KR101186331B1 - Multi-air conditioner for heating and cooling operations at the same time - Google Patents

Abstract

The present invention is installed on the low-pressure gas pipe in order to control the amount of refrigerant that can be introduced to each other between the plurality of outdoor units through the low-pressure gas pipe during the heating room operation of the heating and cooling simultaneous multi-air conditioner simultaneous operation of the heating subject. Since the air-conditioning simultaneous multi-air conditioner including the first and second flow control valves is provided, the flow rate of the refrigerant between the outdoor units can be efficiently controlled, and the compressor discharge temperature of the plurality of outdoor units can be kept constant. have.

Cooling and heating simultaneous multi air conditioner, heating room operation, heating subject simultaneous operation, air conditioning chamber operation, cooling subject simultaneous operation, electronic expansion valve

Description

Multi-air conditioner for heating and cooling operations at the same time}

1 is a schematic diagram of a cooling and heating simultaneous multi air conditioner according to an embodiment of the present invention.

FIG. 2 is an operation diagram illustrating an operating state of the air-conditioning simultaneous multi air conditioner of FIG.

3 is an operation diagram showing an operating state of the air-conditioning simultaneous multi air conditioner of FIG.

4 is an operation diagram showing an operating state of the air-conditioning simultaneous multi air conditioner of FIG.

5 is an operation diagram showing an operating state of the air-conditioning simultaneous multi air conditioner of FIG.

BRIEF DESCRIPTION OF THE DRAWINGS Fig.

A1: Main outdoor unit for both air conditioning and heating A2: Sub outdoor unit for both air conditioning and heating

B1, B2, B3, B4: Indoor 1,2,3,4 combined air conditioning

C: Splitter

11,21,31,41: 1,2,3,4 indoor heat exchanger

12,22,32,42: 1,2,3,4 indoor electromagnetic expansion valve

13,23,33,43: 1,2,3,4 indoor connection pipe

14,24,34,44: 5,6,7,8 indoor connection pipe

15,25,35,45: 1, 2, 3, 4 indoor unit fan

51,51 ': Outdoor heat exchanger of main outdoor unit, outdoor heat exchanger of sub outdoor unit

53,54: main outdoor unit compressor

53 ', 54': Compressor of sub outdoor unit

61,61 ': fan of main outdoor unit and sub outdoor unit

62,62 ': Four-way valve of main outdoor unit and sub outdoor unit

63,63 ': High pressure gas pipe 64,64': Suction pipe

65,65 ': Outdoor electromagnetic expansion valve 72,72': Liquid piping

75,75 ': Low pressure gas pipe 81: High pressure gas header

82: low pressure gas header 83: liquid header

90,90 ': 1st and 2nd flow control valve

91,91 ': 1st and 2nd open / close valve

92,92 ': 1st and 2nd bypass piping

100: simultaneous heating and cooling multi air conditioner

The present invention relates to a simultaneous air-conditioning multi air conditioner, and more particularly, to a simultaneous air-conditioning-type multi air conditioner, in which a flow rate control valve is installed on a low pressure gas pipe connected to an outdoor unit to effectively distribute a flow rate of a refrigerant during an outdoor period. It is about.

In general, a multi-type air conditioner connects a plurality of indoor units to one outdoor unit, and each of the plurality of indoor units is used as a cooler or a heater while using the outdoor unit in common.

Recently, a plurality of compressors are provided or a plurality of outdoor units are connected to each other in parallel so as to effectively cope with cooling or heating loads according to the number of indoor units.

The multi-air conditioner according to the prior art includes a plurality of outdoor units, a plurality of indoor units, and a refrigerant pipe connecting the plurality of outdoor units and indoor units, wherein the plurality of outdoor units are a main outdoor unit and a plurality of sub units. It consists of an outdoor unit.

Each of the plurality of outdoor units includes a compressor for compressing a low-temperature, low-pressure gaseous refrigerant to high temperature and high pressure, an outdoor heat exchanger for exchanging circulated refrigerant with outdoor air, and a four-way valve for switching refrigerant flow according to cooling or heating operation. Is installed. Each of the plurality of indoor units is provided with an expansion mechanism and an indoor heat exchanger for heat-exchanging refrigerant circulated with indoor air.

In the multi-air conditioner according to the related art, the refrigerant compressed by the compressor of the main outdoor unit and the sub outdoor unit is sent to the outdoor heat exchanger by the four-way valve during the cooling operation, and the refrigerant passing through the outdoor heat exchanger After condensation by heat exchange with air, it is sent to the expansion mechanism. The refrigerant expanded in the expansion mechanism flows into the indoor heat exchanger and evaporates while absorbing heat of indoor air, thereby cooling the room.

In the heating operation, the flow path is switched in the four-way valve, and the refrigerant discharged from the compressor passes through the four-way valve, the indoor heat exchanger, the outdoor linear expansion valve (LEV), and the outdoor heat exchanger in order. Will be heated.

However, in the conventional air-conditioning simultaneous multi-air conditioner, the flow rate of the refrigerant is controlled only by the control of the outdoor electromagnetic expansion valve during the heating of the entire room. Even though the outdoor electromagnetic expansion valve of the main outdoor unit is closed a lot, the refrigerant through the sub outdoor unit is used. Although the refrigerant is transferred to the main outdoor unit through the low pressure gas pipe or the outdoor electromagnetic expansion valve of the sub outdoor unit is closed a lot, the refrigerant through the main outdoor unit is transferred to the sub outdoor unit through the low pressure gas pipe to flow the refrigerant flow between the plurality of outdoor units. There is a problem that the distribution is not effective.

In addition, during the operation of the heating main body, while the refrigerant is introduced from the indoor unit and transferred to the main outdoor unit or the sub outdoor unit, even the refrigerant which should be introduced to the other outdoor unit is also introduced into a specific outdoor unit, thereby imbalance in the flow distribution of the refrigerant between the plurality of outdoor units. There is a problem that occurs.

An object of the present invention is to provide a cooling and heating simultaneous multi air conditioner that can effectively distribute the flow rate of the refrigerant during the outdoor period by installing a flow control valve on the low pressure gas pipe connected to the outdoor unit.

The present invention is installed on the low pressure gas pipes connected to the suction portions of the plurality of compressors to control the flow rate of the refrigerant between the plurality of outdoor units during the heating of all the room operation or heating subjects at the same time to control the flow rate of the refrigerant It provides a heating and cooling simultaneous multi air conditioner including a flow control unit.

According to another aspect of the present invention, the first and second flow control valves of the present invention are first and second electromagnetic expansion valves, respectively, and bypass the refrigerant flowing into the first and second flow control valves on the low pressure gas pipe. It provides a first and second bypass pipes, and the air conditioning simultaneous multi air conditioner further comprises a first and second on-off valves installed on the first and second bypass pipes.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a schematic diagram of a cooling and heating simultaneous multi air conditioner according to an embodiment of the present invention.

The air-conditioning simultaneous multi air conditioner 100 includes first, second, third and fourth air-conditioning combined indoor units B1, B2, B3 and B4, air-conditioning combined outdoor units A1, A2 and a distributor C. .

The combined outdoor air conditioners A1 and A2 are composed of a main outdoor unit A1 and a sub outdoor unit A2, and the first and second compressors 53, 54, 53 ′, 54 ′ and the outdoor heat exchanger 51, respectively. 51 '), outdoor heat exchanger fans 61, 61' and a switching unit. Here, the switching unit includes four-way valves 62 and 62 '. Hereinafter, each component will be described with reference to the main outdoor unit A1.

The compressor of the main outdoor unit is composed of first and second compressors 53 and 54, and the compressor of the sub outdoor unit is composed of first and second compressors 53 'and 54'. As described above, the suction unit of the first and second compressors 53 and 54 is connected by a common accumulator 52. The first compressor 53 is an inverter compressor capable of varying the compression capacity of the refrigerant, and the second compressor 54 is a constant speed compressor having a constant compression capacity of the refrigerant.

First and second discharge pipes 55 and 56 are connected to discharge parts of the first and second compressors 53 and 54, and the first and second discharge pipes 55 and 56 are connected to the lamination part 57. By the first and second discharge pipes 55 and 56, the first and second oil separators 58 and 59 are configured to recover oil from the refrigerant discharged from the first and second compressors 53 and 54. Each is installed. In the first and second oil separators 58 and 59, the first and second oil separators 58 and 59 guide oil separated from the first and second oil separators 58 and 59 to the suction part of the first and second compressors 53 and 54. , 2 oil recovery pipes 30 and 31 are connected.

The high pressure gas pipe 63 for connecting the refrigerant discharged from the first and second compressors 53 and 54 to bypass the four-way valve 62 is connected to the lamination part 57a. In addition, the lamination portion 57 is connected to the four-way valve 57 and the third discharge pipe (68).

The outdoor heat exchanger 51 is connected to the four-way valve 62 by the first connection pipe 71. In the outdoor heat exchanger 51, the refrigerant is condensed or evaporated by heat exchange with outside air. At this time, in order to make the heat exchange more smoothly, the outdoor unit fan 61 flows air into the outdoor heat exchanger 51. In the air-conditioning simultaneous multi air conditioner (100), the outdoor heat exchanger (51) is used as the condenser during the cooling room operation or the simultaneous operation of the cooling main body. Used as

On the liquid pipe 72 connecting the outdoor heat exchanger 51 and the distributor C, an outdoor electromagnetic expansion valve 65 and a supercooling device 66 are provided. The outdoor electromagnetic window valve 65 expands the refrigerant during the heating of all the rooms or the simultaneous operation of the heating subjects. The supercooling device 66 cools the refrigerant moved to the distributor C during the cooling chamber operation or the simultaneous operation of the cooling main body. The outdoor electromagnetic expansion valve 65 transfers the refrigerant condensed in the first, second, third, and fourth indoor heat exchangers 11, 21, 32, and 41 to the outdoor heat exchanger 51 during all the heating operation or simultaneous heating operation. Inflate before entering. The subcooler 66 is configured to cover a portion of the liquid pipe 72, and a portion of the refrigerant that is disposed between the subcooler 66a and the distributor C and moves to the distributor C. Bypass piping 66b for bypassing the subcooler 66a, electromagnetic expansion valve 66c provided in the bypass piping 66b, and subcooler 66a and the third discharge pipe 64 are connected. And a recovery pipe 66d.

Meanwhile, the air-conditioning simultaneous multi air conditioner according to the present invention includes a flow rate control part installed on the low pressure gas pipe connected to the suction parts of the plurality of compressors to control the flow rate of the refrigerant, which is included in the main outdoor unit A1. The first flow rate control valve 90 installed on the connected low pressure gas pipe 75 and the second flow rate control valve 90 'installed on the low pressure gas pipe 75' connected to the sub outdoor unit A2.

During the heating and heating operation of the heating / cooling simultaneous multi air conditioner 100 or the simultaneous heating subject operation, the refrigerant flows into the sub outdoor unit A2 through the low pressure gas pipe 75 connected to the main outdoor unit A1, or The refrigerant may flow into the main outdoor unit A1 through the low pressure gas pipe 75 'connected to the sub outdoor unit A2.

That is, when the heating room is operated, it is preferable that the refrigerant is not transferred through the low pressure gas pipes 75 and 75 ', but the refrigerant introduced into the main outdoor unit A1 through the liquid pipe 72 is In the process of flowing into the accumulator 52 through the four-way valve 62, the refrigerant may be delivered to the low pressure gas pipe 75, the refrigerant delivered to the low pressure gas pipe 75 is the sub outdoor unit (A2) It may be delivered to the sub outdoor unit (A2) through the low pressure gas pipe (75 ') connected to the) side.

The reason for this is generally to control the opening values of the outdoor electromagnetic expansion valves 65 and 65 'of the main outdoor unit A1 and the sub outdoor unit A2 to maintain the discharge temperature of the compressor at a constant temperature. When the discharge temperatures of the compressors 53, 54, 53 ′ and 54 ′ of the outdoor units A1 and A2 are low, in order to reduce the amount of refrigerant flowing into the outdoor units A1 and A2, the outdoor units A1 and A2 may be discharged. If the discharge temperature of the compressors 53, 54, 53 'and 54' of the outdoor units A1 and A2 is high, the outdoor unit A1 and A2 are controlled to close the outdoor electromagnetic expansion valves 65 and 65 '. This is because the outdoor electromagnetic expansion valves 65 and 65 'of the outdoor units A1 and A2 are opened in order to increase the amount of refrigerant flowing into).

In the process of performing the refrigerant distribution control between the outdoor units A1 and A2 as described above, the outdoor electromagnetic expansion valve 65 of the main outdoor unit A1 is closed and the outdoor electromagnetic expansion valve 65 of the sub outdoor unit A2 is closed. ') Is opened or the outdoor electromagnetic expansion valve 65 of the main outdoor unit A1 is opened and the outdoor electromagnetic expansion valve 65' of the sub outdoor unit A2 is closed.

At this time, even if the outdoor electromagnetic expansion valve 65 of the main outdoor unit A1 is closed, the refrigerant in the sub outdoor unit A2 may flow into the main outdoor unit A1 through the low pressure gas pipe 75 '. On the contrary, even if the outdoor electromagnetic expansion valve 65 'of the sub outdoor unit A2 is closed, the refrigerant in the main outdoor unit A1 may flow into the sub outdoor unit A2 through the low pressure gas pipe 75.

Therefore, the discharge temperature of the compressors 53, 54, 53 ', 54' is kept constant only by controlling the opening values of the outdoor electromagnetic expansion valves 65, 65 'of the main outdoor unit A1 and the sub outdoor unit A2. There is a case where control is impossible.

When the outdoor electromagnetic expansion valve 65 of the main outdoor unit A1 is closed in order to prevent the above case and maintain the discharge temperature of the compressors 53, 54, 53 ′, 54 ′, the sub The first flow control valve 90 is closed to prevent refrigerant from being transferred to the main outdoor unit A1 through the low pressure gas pipe 75 'connected to the outdoor unit A2.

On the contrary, when closing the outdoor electromagnetic expansion valve 65 'of the sub outdoor unit A2, the refrigerant flows into the sub outdoor unit A2 through the low pressure gas pipe 75 connected to the main outdoor unit A1. The second flow control valve 90 'is closed so as not to be delivered.

On the other hand, during simultaneous operation of the heating subject, the refrigerant flows into the outdoor units A1 and A2 through the low pressure gas pipes 75 and 75 '. In particular, when the ratio of the capacity of the indoor unit B4 to be cooled is less than the set value, due to the strong compression force of the compressors 53 'and 54' of the sub outdoor unit A2, through the low pressure gas pipe 75 '. The refrigerant delivered to the suction pipe 64 ′ of the sub outdoor unit A2 increases, and at this time, even the refrigerant to be transferred to the suction pipe 64 of the main outdoor unit A1 is suction pipe of the sub outdoor unit A2. 64 '. Similarly, even when there is a lot of refrigerant delivered to the suction pipe 64 of the main outdoor unit A1 through the low pressure gas pipe 75 due to the strong compression force of the main compressors 53 and 54 of the main outdoor unit A1. The refrigerant to be delivered to the suction pipe 64 ′ of the sub outdoor unit A2 may be transferred to the suction pipe 64 of the main outdoor unit A1.

Therefore, the first and second flow control valves 90 and 90 'are controlled to maintain a constant discharge temperature of the compressor to prevent the above case. That is, when the amount of refrigerant delivered to the suction pipe 64 'of the sub outdoor unit A2 through the low pressure gas pipe 75' is large, the second flow control valve 90 'is closed by a predetermined value. The first flow rate control valve 90 is controlled to open by a predetermined value.

Similarly, if the amount of refrigerant delivered to the suction pipe 64 of the main outdoor unit A1 through the low pressure gas pipe 75 is large, the first flow control valve 90 is controlled to close by a predetermined value. The second flow control valve 90 'is controlled to open by a predetermined value.

Meanwhile, the first and second flow control valves 90 and 90 'are constituted by first and second linear expansion valves (LEVs), respectively, and on the low pressure gas pipes 75 and 75', respectively. 2 and 2 bypass pipes 92 installed in parallel with the 2 flow control valves 90 and 90 'to bypass the refrigerant flowing into the 1 and 2 flow control valves 90 and 90'. 92 'and first and second open / close valves 91 and 91' provided on the first and second bypass pipes 92 and 92 '. Here, the first and second open / close valves 91 and 91 'are configured as solenoid valves to enable control by an electric signal.

The distributor C is disposed between the air-conditioning combined outdoor units A1 and A2 and the first, second, third and fourth indoor units B1, B2, B3 and B4, and the air-conditioning room, the heating room, The refrigerant is distributed to the first, second, third, and fourth combined indoor units B1, B2, B3, and B4 according to the cooling subject simultaneously and the simultaneous heating subject operating conditions. That is, between the main outdoor unit (A1) and the sub outdoor unit (A2) and the indoor units (B1) (B2) (B3) (B4) is disposed between the cooling and cooling according to the operating conditions of the air conditioner-type multi air conditioner Can be controlled. Dispenser C here comprises a high pressure gas header 81, a low pressure gas header 82, a liquid header 83 and control valves (not shown).

The first, second, third and fourth indoor units B1, B2, B3, and B4 are the first, second, third and fourth indoor heat exchangers 11, 21, 31, and 41, respectively. 1, 2, 3, 4 indoor expansion valves 12, 22, 32, 42 and 1, 2, 3, 4 indoor fans 15, 25, 35, 45 Include. The first, second, third and fourth indoor electromagnetic expansion valves 12, 22, 32 and 42 are first, second, third and fourth indoor heat exchangers 11, 21, 31 and 41. And the first, second, third and fourth indoor connection pipes 13, 23, 33 and 43 for connecting the high pressure gas header 81 to each other.

The high pressure gas header 81 is connected to one side of the high pressure gas pipe 63 of the lamination part 57 and the first, second, third and fourth indoor heat exchangers 11, 21, 31 and 41, respectively. do. In addition, the low pressure gas header 82 is connected to the suction pipe 64 by the low pressure gas pipe 75, and the first, second, third and fourth indoor heat exchangers 11, 21, 31 and 41 It is connected to the other side. The liquid header 83 is connected to one side of the subcooler 66 and the first, second, third and fourth indoor heat exchangers 11, 21, 31 and 41, respectively. Here, the high pressure gas header 81, the low pressure gas header 82, and the liquid header 83 have a high pressure gas pipe 63 ', a low pressure gas pipe 75', and a liquid pipe 72 'of another sub outdoor unit A2. Each of these is further connected.

In this case, when the heating room or the heating main body of the air conditioner simultaneous multi-air conditioner 100 is operated at the same time, the low pressure gas pipes 75 and 75 'may supply the refrigerant in the low pressure gas header 82 to the main outdoor unit A1. To the suction pipe 64 of the sub outdoor unit A2 or the suction pipe 64 'of the sub outdoor unit A2, and the liquid pipes 72 and 72' direct the refrigerant in the liquid header 83 to the main outdoor unit A1. It guides to the outdoor electromagnetic expansion valve 65 or the outdoor electromagnetic expansion valve 65 'of the sub outdoor unit A2. In addition, the high-pressure gas pipes (63, 63 ') is a high-pressure gas refrigerant discharged from the compressors (53, 54, 53', 54 ') of the outdoor units (A1, A2) the indoor units (B1, B2, B3). , B4).

2 to 5, the operation of the air-conditioning simultaneous multi air conditioner shown in FIG. 1 and the flow of the refrigerant according to this will be described.

Figure 2 shows the operation of the air-conditioning simultaneous multi-air conditioner 100 and the flow of the refrigerant according to the heating in all the room operation. Here, the flow of the coolant in the main outdoor unit A1 will be limited. The refrigerant of the high pressure gas discharged from the first and second compressors 53 and 54 flows through the first and second discharge pipes 55 and 56 and does not flow into the four-way valve 62, but the lamination part 57 and The high pressure gas pipe 63 passes through the high pressure gas header 81. The refrigerant discharged from the high-pressure gas header 81 through the fifth, sixth, seventh and eighth indoor connection pipes 14, 24, 34 and 44 may be the first, second, third and fourth indoor heat exchangers. Condensation at (11) (21) (31) (41). Thereafter, the refrigerant flows into the liquid header 83, is discharged through the liquid pipes 72 and 72 ', and flows into the outdoor electromagnetic expansion valves 65 and 65'. Herein, the outdoor electromagnetic expansion valves 65 and 65 'of the main outdoor unit A1 and the sub outdoor unit A2 have a predetermined opening value to maintain a constant discharge temperature of the compressors 53, 54, 53', and 54 '. Refrigerant discharged through the liquid pipes 72 and 72 'is distributed to the outdoor electromagnetic expansion valves 65 and 65' and flows in.

The refrigerant expanded in the outdoor electromagnetic expansion valves 65 and 65 'is evaporated in the outdoor heat exchangers 51 and 51'. The low temperature low pressure gas refrigerant flows into the suction pipes 64 and 64 'via the four-way valves 62 and 62', and then through the accumulators 52 and 52 ', the first and second compressors 53 and 53' (54). 54 ').

Here, when the refrigerant is distributed to the outdoor electromagnetic expansion valve (65, 65 '), the main outdoor unit (A1) and the main outdoor unit (A1) to maintain the discharge temperature of the compressor (53, 54, 53', 54 ') at a constant temperature; Control is made to determine the opening value of the outdoor electromagnetic expansion valves 65, 65 'of the sub outdoor unit A2, which is discharged from the compressors 53, 54, 53', 54 'of the outdoor units A1, A2. When the temperature is low, in order to reduce the amount of refrigerant flowing into the outdoor units A1 and A2, a control is performed to close the outdoor electromagnetic expansion valves 65 and 65 'of the outdoor units A1 and A2, and conversely, the outdoor units A1. When the discharge temperatures of the compressors 53, 54, 53 ', and 54' of A2 are high, the outdoor electromagnetic expansion valves of the outdoor units A1 and A2 to increase the amount of refrigerant flowing into the outdoor units A1 and A2, 65, 65 ').

Here, when the open value of the outdoor electromagnetic expansion valve 65 of the main outdoor unit A1 is large, the low-temperature low-pressure gas refrigerant flows into the intake pipe 64 of the main outdoor unit A1, and then goes to the accumulator 52. Before the delivery, the refrigerant may flow out to the low pressure gas pipe 75, and the refrigerant delivered to the low pressure gas pipe 75 may be transferred to the sub outdoor unit through the low pressure gas pipe 75 ′ connected to the sub outdoor unit side. May be delivered to A2).

Therefore, in order to maintain a constant discharge temperature of the compressor, it is necessary to prevent the leakage of the refrigerant from the main outdoor unit A1 to the sub outdoor unit A2, and thus the first and second flow control valves 90 and 90 '. 2, the electromagnetic expansion valve and the first and second open / close valves 91 and 91 'should be controlled. Here, the first and second open / close valves 91 and 91 'are always closed to control the first and second electromagnetic expansion valves 90 and 90'.

Specifically, when the open value of the outdoor electromagnetic expansion valve 65 of the main outdoor unit A1 is large and the open value of the outdoor electromagnetic expansion valve 65 'of the sub outdoor unit A2 is small, the main outdoor unit ( Since the amount of the refrigerant flowing out of the sub outdoor unit A2 from A1) increases, control is performed to decrease the opening value of the second flow control valve 90 'of the sub outdoor unit A2.

On the contrary, when the open value of the outdoor electromagnetic expansion valve 65 of the main outdoor unit A1 is small and the open value of the outdoor electromagnetic expansion valve 65 'of the sub outdoor unit A2 is large, the sub outdoor unit A2. Since the amount of the refrigerant flowing out from the main outdoor unit (A1) increases in the ()), the control to reduce the opening value of the first flow control valve 90 of the main outdoor unit (A1).

That is, the opening value of the first flow control valve 90 is increased or decreased in accordance with the increase or decrease in the opening value of the outdoor electromagnetic expansion valve 65 of the main outdoor unit A1, and the The control is performed to increase or decrease the opening value of the second flow control valve 90 'according to the increase or decrease of the opening value of the outdoor electromagnetic expansion valve 65. Specifically, the first and second electromagnetic expansion valves 90 and 90 'are opened and closed at the same opening value as that of the outdoor electromagnetic expansion valves 65 and 65' of the main outdoor unit A1 and the sub outdoor unit A2. Can be.

3 shows the operation of the simultaneous heating and cooling simultaneous multi air conditioner 100 and the flow of the refrigerant according to the heating subject. For convenience of explanation, it is assumed that the first, second, and third rooms B1, B2, and B3 operate in a heating mode, and the fourth room B4 operates in a cooling mode. The flow of the refrigerant for operating the first, second, and third indoor rooms B1, B2, and B3 in the heating mode is the same as the flow of the refrigerant in all the heating room operations. However, after the high-pressure liquid refrigerant flows into the fourth chamber B4 from the liquid header 83 through the fourth interior connection pipe 43, the fourth chamber B4 expands in the fourth interior electromagnetic expansion valve 42 and the fourth chamber heat exchanger. After evaporation in the group 41, it is introduced into the low pressure gas header 82. Thereafter, the refrigerant flows through the low pressure gas pipes 75 and 75 ', enters the suction pipes 64 and 64', and mixes with the refrigerant evaporated in the outdoor heat exchangers 51 and 51 '.

In the simultaneous operation of the heating subjects, since the refrigerant flows into the outdoor units A1 and A2 through the low pressure gas pipes 75 and 75 ', the first and second flow control valves 90 and 90'. ) And the first and second open / close valves 91 and 91 'are controlled in a manner different from that in the heating room operation.

Specifically, when the ratio of the capacity of the indoor units B4 to be cooled and operated is equal to or greater than a set value, the first and second electromagnetic expansion valves 90 and 90 'and the first and second on / off valves 91 and 91'. Opens. When the ratio of the capacity of the indoor units B4 to be cooled and operated is greater than or equal to the set value, since the flow rate of the refrigerant flowing into the outdoor unit through the low pressure gas pipes 75 and 75 'is large, the outdoor units A1 and A2 are separated. This is because the refrigerant distribution can be controlled only by the outdoor electromagnetic expansion valves 65 and 65 'as in the prior art. Therefore, the first and second solenoid expansion valves 90 and 90 'and the first and second open / close valves 91 and 91' may be completely opened.

However, when the ratio of the capacity of the indoor units B4 to be cooled is less than the set value, the first and second on-off valves 91 and 91 'are closed and the first and second electromagnetic expansion valves 90 and 90 are closed. ') Is opened by a predetermined opening value to distribute the refrigerant between the main outdoor unit A1 and the sub outdoor unit A2.

At this time, if the ratio of the capacity of the indoor units (B4) to be cooled operation is less than the set value from the indoor unit (B4) to be cooled operation to the outdoor units (A1, A2) through the low pressure gas pipe (75, 75 '). Since the flow rate of the refrigerant flowing in is small, there is a case where the refrigerant distribution in the outdoor period is not effective.

 That is, if there is much refrigerant transferred to the suction pipe 64 'of the sub outdoor unit A2 through the low pressure gas pipe 75' due to the strong compressive force of the compressors 53 'and 54' of the sub outdoor unit, the main Even the refrigerant to be delivered to the suction pipe 64 of the outdoor unit A2 may be transferred to the suction pipe 64 'of the sub outdoor unit A2. This phenomenon is the same even when a large amount of refrigerant is delivered to the suction pipe 64 of the main outdoor unit A1 due to the strong compression force of the main compressors 53 and 54 of the main outdoor unit A1.

Therefore, when the ratio of the capacity of the indoor units B4 to be cooled as described above is less than the set value, the first and second open / close valves 91 and 91 'are closed and the first and second electromagnetic expansion valves 90 90 ') to distribute the refrigerant between the main outdoor unit A1 and the sub outdoor unit A2.

Specifically, the refrigerant delivered to the suction pipe 64 'of the sub outdoor unit A2 through the low pressure gas pipe 75' due to the strong compression force of the compressors 53 'and 54' of the sub outdoor unit A2. In many cases, the opening value of the second electromagnetic expansion valve 90 'is decreased and the opening value of the first electromagnetic expansion valve 90 is increased. Similarly, when there is a lot of refrigerant delivered to the suction pipe 64 of the main outdoor unit A1 due to the compressive force of the compressors 53 and 54 of the main outdoor unit A1, the first electromagnetic expansion valve 90 The opening value is decreased, and the opening value of the second electromagnetic expansion valve 90 'is increased.

Figure 4 shows the operation of the air-conditioning simultaneous multi-air conditioner 100 and the flow of the refrigerant according to the air conditioning room operation.

Referring to the main outdoor unit A1, the refrigerant of the high pressure gas discharged from the first and second compressors 53 and 54 flows through the first and second discharge pipes 55 and 56 and then to the third discharge. It flows into the outdoor heat exchanger 51 via the piping 68 and the four-way valve 62. The high pressure liquid refrigerant condensed in the outdoor heat exchanger 51 flows into the liquid header 83 through the subcooler 66. The refrigerant discharged from the liquid header 83 through the first, second, third, and fourth indoor connection pipes 13, 23, 33, and 43 may include the first, second, third, and fourth indoor expansion valves. 12) after being expanded in 22, 32, 42, and evaporated in the first, second, third and fourth indoor heat exchangers 11, 21, 31, 41, low pressure gas header 82 Flows into. The low pressure gas refrigerant discharged from the low pressure gas header 82 flows into the suction pipe 64 and is then sucked into the first and second compressors 53 and 54 through the accumulator 52.

Figure 5 shows the operation of the air-conditioning simultaneous multi-air conditioner 100 and the flow of the refrigerant according to the simultaneous operation of the cooling main subject. For convenience of explanation, it is assumed that the first, second, and third rooms B1, B2, and B3 operate in the cooling mode, and the fourth room B4 operates in the heating mode. The flow of the refrigerant for operating the first, second, and third rooms B1, B2, and B3 in the cooling mode is the same as the flow of the refrigerant in the air conditioner room operation. Hereinafter, description will be focused on the matters different from those in FIG. 4.

Referring to the main outdoor unit A1, a portion of the high pressure gas refrigerant discharged from the first and second compressors 53 and 54 flows through the lamination section 57 and flows through the high pressure gas pipe 63. It flows into the gas header 81. The refrigerant flowing out of the high pressure gas header 81 flows through the indoor connection pipe 44 of the fourth chamber, and then condenses in the fourth chamber heat exchanger 41 and flows into the liquid header 83. In the liquid header 83, both the refrigerant passing through the fourth chamber B4 and the refrigerant passing through the outdoor heat exchanger 51 in order to flow out into the first, second, and third chambers B1, B2, and B3. Mouth.

As described above, in the simultaneous operation of the cooling chamber or the cooling main body, the refrigerant is transferred to the suction pipes 64 and 64 'through the low pressure gas pipes 75 and 75' and the outdoor electromagnetic expansion valve 65. Since the refrigerant is not distributed between the outdoor units A1 and A2 under the control of .65 ', the first and second flow regulating valves 90 and 90' and the first and second opening and closing valves 91,91 ') need not be tightly controlled. Thus, the first and second flow control valves 90 and 90 'and the first and second open / close valves 91 and 91' are completely opened.

Simultaneous air-conditioning type multi air conditioner of the present invention has an advantage that can effectively distribute the refrigerant between the outdoor unit by installing a flow control valve on the low-pressure gas pipe connected to the outdoor unit.

In addition, since the flow rate of the refrigerant between the outdoor units can be controlled by adjusting the increase or decrease of the opening value of the flow control valve according to the increase or decrease of the opening value of the outdoor electromagnetic expansion valve during the heating all rooms, the compressor discharge temperature of the plurality of outdoor units. This has the advantage of keeping it constant.

In addition, during the operation of the heating main body, while the refrigerant is introduced from the indoor units and transferred to the main outdoor unit or the sub outdoor unit, the flow control valve and the shutoff valve may be adjusted so that even the refrigerant to be introduced into the other outdoor unit does not flow into the specific outdoor unit. Therefore, the compressor discharge temperature of the main outdoor unit and the sub outdoor unit can be kept constant.

Claims (11)

A plurality of compressors; In the multi-type air conditioner provided between the indoor heat exchanger and the outdoor heat exchanger and composed of a plurality of outdoor units having an outdoor electromagnetic expansion valve for controlling the flow rate of the refrigerant, A low pressure gas pipe connecting the suction parts of the plurality of compressors; In the heating all rooms operation or heating subjects simultaneously operation, simultaneous air-conditioning and multi-air including a flow rate control unit installed on the low-pressure gas pipe to control the flow rate of the refrigerant so that the flow rate of the refrigerant between the plurality of outdoor units is constantly adjusted Harmonizer. The method according to claim 1, The flow rate control unit is a cooling and heating simultaneous type which is a first flow control valve installed on a low pressure gas pipe connected to a main outdoor unit among the plurality of outdoor units, and a second flow control valve installed on a low pressure gas pipe connected to a sub outdoor unit among the plurality of outdoor units. Multi air conditioner. The method according to claim 2, The first and second flow control valves are first and second electronic expansion valves, respectively, and the first and second bypass pipes for bypassing the refrigerant flowing into the first and second flow control valves on the low pressure gas pipe; And a first and second on / off valves installed on the first and second bypass pipes. The method according to claim 3, Is disposed between the plurality of outdoor units and the indoor unit, and distributes the refrigerant to the air-conditioning combined indoor units according to the cooling and discharge chamber, the heating chamber, the cooling main body simultaneously and the heating main body simultaneously operating conditions, and includes a liquid header, low pressure gas header Air-conditioning simultaneous multi air conditioner further comprising a distributor. The method according to claim 4, The distributor may further include a high-pressure gas header through which a refrigerant having a higher pressure than the refrigerant in the low-pressure gas header may flow. The method according to claim 5, When the heating room is in operation, the first and second open / close valves are closed, and the opening value of the first flow control valve is increased or decreased according to the increase or decrease of the opening value of the first electromagnetic expansion valve, and the second An air conditioning simultaneous air conditioner multi-air conditioner in which the opening value of the second flow control valve increases or decreases as the opening value of the electromagnetic expansion valve increases or decreases. The method of claim 6, The air-conditioning simultaneous type air conditioner of the main outdoor unit having the same value as the opening degree of the electromagnetic expansion valve and the first electromagnetic expansion valve, and the opening degree of the electromagnetic expansion valve and the second electromagnetic expansion valve of the sub outdoor unit. The method of claim 5, The simultaneous heating and heating of the multi-air conditioner of the heating main body, when the ratio of the capacity of the indoor units to be cooled operation is more than the set value, the first, second electromagnetic expansion valve and the first, second opening and closing valve is opened. The method of claim 5, In the simultaneous operation of the heating subjects, when the ratio of the capacity of the indoor units to be cooled is less than the set value, the first and second open / close valves are closed, and the first outdoor unit is opened by a predetermined opening value to open the main outdoor unit. Air-conditioning simultaneous multi air conditioner for distributing refrigerant between the outdoor unit and the sub outdoor unit. The method of claim 5, The air-conditioning and simultaneous air conditioner of the first and second on / off valves and the first and second electromagnetic expansion valves are opened during the cooling chamber or the cooling main body operation. The method according to any one of claims 6 to 10, The first and second open / close valves are solenoid valves.

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