KR20080036314A - A reduction method of mode changeover noise for multi-airconditioner - Google Patents

Abstract

A method for reducing mode conversion noise of a multi-type air conditioner is provided to mount refrigerant bypass elements in a distributor for bypassing staying refrigerant and flowing refrigerant in the case of mode conversion, thereby reducing impulse and noise in the collision between the refrigerant under different pressures. A method for reducing mode conversion noise of a multi-type air conditioner includes a mode conversion step of converting operation mode between cooling mode and heating mode, a refrigerant stopping step of turning off both main and auxiliary valves(330a-330d,332a-332d), which are opened alternatively according to the cooling or heating mode to guide refrigerant from a distributor(300) to an outdoor unit(100) or indoor units(200), for stopping refrigerant flow, a refrigerant bypassing step of operating refrigerant bypass elements mounted in the distributor for bypassing the refrigerant stopped flowing but staying in branch pipes(340a-340d) before the mode conversion and the refrigerant flowing through the auxiliary valves after the mode conversion to avoid collision therebetween, and a bypass stopping step of stopping the operation of the refrigerant bypass elements not to bypass but to supply refrigerant to the indoor units, wherein the refrigerant bypass elements have refrigerant bypass pipes(372a-372d) and refrigerant bypass valves(374a-374d).

Description

A reduction method of mode changeover noise for multi-airconditioner

1 is a schematic configuration diagram of a conventional multi-type air conditioner.

Figure 2 is a block diagram showing the internal configuration of a distributor which is one component of a conventional multi-type air conditioner.

3 is a schematic diagram of a multi-type air conditioner according to the present invention;

Figure 4 is a block diagram showing the configuration of the multi-type air conditioner employed in accordance with the present invention.

Figure 5a is a perspective view showing the external configuration of a distributor which is one configuration of the multi-type air conditioner according to the present invention.

Figure 5b is a perspective view showing the internal configuration of the distributor which is one configuration of the multi-type air conditioner according to the present invention.

Figure 6 is a block diagram of a distributor which is one component of a multi-type air conditioner according to the present invention.

Figure 7a is a multi-type air conditioner according to the present invention showing the operation of the refrigerant flow in the cooling room operation.

Figure 7b is a diagram showing the operation of the refrigerant flow of the multi-type air conditioner in the process of switching from the cooling chamber operation to the cooling main operation in accordance with the present invention.

Figure 8a is a configuration diagram showing the refrigerant flow in the multi-type air conditioner according to the present invention the operation of the cooling main body.

Figure 8b is a configuration diagram showing the refrigerant flow of the multi-type air conditioner according to the invention the process of switching from the cooling main operation to the heating room operation.

Figure 9a is a multi-type air conditioner according to the present invention showing the operation of the refrigerant flow during the heating room operation.

Figure 9b is an operation configuration showing the refrigerant flow of the multi-type air conditioner according to the present invention the process of switching from the heating room operation to the heating main operation.

Figure 10a is a configuration diagram showing the refrigerant flow when the multi-type air conditioner according to the present invention the heating main operation.

Figure 10b is an operation configuration showing a state in which the refrigerant flow is stopped by the refrigerant bypass means when the multi-type air conditioner according to the present invention is switched from the heating main operation to the cooling discharge chamber operation.

10c is an operation configuration showing a state in which the refrigerant flow is bypassed by the refrigerant bypass means when the multi-type air conditioner according to the present invention is switched from the heating main operation to the cooling discharge chamber operation.

11 is a flow chart showing a switching noise reduction method of a multi-type 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

121. Bacteria oil pipe 122. Oil separator

124. Four-way valve 130. Outdoor supercooler

130'.Reverse transfer pipe 130'a.Supercooled expansion valve

131.Dryer 132. Accumulator

180. Outdoor heat exchanger 182'.vertical

182 ". Tilt 198. Cooling piping

198 '. Cooling valve 200. Indoor unit

202. Indoor heat exchanger 204. Expansion valve

210. Liquid pipe 210 '. Chamber

210 ". Indoor connecting fluid pipe 212. Low pressure pipe

212 '. Indoor engine 212 ". Indoor engine

214. High pressure engine 300. Splitter

310. Splitter case 315. Splitter cover

320. Liquid connector 322. High pressure connector

324. Low pressure connection pipe 330. Main valve

332. Auxiliary valves 340. Branch pipes

350. Simultaneous supercooler 352. Bypass tube

354. Supercooling control valve 360. Condensate removal means

370. Refrigerant bypass means 372. Refrigerant bypass tube

374. Refrigerant bypass valve S100. Mode switching step

S200. Refrigerant stop step S300. Refrigerant Flow Stage

S400. Refrigerant bypass step S500. Bypass Blocking Step

The present invention relates to a method of reducing switching noise of a multi-type air conditioner, and more particularly, includes a bypass means inside a distributor for connecting an outdoor unit to an indoor unit, and when the cooling / heating switching is carried out, The present invention relates to a method of reducing switching noise of a multi-type air conditioner to bypass pressure so as to bypass the collision.

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 which forms a series of cycles.

Recently, in addition to heating and cooling, there are various additional functions such as the air purifying function that inhales and filters contaminated air in the room and makes it into clean air and reinjects it into the room, and the dehumidification function of making humid air into wet and dry air again. It also functions.

Recently, multi-type air conditioners have been released that can be effectively applied when two or more air conditioners are installed in a home or when an air conditioner is installed in each office in a building having several offices. Such a multi-type air conditioner is connected to a plurality of indoor units in one outdoor unit, and the same effect as installing a plurality of separate air conditioners can be obtained.

1 schematically shows an installation state of a multi-type air conditioner according to the prior art.

As shown, the multi-type air conditioner is provided with at least one or more outdoor units 10, a plurality of indoor units 20 and a distributor 30 installed between the outdoor unit 10 and the indoor unit 20 to control the flow of the refrigerant, and the like. It consists of.

The outdoor unit 10 is generally installed outdoors of a building, and an internal unit 10 includes a compressor (not shown), an accumulator (not shown), and an outdoor heat exchanger (not shown) for compressing a refrigerant, which is a working fluid, at high temperature and high pressure. It is provided.

And the indoor unit 20 is generally installed in the interior of the building to discharge the air directly into the space for air conditioning, although not shown is provided with an indoor heat exchanger, expansion valves and the like inside.

Between the outdoor unit 10 and the distributor 30, a liquid pipe 12 which is a single pipe through which liquid refrigerant flows, a high pressure engine 14 through which a high pressure gas refrigerant flows, and a low pressure engine 16 through which a low pressure gas refrigerant flows are communicated. It is installed.

The indoor unit 20 includes an indoor liquid pipe 22 through which liquid refrigerant flows, and an indoor engine 24 through which gas refrigerant flows, and the indoor liquid pipe 22 and the indoor engine 24 are connected to the liquid pipe 12. It is installed to communicate with the high pressure engine (14) and low pressure engine (16).

In addition, the indoor units 20 as described above may be installed differently in their types and characteristics, and the detailed description thereof will be omitted since the internal configuration is substantially the same.

On the other hand, the distributor 30 is also called a H Recovery Unit (Heat Recovery Unit), as shown in Figure 2 the lower portion of the distributor 30, the liquid pipe 12, the high pressure pipe 14, the low pressure pipe 16 The liquid connection pipe 32, high pressure connection pipe 34, the low pressure connection pipe 36, respectively fastened to the) is formed to protrude.

In addition, the outer surface of the distributor 30 is formed such that the indoor connection pipe 42 and the indoor connection liquid pipe 44 which are fastened to the indoor engine 24 and the indoor liquid pipe 22 are protruded, respectively. Therefore, the indoor connection pipe 42 is fastened to the indoor engine 24, and the indoor connection pipe 44 is fastened to the indoor liquid pipe 22 to guide the flow of the refrigerant.

The indoor connection engine 42 is provided with a plurality of main valve 46 and auxiliary valve 48 consisting of a bypass valve. That is, as shown, a first main valve 46a is installed in the first indoor connection engine 42a fastened to the first indoor engine 24a, and a second indoor connection fastened to the second indoor engine 24b. The second main valve 46b is installed in the engine 42b. A third main valve 46c is installed in the third indoor connection engine 42c fastened to the third indoor engine 24c, and the fourth indoor connection engine 42d connected to the fourth indoor engine 24d. The fourth main valve 46d is installed to selectively pass the refrigerant.

Meanwhile, the indoor connection engine 42 is branched inside the distributor 30 to form a branch pipe 50. That is, the first branch pipe 50a is branched from the first indoor connection pipe 42a, and the first branch pipe 50a is provided with a first auxiliary valve 48a to provide the first branch pipe 50a. The refrigerant passing through is selectively controlled.

The second branch connection pipe 42b, the third indoor connection pipe 42c, and the fourth indoor connection pipe 42d also have a second branch pipe 50b, a third branch pipe 50c, and a fourth branch pipe, respectively. 50d is branched, and each of these branch pipes 50 also has a second subsidiary valve 48b, a third subsidiary valve 48c, and a fourth subsidiary valve 48 having the same function as the first subsidiary valve 48a. 48d) are provided respectively.

The branch pipe 50 is in communication with the high pressure connecting pipe (48). That is, each branch pipe 50 has one end connected to the indoor connection engine 42, and the other end connected to the high pressure connection pipe 34, respectively. Accordingly, when the auxiliary valve 48 is opened, the indoor engine 24 and the high pressure engine 14 communicate with each other.

The distributor 300 is further provided with a simultaneous supercooler 54. The simultaneous supercooler 54 is operated when the air conditioner is simultaneously heated and cooled to serve to improve the cooling efficiency. The simultaneous supercooler 54 is connected to the liquid pipe 12, it is composed of a double pipe to further cool the refrigerant flowing through the liquid pipe 12.

A bypass pipe 56 branched from the liquid pipe 12 is further formed at the inlet of the simultaneous supercooler 54, and the bypass pipe 56 is provided with a supercooling control valve 58. The supercooling control valve 58 is opened during the simultaneous operation of air conditioning and cooling to allow the refrigerant flowing through the liquid pipe 12 to be further cooled. That is, the two-phase (gas + liquid) refrigerant flowing through the liquid pipe 12 is cooled in the co-supercooler 54 to be converted into a complete liquid phase.

Condensate removal means 60 is further provided inside the distributor 30. The condensate removing means (60) is a refrigerant connecting pipe (62) for allowing the high pressure engine (14) and the low pressure engine (16) to communicate with each other, and a connecting pipe for controlling the flow of the refrigerant through the refrigerant connecting pipe (62). It has a configuration that includes an on-off valve 64 and a capillary tube 66 for expanding the refrigerant flowing through the refrigerant connection pipe 62.

The connecting pipe opening and closing valve 64 opens the refrigerant connecting pipe 62 when the air conditioner is operated in the cooling chamber operation mode, and the refrigerant flowing through the refrigerant connecting pipe 62 is the capillary tube 66. Inflates. Therefore, during the operation of the cooling chamber, the condensate of the refrigerant condensed in the high pressure engine 14 expands and is recovered to the low pressure engine 16.

However, the multi-type air conditioner according to the prior art configured as described above has the following problems.

That is, when the air conditioner is switched from cooling (heating) to warming (cooling), only one of the main valves 46 and the auxiliary valves 48 is selectively opened. In this case, the indoor connection engine 42 The refrigerant inside the flow direction is changed to each other, the high pressure refrigerant and the low pressure refrigerant collide with each other.

Therefore, a large noise is generated due to collision between the high-pressure refrigerant and the low-pressure refrigerant, there is a problem that causes emotional discomfort.

In addition, when the high-pressure refrigerant and the low-pressure refrigerant collides with the vibration in the indoor connection engine 42, the vibration is transmitted not only to the indoor connection engine 42, but also to the indoor engine 24 and the branch pipe (50) It is undesirable because it will cause breakage.

Accordingly, an object of the present invention is to provide a multi-type air conditioner having a bypass means inside a distributor connecting an outdoor unit and an indoor unit, and bypassing the high pressure refrigerant and the low pressure refrigerant so as not to collide with each other during the cooling / heating switching. It relates to a switching noise reduction method of the group.

Switching noise reduction method of the multi-type air conditioner according to the present invention for achieving the above object, the mode switching step of switching the operation mode of the air conditioner from cooling (heating) to egg (cooling), and A refrigerant stop step of selectively opening according to the cooling or heating operation mode of the air conditioner to stop the refrigerant flow by turning off both the main valve and the auxiliary valve for guiding the refrigerant inside the distributor to the outdoor unit or the indoor unit; A refrigerant flow step of guiding the refrigerant flow by turning on any one of the auxiliary valves, and by operating a refrigerant bypass means provided in the distributor, the refrigerant stopped before the air conditioner is switched to cooling / heating. A refrigerant bypassing step of bypassing the refrigerants flowing after the switching so as not to collide with each other, and a bypass to stop the refrigerant bypassing means by stopping the refrigerant bypassing means It characterized by configured by comprising a single phase.

The refrigerant stopping step is characterized in that the process of stopping the flow of the refrigerant through the refrigerant bypass means by shielding the refrigerant bypass valve for selectively limiting the refrigerant flow in the refrigerant bypass means.

The refrigerant bypassing step is characterized in that the refrigerant is bypassed through the refrigerant bypass tube by opening the refrigerant bypass tube, one end is in communication with the low pressure connection pipe and the other end is in communication with the indoor connection engine.

 The coolant flow step and the coolant bypass step are performed at the same time.

The coolant flow step and the coolant bypass step are performed for 2 to 3 minutes.

According to the multi-type air conditioner according to the present invention having such a configuration, it is possible to simultaneously cool and heat a single air conditioner system, and to easily install a plurality of indoor units and outdoor units.

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

3 is a schematic block diagram of a multi-type air conditioner employing a preferred embodiment of the present invention, Figure 4 is a block diagram showing a configuration of a multi-type air conditioner employing a preferred embodiment of the present invention have.

As shown, the multi-type air conditioner is provided with at least one or more outdoor units 100, a plurality of indoor units 200, and a distributor 300 installed between the outdoor units 100 and the indoor units 200 to control the flow of the refrigerant. It consists of.

The outdoor unit 100 is generally installed outdoors of a building, and includes a constant speed compressor 120 and a variable speed heat pump inverter compressor 120 ', an accumulator 132, and outdoor heat exchange. Group 180 and an outdoor solenoid valve 102 (LEV: linear expansion valve, hereinafter referred to as 'outdoor LEV').

And the indoor unit 200 is generally installed in the interior of the building to discharge the air directly to the space for air conditioning, the interior heat exchanger 202, expansion valve 204 and the like are provided respectively.

Between the outdoor unit 100 and the distributor 300, the liquid pipe 210 which is a single pipe through which liquid refrigerant flows, the high pressure engine 214 through which the high pressure gas refrigerant flows, and the low pressure engine 212 through which the low pressure gas refrigerant flows are in communication. It is installed.

The indoor unit 200 includes an indoor liquid pipe 210 'through which liquid refrigerant flows, and an indoor engine 212' through which gas refrigerant flows, and the indoor liquid pipe 210 'and the indoor engine 212' are respectively connected to the liquid pipe. 210 is installed to communicate with the high pressure engine 214 and the low pressure engine (212).

In addition, the plurality of indoor units 200 as described above may be installed in different types and characteristics, and accordingly, the indoor liquid pipe 210 'and the indoor engine 212' may be installed according to the capacity of the indoor unit 200 connected thereto. The diameters are different from each other.

That is, the indoor unit 200 includes a first indoor unit 200a, a second indoor unit 200b, a third indoor unit 200c, and a fourth indoor unit 200d. Each indoor unit 200 includes a first indoor unit. 212'a, 2nd indoor engine 212'b, 3rd indoor engine 212'c, 4th indoor engine 212'd, 1st indoor liquid pipe 210'a, 2nd indoor The liquid pipe 210'b, the third indoor liquid pipe 210'c, and the fourth indoor liquid pipe 210'd are connected to each other to guide the flow of the refrigerant, and each indoor unit 200 and the indoor liquid pipe 210 ' ) And the indoor engine 212 ′ may be configured differently in size and capacity.

Meanwhile, each expansion valve 204 provided in the indoor unit 200 controls the refrigerant flowing into each indoor heat exchanger 202. That is, the first indoor heat exchanger 202a and the first expansion valve 204a are provided in the first indoor chamber 200a, and the second indoor heat exchanger 202b and the second expansion valve are provided in the second indoor chamber 200b. 204b, a third indoor heat exchanger 202c and a third expansion valve 204c are provided in the third indoor chamber 200c, and a fourth indoor heat exchanger 202d in the fourth indoor chamber 200d. ) And a fourth expansion valve 204d. Therefore, each of the expansion valve 204 is controlled differently according to the user's selection, and adjusts the flow rate of the refrigerant flowing into the indoor heat exchanger (202).

On the other hand, a constant oil compressor 121 is installed between the constant speed compressor 120 and the inverter compressor 120 'to allow the constant speed compressor 120 and the inverter compressor 120' to communicate with each other. Therefore, when oil supply shortage occurs in one of the compressors, the compressor 120 is replenished from the other compressor to prevent burnout of the compressors 120 and 120 'due to the insufficient flow rate.

As the compressors 120 and 120 ', a low noise and excellent scroll compressor is used. In particular, the inverter compressor 120' is an inverter scroll compressor whose rotation speed is adjusted 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 operated first, and when the load capacity is gradually increased, the inverter compressor 120' can not afford the constant speed compressor ( 120 is activated.

At the outlet side of the constant speed compressor 120 and the inverter compressor 120 ', the compressor discharge temperature sensors 120b and 120'b and the oil separator 122 for measuring the refrigerant temperature discharged from the compressors 120 and 120' are respectively provided. . 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, oil used to cool frictional heat generated when the compressors 120 and 120 'are driven is discharged to the outlet of the compressors 120 and 120' together with a refrigerant. The oil in the refrigerant is separated into the oil separator 122. Is separated and sent back to the compressor (120,120 ').

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 120/120' that is stopped.

The oil separator 122 is configured to communicate with the four-way valve 124 by the pipe. The four-way valve 124 is disposed 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 (or the compressor 120, 120') Accumulator), outdoor heat exchanger 180 and the indoor unit 200 is connected.

Therefore, the refrigerant discharged from the constant speed compressor 120 and the inverter compressor 120 'is collected in one place and then flows into the four-way valve 124.

Meanwhile, the four-way valve has a hot gas pipe 125 that allows a part of the refrigerant flowing into the four-way valve 124 from the oil separator 122 to be directly introduced into the accumulator 132 which will be described below. 124 is installed across.

When the hot gas pipe 125 needs to increase the pressure of the low pressure refrigerant flowing into the accumulator 132 during the operation of the air conditioner, the high pressure refrigerant at the discharge port of the compressors 120 and 120 'is directly directed to the inlet side of the compressor 120 and 120'. To be supplied.

The outdoor supercooler 130 is provided at the outlet side of the outdoor heat exchanger 180. The outdoor supercooler 130 to further cool the refrigerant heat exchanged in the outdoor heat exchanger 180, is formed at any position of the liquid pipe (210).

The outdoor supercooler 130 is formed of a double pipe. That is, an inner tube (not shown) in communication with the liquid tube 210 is formed in the center, and an outer tube (not shown) in communication with the reverse transfer tube 130 ′, which will be described below, is formed on the outer side of the inner tube. .

On the other hand, in the liquid pipe 210 formed at the outlet of the outdoor supercooler 130, the reverse transfer pipe 130 'is formed in communication. The reverse transfer pipe 130 'serves to guide the refrigerant discharged from the outdoor heat exchanger 180 and flows through the liquid pipe 210 into the outer pipe (not shown) and flows back.

The reverse transfer pipe 130 ′ is provided with a supercooled expansion valve 130 ′ a that converts the liquid refrigerant into a low temperature gas refrigerant by expansion. The subcooled expansion valve 130 ′ may control the amount of refrigerant flowing back through the back transfer pipe 130 ′.

Therefore, the refrigerant passing through the outdoor supercooler 130 is a temperature desired by the user. That is, as the amount of refrigerant flowing back through the back transfer pipe 130 ′ increases, the temperature of the refrigerant passing through the outdoor supercooler 130 will be lowered.

When a part of the refrigerant discharged from the outdoor supercooler 130 is introduced into the reverse conveying pipe 130 'by the above configuration, the low temperature gas refrigerant is expanded while passing through the subcooling expansion valve 130'a. The low temperature gas refrigerant flows back through the outer tube (not shown) of the outdoor supercooler 130 to further cool the liquid refrigerant flowing through the inner tube (not shown) through heat exchange.

As such, the liquid refrigerant discharged from the outdoor heat exchanger 180 is further cooled by the heat conduction while passing through the outdoor supercooler 130, and is supplied to the indoor unit 200, and the outer tube of the outdoor supercooler 130 is provided. The reflux refrigerant discharged from (not shown) is supplied back to the compressors 120 and 120 'via the accumulator 132 and circulated.

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

An accumulator 132 is installed between a central portion of the base fan 110, that is, 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 without being evaporated into gas among the refrigerant flowing from the indoor unit 200 directly flows into the compressors 120 and 120 ', the load is increased on the compressors 120 and 120', resulting in damage. .

Therefore, among the refrigerants introduced into the accumulator 132, the refrigerant which is not evaporated and remains in the liquid phase is stored in the lower part of the accumulator 132 because it is relatively heavier than the refrigerant in the gas phase, and only the gaseous refrigerant in the upper portion of the compressor 120, 120 Flows into ').

The outdoor heat exchanger 180 is provided in the outdoor unit 100. The outdoor heat exchanger 180 is a vertical portion 182 ′ which is installed upright with respect to the ground to exchange heat between the refrigerant flowing inside and the outside air, and the right side from the lower end of the vertical portion 182 ′. It consists of an inclined portion 182 "formed to be inclined at a predetermined angle.

Meanwhile, FIG. 5A and FIG. 5B show a distributor that is one configuration of a multi-type air conditioner employing a preferred embodiment of the present invention, and FIG. 6 illustrates a distributor that is one configuration of a multi-type air conditioner employing a preferred embodiment of the present invention. A block diagram of is shown.

As shown therein, the dispenser 300 is also called a H Recovery Unit, and is provided in a rectangular distributor case 310 and an upper side of the distributor case 310 to shield the inside of the distributor cover. An appearance is formed by 315.

On both sides of the distributor case 310, the liquid pipe 210 and the high pressure pipe 214 and the low pressure pipe 212 is connected to the liquid connection pipe 320, the high pressure connection pipe 322 and the low pressure connection pipe 324 Each is formed to protrude. Accordingly, the liquid connecting pipe 320 is fastened to the liquid pipe 210, the high pressure connecting pipe 322 is connected to the high pressure pipe 214, and the low pressure connecting pipe 324 is fastened to the low pressure pipe 212, respectively. You will be guided.

Since the liquid connection tube 320, the high pressure connection tube 322, and the low pressure connection tube 324 are formed to protrude to both sides of the distributor case 310, when the plurality of outdoor units 100 are respectively installed on the left and right sides. Edo is connected to each of the liquid pipe 210, high pressure engine 214 and low pressure engine 212 is easy.

In addition, the front of the distributor case 310 is formed so that the indoor connection pipe 212 ″ and the indoor connection liquid pipe 210 ″ fastened to the indoor engine 212 ′ and the indoor liquid pipe 210 ′ respectively protrude forward. . Therefore, the indoor connection pipe 212 ″ is fastened to the indoor engine 212 ′, and the indoor connection pipe 210 ′ is fastened to the indoor liquid pipe 210 ′ to guide the flow of the refrigerant.

The indoor connection engine 212 ″ is provided with a plurality of main valves 330 and auxiliary valves 332 including bypass valves. That is, as illustrated, a first indoor engine 212 ′ of the first indoor chamber 200 is shown. A first main valve 330a is installed in the first indoor connection engine 212 "a fastened to a), and a second indoor connection fastened with the second indoor engine 212'b of the second indoor chamber 200b. The second main valve 330b is installed in the engine 212 "b.

In addition, a third main valve 330c is installed in the third indoor connection engine 212 ″ c which is engaged with the third indoor engine 212 ′ c of the third indoor chamber 200c, and the third indoor valve 200d of the fourth indoor chamber 200d. A fourth main valve 330d is installed in the fourth indoor connection engine 212 "d connected to the fourth indoor engine 212'd to selectively pass the refrigerant.

Therefore, when the air conditioner is operated in the cooling or heating mode, the main valves 330a, 330b, 330c, and 330d and the auxiliary valves 332a, 332b, 332c, and 332d are selectively opened, and the air conditioner is cooled / heated. At the time of switching, the main valves 330a, 330b, 330c, and 330d and the auxiliary valves 332a, 332b, 332c, and 332d are both shielded for a predetermined time, more precisely, 2 to 3 minutes.

This is to reduce the impact amount of the high pressure refrigerant and the low pressure refrigerant generated by changing the flow direction of the refrigerant generated when the cooling / heating operation mode is switched.

Meanwhile, the indoor connection engine 212 "is branched inside the distributor 300 to form a branch pipe 340. That is, a first branch pipe 340a is formed from the first indoor connection engine 212" a. The first branch pipe 340a is branched, and a first auxiliary valve 332a is installed to selectively control the refrigerant passing through the first branch pipe 340a.

A second branch pipe 340b and a third branch pipe 340c are also applied to the second indoor connection engine 212 "b, the third indoor connection engine 212" c, and the fourth indoor connection engine 212 "d, respectively. ) And the fourth branch pipe 340d, and each of the branch pipes 340 also has a second auxiliary valve 332b and a third auxiliary valve 332c having the same function as the first auxiliary valve 332a. And a fourth auxiliary valve 332d, respectively.

The branch pipe 340 is in communication with the high pressure connecting pipe 322. That is, each branch pipe 340 has one end connected to the indoor connection engine 212 ", and the other end connected to the high pressure engine 214. Therefore, when the auxiliary valve 332 is opened, The indoor engine 212 ′ and the high pressure engine 214 communicate with each other.

The distributor 300 is further provided with a simultaneous supercooler 350. The simultaneous supercooler 350 is operated when the air conditioner is simultaneously heated and cooled to serve to improve the cooling efficiency. The simultaneous supercooler 350 is connected to the liquid pipe 210, and is configured as a double pipe like the outdoor supercooler 130 to further cool the refrigerant flowing through the liquid pipe 210.

And although not shown, the liquid pipe 210 provided in the interior of the simultaneous supercooler 350 is preferably made of a spiral tube. The spiral tube improves the cooling rate and the cooling efficiency.

Meanwhile, as shown in FIG. 6, a bypass pipe 352 branched from the liquid pipe 210 is further formed at an inlet of the simultaneous supercooler 350, and the bypass pipe 352 is provided with a supercooling control valve 354. . The supercooling control valve 354 is opened during the simultaneous operation of air conditioning and heating to allow the refrigerant flowing through the liquid pipe 210 to be further cooled. That is, the two-phase (gas + liquid) refrigerant flowing through the liquid pipe 210 is cooled in the simultaneous supercooler 350 to be converted into a complete liquid phase.

The condenser liquid removing means 360 is further provided inside the distributor 300. The condensate removing unit 360 includes a refrigerant connection pipe 362 for allowing the high pressure engine 214 and the low pressure engine 212 to communicate with each other, and a connection pipe for controlling the flow of the refrigerant through the refrigerant connection pipe 362. An on / off valve 364 and a capillary tube 366 for expanding the refrigerant flowing through the refrigerant connecting pipe 362 are included.

The connection pipe open / close valve 364 opens the refrigerant connection pipe 362 when an air conditioner is operated in a cold discharge chamber operation mode, and the refrigerant flowing through the refrigerant connection pipe 362 is the capillary pipe 366. Inflates. Therefore, during the cooling chamber operation, the condensate of the refrigerant condensed in the high pressure engine 214 expands and is recovered to the low pressure engine 212.

Meanwhile, the refrigerant bypass means 370 is further provided inside the distributor 300. The refrigerant bypass means 370 serves to reduce the amount of impact by bypassing the refrigerant when the refrigerant stopped before the cooling / heating switching of the indoor unit 200 and the refrigerant flowing after the cooling / heating switching collide with each other. .

That is, the refrigerant bypass means 370 serves to reduce noise generated at the time of cooling / heating switching by bypassing the refrigerant when the high pressure refrigerant and the low pressure refrigerant collide with each other to correct the pressure difference between the refrigerants. To perform.

To this end, the refrigerant bypass means 370 is a refrigerant bypass pipe 372 is installed so that one end is in communication with the low-pressure connection pipe 324 and the other end is in communication with the indoor connection engine 212 ", and the refrigerant bypass pipe 372 It is configured to include a refrigerant bypass valve 374 for selectively opening and closing the inside of the.

In more detail, the refrigerant bypass pipes 372a, 372b, 372c, and 372d and the refrigerant bypass valves 374a, 374b, 374c, and 374d are formed in the first indoor connection engine 212 " a " One each in the fourth indoor connection engine 212 "d.

The refrigerant bypass valves 374a, 374b, 374c, and 374d are operated in the cooling and discharging chamber, and are opened and closed in the same manner as the auxiliary valves 332a, 332b, 332c, and 332d when any one chamber is opened in the heating mode. .

Therefore, the branch pipes 340a, 340b, 340c, and 340d in the state in which the auxiliary valves 332a, 332b, 332c, and 332d and the refrigerant bypass valves 374a, 374b, 374c, and 374d are shielded when operating in the cooling mode. The refrigerant remaining in the branch pipe 340a from the outdoor unit 100 is opened as the auxiliary valves 332a, 332b, 332c, and 332d and the refrigerant bypass valves 374a, 374b, 374c, and 374d open at the time of switching to the heating mode. Even though the coolant is introduced into the coolant introduced into the coolant 340b, 340c, and 340d, a part of the coolant bypass pipe 372a, 372b, 372c, and 372d is introduced into and bypassed, thereby reducing the impact.

Hereinafter, the operation and switching noise reduction method of the multi-type air conditioner according to the present invention having the configuration as described above will be described with reference to FIGS. 7A to 10C.

First, with reference to Figure 7a looks at the operating state during the operation of the cooling room. When the air conditioner is selected and switched to the cooling chamber operation by the user, the first chamber 200a, the second chamber 200b, the third chamber 200c and the fourth chamber 200d are all used for cooling. do.

Looking at the refrigerant flow in the outdoor unit 100, the gas refrigerant flowing from the indoor unit 200 is compressed and then discharged from the compressor (120, 120 '), the refrigerant discharged from the compressor (120, 120') is the oil separator Oil passes through 122 and is recovered to the compressors 120 and 120 '. 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.

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 discharged from the outdoor heat exchanger 180 passes through the cooling dedicated pipe 198 provided below the outdoor heat exchanger 180. That is, during the cooling chamber operation, since the cooling valve 198 ′ provided in the cooling dedicated pipe 198 is open, the refrigerant passing through the outdoor heat exchanger 180 passes through the outdoor LEV 102. Without passing through the cooling dedicated pipe (198).

In the cooling and discharging chamber operation, the subcooling expansion valve 130 ′ a is opened to operate the outdoor supercooler 130. Therefore, the refrigerant passing through the cooling only pipe 198 is further cooled in the outdoor and the cooler 130 becomes a liquid refrigerant. The refrigerant passing through the outdoor supercooler 130 passes through a dryer (131) for removing moisture contained in the refrigerant and then flows into the distributor (300) through the liquid pipe (210).

The distributor 300 distributes and supplies a refrigerant to the plurality of indoor units 200. That is, the first indoor chamber 200a through the first indoor liquid pipe 210'a, the second indoor liquid pipe 210'b, the third indoor liquid pipe 210'c and the fourth indoor liquid pipe 210'd, The refrigerant is supplied to the second indoor chamber 200b, the third indoor chamber 200c, and the fourth indoor chamber 200d, respectively.

The refrigerant introduced into each indoor unit 200 is expanded by the expansion valve 204 to be decompressed, and heat exchange is performed in each indoor heat exchanger 202. At this time, since the first indoor heat exchanger 202a, the second indoor heat exchanger 202b, the third indoor heat exchanger 202c, and the fourth indoor heat exchanger 202d all serve as evaporators, the refrigerant is exchanged through heat exchange. Low pressure gas.

The refrigerant discharged from the indoor heat exchanger 202 is introduced back into the distributor 300 via the respective indoor engines 212 ′. In this case, each of the auxiliary valve 332 and the refrigerant bypass valve 374 in the distributor 300 are in an off state and the main valve 330 is in an on state. The refrigerant passes through.

The refrigerant passing through the distributor 300 enters the accumulator 132 through the low pressure engine 212. 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, during the operation of the cold discharge chamber as described above, a part of the high pressure refrigerant discharged from the compressors 120 and 120 'is also partially moved to the high pressure engine 214. However, the flow of the refrigerant through the high pressure engine 214 is blocked in the distributor 300. That is, since the first auxiliary valve 332a, the second auxiliary valve 332b, the third auxiliary valve 332c and the fourth auxiliary valve 332d in the distributor 300 are turned off, the high pressure engine The refrigerant is condensed and accumulated in the 214 and the high-pressure connecting pipe 322.

In addition, since the connection pipe open / close valve 364 is opened during the operation of the cooling discharge chamber, the refrigerant flows through the refrigerant connection pipe 362. That is, the refrigerant inside the high pressure engine 214 moves to the low pressure engine 212 through the refrigerant connection pipe 362, and the condensed refrigerant is expanded by the capillary tube 366 and recovered to the low pressure engine 212. . As such, when the refrigerant flows through the refrigerant connection pipe 362, the air conditioner maintains a stable cycle as a whole.

Next, the refrigerant flow during the operation of the cooling main body will be described with reference to FIGS. 7B and 8A.

During the cooling main body operation after the cooling chamber operation, the first indoor chamber 200a, the second indoor chamber 200b, and the third indoor chamber 200c of the four indoor units 200 operate in the cooling mode, and the fourth indoor chamber ( Only 200d) is operated by heating.

To this end, the user switches the operation mode of the fourth indoor unit 200d from cooling to heating among the plurality of indoor units of the air conditioner. (Mode switching step: S100)

After the mode switching step S100 is performed in this way, as shown in FIG. 7B, the fourth main valve 330d, the fourth auxiliary valve 332d, and the fourth refrigerant bypass valve 374d are simultaneously turned off. In the fourth indoor chamber 200d, the refrigerant flow is stopped, and thus the refrigerant stopping step S200 is performed.

In the refrigerant stopping step (S200), the shielded state is maintained for 2 to 3 minutes while the fourth main valve 330d remains shielded as shown in FIG. 8A, and the fourth auxiliary valve 332d and the fourth refrigerant are blocked. The bypass valve 374d is opened.

That is, the refrigerant flow step (S300) for guiding the refrigerant flow by turning on the fourth auxiliary valve (332d), and by operating the refrigerant bypass means to open the fourth refrigerant bypass valve (374d) cold / The refrigerant bypass step (S400) for bypassing the refrigerant stopped before the heating switching and the refrigerant flowing after the cooling / heating switching does not collide with each other is performed at the same time.

Accordingly, the low pressure refrigerant stopped in the fourth branch pipe 340d, more specifically, the portion “A” of FIG. 7B, collides with the high pressure refrigerant flowing through the fourth auxiliary valve 332d, Refrigerants having different pressures are bypassed to the fourth coolant bypass pipe 372d so that the pressure difference is corrected so that the impact amount is reduced and the noise can be reduced.

When the high pressure refrigerant and the low pressure refrigerant are balanced by the refrigerant bypassing step (S400), the fourth auxiliary valve 332d is shielded to guide the refrigerant into the fourth chamber 200d without bypassing the fourth auxiliary valve 332d. (Bypass blocking step: S500)

When the bypass blocking step (S500) is completed, even if the air conditioner is switched from cooling to heating it is possible to reduce the noise due to the collision of the refrigerant.

In the outdoor unit 100, the refrigerant discharged from the compressors 120 and 120 ′ passes through the oil separator 122, and oil is separated and recovered to the compressors 120 and 120 ′.

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 discharged from the outdoor heat exchanger 180 passes through the outdoor LEV 102. At this time, the amount of refrigerant is controlled by the outdoor LEV 102, and the cooling exclusive pipe 198 is blocked by the cooling valve 198 ′. In addition, since the supercooled expansion valve 130 ′ is turned off, the refrigerant flows into the distributor 300 through the liquid pipe 210.

The refrigerant introduced into the distributor 300 is supercooled by the simultaneous supercooler 350. That is, since the subcooling control valve 354 is opened, a part of the refrigerant introduced through the liquid pipe 210 is introduced into the bypass pipe 352 and expanded. Therefore, the refrigerant flowing in the simultaneous supercooler 350 is further cooled.

The coolant further cooled while passing through the simultaneous supercooler 350 is the indoor connection engine 212 "a, 212" b, 212 "c and the first, second and third indoor liquid pipes 210'a, 210'b, 210. The first, second, and third indoor rooms 200a, 200b, and 200c are introduced via 'c).

At this time, since the auxiliary valves 332a, 332b, and 332c and the refrigerant bypass valves 374a, 374b, and 374c are shielded, the branch pipes 340a, 340b, and 340c and the refrigerant bypass tubes 372a, 372b, and 372c. The refrigerant flow is blocked.

The refrigerant flowing into the first, second, and third indoor chambers 200a, 200b, and 200c passes through the first, second, and third indoor heat exchangers 202a, 202b, and 202c to realize cooling through heat exchange with indoor air. Done. That is, since the first, second and third indoor heat exchangers 202a, 202b and 202c act as evaporators, the refrigerant becomes a low pressure gas through heat exchange.

The refrigerant passing through the first, second, and third indoor chambers 200a, 200b, and 200c is introduced into the distributor 300 again. At this time, the first, second and third main valves 330a, 330b and 330c of the distributor 300 are opened and the fourth main valve 330d is off. The first, second, and third auxiliary valves 332a, 332b, and 332c are turned off, and the fourth auxiliary valve 332d is turned on to open.

Therefore, the low pressure refrigerant introduced into the distributor 300 flows into the outdoor unit 100 through the low pressure engine 212 and enters the accumulator 132. 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.

In addition, during the operation of the cooling main body, a part of the high pressure refrigerant discharged from the compressors 120 and 120 'is also partially moved to the high pressure engine 214. This refrigerant is introduced into the distributor 300.

At this time, the first, second and third auxiliary valves 332a, 332b and 332c are all turned off in the distributor 300 and the fourth auxiliary valve 332d and the fourth refrigerant bypass valve 374d are described above. Only open.

Accordingly, some of the refrigerant stopped in the fourth branch pipe 340d is diverted to the fourth indoor connection engine 212 ″ d through the fourth refrigerant bypass pipe 372d, and the rest of the refrigerant is stopped in the fourth room. It is introduced into the fourth indoor chamber 200d through the engine 212'd.

At this time, since the fourth indoor heat exchanger 202d of the fourth indoor chamber 200d acts as a condenser, the refrigerant is changed into a liquid phase and flows into the distributor 300 through the fourth indoor liquid pipe 210'd. The liquid refrigerant flowing into the distributor 300 is mixed with the refrigerant flowing through the liquid pipe 210 and flows to the first, second, and third indoor chambers 200a, 200b, and 200c as described above, and used for cooling. do.

The reason why the liquid refrigerant of the distributor 300 does not flow back to the fourth indoor liquid pipe 210'd is due to the pressure difference of the refrigerant. That is, the pressure of the refrigerant in the fourth indoor liquid pipe 210'd is relatively larger than the pressure of the refrigerant in the first, second and third indoor liquid pipes 210'a, 210'b and 210'c.

Hereinafter, the operation state in the heating room operation will be described with reference to FIGS. 8B and 9A. First, the air conditioner is operated in the cooling main body operation mode, and the user switches the operation mode to the heating room operation. (Mode switching step: S100)

At this time, the first indoor (200a), the second indoor (200b), the third indoor (200c) and the fourth indoor (200d) are all used for heating. In addition, since the functions of the respective components have been described in the state description during the cooling and discharging chamber operation, detailed functions of the respective components will be omitted.

After the mode switching step (S100) in this way, as shown in Figure 8b, the first, second, third main valve (330a, 330b, 330c) and the first, second, third auxiliary valve (332a, 332b, 332c) ) And the first, second, and third refrigerant bypass valves 374a, 374b, and 374c are all turned off at the same time, and the refrigerant flow is stopped in the first, second, and third indoor chambers 200a, 200b, and 200c. S200) is performed. (4th indoor (200d) is still in heating operation mode)

In the refrigerant stopping step (S200), the shielded state is maintained for 2 to 3 minutes, and the first, second and third auxiliary valves 332a, 332b and 332c and the first, second and third refrigerant bypasses as shown in FIG. 9A. Valves 374a. 374b and 374c are open.

That is, the refrigerant flow step (S300) for guiding the refrigerant flow by turning on the first, second, third auxiliary valves (332a, 332b, 332c) and the refrigerant bypass means 370 to operate the first By opening the 2,3 refrigerant bypass valves (374a.374b, 374c), the refrigerant bypass step (S400) for bypassing the refrigerant which is stopped before the cooling / heating switching and the refrigerant flowing after the cooling / heating switching does not collide with each other simultaneously Will be implemented.

Accordingly, the low pressure refrigerant stopped in the first, second, and third branch pipes 340a, 340b340c, and more specifically, in the portion “B” of FIG. 8b, includes the first, second, and third auxiliary valves 332a, 332b, 332c is collided with a high-pressure refrigerant flowing through, and at this time, the refrigerant having a different pressure is bypassed to the first, second, and third refrigerant bypass pipes 372a, 372b, 372c, and the pressure difference is corrected. The amount of impact is reduced and eventually noise can be reduced.

When the high pressure refrigerant and the low pressure refrigerant achieve pressure equilibrium while passing through the refrigerant bypassing step (S400), the first, second and third refrigerant bypass valves 374a, 374b, and 374c are shielded to prevent the refrigerant from bypassing the first and second refrigerants. It is guided to flow into the room 2,3 (200a, 200b, 200c). (Bypass blocking step: S500)

When the bypass blocking step (S500) is completed, even if the air conditioner is switched from cooling to heating it is possible to reduce the noise due to the collision of the refrigerant.

Meanwhile, referring to the refrigerant flow in the outdoor unit 100, the refrigerant discharged from the compressors 120 and 120 ′ passes through the oil separator 122 and flows into the distributor 300 through the high pressure engine 214.

In the distributor 300, each main valve 330 is turned off, and each auxiliary valve 332 is turned on and opened. Therefore, the refrigerant introduced into the distributor 300 through the high pressure engine 214 flows into the indoor engine 212 ′ through the branch pipe 340.

At this time, the refrigerant passing through the branch pipe 340 is in a high pressure state, and the first, second, and third chambers 200a, 200b, and 200c are operated in a cooling state before being operated in the heating chamber. The low-pressure refrigerant is stopped inside the second and third branch pipes 340a, 340b, and 340c.

Accordingly, a pressure difference occurs when the high pressure refrigerant and the low pressure refrigerant collide with each other. As described above, the first, second and third refrigerant bypass valves 374a, 374b, and 374c are turned on and thus the first, second, Since the three refrigerant bypass tubes 372a, 372b and 372c are open, when the low pressure refrigerant and the high pressure refrigerant collide with each other, a part of the refrigerant passes through the first, second and third refrigerant bypass tubes 372a, 372b and 372c. The amount of impact is reduced by flowing into the engine 212.

The refrigerant introduced into the indoor engine 212 ′ through the branch pipe 340 is supplied to the indoor unit 200 and condensed through heat exchange with indoor air while passing through the indoor heat exchanger 202.

That is, in the case of heating, the indoor heat exchanger 202 acts as a condenser to warm the internal air by heat generation. Since the expansion valves 204 are all open, the refrigerant changed into a liquid phase while passing through the indoor heat exchanger 202 flows into the distributor 300 through the indoor liquid pipe 210 '.

The liquid refrigerant in the distributor 300 is introduced into the outdoor unit 100 through the liquid pipe 210. The refrigerant introduced into the outdoor unit 100 passes through the outdoor LEV 102 and is supplied to the outdoor heat exchanger 180 to generate heat exchange. At this time, since the outdoor heat exchanger 180 acts as an evaporator, the liquid refrigerant is changed to the gas phase by heat exchange with external air.

The low-pressure refrigerant in the gas phase discharged from the outdoor heat exchanger 180 passes through the four-way valve 104 and is supplied to the compressors 120 and 120 'through the accumulator 132. Through this process, one heating cycle is formed.

Hereinafter, with reference to Figures 9b and 10a looks at the operating state of the heating main operation. First, the air conditioner is operated in the heating room operation mode, and the user switches the operation mode to the heating subject operation. (Mode switching step: S100)

In this case, the first indoor room 200a, the second indoor room 200b, and the third indoor room 200c continue to operate in the heating mode, and only the fourth indoor room 200d is switched to cooling.

After the mode switching step S100 is performed, as shown in FIG. 9B, the fourth main valve 330d, the fourth auxiliary valve 332d, and the fourth coolant bypass valve 374d are simultaneously turned off. In the fourth indoor chamber 200d, the refrigerant flow is stopped, and thus the refrigerant stopping step S200 is performed.

In the refrigerant stopping step S200, the shielded state is maintained for 2 to 3 minutes, and the fourth auxiliary valve 332d and the fourth refrigerant bypass valve 374d are opened as shown in FIG. 10A.

That is, the fourth auxiliary valve 332d is turned on, and the refrigerant flow step S300 for guiding the refrigerant flow and the refrigerant bypass means 370 are operated to open the fourth refrigerant bypass valve 374d. By doing so, the refrigerant bypassing step (S400) of bypassing the refrigerant which is stopped before the cooling / heating switching and the refrigerant flowing after the cooling / heating switching does not collide with each other is simultaneously performed.

Therefore, the high-pressure refrigerant stopped in the fourth branch pipe 340d, more specifically, the "C" portion of FIG. 9B collides with the low-pressure refrigerant via the fourth indoor chamber 200d, where The refrigerant having a different pressure is bypassed to the fourth coolant bypass pipe 372d so that the pressure difference is corrected so that the impact amount is reduced and the noise can be reduced.

When the high pressure refrigerant and the low pressure refrigerant achieve a pressure balance while passing through the refrigerant bypassing step (S400), the fourth refrigerant bypass valve 374d is shielded to guide the refrigerant into the outdoor unit 100 without bypassing the refrigerant. (Bypass blocking step: S500)

When the bypass blocking step (S500) is completed, even if the air conditioner is switched from cooling to heating it is possible to reduce the noise due to the collision of the refrigerant.

In this state, the flow direction of the refrigerant is as shown in FIG. 10B.

Hereinafter, an operation state at the time of a cooling room operation will be described with reference to FIGS. 10B and 10C. First, the air conditioner is operated in the heating subject operation mode, and the user switches the operation mode to the cold discharge chamber operation. (Mode switching step: S100)

At this time, the first indoor (200a), the second indoor (200b), the third indoor (200c) and the fourth indoor (200d) are all used for cooling.

After the mode switching step S100 is performed, the first, second and third main valves 330a, 330b and 330c and the first, second and third auxiliary valves 332a, 332b and 332c as shown in FIG. 10B. And the first, second, third, and fourth refrigerant bypass valves 374a, 374b, 374c, and 374d are all turned off at the same time, and the refrigerant flow is stopped in the first, second, and third indoor chambers 200a, 200b, and 200c. The stop step (S200) is carried out. (4th indoor (200d) is still in the cooling operation mode)

In the refrigerant stopping step (S200), the shielded state is maintained for 2 to 3 minutes, and the first, second and third auxiliary valves 332a, 332b and 332c and the first, second and third refrigerant bypasses as shown in FIG. Valves 374a. 374b and 374c are open.

That is, the refrigerant flow step (S300) for guiding the refrigerant flow by turning on the first, second, third auxiliary valves (332a, 332b, 332c) and the refrigerant bypass means 370 to operate the first By opening the 2,3 refrigerant bypass valves (374a.374b, 374c), the refrigerant bypass step (S400) for bypassing the refrigerant which is stopped before the cooling / heating switching and the refrigerant flowing after the cooling / heating switching does not collide with each other simultaneously (See FIG. 10C).

Accordingly, the high-pressure refrigerant stopped inside the first, second, and third branch pipes 340a, 340b, and 340c, and more specifically, in the “C” portion of FIG. 10b, includes the first, second, and third room 200a, 200b. , And collides with the low-pressure refrigerant flowing through the 200c, and the refrigerant having different pressures bypasses the first, second, and third refrigerant bypass tubes 372a, 372b, and 372c to correct the pressure difference.整), the impact amount is reduced, and eventually the noise can be reduced.

When the high pressure refrigerant and the low pressure refrigerant are balanced to each other through the refrigerant bypassing step (S400), the refrigerant is not bypassed by shielding the first, second, and third refrigerant bypass valves 374a, 374b, and 374c (see FIG. 7A). It is guided to flow into the outdoor unit 100 without. (Bypass blocking step: S500)

When the bypass blocking step (S500) is completed, even if the air conditioner is switched from cooling to heating it is possible to reduce the noise due to the collision of the refrigerant.

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

As described above, in the switching noise reduction method of the multi-type air conditioner according to the present invention, the pressure difference is provided by providing a bypass means inside the distributor and bypassing the stop refrigerant and the flow refrigerant generated at the time of cooling / heating switching. It was configured to reduce the impact amount of the refrigerant having a.

Therefore, there is an advantage in that noise and impact generated due to a pressure difference when a high-pressure refrigerant and a high-temperature refrigerant collide with each other are reduced.

In addition, there is an advantage that the circulation of the refrigerant is smooth and the customer's emotional complaints are eliminated due to the above reason.

In addition, there is an advantage that the damage to the air conditioner is prevented in advance and the air conditioning efficiency is improved.

Claims (5)

A mode switching step of switching the operation mode of the air conditioner from the heating (cooling) room to the heating (cooling) room; Refrigerant stop step of selectively opening according to the cooling or heating operation mode of the air conditioner to stop the refrigerant flow by turning off both the main valve and the auxiliary valve for guiding the refrigerant inside the distributor to the outdoor unit or the indoor unit; A refrigerant flow step of guiding a refrigerant flow by turning on any one of the main valve and the auxiliary valve; A refrigerant bypass step of operating the refrigerant bypass means provided in the distributor to bypass the refrigerant stopped before the cooling / heating switching of the air conditioner and the refrigerant flowing after the switching do not collide with each other; And a bypass blocking step of stopping the refrigerant bypass means and blocking the refrigerant from being bypassed. The method of claim 1, wherein the refrigerant stop step, And shielding the refrigerant bypass valve for selectively limiting the refrigerant flow in the refrigerant bypass means to stop the flow of the refrigerant through the refrigerant bypass means. The method of claim 2, wherein the refrigerant bypass step, A method of reducing switching noise of a multi-type air conditioner, wherein a refrigerant is bypassed through a refrigerant bypass tube by opening a refrigerant bypass pipe having one end communicating with the low pressure connection pipe and the other end communicating with an indoor connection engine. 4. The method of claim 1, wherein the refrigerant flow step and the refrigerant bypass step are performed simultaneously. The method of claim 4, wherein the refrigerant flow step and the refrigerant bypass step are performed for 2 to 3 minutes.

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