the intermediate heat exchanger 140 and the accumulator heat exchanger 250 without passing through the indoor heat exchanger 310, The expansion device 150, the second expansion device 160, the third expansion device 190, and the fourth expansion device 270, respectively.

The control unit 280 may control the outdoor heat exchanger 130 to cool the outdoor heat exchanger 130 when the degree of impregnation of the outdoor heat exchanger 130 sensed by the conception sensing unit 285 exceeds a second predetermined level, The refrigerant passed through the intermediate heat exchanger 140, the accumulator heat exchanger 250 and the indoor heat exchanger 310 is sucked into the compressor 110 through the first expansion device 150, the second expansion device 150, The expansion device 160, the third expansion device 190, and the fourth expansion device 270, respectively.

6, the control unit 280 determines whether the degree of impregnation of the outdoor heat exchanger 130 sensed by the conception sensing unit 285 is greater than or equal to a first predetermined level The flow path switching valve 120 can be controlled so that the refrigerant discharged from the compressor 110 flows into the outdoor heat exchanger 130. [

The controller 280 controls the refrigerant passing through the outdoor heat exchanger 130 to flow through the intermediate heat exchanger 140 while the indoor heat exchanger 310 does not pass the first expansion It is possible to control the apparatus 150, the second expansion device 160, the third expansion device 190 and the fourth expansion device 270, and the three-way valve 215, respectively.

The control unit 280 controls the second expansion device 160 to be opened all over and the first expansion device 150 controls to shut off the flow path.

The control unit 280 controls the refrigerant to be decompressed and expanded in the third expansion device 190 and controls the third connection passage opening / closing valve 235 and the fourth expansion device 270 to be blocked .

The control unit 280 may control the three-way valve 215 so that the injection flow path 210 is blocked and the second connection flow path 180 is opened.

Thus, the refrigerant passed through the outdoor heat exchanger 130 is expanded under pressure by the third expansion device 190 through the first heat exchange portion 142 of the intermediate heat exchanger 140, Can absorb the latent heat in the evaporator 144 and evaporate.

The refrigerant passed through the second heat exchanging unit 144 is evaporated and then sucked to the suction side of the compressor 110 and discharged to the outdoor heat exchanger 130 repeatedly while being compressed and discharged by the compressor 110. [ Can be performed.

7, when the degree of conception of the outdoor heat exchanger 130 sensed by the conception sensing unit 285 exceeds the first set level and the degree of conception of the outdoor heat exchanger 130 exceeds the first predetermined level, The refrigerant passing through the outdoor heat exchanger 130 is not passed through the indoor heat exchanger 310 but flows through the intermediate heat exchanger 140 and the accumulator heat exchanger 250 to the compressor The third expansion device 190 and the fourth expansion device 270 and the three-way valve 215 so as to be sucked into the first expansion device 150, the second expansion device 160, the third expansion device 190, have.

The control unit 280 controls the second expansion device 160 to be expanded so that the first expansion device 150 controls the flow path to be shut off and the third connection path 230 is opened It is possible to control the three-way flow opening / closing valve 235.

The controller 280 controls the opening degree of the third expansion device 190 and the fourth expansion device 270 so that the refrigerant can be decompressed and expanded before the inflow of the intermediate heat exchanger 140 and the accumulator heat exchanger 250 Respectively.

As a result, the refrigerant passed through the outdoor heat exchanger 130 passes through the first heat exchanger 142 of the intermediate heat exchanger 140, and a part of the refrigerant is expanded under pressure in the third expansion device 190, May be decompressed and expanded in the fourth expansion device (270).

The refrigerant expanded in the third expansion device (190) can be evaporated by absorbing the latent heat in the second heat exchanger (144) of the intermediate heat exchanger (140).

The refrigerant expanded in the fourth expansion device (270) can be evaporated by absorbing the latent heat in the accumulator heat exchanger (250).

The refrigerant evaporated in the second heat exchanging unit 144 moves along the second connecting passage 180 and the refrigerant evaporated in the accumulator heat exchanger 250 moves along the refrigerant passage, May be combined with the refrigerant moved along the refrigerant pipe 180 and sucked into the compressor 110.

Since the refrigerant passing through the outdoor heat exchanger 130 passes through the intermediate heat exchanger 140 and the accumulator heat exchanger 250 and does not flow through the indoor heat exchanger 310, The path can be remarkably shortened.

Since the refrigerant passed through the outdoor heat exchanger 130 is evaporated in the intermediate heat exchanger 140 and the accumulator heat exchanger 250, the flow rate of the refrigerant can be increased, The defrosting time can be prevented from being prolonged and the defrosting operation time can be shortened.

The refrigerant having a relatively high temperature via the first heat exchanger 142 of the intermediate heat exchanger 140 flows into the accumulator 240 along the third connection passage 230, The temperature of the inside of the accumulator 240 can be increased and the evaporation of the refrigerant in the accumulator 240 can be promoted.

8, when the degree of impregnation of the outdoor heat exchanger 130 sensed by the conception detecting unit 285 exceeds the second setting level (for example, as shown in FIG. 8) The refrigerant passed through the outdoor heat exchanger 130 is sucked into the compressor 110 via the intermediate heat exchanger 140, the accumulator heat exchanger 250 and the indoor heat exchanger 310, It is possible to control the first expansion device 150, the second expansion device 160, the third expansion device 190 and the fourth expansion device 270, and the three-way valve 215, respectively.

More specifically, the control unit 280 controls the second expansion device 160 to be fully opened when the degree of impregnation of the outdoor heat exchanger 130 exceeds the second set level, The first expansion device (150) can control the refrigerant to be decompressed and expanded.

The control unit 280 further includes a third expansion device 190 and a fourth expansion device 270 so that the refrigerant in the third expansion device 190 and the fourth expansion device 270 can be decompressed and expanded, Respectively.

The control unit 280 controls the third connection passage opening and closing valve 235 to open the third connection passage 230 and the refrigerant passed through the second heat exchange unit 144 flows into the compressor 110, Way valve 215 so as to flow to the suction side of the injection valve 210 and shut off the injection flow path 210.

The refrigerant that has been discharged from the outdoor heat exchanger 130 and has performed the defrosting operation passes through the first heat exchanging portion 142 of the intermediate heat exchanger 140 and a part of the refrigerant passes through the first connecting flow path 170 And a part of the refrigerant can be moved to the indoor heat exchanger 310.

A part of the refrigerant in the first connection passage 170 is expanded and expanded in the third expansion device 190 while the other part is moved along the third connection passage 230 and the fourth connection passage 260 .

The refrigerant that has been moved along the fourth connection passage 260 may be decompressed and expanded in the fourth expansion device 270.

The refrigerant expanded in the third expansion device (190) can be evaporated by absorbing latent heat in the second heat exchange part (144).

The refrigerant expanded in the fourth expansion device (270) can be evaporated by absorbing the latent heat in the accumulator heat exchanger (250).

The refrigerant decompressed and expanded in the first expansion device (150) can be evaporated by absorbing latent heat in the indoor heat exchanger (310).

The refrigerant evaporated in the second heat exchanger 144 is moved to the suction side of the compressor 110 and the refrigerant evaporated in the accumulator heat exchanger 250 can be moved to the outlet side of the accumulator 240.

The refrigerant evaporated in the indoor heat exchanger 310 may be combined with the refrigerant moved along the third connection passage 230 and may be introduced into the accumulator 240.

The refrigerant flowing into the accumulator 240 is separated into a liquid and a liquid, and the gaseous refrigerant flows out to the outlet side of the accumulator 240, merges with the refrigerant evaporated in the accumulator 240, Can be moved to the compressor (110).

The refrigerant traveling to the compressor 110 merges with the refrigerant evaporated in the second heat exchanging unit 144 and is sucked into the suction side of the compressor 110. The compressor 110 discharges the refrigerant compressed and discharged The defrosting operation of the outdoor heat exchanger 130 can be performed.

According to the present embodiment, even when the degree of impregnation of the outdoor heat exchanger 130 is relatively high, the flow rate of circulated refrigerant is increased, and the refrigerant passed through the outdoor heat exchanger 130 flows through the intermediate heat exchanger 140, The defrosting operation of the outdoor heat exchanger 130 can be shortened even in the case where the evaporator is evaporated in the accumulator heat exchanger 250 and the indoor heat exchanger 310 respectively.

Although the third connection path opening / closing valve 235 is provided on the upstream side of the branch point of the fourth connection path 260 in the above-described embodiment and the illustrated embodiment, this is merely an example, And the third connection passage opening / closing valve 235 may be disposed on the downstream side of the branch point of the fourth connection passage.

In this case, the control unit 280 causes some of the refrigerant passed through the intermediate heat exchanger 140 to flow to the second heat exchanger 144 of the intermediate heat exchanger 140, Or the accumulator 240 and the accumulator heat exchanger 250 so as to allow the fourth expansion device 270 and the third connection 250 to flow into the accumulator 240 and the accumulator 240, And the flow control valve 235 can be controlled.

The foregoing has been shown and described with respect to specific embodiments of the invention. However, the present invention may be embodied in various forms without departing from the spirit or essential characteristics thereof, so that the above-described embodiments should not be limited by the details of the detailed description.

Further, even when the embodiments not listed in the detailed description have been described, it should be interpreted broadly within the scope of the technical idea defined in the appended claims. It is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

100: outdoor unit 110: compressor
120: Flow path switching valve 130: Outdoor heat exchanger
135: outdoor fan 140: intermediate heat exchanger
142: first heat exchanger 144: second heat exchanger
150: first expansion device 160: second expansion device
170: first connection channel 180: second connection channel
190: third expansion device 210: injection valve
215: three-way valve 230: third connection channel
235: third connecting passage opening / closing valve 240: accumulator
250: accumulator heat exchanger 260: fourth connection channel
270: fourth expansion device 280:
285:

Claims (15)

compressor;
A flow path switching valve provided on a discharge side of the compressor;
An outdoor heat exchanger connected to the flow path switching valve;
An indoor heat exchanger connected to the flow path switching valve;
An intermediate heat exchanger having a first heat exchanger and a second heat exchanger, the intermediate heat exchanger being disposed between the outdoor heat exchanger and the indoor heat exchanger;
A first expansion device and a second expansion device provided on both sides of the first heat exchanger;
A first connection passage connecting a point between the first heat exchanger and the first expansion device and the second heat exchanger;
A second connection passage connecting the second heat exchange unit and the suction side of the compressor;
A third expansion device provided in the first connection passage;
An accumulator provided on a suction side of the compressor;
A third connection passage branched from the first connection passage and connected to the suction side of the accumulator;
A third connection passage opening / closing valve for opening / closing the third connection passage; And
And a controller for controlling the first expansion device, the second expansion device, and the third expansion device, respectively, in the defrosting operation of the outdoor heat exchanger,
Wherein,
The second expansion device, and the second expansion device such that at least a part of the refrigerant passed through the outdoor heat exchanger is sucked into the compressor via the intermediate heat exchanger and the second connection passage during the defrosting operation of the outdoor heat exchanger, 3 expansion device, respectively,
Wherein when the predetermined time elapses during the defrosting operation of the outdoor heat exchanger, at least a part of the refrigerant passed through the outdoor heat exchanger is sucked into the compressor via the third connection passage and the accumulator, Wherein the control unit controls the operation of the air conditioner. delete delete The method according to claim 1,
And an injection flow branching from the second connection passage and flowing into the intermediate pressure portion of the compressor. 5. The method of claim 4,
And a three-way valve for selectively opening and closing the second connection passage and the injection passage. delete The method according to claim 1,
And a conception detecting unit for sensing conception of the outdoor heat exchanger,
Wherein the control unit is configured to allow the refrigerant of the outdoor heat exchanger to be sucked into the compressor via the intermediate heat exchanger when the degree of impregnation of the outdoor heat exchanger is equal to or lower than a first set level based on the detection result of the conception detecting unit,
The first expansion device, the second expansion device, and the second expansion device, so that the refrigerant passed through the outdoor heat exchanger is sucked into the compressor via the indoor heat exchanger and the intermediate heat exchanger, respectively, And the third expansion device are respectively controlled by the first expansion device and the second expansion device. compressor;
A flow path switching valve provided on a discharge side of the compressor;
An outdoor heat exchanger connected to the flow path switching valve;
An indoor heat exchanger connected to the flow path switching valve;
An intermediate heat exchanger having a first heat exchanger and a second heat exchanger, the intermediate heat exchanger being disposed between the outdoor heat exchanger and the indoor heat exchanger;
A first expansion device and a second expansion device provided on both sides of the first heat exchanger;
A first connection passage connecting a point between the first heat exchanger and the first expansion device and the second heat exchanger;
A third expansion device provided in the first connection passage;
A second connection passage connecting the second heat exchange unit and the suction side of the compressor;
A third connection passage branched from the first connection passage;
A third connection passage opening / closing valve provided in the third connection passage for opening / closing the third connection passage;
An accumulator provided in the third connection passage;
An accumulator heat exchanger provided inside the accumulator;
A fourth connection passage branched from the third connection passage and connected to the accumulator heat exchanger;
A fourth expansion device provided in the fourth connection passage;
A control unit for controlling the first expansion device, the second expansion device, the third expansion device, and the fourth expansion device, respectively, in the defrosting operation of the outdoor heat exchanger; And
And a conception detecting unit for sensing conception of the outdoor heat exchanger,
Wherein,
Based on the detection result of the conception detecting section,
The refrigerant of the outdoor heat exchanger is sucked into the compressor via the intermediate heat exchanger and the second connection passage when the degree of impregnation of the outdoor heat exchanger is equal to or lower than the first set level,
When the degree of impregnation of the outdoor heat exchanger exceeds the first set level and is equal to or lower than the second set level, the refrigerant passed through the outdoor heat exchanger passes through the second connection passage, the third connection passage and the fourth connection passage And to be sucked into the compressor,
The refrigerant passed through the outdoor heat exchanger flows through the second connection passage, the third connection passage, the fourth connection passage, and the indoor heat exchanger via the outdoor heat exchanger, respectively, when the degree of impregnation of the outdoor heat exchanger exceeds the second set level To be sucked into the compressor,
And controls the first expansion device, the second expansion device, the third expansion device, and the fourth expansion device, respectively. delete 9. The method of claim 8,
And an injection flow branching from the second connection passage and flowing into the intermediate pressure portion of the compressor. 11. The method of claim 10,
And a three-way valve provided in the branching region of the second connection passage and the injection passage for selectively opening and closing the second connection passage and the injection passage. delete delete delete delete

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