KR20090089949A - Air conditioner - Google Patents

Abstract

An air conditioner is provided to perform initial operation of a compressor stably in case intake pressure of the compressor is low, and to drive the compressor with an optimized state. An air conditioner includes an outer unit(10), a 4-way valve(130), one or more indoor unit(21,22,23), a main bypass pipe(170), a bypass vale(172), a 3-way valve(173), a first sub-pipe(174) and a second sub-pipe(175). The outdoor unit includes a compressor(110) and an outdoor heat exchanger(160). The indoor unit includes an indoor heat exchanger(211,231). The 4-way valve adjusts a flow direction of a refrigerant discharged from the compressor. The main bypass pipe bypasses a part of the refrigerant. The bypass valve controls refrigerant flow. The 3-way valve is equipped in the main bypass pipe.

Description

Air Conditioner

This embodiment relates to an air conditioner.

In general, an air conditioner is a device for cooling or heating an internal space of a building or the like. Today, in order to more efficiently cool or heat an indoor space divided into a plurality of rooms, development of a multi air conditioner for cooling or heating each room is continuously made.

The air conditioner includes an outdoor unit provided with an outdoor heat exchanger and an indoor unit provided with an indoor heat exchanger. And, when the air conditioner operates in the cooling mode, the outdoor heat exchanger acts as a condenser, and the indoor heat exchanger acts as an evaporator. On the other hand, when the air conditioner operates in the heating mode, the outdoor heat exchanger acts as an evaporator and the indoor heat exchanger acts as a condenser.

An object of the present embodiment is to ensure that the compressor is discharged from the compressor to the suction side of the compressor when the compressor is started or when the suction pressure of the compressor is low, so that the initial startup of the compressor is stable, and the compressor can be optimally driven. Is to propose an air conditioner.

Another object of the present embodiment is to propose an air conditioner to adjust the amount of the refrigerant to be moved to the indoor unit according to the operation number of the plurality of indoor units.

In one aspect, an air conditioner includes an outdoor unit including a compressor and an outdoor heat exchanger; At least one indoor unit having an indoor heat exchanger; Four-way valve for adjusting the flow direction of the refrigerant discharged from the compressor; A main pipe configured to bypass a portion of the refrigerant discharged from the compressor; Bypass valve for controlling the flow of the refrigerant to the main pipe; A three-way valve provided in the main pipe; A first sub pipe connected to the three-way valve and the suction side of the compressor; And a second sub pipe connected to the three-way valve and the outdoor heat exchanger side pipe.

According to the proposed embodiment, the suction pressure of the compressor may increase as the refrigerant discharged from the compressor is bypassed to the suction side of the compressor when the compressor is initially started or when the suction pressure of the compressor is significantly low. Therefore, the difference between the suction pressure and the discharge pressure during initial startup of the compressor is small, so that the compressor can be stably started.

Further, according to the present embodiment, when some indoor units of the plurality of indoor units are heated and heated, part of the refrigerant discharged from the compressor is bypassed to the outdoor heat exchanger side. Therefore, as more refrigerant does not flow to the indoor unit than the capacity of the indoor unit to be operated, the amount of refrigerant corresponding to the capacity of the indoor unit to be operated flows to the indoor unit, there is an advantage that the refrigerant noise due to the excessive refrigerant flow is eliminated, The air conditioner can operate stably.

Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings.

1 is a refrigerant cycle configuration diagram of an air conditioner according to the present embodiment.

Referring to FIG. 1, the air conditioner according to the present embodiment includes at least one outdoor unit 10 and at least one indoor unit 20 connected to the outdoor unit 10.

In FIG. 1, one outdoor unit 10 and three indoor units (first, second, and third indoor units: 21, 22, and 23) are provided, but the number of the outdoor unit 10 and the indoor unit 20 is shown in FIG. 1. Note that there is no limit.

The outdoor unit 10 includes a compression unit 110, an outdoor heat exchanger 150, and a four-way valve 130 for switching a refrigerant flow direction according to a heating or cooling operation of the air conditioner.

Each indoor unit (21, 22, 23) has an indoor heat exchanger (211, 221, 231), an indoor expansion valve (LEV: 212, 222, 232) and the refrigerant flow to each indoor unit, respectively Refrigerant control valves (213, 223, 233) to control is included. One refrigerant control valve (213, 223, 233) is provided on each of the suction and discharge sides of each indoor unit (21, 22, 23).

In detail, the compression unit 110 includes an inverter compressor 112 for variable speed operation and a constant speed compressor 114 for constant speed operation.

Therefore, when a small number of indoor units are used and the load capacity is low, the inverter compressor 112 is first operated. When the load capacity gradually increases to exceed the capacity of the inverter compressor 112, the constant speed compressor 114 is used. Is activated.

An accumulator 120 is connected to the inlet side of the compressors 112 and 114 to allow gaseous refrigerant to flow into the compressors 112 and 114. On the discharge side of each of the compressors 112 and 114, oil separators 122 and 124 are provided for separating oil from refrigerant and oil discharged from the compressors 112 and 114. The oil separators 122, 124 are in communication with the suction side of the compressors 112, 114.

The compressors 112 and 114 are connected to four-way valves 130 for switching the flow direction of the refrigerant discharged from the compressors 112 and 114. The refrigerant discharged from the compressors 112 and 114 by the four-way valve 130 may be selectively moved to the outdoor heat exchanger 150 or the indoor heat exchanger 211 and 221.

In addition, the connection pipe 162 connecting the outdoor heat exchanger 150 and the indoor units 21 and 22 is provided with an outdoor electromagnetic expansion valve 160. In addition, a parallel pipe 164 is provided to allow the refrigerant to flow when the outdoor heat exchanger 150 acts as an evaporator in parallel with the connection pipe 162 at the boundary of the outdoor electronic expansion valve 160.

In addition, the parallel pipe 164 includes a check valve 166 for blocking the flow of the refrigerant when the outdoor heat exchanger 150 acts as an evaporator and allowing the refrigerant to pass through when acting as a condenser. .

One end of the main bypass pipe 170 is connected between the discharge side of the compressors 112 and 114 and the four-way valve 130. The three-way valve 173 is connected to the other end of the main bypass pipe 170. In addition, the main bypass pipe 170 is provided with a bypass valve 172 for adjusting the flow rate of the refrigerant.

The three-way valve 173 is connected to first and second sub bypass pipes 174 and 175 (hereinafter referred to as "sub pipes"). The first sub pipe 174 is connected between the four-way valve 130 and the accumulator 120. Therefore, the refrigerant flowing along the first sub pipe 174 is sucked into the compressors 112 and 114 after passing through the accumulator 120.

The second sub pipe 175 is connected between the outdoor heat exchanger 150 and the outdoor electromagnetic expansion valve (or check valve). Therefore, for example, during the heating operation of the air conditioner, the refrigerant flowing along the second sub pipe 175 is sucked into the outdoor heat exchanger 150.

The first sub pipe 174 is provided with a first capillary 176 to depressurize the refrigerant, and the second sub pipe 175 is provided with a second capillary 177. At this time, the diameter of the first capillary 176 is the second capillary 177 so that the refrigerant flow rate of the first sub pipe 174 is greater than the refrigerant flow rate of the second sub pipe 175. ) Or greater than the diameter of the first capillary 176 is greater than the length of the second capillary 177.

The diameter difference of each said capillary 176 and 177 is demonstrated.

In the case where the refrigerant flows through the first sub pipe 174, the difference between the suction pressure and the discharge pressure of the compressors 112 and 114 at the initial startup of the compressor is reduced. That is, by allowing the refrigerant discharged from the compressors 112 and 114 to bypass to the suction side of the compressors 112 and 114, the suction pressure of the compressors 112 and 114 is increased. As such, when the difference between the suction pressure and the discharge pressure becomes small during the initial startup of the compressor, the compressor can be stably started.

In the case where the refrigerant flows through the first sub pipe 174, the suction pressure of the compressor is remarkably low. In this case, the suction pressure of the compressors 112 and 114 may be increased by allowing the refrigerant discharged from the compressors 112 and 114 to bypass the suction side of the compressors 112 and 114.

On the other hand, when the refrigerant flows to the second sub-pipe 175, when the indoor operation of some indoor units of the plurality of indoor units during the heating operation, to reduce the amount of refrigerant. As such, when a part of the refrigerant discharged from the compressors 112 and 14 is bypassed to the second sub pipe 175, the amount of refrigerant corresponding to the indoor unit to be operated may be supplied to the indoor unit.

In this case, when the refrigerant is bypassed to the first sub pipe 174, it is required to quickly increase the suction pressure of the compressors 112 and 114, and the refrigerant is supplied to the second sub pipe 175. In the case of bypassing, it is required to continuously bypass a small amount of refrigerant to appropriately adjust the amount of refrigerant.

Therefore, in the present embodiment, the diameter or length of the first capillary 176 is larger than the second capillary 177 so that the refrigerant flow rate of the first sub pipe 174 is increased in the second sub pipe ( It is greater than the refrigerant flow rate of 175).

The heating operation and the cooling operation of the air conditioner will be briefly described.

First, during the cooling operation, the refrigerant discharged from the compressors 112 and 114 by controlling the flow path of the four-way valve 130 flows to the outdoor heat exchanger 150. Then, the refrigerant passing through the outdoor heat exchanger 150 is condensed. Thereafter, the refrigerant discharged from the outdoor heat exchanger 150 is expanded while passing through the indoor electromagnetic expansion valves 212, 222, and 232 after passing through the check valve 166. The expanded refrigerant is sucked into the compressors 112 and 114 through the accumulator 120 after being evaporated while passing through the indoor heat exchangers 211, 221, and 231.

On the other hand, during the heating operation, the refrigerant discharged from the compressors 112 and 114 by controlling the flow path of the four-way valve 130 flows to the indoor heat exchangers 211, 221, and 231. The refrigerant passing through the indoor heat exchangers 211, 221, and 231 is condensed. Thereafter, the refrigerant discharged from the indoor heat exchanger (211, 221, 231) is expanded while passing through the outdoor electronic expansion valve (160). The expanded refrigerant is sucked into the compressors 112 and 114 through the accumulator 120 after being evaporated while passing through the outdoor heat exchanger 150.

2 is a refrigerant cycle diagram illustrating a state in which refrigerant is bypassed to a first sub pipe.

Referring to FIG. 2, when the compressor is initially operated or when the suction pressure of the compressor is lower than the threshold pressure, the bypass valve 172 is opened and the bypass pipe is controlled by adjusting the flow path of the three-way valve 173. The refrigerant of 170 may be introduced into the first sub pipe 174. Here, the limit pressure refers to a pressure in a state in which the pressure of the compressor is low and the compressor is not stably operated.

At this time, the bypass of the refrigerant to the first sub pipe 174 may be performed in any case of cooling or heating operation. Hereinafter, the case of heating will be described as an example.

Therefore, some of the high pressure and high temperature refrigerant discharged from the compressors 112 and 114 are moved to the indoor heat exchanger 211, 221, 231 by adjusting the flow path of the four-way valve 130, and the other part of the refrigerant It flows into the bypass pipe 170. In addition, the refrigerant introduced into the bypass pipe 170 is moved to the first sub pipe 174. In addition, the refrigerant moved to the first sub pipe 174 is reduced in pressure while passing through the first capillary 176, and then flows into the accumulator 120.

As such, some of the high pressure and high temperature refrigerant discharged from the compressors 112 and 114 are moved to the suction side of the compressors 112 and 114 through the bypass pipe 170 and the first sub pipe 174. The suction pressure of the compressor can be increased.

When the suction pressure of the compressors 112 and 114 is increased, when the suction pressure reaches a threshold pressure or when a difference between the discharge pressure and the suction pressure of the compressors 112 and 113 reaches a reference pressure, Bypass valve 172 is closed.

3 is a refrigerant cycle diagram illustrating a state in which refrigerant is bypassed to a second sub pipe.

Referring to FIG. 3, when a part of a plurality of indoor units are operated during a heating operation, the bypass valve 172 is opened, and the refrigerant in the bypass pipe 170 is controlled by adjusting the flow path of the three-way valve 173. Is in a state capable of flowing into the second sub pipe 175.

In this embodiment, as an example, a case in which one indoor unit (the first indoor unit) of the plurality of indoor units is operated. At this time, when only the first indoor unit is operated, the refrigerant control valves 223 and 233 of the second indoor unit and the third indoor unit remain closed.

Therefore, some of the high pressure and high temperature refrigerant discharged from the compressors 112 and 114 are moved to the first indoor heat exchanger 211 by adjusting the flow path of the four-way valve 130, and the other part is the bypass pipe. Flows into 170. In addition, the refrigerant introduced into the bypass pipe 170 is moved to the second sub pipe 175. The refrigerant moved to the second sub pipe 175 is decompressed while passing through the second capillary 177 and then moved to the suction side of the outdoor heat exchanger 150. The refrigerant moved to the suction side of the outdoor heat exchanger 150 is combined with the refrigerant passing through the indoor heat exchanger 211 to pass through the outdoor heat exchanger 150.

In this case, more refrigerant than the capacity of the indoor unit to be operated is not flowed to the indoor unit, and as the amount of refrigerant corresponding to the capacity of the indoor unit (first indoor unit) to be operated flows to the first indoor unit, that is, the discharged from the compressor. As only a part of the refrigerant flows to the first indoor unit, the refrigerant noise due to the excessive flow of the refrigerant is removed.

1 is a refrigerant cycle configuration diagram of an air conditioner according to the present embodiment.

2 is a refrigerant cycle diagram illustrating a state in which refrigerant is bypassed to a first sub pipe.

3 is a refrigerant cycle diagram illustrating a state in which refrigerant is bypassed to a second sub pipe.

Claims (6)

An outdoor unit having a compressor and an outdoor heat exchanger; At least one indoor unit having an indoor heat exchanger; Four-way valve for adjusting the flow direction of the refrigerant discharged from the compressor; A main pipe configured to bypass a portion of the refrigerant discharged from the compressor; Bypass valve for controlling the flow of the refrigerant to the main pipe; A three-way valve provided in the main pipe; A first sub pipe connected to the three-way valve and the suction side of the compressor; And And a second sub pipe connected to the three-way valve and the outdoor heat exchanger side pipe. The method of claim 1, The first sub pipe is provided with a first capillary for reducing the refrigerant, The second sub pipe is provided with a second capillary, And an amount of refrigerant passing through the first capillary per unit time is greater than an amount of refrigerant passing through the second capillary. The method of claim 2, The diameter of the first capillary is formed larger than the diameter of the second capillary air conditioner. The method of claim 2, And the length of the first capillary is longer than the length of the second capillary. The method of claim 1, When the suction pressure of the compressor is lower than the threshold pressure, or at the initial start of the compressor, the bypass valve is opened, and the air conditioner in which the bypass pipe and the first sub pipe communicate with each other by adjusting the flow path of the three-way valve. group. The method of claim 1, The air conditioner of the plurality of indoor units when the indoor unit is heating operation, the bypass valve is opened, the bypass pipe and the second sub pipe communicates with each other by adjusting the flow path of the three-way valve.

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