KR20060077217A - Airconditioner having a oil seperator and control method of an airconditioner's oil seperator - Google Patents

Abstract

The present invention relates to an air conditioner equipped with an oil separator and an oil separator control method of an air conditioner, wherein the oil separator control method includes a special situation in which an abnormally large amount of oil is discharged from a compressor in a state of an air conditioner. Determining the recognition, turning on the bypass valve if it is determined that the special situation, and if the continuous operation time of the compressor is greater than or equal to B minutes, if it is determined that the special situation is not the bypass. And turning on the valve. Therefore, it is possible to prevent the oil accumulated in the oil separator from being introduced into other equipment of the air conditioner such as an indoor heat exchanger, so that the efficiency of the air conditioner caused by the oil discharged from the compressor into the other equipment of the air conditioner is reduced. Problems can be prevented.

Air Conditioner, Oil Separator, Bypass, Bypass Pipe, Solenoid, Oil

Description

Air conditioner having a oil seperator and control method of an airconditioner's oil seperator

1 is a configuration diagram of a refrigerant cycle of a general multi-type air conditioner.

2 is a schematic configuration diagram of a multi-type air conditioner with an oil separator according to the present invention.

3 is a flowchart illustrating a method of controlling an oil separator of an air conditioner according to the present invention.

* Description of the symbols for the main parts of the drawings *

140: indoor unit 180: outdoor unit

182: inverter compressor 184: constant speed compressor

186: first oil separator 188: second oil separator

200: valve for the first bypass 300: valve for the second bypass

202: piping for the first bypass 302: piping for the second bypass

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner and a control method thereof, and more particularly to an air conditioner and an air conditioner having an oil separator capable of efficiently removing oil accumulated in an oil separator by suction of a compressor. A method for controlling separators.

An air conditioner is a device that is arranged in a room, living room, office, or business store to adjust the temperature, humidity, cleanliness, and airflow of the air to maintain a comfortable indoor environment. It is divided into (seperate type or split type).

The integrated type and the separated type are functionally the same, but the integrated type integrates the functions of cooling and heat dissipation to install a hole in the wall of the house or hang the device on the window, and the separate type installs an indoor unit that performs cooling / heating on the indoor side. In addition, the outdoor unit installed the outdoor unit that performs the heat dissipation and compression function, and then connected the two separate devices by the refrigerant pipe.

In general, one outdoor unit is installed in correspondence with one indoor unit. However, in the case of a building having several rooms, several outdoor units must be purchased to correspond to the indoor unit installed in each room. It is not efficient in terms of space use only when a certain area of space is secured for each outdoor unit.

Therefore, the development of a multi-type air conditioner capable of cooling and heating several rooms at once by connecting several indoor units to one outdoor unit is actively progressing.

1 is a configuration diagram of a refrigerant cycle of a general multi-type air conditioner.

The multi-type air conditioner includes an indoor unit (10) having a plurality of indoor heat exchangers (11a, 11b, 11c) arranged in the room and performing cooling / heating functions, and an outdoor unit (1) arranged outdoors. .

The outdoor unit (1) has an inverter compressor (2) and a constant speed compressor (3) for compressing the refrigerant, an outdoor heat exchanger (5) for dissipating the compressed refrigerant, and the outdoor heat exchanger (5). And a cooling fan 6 arranged at the rear of the pump to promote heat dissipation of the refrigerant.

In the cooling operation, a main electromagnetic expansion valve 12 is provided downstream of the outdoor heat exchanger 5 along the flow direction of the refrigerant, and a refrigerant is provided at a downstream side of the main electromagnetic expansion valve 12. Sub solenoid expansion valves 13a, 13b, and 13c are provided to allow expansion under reduced pressure before they are introduced into 11b and 11c, respectively. First temperature sensors 15a, 15b, and 15c are provided to detect the temperature of the refrigerant discharged from 11a, 11b, and 11c.

Meanwhile, the constant speed compressor 3 and the inverter compressor 2 each have a compression capacity corresponding to half (50%) of the maximum air-conditioning load of the indoor unit 1, and each discharge side has a refrigerant having an outdoor heat exchanger 5. The second temperature detecting sensor 4 is joined to each other before being introduced into the first and second condensing zones.

Next, the cooling process of the multi-type air conditioner will be described.

The high temperature and high pressure gas refrigerant compressed by the compressors 2 and 3 is guided to the outdoor heat exchanger 5 by four sides (not shown), and then condensed in the process of passing through the outdoor heat exchanger 5 to obtain a high temperature. Phase change by high pressure liquid refrigerant. The high temperature and high pressure liquid refrigerant from the outdoor heat exchanger (5) flows into the main electromagnetic expansion valve (12), and then passes through the sub solenoid expansion valves (13a, 13b, 13c) to a state of low temperature and low pressure, and then indoors. It flows into the heat exchangers 11a, 11b, 11c. At this time, the introduced refrigerant is converted into a gaseous refrigerant by evaporation, and guided to the suction side of the compressors 2 and 3 by four sides (not shown).

At this time, the refrigerant passing through the indoor heat exchangers (11a, 11b, 11c) takes heat away from the air in the room and evaporates, and thus the air conditioning space is repeatedly cooled and the temperature thereof decreases.

Compared to a general air conditioner using only one indoor unit connected to one outdoor unit, the above-described multi-type air conditioner can cool / heat several rooms at the same time by using one outdoor unit. It is advantageous.

On the other hand, in the multi-type air conditioner system, when the refrigerant is discharged to the discharge ends of the compressors 2 and 3, oil existing in the compressor may also be discharged. The discharged oil is introduced into the indoor heat exchangers (11a, 11b, 11c) together with the refrigerant and accumulated therein. As the accumulation of these oils increases, the heat exchange efficiency of the indoor heat exchanger decreases gradually. It causes a problem of lowering the efficiency of the whole machine.

In order to solve the above problem, an oil separator (not shown) is installed at the discharge ends of the compressors 2 and 3 to separate oil from the refrigerant and to flow it into the compressor. Oil and refrigerant are physically separated from each other because of their inherent physical properties. The oil separator is thus separated and the refrigerant in the oil is sent in all directions, and the oil is passed through the piping for bypass. It serves to send to the suction of the compressor.

Therefore, when the oil separator is used, even if oil is discharged together with the refrigerant to the discharge ends of the compressors 2 and 3, only the oil can be separated from the refrigerant and sent to the suction ends of the compressors 2 and 3, thereby providing an indoor heat exchanger. It is possible to prevent the situation in which the oil is introduced, such as to solve the problem that the efficiency of the air conditioner is reduced.

However, according to the conventional oil separation method of sending the oil separated from the refrigerant in the oil separator to the suction end of the compressor using a bypass pipe, it is efficient in that the oil accumulated in the oil separator can be immediately and steadily removed. In certain situations, such as when a large amount of oil accumulates within the oil separator within a short time, for example, when the compressor is started at an early stage or when the compressor is started with an extremely low outdoor temperature, the diameter of the bypass pipe is reduced. There is a problem in that the small oil does not efficiently remove the accumulated oil in the oil separator.

SUMMARY OF THE INVENTION An object of the present invention is to provide an air conditioner having an oil separator capable of efficiently removing oil even in a special situation such as a large amount of oil accumulating in a short time inside the oil separator.                         

Another object of the present invention is to provide an oil separator control method of an air conditioner that can efficiently remove oil accumulated in the oil separator to the suction end of the compressor.

In order to achieve the above object, an air conditioner having an oil separator according to the present invention includes an oil separator (186, 188) mounted at a discharge end of a compressor (182, 184), between the oil separator and the suction end of the compressor. Bypass pipes 202 and 302 installed in the oil separator to discharge oil accumulated in the oil separator, and bypass valves 200 and 300 mounted on the bypass pipe to control the opening and closing of the bypass pipe. It is characterized by comprising:

At this time, the bypass pipe (202, 302) is the diameter of the oil is accumulated in the oil separator when a special situation occurs when an unusually large amount of oil is discharged from the compressor flows into the other device of the air conditioner together with the refrigerant It is preferable that it is large enough to drain the oil so as not to go, and it is preferable that the bypass valves 200 and 300 are solenoid valves.

In order to achieve the above object, the oil separator control method of the air conditioner according to the present invention comprises the steps of: determining whether the state of the air conditioner is a special situation in which an unusually large amount of oil is discharged from the compressor; Turning on the bypass valve if it is determined to be a situation; turning on the bypass valve if the continuous operation time of the compressor is greater than or equal to B minutes if it is determined that the It is characterized by including.

At this time, the special situation is preferably any one of the state in which the compressor is initially started and A minute has not elapsed and the outdoor temperature is T ° C. or lower, and it is determined that the continuous operation time of the compressor is B minute or more, and the bypass valve is used. In the step of turning ON, the bypass valve is preferably kept ON for only C seconds.

Therefore, according to the present invention, it is possible to prevent the oil accumulated in the oil separator from being introduced into other devices of the air conditioner such as an indoor heat exchanger, so that the air generated by the oil discharged from the compressor is introduced into the other devices of the air conditioner. It is possible to prevent the problem of deterioration of the conditioner.

Hereinafter, an air conditioner having an oil separator and an oil separator control method of an air conditioner according to the present invention will be described in detail with reference to the accompanying drawings.

2 is a schematic configuration diagram of a multi-type air conditioner having an oil separator according to the present invention, and shows a multi-type air conditioner in which a indoor unit of a generation is connected to one outdoor unit.

An indoor unit 140 having an indoor heat exchanger 142 and an indoor fan 144 is installed in the room, and the indoor unit 140 is connected to an outdoor unit 180 installed outside the room through a pipe. It is.

The outdoor unit 180 is equipped with a multi-type compressor composed of an inverter compressor 182 and a constant speed compressor 184. These compressors are devices for compressing and discharging a refrigerant circulating in an air conditioner at high temperature and high pressure. The discharge ends of the compressors 182 and 184 are equipped with first and second oil separators 186 and 188 for separating the refrigerant and the oil, respectively. The oil separator is an apparatus for separating oil discharged together with the refrigerant from the discharge end of the compressor from the refrigerant and then recycling the oil to the compressor.

As described above, since the oil and the refrigerant are physically separated from each other because of their inherent physical properties, the oil and the refrigerant discharged together from the discharge end of the compressor are separated by different layers after being sucked into the oil separator. It will exist.

First and second bypass pipes 202 and 302 connecting the oil separators 186 and 188 and the suction ends of the compressors 182 and 184 to the sides of the oil separators 186 and 188, respectively. Each of these is installed. The oil separated from the refrigerant in the oil separator flows to the suction end of the compressor through the bypass pipes 202 and 302. That is, the first bypass pipe 202 serves as a passage in circulating the oil inside the first oil separator 186 to the inverter compressor 182, and the second bypass pipe 302 is the second. It serves as a passage for circulating oil inside the oil separator 188 to the constant speed compressor 184.

The first and second bypass pipes 202 and 302 are configured to have a larger diameter than the conventional bypass pipe, which flows a large amount of oil all at once to the suction end of the compressor in a short time. To make it possible to send. In the case of the bypass pipe of the small diameter, it is easy to remove the oil accumulated in the oil separator steadily from time to time, but in a special situation in which a large amount of oil accumulates in a short time, such as the initial startup of the compressor or the outdoor temperature In a situation such as starting a compressor in a state, there is a problem that a large amount of oil accumulated in a short time cannot be removed efficiently. However, according to the bypass pipe according to the present invention, since the diameter thereof is larger than that of the related art, oil accumulated rapidly in the oil separator can be discharged to the suction end of the compressor in a short time even in the above-mentioned special situation.

In this case, the diameters of the first and second bypass pipes 202 and 302 may not flow into other devices such as the four sides 192 together with the refrigerant when the oil accumulated in the oil separator occurs in the above-mentioned special situation. If it is large enough to drain the oil quickly and the accumulated oil is discharged so quickly that the refrigerant that should flow to other devices such as the four sides 192 is not discharged to the suction end of the compressor. Appropriate, this is determined by experiment taking into account various parameters of the air conditioner, such as the capacity of the compressor, the capacity of the indoor unit, and the like.

Meanwhile, the first and second bypass pipes 202 and 302 are equipped with first and second bypass valves 200 and 300, respectively, for controlling the opening and closing of the pipe. It is. These bypass valves 200 and 300 are for controlling the flow of oil flowing through the bypass pipes 202 and 302. On / off, that is, opening and closing of the valves is controlled by an air conditioner. It is designed to be controlled by At this time, the bypass valve, for example, uses a valve such as a solenoid (solenoid valve).

When a special situation as described above occurs in which a large amount of oil is discharged within a short time from the discharge ends of the compressors 182 and 184, the controller (not shown) may control the bypass valves 200 and 300 for a predetermined time. By turning on, the oil accumulated in the oil separators 186 and 188 is discharged to the suction ends of the compressors 182 and 184 through the bypass pipes 202 and 302. At this time, the bypass pipes 202 and 302 have a larger diameter than the conventional bypass pipes as described above, so that a large amount of oil can be discharged without clogging in a short time.

Meanwhile, after the refrigerant discharged from the inverter compressor 182 and the constant speed compressor 184 passes through the first oil separator 186 and the second oil separator 188, respectively, the oil contained therein is removed, and then oil is joined. Through the pipe 189 is introduced into the four sides 192 in a state joined with each other.

The four sides 192 is a device for changing the flow of the refrigerant flowing into or out of the compressors 182 and 184 according to each operation mode when the air conditioner is operated in the cooling or heating operation, in the case of the cooling operation The refrigerant flows in and out in the direction indicated by the solid arrows in FIG. 2, and the refrigerant flows in and out in the direction indicated by the dotted arrows in FIG. 2 in the heating operation. Therefore, the refrigerant discharged from the compressors 182 and 184 is introduced into the outdoor heat exchanger 194 in the case of cooling by the action of the four-sided side 192, and in the case of heating, the indoor unit 140. Flows into.

One end of the outdoor heat exchanger 194 is connected to the four sides 192, the other end is connected to the electromagnetic expansion valve 162. Therefore, the refrigerant passing through the outdoor heat exchanger 194 and heat exchanged with the outdoor air passes through the electronic expansion valve (LEV) 162. The electronic expansion valve 162 expands the refrigerant under reduced pressure to convert it into a low temperature low pressure refrigerant. In this case, the refrigerant that is phase-converted to low temperature and low pressure while passing therethrough is introduced into the indoor unit 140 after passing through the receiver 164 and the dry gear 166.

The low temperature low pressure refrigerant introduced into the indoor unit 140 lowers the temperature of the indoor (ie, air conditioning space) through heat exchange with the indoor air passing through the indoor heat exchanger 142 by the action of the indoor fan 144. .

On the other hand, since the indoor unit 140 is one end is connected to the four sides 192, the refrigerant after the heat exchange through the indoor heat exchanger 142 flows to the four sides 192, the induction of the four sides 192 It is introduced into the accumulator (190) by the. The accumulator 190 is connected to the suction end of the inverter compressor 182 and the constant speed compressor 184, which means that the unvaporized liquid refrigerant is introduced into the compressors 182 and 184 while passing through the indoor unit 140. It serves to prevent.

According to the air conditioner including the oil separator according to the present invention, a bypass pipe having a larger diameter than the conventional one and a bypass valve for controlling the opening and closing of the pipe are installed between the oil separator and the suction end of the compressor. Then, when an abnormal situation such as a large amount of oil is discharged within a short time in the compressor of the air conditioner, by controlling the bypass valve to smoothly discharge the oil in the oil separator to the suction end of the compressor, Since oils in the oil separator can be prevented from flowing to other devices of the air conditioner, such as an indoor heat exchanger, it is possible to prevent a decrease in efficiency of the air conditioner.

3 is a flowchart illustrating a method of controlling an oil separator of an air conditioner according to the present invention.

When the user adjusts the key input unit of the air conditioner to allow the air conditioner to enter the operating state (step S100), the control unit first checks whether the compressors 182 and 184 of FIG. 2 are in an initial starting state. Usually, since the amount of oil discharged from the compressor is larger than the normal state when the compressor is in the initial starting state, the controller checks whether the current state is abnormally discharged or a normal state.

If it is determined that the compressor is operating in the initial starting state for A minute, for example, not more than 20 minutes (step S110), the controller determines that a large amount of oil is being discharged from the compressor of the air conditioner within a short time. By turning on the bypass valves (200 and 300 of FIG. 2) to control the closing and opening of the bypass pipe (202 and 302 of FIG. 2) (step S150), the oil separator (186 and FIG. 2). The oil accumulated in 188 is discharged to the suction end of the compressor (182 and 184 of FIG. 2).

At this time, the bypass pipe, as described in Figure 2, because the diameter is large enough to efficiently discharge a large amount of oil discharged during the initial startup of the compressor, the oil separator in a short time step S150 A large amount of oil accumulated in the inside can be removed without difficulty.

On the other hand, if it is determined in step S110 that the compressor is operating in the state where A minutes have elapsed from the initial startup state, the control unit determines that the abnormal oil ejection state occurring for a few minutes during the initial startup of the compressor is finished, the air conditioner It is determined whether the current state of the other conditions that discharge a large amount of oil from the compressor in a short time, that is, the outdoor temperature is less than T ℃ (step S120).

Subsequently, when it is determined that the outdoor temperature is equal to or lower than T ° C., for example, 0 ° C. (step S120), the controller determines that a large amount of oil is currently being discharged from the compressor of the air conditioner within a short time. By accumulating in the oil separator (186 and 188 in FIG. 2) by turning on the bypass valve (200 and 300 in FIG. 2) to control the closing and opening of (202 and 302 in FIG. 2) (step S150). The oil present is discharged to the suction end of the compressor (182 and 184 in FIG. 2).

At this time, the bypass pipe, as described in Figure 2, because the diameter is large enough to efficiently discharge a large amount of oil discharged during the initial startup of the compressor, the oil separator in a short time step S150 A large amount of oil accumulated in the inside can be removed without difficulty.

On the other hand, if it is determined in step S120 that the outdoor temperature is not equal to or less than T ℃, the control unit determines that the current air conditioner is not an abnormal oil ejection state of the compressor that occurs when the outdoor temperature is a low temperature state, the compressor continues, It is determined whether the continuous drive time of B is, for example, 5 minutes or less (step S130).

If the continuous running time of the compressor is less than B minutes, it is determined that the amount of oil discharged with the refrigerant during the compressor operation and accumulated in the oil separator is not large enough to be discharged to the suction stage of the compressor, so that the oil separator (FIG. 2) 186 and 188) to maintain the bypass valve is turned off (OFF) so that the oil accumulated in the compressor does not flow to the suction end of the compressor (step S160).

On the other hand, if it is determined in step S130 that the continuous drive time of the compressor is more than B minutes, it is determined that the amount of oil discharged together with the refrigerant when the compressor is driven and accumulated in the oil separator is large enough to be discharged to the suction end of the compressor. Thus, the bypass valve is turned on for C seconds, for example, 5 seconds (step S140) so that oil accumulated in the oil separator flows to the suction end of the compressor (step S150). At this time, referring to step S140, it can be seen that the bypass valve is controlled to turn off automatically when C seconds have elapsed after being turned on.

In the steps S130, S140, S150 and S160, even if an abnormally large amount of oil is discharged within a short time in the compressor, the bypass valve is opened for C seconds when the normal compressor operation time is continuous for more than B minutes. It is a process to discharge the oil accumulated in the separator to the suction end of the compressor. Since the bypass pipe according to the present invention has a larger diameter than the conventional one, the amount of oil accumulated in the oil separator during the continuous operation time of the compressor is also large in a short time (that is, during C seconds). Of course, oil can be discharged to the suction end of the compressor without difficulty.

According to the oil separator control method of the air conditioner and the air conditioner equipped with the oil separator according to the present invention, first, by increasing the diameter of the bypass pipe than conventional, a large amount of oil to the suction end of the compressor in a short time If it is judged that the amount of oil accumulated in the oil separator is large by installing a bypass valve for controlling the opening and closing of the bypass pipe, the oil is accumulated in a short time by opening the valve. To be discharged to the suction end of the compressor.

In this case, the bypass valve is discharged in an unusually large amount of oil from the compressor, for example, when the compressor is started at a time when the water or outdoor temperature is less than T ℃, and the compressor is continuously operated for more than B minutes. The control to open (ON) makes it possible to efficiently remove oil accumulated in the oil separator.

Therefore, it is possible to prevent the oil accumulated in the oil separator from being introduced into other equipment of the air conditioner such as an indoor heat exchanger, so that the efficiency of the air conditioner caused by the oil discharged from the compressor into the other equipment of the air conditioner is reduced. Problems can be prevented.

Claims (6)

Oil separators 186 and 188 mounted at the discharge ends of the compressors 182 and 184; A bypass pipe (202, 302) installed between the oil separator and the suction end of the compressor to discharge oil accumulated in the oil separator; And And a bypass valve (200, 300) mounted to the bypass pipe to control the opening and closing of the bypass pipe. The method of claim 1, The bypass pipes 202 and 302 may not flow the oil accumulated in the oil separator together with the refrigerant into other devices of the air conditioner when a special situation occurs in which the diameter is abnormally large amount of oil is discharged from the compressor. An air conditioner with an oil separator, characterized in that the size is enough to discharge the oil quickly enough. The method of claim 1, The air conditioner having an oil separator, characterized in that the bypass valve (200, 300) is a solenoid valve. Determining whether the condition of the air conditioner is a special situation in which an abnormally large amount of oil is discharged from the compressor; If it is determined that the special situation, turning on the bypass valve (ON); If it is determined that the special situation is not, the control method of the oil separator of the air conditioner comprising the step of turning on (by) the bypass valve when the continuous drive time of the compressor is B minutes or more. The method of claim 4, wherein The special situation is the oil separator control method of the air conditioner, characterized in that any one of the state in which the compressor is initially started and the A minute has not elapsed and the outdoor temperature is below T ° C. The method of claim 4, wherein In the step of turning on the bypass valve because it is determined that the continuous drive time of the compressor is equal to or greater than B minutes, the bypass valve is kept ON for only C seconds. To control the oil separator of the machine.

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