KR101230690B1 - Outdoor unit system for Multi-type air conditioner - Google Patents

Abstract

The present invention relates to an outdoor unit system of a multi-type air conditioner in which an oil recovery pipe for recovering oil and a hot gas pipe provided with a hot gas valve are installed side by side on one side of a compressor. The present invention provides an air conditioner capable of connecting a plurality of indoor units (200) to at least one outdoor unit (100), wherein the outdoor unit (100) comprises: an outdoor heat exchanger (180) in which heat exchange occurs; A plurality of compressors (120, 120 ') provided at one side of the outdoor heat exchanger (180) for compressing a refrigerant; A plurality of oil separators 122 provided at one side of the compressors 120 and 120 'to separate oil contained in the refrigerant discharged from the compressors 120 and 120'; It is provided on one side of the oil separator (122), and comprises a plurality of hot gas valve (125 ') that is opened and closed in accordance with the pressure of the refrigerant discharged from the compressor (120, 120'); The hot gas valve 125 ′ is installed in a hot gas pipe 125 formed side by side on an oil return pipe 123 where oil is recovered to the compressors 120 and 120 ′, and the hot gas valve 125 ′ is provided. It is characterized in that the solenoid valve is opened when the pressure of the compressor (120,120 ') is low and shielded when the pressure is high. According to such a configuration, the oil recovery of the compressor is easy, there is an advantage that the performance of the air conditioner is improved.

Air Conditioner, Outdoor Unit, Oil Recovery Pipe, Hot Gas Valve, Pressure Switch, Parallel

Description

Outdoor unit system for multi-type air conditioner {Outdoor unit system for Multi-type air conditioner}

1 is a state diagram of the conventional multi-type air conditioner.

Figure 2 is a block diagram showing the configuration of the conventional multi-type air conditioner and the refrigerant flow.

3 is a partial detailed configuration diagram of a conventional multi-type air conditioner outdoor unit.

Figure 4 is a state diagram of the multi-type air conditioner employing a preferred embodiment of the present invention.

5 is a block diagram of a multi-type air conditioner employing a preferred embodiment of the present invention.

Figure 6 is a detailed configuration diagram showing the outdoor unit configuration of a multi-type air conditioner employing a preferred embodiment of the present invention.

7 is a partial detailed configuration showing the outdoor unit configuration of a multi-type air conditioner employing a preferred embodiment of the present invention.

8 is a schematic flowchart illustrating an operation state of a hot gas valve according to a pressure of a compressor in an outdoor unit system of an air conditioner according to the present invention.

Explanation of symbols on the main parts of the drawings

100. Outdoor unit 102. Outdoor solenoid valve

120. Constant speed compressor 120 '. Inverter Compressor

120a. Refrigerant sprayer 120b, 120'b. Compressor Discharge Temperature Sensor

120c, 120'c. Pressure switch 121. Strain oil pipe

121 '. Strainer Oil Temperature Sensor 122. Oil Separator

122 '. Check valve 123. Oil return pipe

123a. Capillary 124. Four-way valve

124 '. High pressure sensor 125. Hot gas pipe

125 '. Hot gas valve 130. Supercooler

130 '. Station Convoy 130'a. Subcooling Expansion Valve

130'b. Super Cooling Inlet Sensor 130'c. Super Cooling Outlet Sensor

130a. Liquid line temperature sensor 131. Dryer

132. Accumulator 132 '. Suction Piping Temperature Sensor

132 ". Low pressure sensor 180. Outdoor heat exchanger

180 '. Tube assembly 180a. Heat exchanger temperature sensor

180b. Outdoor temperature sensor 182. Front heat exchanger

184. Rear heat exchanger 200. Indoor unit

202. Indoor heat exchanger 204. Expansion valve

210. Common fluid line 210 '. Basin

210 ". Outdoor liquid pipe 212. Common pipe

212 '. Branches 212 ". Outdoor

214. High and low pressure common pipe

The present invention relates to an air conditioner, and more particularly, an oil recovery pipe for recovering oil contained in a refrigerant, and a multi-type air conditioner installed side by side with a hot gas pipe having a hot gas valve opened and closed according to the pressure of the compressor. The outdoor unit system of the machine.

In general, an air conditioner is a cooling / heating system that cools a room by a repetitive action of inhaling hot air in a room, exchanging heat with a low temperature refrigerant, and then discharging it into the room. Condenser-Expansion Valve-Evaporator is a device that forms a series of cycles.

In addition, in recent years, there are various additions such as air purifying function that sucks and contaminates indoor contaminated air in addition to heating and cooling, and then makes it into clean air and reinjects it into the room, and dehumidifying function makes the humid air into wet and dry air and reinjects it into the room. It also serves as a functional.

Meanwhile, as is well known, air conditioners can be broadly classified into a separate type air conditioner in which the outdoor unit and the indoor unit are separately installed, and an integrated air conditioner in which the outdoor unit and the indoor unit are integrally installed.

In addition, recently, a multi-type air conditioner has been released that can be effectively applied when installing two or more air conditioners in a home or when installing an air conditioner in each office in a building having several offices. This multi-type air conditioner is connected to a plurality of indoor units in one outdoor unit, it is possible to obtain the same effect as installing a plurality of separate air conditioner.

1 is a schematic view showing an installation state of a conventional multi-type air conditioner, and FIG. 2 is a block diagram showing a configuration of a conventional multi-type air conditioner and a flow of a refrigerant. Referring to this, the outdoor unit 1 includes a compressor 10, an accumulator 20, an outdoor heat exchanger 30, and the like, and the indoor unit 50 includes an indoor heat exchanger 60 and an expansion valve 70.

In addition, in the multi-type air conditioner, a plurality of indoor units 50 are connected to one outdoor unit 1, and a high pressure pipe 80 having a high pressure and a relatively low pressure are connected between the outdoor unit 1 and the indoor unit 50. The low pressure pipe 90 of pressure is respectively connected.

When the air conditioner of the configuration described above performs the cooling action, the outdoor heat exchanger 30 of the outdoor unit 1 serves as a condenser to condense the refrigerant of the high temperature and high pressure gas state conveyed from the compressor (10). The refrigerant condensed as described above is expanded to a low-temperature / low-pressure gas while passing through the expansion valve 70 and is sent to the indoor heat exchanger 60.

The refrigerant introduced into the indoor heat exchanger 60 is converted into a two-phase refrigerant in which a gaseous state and a liquid state of low temperature and low pressure are mixed as heat is exchanged with indoor air. The refrigerant is passed through the accumulator 20 and then sent back to the compressor 10 to form one cycle of the refrigerant.

Next, when the air conditioner performs the heating operation, the flow of the refrigerant and the action of the heat exchanger are reversed. That is, the refrigerant compressed by the compressor 10 flows in the order of the accumulator 20-> indoor heat exchanger 60-> expansion valve 70-> outdoor heat exchanger 30.

At this time, the indoor heat exchanger 60 serves as a condenser for heat exchange between the high temperature and high pressure refrigerant passing through the inside and the indoor air, and the outdoor heat exchanger 30 heat exchanges the low temperature low pressure refrigerant and the outdoor air therein. It acts as an evaporator.

3 shows a detailed configuration of a conventional outdoor unit 1. As shown, the outdoor unit 1 is provided with an outdoor heat exchanger (30). The outdoor heat exchanger (30) is provided in pairs on the left and right to allow heat exchange between the refrigerant flowing inside and the outside air.

The compressor 10 is installed at one side of the outdoor heat exchanger 30. The compressor 10 is to compress the refrigerant to be a high temperature and high pressure, respectively provided on the left and right sides. That is, a constant speed compressor 10 'for constant speed operation is installed on the right side, and an inverter compressor 10 "is installed on the left side.

 An accumulator 20 is installed between the constant speed compressor 10 'and the inverter compressor 10 ". The accumulator 20 filters the liquid refrigerant so that only the refrigerant in the gas state flows into the compressor 10.

One side of the compressor 10 is provided with an oil separator 12, respectively. The oil separator 12 filters the oil mixed in the refrigerant discharged from the compressor 10 to be recovered to the compressor 10.

The oil separator 12 is connected to the compressor 10 by an oil return pipe 14. In addition, a capillary tube 14 ′ is formed in the oil return pipe 14 to allow oil separated from the oil separator 12 to be uniformly recovered to the compressor 10.

The four-way valve 16 is installed above the oil separator 12. The four-way valve 16 is in communication with the oil separator 12 by a pipe to change the flow direction of the refrigerant in accordance with the cooling and heating operation, each port is an outlet (or Oil separator), the inlet (or accumulator) of the compressor 10, the outdoor heat exchanger 30 and the indoor unit 50.

On the other hand, a hot gas pipe (18) across the four-way valve 16 to allow a portion of the refrigerant flowing into the four-way valve 16 from the oil separator 12 directly into the accumulator 20 Is installed.

When the hot gas pipe 18 needs to increase the pressure of the low pressure refrigerant flowing into the accumulator 20 during operation of the air conditioner, the high pressure refrigerant at the discharge port side of the compressor 10 is directly directed to the inlet side of the compressor 10. In order to be supplied, the hot gas pipe 18 is provided with a hot gas valve 18a which is a bypass valve to open and close the pipe.

However, the outdoor unit of the air conditioner according to the prior art as described above has the following problems.

That is, the oil separated from the oil separator 12 is always constantly supplied to the compressor 10 through the capillary tube 14 '. Therefore, when the oil of the compressor 10 is insufficient, there is a problem in that sufficient oil cannot be supplied.

In the cycle of the air conditioner as described above, the hot gas pipe 18 and the oil recovery pipe 14 are separated from each other, so that the structure is complicated and the hot gas pipe 18 and the oil recovery pipe 14 are separated. Since the pipes to be connected are relatively larger than the hot gas pipe 18 and the oil recovery pipe 14, there are more parts for processing the hot gas pipe 18 and the oil recovery pipe 14, which are relatively smaller pipes, and thus the pipe cracks caused by vibrations. There are also problems that are vulnerable to cracks.

An object of the present invention for solving the above problems, an oil recovery pipe for recovering oil contained in the refrigerant and a hot gas pipe is installed side by side on the compressor side of the hot gas valve is opened and closed according to the pressure of the compressor. It is to provide an outdoor unit system of the harmony unit.

The outdoor unit system of the multi-type air conditioner according to the present invention for achieving the above object, the air conditioner which can be connected to a plurality of indoor units to one or more outdoor units, the outdoor unit is an outdoor heat exchanger that heat exchange occurs; A plurality of compressors provided at one side of the outdoor heat exchanger to compress the refrigerant; A plurality of oil separators provided at one side of the compressor to separate oil contained in the refrigerant discharged from the compressor; It is provided on one side of the oil separator, characterized in that it comprises a plurality of hot gas valve opening and closing according to the pressure of the refrigerant discharged from the compressor.

One side of the oil separator is characterized in that the oil return pipe is formed to be connected to recover the oil to the compressor.

The hot gas valve is characterized in that installed in the hot gas pipe formed side by side on the oil return pipe.

The oil return pipe is characterized in that the capillary tube is further formed so that the oil is constantly recovered by the compressor.

The hot gas valve may be a solenoid valve that is opened when the pressure of the compressor is low and shielded when the pressure is high.

According to the present invention having such a configuration, the oil recovery of the compressor is easy, there is an advantage that the performance of the air conditioner is improved.

4 is a schematic view showing an installation state of the multi-type air conditioner according to the present invention, and FIG. 5 is a block diagram of the multi-type air conditioner according to the present invention. As illustrated, the outdoor unit 100 includes a constant speed compressor 120, an inverter compressor 120 ′, an accumulator 132, and an outdoor heat exchanger 180 and an outdoor solenoid valve 102 (LEV: linear expansion valve, hereinafter “outdoor LEV”). And the indoor unit 200 includes an indoor heat exchanger 202, an expansion valve 204, and the like.

In the multi-type air conditioner, a plurality of indoor units 200 are connected to one or more outdoor units 100. The common liquid pipe 210, which is a single pipe through which liquid refrigerant flows, is connected between the outdoor unit 100 and the indoor unit 200, The common engine 212, which is a single pipe through which gas refrigerant flows, is formed in communication. And, between the two or more outdoor unit 100 is installed in communication with the high and low pressure common pipe 214 to maintain the balance of the refrigerant.

The high and low pressure common pipe 214 is installed such that the inlet side of the outdoor heat exchanger 180 provided in the plurality of outdoor units 100 communicates with each other so that the balance of the refrigerant is maintained between the outdoor units 100. On the other hand, the refrigerant is also introduced into the outdoor heat exchanger 180 of the outdoor unit 100, which is not used among the plurality of outdoor units 100, thereby bringing the effect of improving the heat exchange efficiency as a whole. In addition, the high or low pressure common pipe 214 is a high-pressure or low-pressure refrigerant flows in accordance with the cooling or heating action.

The indoor unit 200 is formed with a branch liquid pipe 210 'through which liquid refrigerant flows, and a branch engine 212' through which gas refrigerant flows, and such a branch liquid pipe 210 'and a branch engine 212' are common. It is in communication with the liquid pipe 210 and the common engine 212.

The plurality of branch liquid pipes 210 'and the branch pipes 212' have different diameters according to the capacity of the connected indoor units 200.

An outdoor liquid pipe 210 "through which a liquid refrigerant flows and an outdoor pipe 212" through which a gas refrigerant flows are formed in the outdoor unit 100. The outdoor liquid pipe 210 "and the outdoor pipe 212" And communicates with the common liquid pipe 210 and the common engine 212.

6 and 7 show the outdoor unit system configuration of the air conditioner according to the present invention. As shown in these figures, the outdoor unit 100 is provided with an outdoor heat exchanger 180. The outdoor heat exchanger 180 is provided in pairs on the left and right to heat exchange between the refrigerant flowing through the outside and the outside air.

Compressors 120 and 120 'are installed at one side of the outdoor heat exchanger 30. The compressors 120 and 120 'are configured to compress the refrigerant to be high temperature and high pressure, and are provided at left and right sides, respectively. That is, a relatively constant speed compressor 120 for constant speed operation is installed on the right side, and an inverter compressor 120 'that is a variable speed heat pump is installed on the left side.

A refrigerant injector 120a is installed at the inlet side of the compressors 120 and 120 '. The refrigerant injector 120a prevents the compressor from being burned by supplying a refrigerant when the compressors 120 and 120 'are overheated according to operating conditions. The refrigerant used in the refrigerant injection unit 120a is discharged from the outdoor heat exchanger 180. It is preferred that the refrigerant be configured to be used.

A constant oil compressor 121 is installed between the constant speed compressor 120 and the inverter compressor 120 'such that the constant speed compressor 120 and the inverter compressor 120' communicate with each other. Accordingly, if a shortage of oil supply occurs in one of the compressors, it is replenished from other compressors to prevent the compressors 120 and 120 'from being burned out due to insufficient flow.

As the compressors 120 and 120 ', a scroll compressor having low noise and high efficiency is used. In particular, the inverter compressor 120' is an inverter scroll compressor in which the rotation speed is controlled according to the load capacity. Therefore, when a small number of indoor units 200 are used and the load capacity is small, the inverter compressor 120 'is first operated, and the constant speed is only achieved when the load capacity is gradually increased and cannot be handled only by the inverter compressor 120'. The compressor 120 is operated.

At the outlet side of the constant speed compressor 120 and the inverter compressor 120 ', the compressor discharge temperature sensors 120b and 120'b measure the temperature of the refrigerant discharged from the compressors 120 and 120' and the pressure of the refrigerant discharged is detected. Pressure switches 120c and 120'c and oil separator 122 are provided, respectively. The oil separator 122 filters the oil mixed in the refrigerant discharged from the compressors 120 and 120 'to be recovered to the compressors 120 and 120'.

That is, the oil used to cool the frictional heat generated when the compressors 120 and 120 'are driven is discharged to the outlet of the compressors 120 and 120' together with the refrigerant, and the oil in the refrigerant is separated into the oil separator 122. ) To return to the compressor (120, 120 ') through the oil return pipe (123).

The oil return pipe 123 is provided with a capillary tube 123a for allowing oil separated from the oil separator 120 to be uniformly recovered to the compressors 120 and 120 '.

A hot gas pipe 125 for bypassing the capillary pipe 123a is connected to the oil return pipe 123. That is, one end of the hot gas pipe 125 is connected to the inlet side of the capillary tube 123a, and the other end of the hot gas pipe 125 is connected to the outlet side of the capillary tube 123a. Some of the refrigerant of the oil separator 120 may be introduced into the compressors 120 and 120 'via the hot gas pipe 125.

When the hot gas pipe 125 needs to increase the pressure of the low pressure refrigerant flowing into the accumulator 132 or the compressors 120 and 120 'during the operation of the air conditioner, the high pressure refrigerant at the discharge port side of the compressors 120 and 120' is supplied to the compressor ( 120, 120 ') to be supplied directly to the inlet side, such a hot gas pipe 125 is provided with a hot gas valve 125' which is a bypass valve to open and close the pipe.

In addition, a check valve 122 ′ is further installed at an outlet side of the oil separator 122 to prevent a backflow of the refrigerant. That is, when only one of the constant speed compressor 120 or the inverter compressor 120 'is operated, the compressed refrigerant is not flowed back into the compressor 120 and 120' that are stopped.

The oil separator 122 is configured to communicate with the four-way valve 124 by the pipe. The four-way valve 124 is arranged to change the flow direction of the refrigerant according to the cooling and heating operation, each port is an outlet (or oil separator) of the compressor (120, 120 '), the inlet of the compressor (120, 120') Or an accumulator), an outdoor heat exchanger 180, and an indoor unit 200.

Therefore, the refrigerant discharged from the constant speed compressor 120 and the inverter compressor 120 ′ is collected into one place and then flows into the four-way valve 124. The compressors 120 and 120 are provided at the inlet of the four-way valve 124. A high pressure sensor 124 'for checking the pressure of the refrigerant discharged from') is installed.

On one side of the accumulator 132 is formed a supercooler (130). The supercooler 130 is a subcooling means for further cooling the refrigerant heat-exchanged in the outdoor heat exchanger 180, and is located at an arbitrary position of the outdoor liquid pipe 210 ″ connected to the outlet side of the outdoor heat exchanger 180. Is formed.

The supercooler 130 is formed of a double tube. That is, the outdoor liquid pipe 210 "is provided on the inner side, and the reverse conveying pipe 130 'is formed on the outer side. Therefore, the reverse conveying pipe 130' is branched from the outlet of the subcooler 130, The reverse transfer pipe 130 'is provided with a supercooled expansion valve 130'a for cooling the refrigerant by expansion.

In this case, a part of the refrigerant discharged from the subcooler 130 is introduced into the reverse transfer pipe 130 'and cooled while passing through the subcooling expansion valve 130'a, and the cooled refrigerant is the subcooler ( While refluxing 130, the inner refrigerant is further cooled. The countercurrent refrigerant exiting the subcooler 130 is supplied to the accumulator 132 and circulated again.

On the other hand, a liquid pipe temperature sensor 130a for measuring the temperature of the refrigerant discharged from the outdoor unit 100 is installed at the outlet of the subcooler 130, and a subcooling inlet sensor (at the outlet of the subcooling expansion valve 130'a). 130'b) is provided to measure the temperature of the reflux refrigerant flowing into the subcooler 130, and the subcooling outlet sensor 130 'in the reverse transfer pipe 130' flowing the reflux refrigerant discharged from the subcooler 130 c) is provided.

Therefore, the refrigerant passing through the outdoor heat exchanger 180 flows through the center portion and is configured such that the low temperature refrigerant expanded by an expansion valve (not shown) flows in the opposite direction to lower the temperature of the refrigerant. .

A dryer 131 is provided at one side of the supercooler 130, that is, at one side of the outdoor liquid pipe 210 ″ in which the refrigerant discharged from the outdoor heat exchanger 180 is guided to the indoor unit 200. 131 serves to remove moisture contained in the refrigerant flowing through the outdoor liquid pipe 210 ".

An accumulator 132 is installed between the constant speed compressor 120 and the inverter compressor 120 ′. The accumulator 132 filters the liquid refrigerant so that only the gaseous refrigerant flows into the compressors 120 and 120 '.

That is, when the refrigerant remaining in the liquid phase is not directly evaporated into gas among the refrigerant flowing from the indoor unit 200 directly flows into the compressors 120 and 120 ', the compressor 120 and 120' forms the refrigerant as a high temperature and high pressure gaseous refrigerant. ), The load is increased, which causes damage to the compressors 120 and 120 '.

Therefore, since the refrigerant remaining in the liquid state without being vaporized in the refrigerant flowing into the accumulator 132 is relatively heavy compared to the gaseous refrigerant, it is stored in the lower portion of the accumulator 132, and only the upper gaseous refrigerant is discharged to the compressor 120, 120 '). On the other hand, the inlet side of the accumulator 132 is provided with a suction pipe temperature sensor 132 ′ for measuring the temperature of the refrigerant sucked and a low pressure sensor 132 ″ for checking the pressure of the refrigerant.

Meanwhile, the outdoor heat exchanger 180 includes a front heat exchanger 182 and a rear heat exchanger 184, and each side of the outdoor heat exchanger 180 has refrigerant supplied from the compressors 120 and 120 ′. A tube assembly 180 'is formed that dispenses into portions. In addition, a heat exchanger temperature sensor 180a for measuring the temperature of the heat exchanger is installed inside the outdoor heat exchanger 180, and an outdoor temperature sensor 180b for measuring the external temperature is further provided on the outside.

Hereinafter, the operation of the multi-type air conditioner according to the present invention having the configuration as described above will be described.

As described above, in the air conditioner according to the present invention, a plurality of indoor units 200 are connected to one outdoor unit 100, and some or all indoor units 200 are operated according to a user's selection.

When the air conditioner is operated (cooling operation), the outdoor LEV 102 is opened so that the refrigerant flows between the outdoor unit 100 and the indoor unit 200.

First, referring to the refrigerant flow in the outdoor unit 100, the gas refrigerant flowing from the indoor unit 200 passes through the four-way valve 124 and then enters the accumulator 132. The gas refrigerant leaving the accumulator 132 is introduced into the compressors 120 and 120 '.

Meanwhile, when the refrigerant supplied to the compressors 120 and 120 'is insufficient or the compressors 120 and 120' are overheated, the refrigerant is supplied from the refrigerant injector 120a.

The refrigerant compressed by the compressors 120 and 120 ′ is discharged to the discharge port and passes through the oil separator 122. In the oil separator 122, oil contained in the refrigerant is separated and recovered to the compressors 120 and 120 ′ through the oil recovery pipe 123.

That is, as the refrigerant is compressed in the compressors 120 and 120 ', oil is mixed in the refrigerant. Since the oil is in the liquid state and the refrigerant is in the gas state, the oil is separated from the oil separator 122 which is the gas-liquid separator.

8 is a flowchart schematically illustrating an operation state of a hot gas valve according to a pressure of a compressor in an outdoor unit system of an air conditioner according to the present invention. As shown in the drawing, the pressure switches 120c and 120'c detect the pressure of the refrigerant discharged from the compressors 120 and 120 '(S300).

In response to the detection of the pressure switches 120c and 120'c, a controller (not shown) checks the pressure of the compressors 120 and 120 'to determine whether the pressure is high (S310). In this case, when the pressure of the compressors 120 and 120 'is high, the hot gas valve 125' is shielded (S320) to prevent the high temperature and high pressure refrigerant from flowing into the hot gas pipe 125 to the compressors 120 and 120 '. And only the oil (Oil) to the oil recovery pipe 123 is to be recovered to the compressor (120,120 ').

When the pressure of the compressors 120 and 120 'is low, the hot gas valve 125' is opened (S330) so that the high temperature and high pressure refrigerant flows into the hot gas pipe 125 into the compressors 120 and 120 '. At the same time, the oil separated from the oil separator 122 is introduced into the compressors 120 and 120 'by the oil recovery pipe 123 to allow the refrigerant of high temperature and high pressure to flow (S340).

On the other hand, the oil inside the compressor (120, 120 ') on both sides by the constant flow compressor 120 and the funnel oil pipe 121 is connected to the inverter compressor (120') to maintain a balance.

The refrigerant passing through the oil separator 122 flows into the outdoor heat exchanger 180 through the four-way valve 124. Since the outdoor heat exchanger 180 functions as a condenser (in the cooling mode), the refrigerant is cooled through heat exchange with external air to become a liquid refrigerant. The refrigerant passing through the outdoor heat exchanger 180 is further cooled while passing through the subcooler 130.

The refrigerant passing through the supercooler 130 passes through a dryer 131 for removing moisture contained in the refrigerant, and then flows into the indoor unit 200 through the common liquid pipe 210. Meanwhile, some of the refrigerant passing through the compressors 120 and 120 'may be introduced into the other outdoor unit 100 through the high and low pressure common pipe 214.

The refrigerant supplied to the other outdoor unit 100 through the high and low pressure common pipe 214 is introduced into the outdoor heat exchanger 180 of the outdoor unit 100 that is stopped to balance the refrigerant pressure as a whole, and the outdoor unit that is stopped ( The predetermined heat exchange also occurs through the outdoor heat exchanger 180 of 100).

When the refrigerant is supplied to the indoor unit 200 through the common liquid pipe 210, the refrigerant is supplied to each indoor unit 200 in operation through the branch liquid pipe 210 ′ branched from the common liquid pipe 210. The refrigerant is decompressed in the expansion valve 204 and heat exchanges in the indoor heat exchanger 202. At this time, since the indoor heat exchanger 202 serves as an evaporator, the refrigerant becomes low pressure gas through heat exchange.

The refrigerant discharged from the indoor heat exchanger 202 is collected through the branch engine 212 ′ to the common engine 212 and then flows into the outdoor unit 100. The refrigerant introduced into the outdoor unit 100 through the common engine 212 and the outdoor engine 212 ″ enters the accumulator 132 through the four-way valve 124.

In the accumulator 132, the liquid refrigerant that has not been evaporated is filtered out, and only the refrigerant in the gaseous state is selected and supplied to the compressors 120 and 120 '. Through this process, one cycle is completed.

On the other hand, when it is operated by the heating operation, the refrigerant flows in the opposite direction to the above, and the amount of refrigerant is controlled in the outdoor LEV (102).

Next, looking at the air flow in the outdoor unit 100, although not shown, the fan motor is driven in accordance with the application of power to drive the blower fan. When the blowing fan is rotated, outside air flows into the outdoor unit 100.

Air introduced into the outdoor unit 100 undergoes heat exchange while passing through the outdoor heat exchanger 180. At this time, when the air conditioner acts as cooling, the outside air receives heat from the outdoor heat exchanger 180 and becomes high temperature air. Becomes

The air passing through the outdoor heat exchanger 180 is forcedly blown upward by the blowing fan, and a shroud (not shown) guides the discharge of air upward.

The scope of the present invention is not limited to the above-described embodiments, and many other modifications based on the present invention will be possible to those skilled in the art within the scope of the present invention.

As described in detail above, in the outdoor unit system of the multi-type air conditioner according to the present invention, an oil recovery pipe for recovering oil contained in the refrigerant passing through the compressor and a hot gas valve opened and closed according to the pressure of the refrigerant discharged from the compressor are provided. The installed hot gas pipes were configured to be installed side by side on one side of the compressor.

Therefore, by installing the structure in which the oil recovery pipe and the hot gas pipe are separated in parallel in the conventional air conditioner, the structure can be simplified and the role of the conventional hot gas valve can be maintained as it is. An improved effect is expected.

In addition, by opening the hot gas valve when the oil is excessively discharged from the compressor, it is also expected that the role that can recover the oil is insufficient to recover only by the capillary tube.

In addition, the reduction of the pipe contact portion of the oil return pipe and hot gas valve is expected to reduce the potential failure to the pipe crack.

Claims (5)

In an air conditioner that can connect a plurality of indoor units to one or more outdoor units, The outdoor unit, An outdoor heat exchanger in which heat exchange takes place; A plurality of compressors provided at one side of the outdoor heat exchanger to compress the refrigerant; A plurality of oil separators provided at the discharge port side of the compressor to separate oil contained in the refrigerant discharged from the compressor; An oil recovery tube connecting one side of the oil separator and one side of the compressor to recover oil to the compressor, and having a capillary tube; A hot gas pipe connected to an oil recovery pipe so as to bypass the capillary pipe so that a portion of the refrigerant of the oil separator can be introduced into the compressor; And And a plurality of hot gas valves provided in the hot gas pipe and opened and closed according to the pressure of the refrigerant discharged from the compressor. delete delete The outdoor unit system of claim 1, wherein the oil return pipe further includes a capillary tube for uniformly recovering oil to the compressor. The outdoor unit system of claim 1, wherein the hot gas valve is a solenoid valve that is opened when the pressure of the compressor is low and is shielded when the pressure is high.

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