KR19990084592A - Refrigerant flow control device of air conditioner - Google Patents

Abstract

The present invention relates to a refrigerant flow rate control apparatus of an air conditioner, so that the air conditioner is operated for a long time at a high frequency and the room is cooled in a comfortable state by adjusting the flow rate of the refrigerant flowing into the compressor when the compressor is overloaded. The consumer's reliability is to be improved.

To this end, the present invention provides a compressor (1) for compressing a refrigerant at a high temperature and high pressure, an outdoor heat exchanger (2) for condensing the refrigerant sent from the compressor (1) into a high pressure subcooled liquid, and the outdoor heat exchanger (2). In the refrigeration cycle of the air conditioner consisting of an expansion valve (3) for reducing the refrigerant sent to the low temperature and low pressure, and an indoor heat exchanger (4) for evaporating the refrigerant sent from the expansion valve (3) at a low temperature and low pressure. The solenoid valve 101 is opened between the expansion valve 3 and the indoor heat exchanger 4 so as to control the amount of refrigerant sent from the expansion valve 3 to the indoor heat exchanger 4.

Description

Refrigerant flow control device of air conditioner

The present invention relates to an air conditioner, and more particularly, to a refrigerant flow rate control apparatus of an air conditioner.

In general, an air conditioner inhales hot air in a room, exchanges the sucked hot air with cold air, and then discharges the cold air back into the room to cool the room to an appropriate temperature.

Now, the refrigeration cycle of the air conditioner is described as follows.

As shown in FIG. 1, the refrigeration cycle of the air conditioner includes a compressor (1) for compressing a refrigerant at high temperature and high pressure, and an outdoor heat exchanger (2) for condensing the refrigerant compressed in the compressor (1) with a high pressure subcooled liquid (2). ), An expansion valve (3) for reducing the refrigerant condensed in the outdoor heat exchanger (2) at low temperature and low pressure, and an indoor heat exchanger (4) for evaporating the refrigerant reduced in the expansion valve (3) at low temperature and low pressure. Consists of.

In the air conditioner refrigeration cycle of this structure, the refrigerant compressed at high temperature and high pressure in the compressor (1) is discharged from the compressor (1) and introduced into the outdoor heat exchanger (2), and the high temperature introduced into the outdoor heat exchanger (2). The high pressure refrigerant condenses into a high pressure subcooled liquid while undergoing heat exchange with outdoor air sucked into the outdoor unit.

The condensed high-pressure supercooled liquid is discharged from the outdoor heat exchanger (2) and passed through the expansion valve (3) to reduce the low-temperature low-pressure refrigerant, the reduced-temperature low-temperature low-pressure refrigerant is introduced into the indoor heat exchanger (4) As the heat exchanges with the hot air in the indoor unit, the refrigerant evaporates to the low temperature low pressure refrigerant, and the refrigerant evaporated to the low temperature low pressure flows back into the compressor 1 and is compressed into the high temperature high pressure refrigerant in the compressor 1. .

Such a refrigeration cycle is continued while the air conditioner is operating.

However, the refrigeration cycle of such a conventional air conditioner is introduced into the compressor after the refrigerant passes a constant length and internal diameter of the expansion valve having a constant length and inner diameter regardless of the high frequency or low frequency, so when the compressor is in a severe or overload condition, the top of the compressor The temperature sensor (not shown) attached thereto detects the temperature of the compressor and stops the air conditioner according to the detected signal, thereby preventing the temperature of the compressor from rising.

Therefore, if the air conditioner is operated at a high frequency, the temperature of the compressor is increased, and thus the air conditioner is not operated for a long time, and when operated at a low frequency, the user's reliability of the product is lowered because it does not give the user comfort. There was this.

The present invention has been made to solve the above problems, the air conditioner is operated for a long time at a high frequency and the room is cooled in a comfortable state by adjusting the flow rate of the refrigerant flowing into the compressor when the compressor is overloaded condition The purpose is to improve the consumer's reliability.

In order to achieve the above object, the present invention provides a compressor for compressing a refrigerant at high temperature and high pressure, an outdoor heat exchanger for condensing the refrigerant sent from the compressor into a high-pressure subcooled liquid, and a refrigerant sent from the outdoor heat exchanger at low temperature and low pressure. In the refrigeration cycle of the air conditioner consisting of an expansion valve for reducing the pressure and the indoor heat exchanger for evaporating the refrigerant sent from the expansion valve to a low temperature low pressure, the expansion valve is sent from the expansion valve to the indoor heat exchanger between the expansion valve and the indoor heat exchanger. Provided is a refrigerant flow rate control apparatus for an air conditioner, characterized in that a solenoid valve is opened and closed to control the amount of refrigerant.

1 is a cycle diagram showing a refrigeration cycle of a conventional air conditioner.

Figure 2 is an embodiment showing a refrigeration cycle of the air conditioner of the present invention.

Figure 3 is another embodiment showing a refrigeration cycle of the air conditioner of the present invention

Explanation of symbols for main parts of the drawings

3: first expansion valve 101: first solenoid valve

102: second expansion valve 103: second solenoid valve

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

Since the refrigeration cycle of the air conditioner has been mentioned in the conventional configuration, overlapping portions thereof will be omitted, and the same reference numerals will be used for the same structure.

Figure 2 is an embodiment showing a refrigeration cycle of the air conditioner of the present invention, the present invention is a compressor (1) for compressing the refrigerant at high temperature and high pressure, and the refrigerant sent from the compressor (1) condensed into a high-pressure supercooling liquid An outdoor heat exchanger (2), an expansion valve (3) for depressurizing the refrigerant sent from the outdoor heat exchanger (2) at low temperature and low pressure, and an interior for evaporating the refrigerant sent from the expansion valve (3) at low temperature and low pressure It consists of the heat exchanger (4).

Between the expansion valve (3) and the indoor heat exchanger (4) is provided a solenoid valve (101) which opens and closes to control the amount of refrigerant sent from the expansion valve (3) to the indoor heat exchanger (4).

That is, when the temperature of the compressor 1 is high, the solenoid valve 101 is opened to introduce a lot of refrigerant lower than the temperature of the compressor 1 into the compressor 1, and when the temperature of the compressor 1 is low, the solenoid valve ( The solenoid valve 101 is opened and closed so that the refrigerant 101 lower than the temperature of the compressor 1 flows into the compressor 1 by closing 101.

And, in another embodiment of the refrigeration cycle of the air conditioner of the present invention, as shown in Figure 3, between the expansion valve 3 and the indoor heat exchanger (4) is sent from the expansion valve (3) to the indoor heat exchanger (4) The solenoid valve 101 is opened and closed to control the amount of the refrigerant.

Another expansion valve 102 is provided to reduce a portion of the refrigerant discharged and branched from the outdoor heat exchanger 2 in parallel with the expansion valve 3 to a low temperature low pressure refrigerant, and the other expansion valve 102 is provided. Another solenoid valve 103 is connected in parallel with the solenoid valve 101 to be connected and decompressed to control the amount of refrigerant sent to the indoor heat exchanger 4 is reduced in pressure from the other expansion valve (102).

The other expansion valve 102 and the other solenoid valve 103 are connected in series.

Herein, the expansion valve 3 and the solenoid valve 101 are hereinafter referred to as the first expansion valve 3 and the first solenoid valve 101, and the other expansion valve 102 and the other solenoid valve 103 are as follows. It is referred to as second expansion valve 102 and second solenoid valve 104.

The operation of the present invention configured as described above is as follows.

First, the high temperature and high pressure refrigerant compressed by the compressor (1) flows into the outdoor heat exchanger (2), condenses into a high pressure subcooled liquid, and then decompresses to a low temperature low pressure while passing through the first expansion valve (3). The refrigerant reduced in pressure is introduced into the indoor heat exchanger 4 while the amount of the refrigerant is controlled in accordance with the first solenoid valve 101 to be opened and closed, evaporated to low temperature and low pressure, and then introduced into the compressor 1 again.

As described above, the inside of the refrigeration cycle of the air conditioner is always a certain amount of refrigerant flows to cool the room to the appropriate temperature.

At this time, when the temperature of the compressor 1 rises, that is, when the overload occurs in the compressor 1, the first solenoid valve 101 is opened, so that the outdoor heat exchanger 2 to the first expansion valve 3 is opened. The refrigerant, which is sent and passed through the first expansion valve 3 and reduced in pressure at low temperature and low pressure, passes through the opened first solenoid valve 101.

A large amount of the refrigerant passing through the first solenoid valve 101 is introduced into the indoor heat exchanger (4) to exchange heat with the hot air in the room to evaporate at low temperature and low pressure, and the evaporated refrigerant is indoor heat exchanger (4). Is discharged into the compressor (1).

Since the temperature of the refrigerant introduced into the compressor 1 is lower than the temperature of the compressor 1, the temperature of the compressor 1 is lowered by many refrigerants introduced into the compressor 1.

In this case, when the temperature of the compressor 1 decreases, the first solenoid valve 101 is closed, and thus the first solenoid valve 101 which is closed at a low pressure and low pressure while passing through the first expansion valve 3 is closed by the first solenoid valve 101. A small amount flows into the compressor 1 and the air conditioner is operated while the temperature of the compressor 1 is kept constant.

As described above, as the compressor 1 controls the flow of the refrigerant for each frequency caused by the variable compression of the refrigerant according to the load change in the air conditioner, the temperature of the compressor 1 is not only prevented from rising. The load on the compressor 1 is reduced.

That is, the temperature sensor (not shown) attached to the upper end of the compressor 1 senses the temperature of the compressor 1 and when the detected temperature rises above a certain temperature, the first solenoid valve 101 is opened in the microcomputer, and When the temperature of the compressor 1 falls below a certain temperature, the first solenoid valve 101 is closed to adjust the amount of refrigerant flowing into the compressor 1, so that the air conditioner is not overloaded in the compressor 1 without causing an overload. Long time operation is possible in.

In addition, when the temperature of the compressor (1) is excessively increased, the oil temperature in the compressor (1), the temperature of the oil rises and the viscosity decreases, slugs are generated, which controls the amount of refrigerant flowing into the compressor (1) By controlling the overload of the compressor 1, the slug or viscosity of the oil in the compressor 1 is prevented.

Here, the temperature of the refrigerant flowing into the compressor 1 after being evaporated to low temperature and low pressure while passing through the indoor heat exchanger 4 while being decompressed to the low temperature and low pressure in the first expansion valve 3 is 13 ° C. Lower than the temperature of).

In addition, as shown in FIG. 3 as another embodiment of the refrigeration cycle of the air conditioner, the refrigerant compressed by the high temperature and high pressure in the compressor (1) is introduced into the outdoor heat exchanger (2) to exchange heat with outdoor air Condensed into a high pressure subcooled liquid.

The condensed refrigerant is discharged from the outdoor heat exchanger (2) to flow into the first expansion valve (3), a portion of the refrigerant is branched into the second expansion valve (102), and the first expansion valve (3). A portion of the refrigerant flowing into the second expansion valve 102 and the refrigerant flowing into the second expansion valve 102 are decompressed to the low temperature and low pressure refrigerant while passing through the first and second expansion valves 3 and 102.

The refrigerant depressurized by the first expansion valve (3) passes through the first solenoid valve (101), flows into the indoor heat exchanger (4), evaporates into a refrigerant of low temperature and low pressure, and passes through the second expansion valve (102). While a portion of the refrigerant decompressed is introduced into the indoor heat exchanger 4 while the amount of refrigerant is controlled by the second solenoid valve 103 which is opened and closed, the refrigerant is evaporated into the refrigerant having a low temperature and low pressure. As the heat is exchanged with the hot air, the temperature is increased, that is, the refrigerant evaporated to low temperature and low pressure is introduced into the compressor 1 and compressed to high temperature and high pressure.

At this time, when the temperature of the compressor 1 rises in an overload state of the air conditioner, the first solenoid valve 101 and the second solenoid valve 103 are all opened or the first solenoid valve 101 is opened. In the state, the second solenoid valve 103 is repeatedly opened and closed, that is, the second solenoid valve 103 is opened or repeatedly opened or closed depending on the temperature of the compressor 1 and the amount of refrigerant flowing into the compressor 1. Done.

Therefore, the refrigerant sent from the outdoor heat exchanger (2) to the first expansion valve (3) is decompressed to low temperature and low pressure while passing through the first expansion valve (3), and the second expansion valve in the outdoor heat exchanger (2). A portion of the refrigerant sent to 102 is reduced to low temperature and low pressure while passing through the second expansion valve 102.

As described above, the refrigerant decompressed while passing through the first expansion valve 3 flows into the indoor heat exchanger 4 through the opened first solenoid valve 101 and passes through the second expansion valve 102. The reduced pressure refrigerant is introduced into the indoor heat exchanger (4) while the amount of the refrigerant is controlled by the second solenoid valve (103), which is open or repeatedly opened or closed.

The refrigerant introduced into the indoor heat exchanger (4) is heat exchanged with hot air in the room to evaporate at low temperature and low pressure, and the evaporated refrigerant is discharged from the indoor heat exchanger (4), and a large amount flows in the compressor (1). Since the temperature of the refrigerant flowing into the compressor 1 is lower than the temperature of the compressor 1, the temperature of the compressor 1 is lowered, so that the overload of the compressor 1 is prevented and the air conditioner operates smoothly at a high frequency.

Here, when the temperature of the compressor 1 decreases, the second solenoid valve 103 is closed, so that the refrigerant discharged from the outdoor heat exchanger 2 does not flow into the second expansion valve 102, but the first expansion valve 3 is closed. ) Is passed through the first expansion valve (3) to reduce the low temperature and low pressure, and then flows into the indoor heat exchanger (4) through the open first solenoid valve (101) and evaporates, and evaporates and into the compressor (1). Since a small amount of refrigerant is introduced again, the air conditioner is operated while the temperature of the compressor 1 is kept constant.

That is, when only one expansion valve is installed as described above, the solenoid valve is periodically opened and closed to control the flow rate of the refrigerant.

When two or more expansion valves are installed, the solenoid valve is opened to allow the refrigerant to pass through only one expansion valve at the main operation frequency, and the flow rate of the refrigerant passing through the remaining expansion valve is controlled while the remaining solenoid valve is repeatedly opened and closed. .

At this time, when the main operation frequency is not, the flow rate of the refrigerant is controlled while repeatedly opening or closing one or two solenoid valves so that the refrigerant passes through the one or two expansion valves alternately.

As described above, according to the present invention, the compressor multi-stage variable compression of the refrigerant according to the load change in the air conditioner, thereby preventing the temperature of the compressor from rising excessively by controlling the flow of the refrigerant for each frequency generated. The load of is reduced.

That is, by sensing the temperature of the compressor to open the solenoid valve in the microcomputer if the temperature is above a certain temperature, and close the solenoid valve when the temperature falls below the predetermined temperature to control the flow rate of the refrigerant flowing into the compressor, not only the compressor is overloaded. Since the burnout of the compressor is prevented, the performance of the compressor is improved.

In addition, by controlling the amount of refrigerant flowing into the compressor of the air conditioner, the overload of the compressor is prevented, so that the air conditioner can be operated for a long time at a high frequency, the room is cooled quickly to the appropriate temperature while maintaining a comfortable state the defrosting There is also the effect of improving the consumer's confidence in the.

Claims (2)

A compressor for compressing the refrigerant at a high temperature and high pressure, an outdoor heat exchanger for condensing the refrigerant sent from the compressor into a high pressure subcooled liquid, an expansion valve for reducing the refrigerant sent from the outdoor heat exchanger to a low temperature and a low pressure, and the expansion valve In the refrigeration cycle of the air conditioner consisting of an indoor heat exchanger for evaporating the refrigerant sent to low temperature low pressure, And a solenoid valve which is opened and closed between the expansion valve and the indoor heat exchanger to control the amount of refrigerant sent from the expansion valve to the indoor heat exchanger. The method of claim 1, Another expansion valve for reducing a portion of the refrigerant discharged and branched from the outdoor heat exchanger into a low temperature low pressure refrigerant in parallel with the expansion valve, and connected to the other expansion valve to reduce the pressure from the other expansion valve to the indoor heat exchanger Refrigerant flow control device of the air conditioner, characterized in that the solenoid valve is opened in parallel with the solenoid valve to open and close to control the amount of air.