KR20200122774A - Air Conditioning System applying expander - Google Patents

Abstract

The present invention relates to an air conditioning system and a control method thereof, and more specifically, to an air conditioning system having an expander. The air conditioning system includes: a compressor having a refrigerant inlet and a refrigerant outlet, wherein the refrigerant outlet is provided in a discharge chamber to compress the refrigerant; a condenser condensing and liquefying the high-temperature and high-pressure refrigerant discharged from the compressor; the expander having the refrigerant inlet and the refrigerant outlet, wherein the refrigerant outlet is provided in the discharge chamber, and sucking and expanding the refrigerant to convert the refrigerant into shaft power; an evaporator for heat exchange by evaporating a liquid refrigerant expanded in the expander; a first oil path connected between the discharge chamber of the compressor and the refrigerant inlet of the expander; and a second oil path connected between the discharge chamber of the expander and the refrigerant inlet of the compressor.

Description

Air Conditioning System applying expander

The present invention relates to an air conditioning system and a control method thereof, and more particularly, to an air conditioning system to which an expander is applied.

The air conditioning system is a device that controls a predetermined space to a desired temperature and humidity. In general, the air conditioning system uses a refrigeration cycle. The refrigeration cycle constitutes a closed circuit including a compressor, an evaporator, an expansion valve, and a condenser. The refrigerant circulates inside the closed circuit of the refrigeration cycle. When the refrigerant phase changes in the evaporator and condenser, it absorbs heat from the surroundings or releases heat to the surroundings. Using this, a predetermined space is controlled to a desired temperature and humidity.

In order to improve the efficiency of performance in air conditioning systems, an expander may be used instead of or in conjunction with an expansion valve. The expander is a component that, in contrast to the compressor, sucks a refrigerant with high energy at high temperature and high pressure, expands it, and converts it into shaft power.

In a general air conditioning system, that is, an air conditioning system using an expansion valve, the air conditioning system is controlled by the operating speed of the compressor, the temperature pressure at the compressor inlet, the compressor outlet pressure, and the opening amount of the expansion valve. On the other hand, in the air conditioning system to which the expander is applied, in addition to the above control items, a variable called the operation speed of the expander is added to change the concept of air conditioning system control.

However, in the prior art, mainly improvements have been proposed with respect to the configuration of the air conditioning system, the basic concept or the structure of the expander. In other words, when the expander is applied in an air conditioning system, control in consideration of the performance aspect of the system, which is actually a problem, is not generally considered.

Therefore, when an expander is applied in an air conditioning system, a device and control in consideration of the performance of the air conditioning system are required.

The present invention is to solve the above-described problem, and an object of the present invention is to provide an air conditioning system capable of improving the performance of the system while applying an expander.

In addition, by using the pressure difference between the outlet of the compressor and the condenser and the pressure difference between the outlet of the expander and the evaporator, to provide an air conditioning system including an efficient oil and refrigerant circulation path.

In addition, a separate oil separator and oil pump are not required, and an air conditioning system capable of effectively circulating oil is provided.

In addition, it is to provide an air conditioning system capable of removing a pressure reducing device for an oil circulation system inside a compressor.

In order to solve the problem of the present invention, in an air conditioning system to which a compressor and an expander are applied, separation using a path for injecting separated oil to the inlet of the expander through an oil separator inside the compressor and an oil separator installed at the outlet of the expander It can provide a path for injecting oil into the inlet of the compressor.

In the present invention, in a refrigerant circulation system comprising a compressor, a condenser, an expander, and an evaporator, a first oil path connected between a discharge chamber of the compressor and a refrigerant inlet of the expander, and a discharge chamber of the expander and a refrigerant inlet of the compressor It may be configured to include a second oil path connected to.

Specifically, the present invention provides an air conditioning system comprising: a compressor having a refrigerant suction port and a refrigerant discharge port, and the refrigerant discharge port is provided in the discharge chamber to compress the refrigerant; A condenser for condensing and liquefying the high temperature and high pressure refrigerant discharged from the compressor; An expander provided with a refrigerant suction port and a refrigerant discharge port, and the refrigerant discharge port is provided in a discharge chamber, which sucks and expands the refrigerant to convert it into axial power; An evaporator for heat exchange by evaporating the liquid refrigerant expanded in the expander; A first oil path connected between the discharge chamber of the compressor and the refrigerant inlet of the expander; And a second oil path connected between the discharge chamber of the expander and the refrigerant inlet of the compressor.

In addition, the first oil path may be connected to a first refrigerant path connected between the condenser and the inlet of the expander.

In addition, the second oil path may be connected to a second refrigerant path connected between the evaporator and the suction port of the compressor.

In addition, the first oil path may be connected to a lower end of the discharge chamber of the compressor to which the oil separated from the discharge chamber of the compressor descends.

In addition, the second oil path may be connected to a lower end of the discharge chamber of the expander to which oil separated from the discharge chamber of the expander descends.

In this case, an oil separator for separating the oil from the refrigerant may be provided in the discharge chamber of the expander.

In addition, the expander may include a housing having an inlet and a discharge port of the refrigerant and forming an inner space; A motor installed in the inner space of the housing to generate a rotational force and including a stator and a rotor rotating with respect to the stator; A rotating shaft coupled to the rotor of the motor to rotate; A rotating shaft coupled to the rotor and rotating; A frame installed on one side of the motor to support the rotation shaft; A fixed scroll coupled to the frame to form a compression space; And an orbiting scroll eccentrically coupled to the rotating shaft, located in the compression space, and coupled to the fixed scroll to perform orbiting motion to compress fluid.

In addition, the discharge chamber of the expander may be installed outside the housing on the opposite side of the fixed scroll.

In addition, the inlet of the expander may be provided on the fixed scroll.

In addition, the fixed scroll of the expander may constitute an outer housing.

The present invention has the following effects.

First, it is possible to prevent a decrease in system efficiency due to oil accumulation in the evaporator and condenser.

In addition, a separate oil separator and oil pump may not be required in the air conditioning system. Thus, the overall system can be simplified and the manufacturing cost can be reduced.

Moreover, according to this simplified structure, the efficiency of the entire air conditioning system can be increased.

In addition, it is possible to remove the pressure reducing device for the oil circulation system inside the compressor. Accordingly, the manufacturing cost of the compressor can be reduced.

Further scope of applicability of the present invention will become apparent from the detailed description below. However, since various changes and modifications within the spirit and scope of the present invention can be clearly understood by those skilled in the art, specific embodiments such as the detailed description and preferred embodiments of the present invention should be understood as being given by way of example only.

1 is a block diagram showing the configuration of an air conditioning system having an expander according to a first embodiment of the present invention.
2 is a block diagram showing the configuration of an air conditioning system having an expander according to a second embodiment of the present invention.
3 is a cross-sectional view showing a compressor used in the present invention. 3 shows a horizontal scroll type compressor.
4 is a block diagram showing a specific example of an air conditioning system having an expander according to a second embodiment of the present invention.
5 is a block diagram showing the configuration of an air conditioning system having an expander according to a first embodiment of the present invention.
6 is a block diagram showing the configuration of an air conditioning system having an expander according to a second embodiment of the present invention.

Hereinafter, exemplary embodiments disclosed in the present specification will be described in detail with reference to the accompanying drawings, but identical or similar elements are denoted by the same reference numerals regardless of reference numerals, and redundant descriptions thereof will be omitted. The suffixes "module" and "unit" for components used in the following description are given or used interchangeably in consideration of only the ease of preparation of the specification, and do not have meanings or roles that are distinguished from each other by themselves. In addition, in describing the embodiments disclosed in the present specification, when it is determined that a detailed description of related known technologies may obscure the subject matter of the embodiments disclosed in the present specification, the detailed description will be omitted. In addition, the accompanying drawings are for easy understanding of the embodiments disclosed in the present specification, and the technical idea disclosed in the present specification is not limited by the accompanying drawings, and all modifications included in the spirit and scope of the present invention It should be understood to include equivalents or substitutes.

Terms including ordinal numbers, such as first and second, may be used to describe various elements, but the elements are not limited by the terms. These terms are used only for the purpose of distinguishing one component from another component.

When a component is referred to as being "connected" or "connected" to another component, it is understood that it may be directly connected or connected to the other component, but other components may exist in the middle. Should be. On the other hand, when a component is referred to as being "directly connected" or "directly connected" to another component, it should be understood that there is no other component in the middle.

Singular expressions include plural expressions unless the context clearly indicates otherwise.

In the present application, terms such as "comprises" or "have" are intended to designate the presence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, but one or more other features. It is to be understood that the presence or addition of elements or numbers, steps, actions, components, parts, or combinations thereof, does not preclude in advance.

1 is a block diagram showing the configuration of an air conditioning system having an expander according to a first embodiment of the present invention.

First, referring to FIG. 1, a configuration of an air conditioning system having an expander according to a first embodiment of the present invention will be described.

The air conditioning system 1 comprises a compressor 2, a condenser 3, an expander 4 and an evaporator 5. A refrigerant pipe 6 through which a refrigerant flows is connected between the compressor 2, the condenser 3, the expander 4, and the evaporator 5. The compressor (2), condenser (3), expander (4), evaporator (5), and refrigerant pipe (6) are common components used in air conditioning systems. Therefore, a detailed description thereof will be omitted.

An oil separator 7 is provided between the compressor 2 and the condenser 3. The refrigerant discharged from the compressor 2 contains oil. The oil separator 7 separates oil from the refrigerant. The oil separated by the oil separator 7 is returned to the compressor 2 through the recovery pipe 72 and the refrigerant flows to the condenser 3.

An oil separator 8 is also provided between the expander 4 and the evaporator 5. An oil pump 9 is provided between the oil separator 8 and the expander 4. The oil pump 9 pumps the oil separated by the oil separator 9 to the expander 4.

As described above, in a general air conditioning system, the oil separator 8 and the oil pump 9 (or ejector) are used to lubricate the expander 4. Therefore, in such a general air conditioning system, a component for lubrication of the expander is added, so that the structure of the system may be complicated and the weight may be increased. In addition, installation costs, maintenance costs, etc. due to the installation of these components may increase.

2 is a block diagram showing the configuration of an air conditioning system having an expander according to a second embodiment of the present invention.

Hereinafter, an air conditioning system having an expander according to a second embodiment of the present invention will be described with reference to FIG. 2.

2, in the air conditioning system to which the compressor 2 and the expander 4 are applied, a path for injecting separated oil through the oil separator inside the compressor 2 into the inlet In of the expander 4 (hereinafter , The first oil path; 15), a path for injecting oil into the inlet (In) of the compressor (2) using an oil separator installed at the outlet (Out) of the expander (4) (hereinafter, referred to as the second oil). Path; 16) can be provided.

That is, the first oil path 15 may be provided between the oil outlet (Oil out) of the compressor (2) and the refrigerant inlet (In) of the expander 4, and the second oil path 16 is an expander (4). It may be provided between the oil outlet (Oil out) of) and the refrigerant inlet (In) of the compressor (2).

In this case, the first oil path 15 may be connected to the first refrigerant path 12 connected between the condenser 3 and the suction port In of the expander 4. That is, the first oil path 15 is connected to the first refrigerant path 12, so that the refrigerant flows along with the oil in the first refrigerant path 12, so that the refrigerant may flow into the inlet In of the expander 4. .

In addition, the second oil path 16 may be connected to a second refrigerant path 14 connected between the evaporator 5 and the suction port In of the compressor 2. That is, the second oil path 16 is connected to the second refrigerant path 14, so that the refrigerant flows along with the oil in the second refrigerant path 14, so that the refrigerant may flow into the suction port In of the compressor 2. .

3 is a cross-sectional view showing a compressor used in the present invention. 3 shows a horizontal scroll type compressor.

Referring to FIG. 3, such a horizontal scroll type compressor 2 includes a housing (casing) 210 having a sealed internal space, and components for compressing fluid may be installed in the housing 210. . That is, in the housing 210, a motor 220, a rotation shaft 230, a fixed scroll 250 and a revolving scroll 260 engaged with each other, and a frame 240 in which the rotation shaft 230 is installed may be included. .

The housing 210 for forming the sealed space may be formed in a horizontal cylinder shape. In the housing 210, an inlet 211 and an outlet 212 for entering and exiting the refrigerant may be formed.

In this case, the housing 210 may include a main housing 216 provided with a suction port 211 and a rear housing 215 provided with a discharge chamber 22. The frame 240 and the fixed scroll 250 may be installed between the main housing 216 and the rear housing 215.

A motor 220 that generates rotational force may be installed in the inner space of the housing 210. In addition, a rotation shaft 230 coupled to the rotor 221 of the motor 220 may be installed.

The rotation shaft 230 may be eccentrically coupled to the orbiting scroll 260. That is, the motor 220 may provide a rotational force for the orbiting scroll 260 to orbit through the rotation shaft 230.

A frame 240 may be installed on one side of the motor 220. The frame 240 may be formed of a material having high hardness as a main frame.

The frame 240 may provide a support structure in which the fixed scroll 250 and the orbiting scroll 260 can be installed. That is, the fixed scroll 250 may be coupled to the frame 240 to form the compressed space 21.

In this case, the housing 210 includes a discharge chamber 22 through which refrigerant gas is discharged from the compressed space 21, and the discharge port 212 is provided in the discharge chamber 2, and the refrigerant in the discharge chamber 22 May be discharged through the discharge port 212.

In the discharge chamber 22, the oil may be separated from the refrigerant through the oil separator 214, and in this case, the oil separated on the lower side may be sucked through the oil pickup and supplied to each rotating part.

In this case, as described with reference to FIG. 2, an oil outlet may be provided below the discharge chamber 22 in which the separated oil accumulates (see FIG. 4 ).

A separate inverter space (not shown) may be provided on the inlet 211 side of the housing 210, and an inverter unit may be located in this inverter space (not shown).

The motor 220 is installed in the inner space of the housing 210 to generate a rotational force, and a stator assembly including a stator 222 in which a winding is installed and an insulator for insulating the winding by being coupled to the stator 222 It may include a rotor 221 coupled to the stator assembly and rotating.

In this way, the motor 220 may have an internal rotor-like structure in which the stator 222 is located on the outer circumferential side of the rotor 221.

Meanwhile, a bearing 231 for sealing a compression space may be installed at one side of the frame 240 to fix the rotation shaft 230 so as to be rotatable. On the other hand, in some cases, the bearing 232 is also installed on the inner end side of the housing 210 so that the rotating shaft 230 can rotate smoothly.

Between the fixed scroll 250 and the frame 240, an orbiting scroll 260 may be installed that is coupled to the fixed scroll 250 and performs orbiting motion with respect to the fixed scroll 250.

The orbiting scroll 260 is connected to the rotation shaft 230 and is eccentrically coupled to the center of the rotation shaft 230 to implement a orbiting motion.

4 is a block diagram showing a specific example of an air conditioning system having an expander according to a second embodiment of the present invention.

First, referring to FIG. 4, the expander 4 may have a configuration similar to that of the compressor 2.

That is, the housing (casing) 410 of the expander 4, the motor 420, the rotation shaft 430, the fixed scroll 450 and the orbiting scroll 460 engaged with each other, and the frame 440 in which the rotation shaft 430 is installed. ) Is a housing (casing) 210 of the compressor 2, a motor 220, a rotating shaft 230, a fixed scroll 250 and a revolving scroll 260 meshing with each other, and a frame in which the rotating shaft 230 is installed ( 240).

Meanwhile, an outlet 411 of the expander 4 may be attached and installed outside the housing 415 on the opposite side of the fixed scroll 250.

In addition, the inlet 451 of the inflator 4 may be provided in the fixed scroll 250. In this way, the fixed scroll 250 of the expander 4 may constitute an outer housing.

The expander 4 may expand the refrigerant by the refrigerant flowing into the suction port 451 or a mixture of refrigerant and oil to convert the refrigerant into shaft power.

In addition, a detailed description of the configuration of the expander 4 may be equally applied to the configuration of the corresponding compressor 20. Therefore, redundant descriptions are omitted. However, the drive paths of the configuration may be opposite to each other. That is, the expander 4 may be operated by a refrigerant flowing into the suction port 451 or a mixture of refrigerant and oil.

Referring to FIG. 4, in an air conditioning system to which a compressor 2 and an expander 4 are applied, a path for injecting separated oil through an oil separator inside the compressor 2 to an inlet of the expander 4 (hereinafter , The first oil path; 15), a path for injecting oil to the inlet of the compressor 2 using an oil separator installed at the outlet of the expander 4 (hereinafter, referred to as the second oil Path; 16) can be formed.

That is, the first oil path 15 may be provided between the oil outlet of the compressor 2 and the refrigerant inlet of the expander 4, and the second oil path 16 is an expander 4 It may be provided between the oil outlet (Oil out) of) and the refrigerant inlet (Inlet) of the compressor (2).

In this case, the first oil path 15 may be connected to the first refrigerant path 12 connected between the condenser 3 and the inlet of the expander 4. That is, the first oil path 15 is connected to the first refrigerant path 12, so that the refrigerant flows together with the oil in the first refrigerant path 12, so that the refrigerant may flow into the inlet of the expander 4. .

In addition, the second oil path 16 may be connected to a second refrigerant path 14 connected between the evaporator 5 and an inlet of the compressor 2. That is, the second oil path 16 is connected to the second refrigerant path 14, so that the refrigerant flows together with the oil in the second refrigerant path 14, so that the refrigerant may flow into the inlet of the compressor 2 .

The first oil path 15 may be connected to a lower end of the discharge chamber 22 of the compressor 2, where the oil separated from the discharge chamber 22 of the compressor 2 descends.

In addition, the second oil path 16 may be connected to the lower end of the discharge chamber 42 of the expander 4 to which the oil separated from the discharge chamber 42 of the expander 4 descends.

In this case, an oil separator 414 for separating oil from the refrigerant may be provided in the discharge chamber 42 of the expander 4.

5 is a block diagram showing the configuration of an air conditioning system having an expander according to a first embodiment of the present invention. 6 is a block diagram showing the configuration of an air conditioning system having an expander according to a second embodiment of the present invention.

Hereinafter, a first embodiment and a second embodiment will be compared and described with reference to FIGS. 5 and 6.

According to the first embodiment shown in FIG. 5, an oil separator 7 is provided between the compressor 2 and the condenser 3. The refrigerant discharged from the compressor 2 contains oil. The oil separator 7 separates oil from the refrigerant. The oil separated by the oil separator 7 is returned to the compressor 2 through the recovery pipe 72 and the refrigerant flows to the condenser 3.

An oil separator 8 is also provided between the expander 4 and the evaporator 5. An oil pump 9 is provided between the oil separator 8 and the expander 4. The oil pump 9 pumps the oil separated by the oil separator 9 to the expander 4.

As described above, in a general air conditioning system, the oil separator 8 and the oil pump 9 (or ejector) are used to lubricate the expander 4.

On the other hand, according to the second embodiment shown in FIG. 6, in the air conditioning system to which the compressor 2 and the expander 4 are applied, the oil separated through the oil separator inside the compressor 2 is transferred to the inlet of the expander 4 ( In), the separated oil is injected into the compressor (2) inlet (In) using an oil separator installed at the outlet (Out) of the expander (4) and the path (hereinafter, referred to as the first oil path; 15). A path (hereinafter, referred to as a second oil path) 16 may be provided.

That is, the first oil path 15 may be provided between the oil outlet (Oil out) of the compressor (2) and the refrigerant inlet (In) of the expander 4, and the second oil path 16 is an expander (4). It may be provided between the oil outlet (Oil out) of) and the refrigerant inlet (In) of the compressor (2).

Accordingly, the present invention according to the second embodiment can have the following effects.

That is, it is possible to prevent a decrease in system efficiency due to oil accumulation in the evaporator 5 and the condenser 3.

In addition, in the path described above, using the pressure difference between the outlet of the compressor 2 and the condenser 3 and the pressure difference between the outlet of the expander 4 and the evaporator 5, a separate oil separator as described in the first embodiment. (8) and oil pump (9) may not be required. Thus, the overall system can be simplified and the manufacturing cost can be reduced.

Moreover, according to this simplified structure, the efficiency of the entire air conditioning system can be increased.

In addition, it is possible to remove the pressure reducing device for the oil circulation system inside the compressor (2). Accordingly, the manufacturing cost of the compressor 2 can be reduced.

Features, structures, effects, and the like described in the above embodiments are included in at least one embodiment of the present invention, and are not necessarily limited to only one embodiment. Furthermore, the features, structures, effects, and the like illustrated in each embodiment can be implemented by combining or modifying other embodiments by a person having ordinary knowledge in the field to which the embodiments belong. Therefore, contents related to such combinations and modifications should be construed as being included in the scope of the present invention.

In addition, although the embodiments have been described above, these are only examples and do not limit the present invention, and those of ordinary skill in the field to which the present invention belongs are illustrated above within the scope not departing from the essential characteristics of the present embodiment. It will be seen that various modifications and applications that are not available are possible. For example, each component specifically shown in the embodiment can be modified and implemented. And differences related to these modifications and applications should be construed as being included in the scope of the present invention defined in the appended claims.

2: compressor 3: condenser
4: expander 5: evaporator
12: first refrigerant path
14: second refrigerant path
15: first oil path
16: second oil path

Claims (10)

In the air conditioning system,
A compressor having a refrigerant suction port and a refrigerant discharge port, and the refrigerant discharge port is provided in a discharge chamber to compress the refrigerant;
A condenser for condensing and liquefying the high temperature and high pressure refrigerant discharged from the compressor;
An expander provided with a refrigerant suction port and a refrigerant discharge port, and the refrigerant discharge port is provided in a discharge chamber, which sucks and expands the refrigerant to convert it into axial power;
An evaporator for heat exchange by evaporating the liquid refrigerant expanded in the expander;
A first oil path connected between the discharge chamber of the compressor and the refrigerant inlet of the expander; And
And a second oil path connected between the discharge chamber of the expander and the refrigerant inlet of the compressor. The air conditioning system of claim 1, wherein the first oil path is connected to a first refrigerant path connected between the condenser and the inlet of the expander. The air conditioning system according to claim 1, wherein the second oil path is connected to a second refrigerant path connected between the evaporator and an inlet of the compressor. The air conditioning system according to claim 1, wherein the first oil path is connected to a lower end of the discharge chamber of the compressor through which oil separated from the discharge chamber of the compressor descends. The air conditioning system according to claim 1, wherein the second oil path is connected to a lower end of a discharge chamber of the expander through which oil separated from the discharge chamber of the expander descends. The air conditioning system of claim 5, wherein an oil separator for separating the oil from the refrigerant is provided in the discharge chamber of the expander. The method of claim 6, wherein the inflator,
A housing having an inlet and a discharge port of the refrigerant and forming an inner space;
A motor installed in the inner space of the housing to generate a rotational force and including a stator and a rotor rotating with respect to the stator;
A rotating shaft coupled to the rotor of the motor to rotate;
A rotating shaft coupled to the rotor and rotating;
A frame installed on one side of the motor to support the rotation shaft;
A fixed scroll coupled to the frame to form a compression space; And
And an orbiting scroll eccentrically coupled to the rotating shaft, located in the compression space, and coupled to the fixed scroll to perform orbital motion to compress fluid. The air conditioning system of claim 6, wherein the discharge chamber of the expander is installed outside the housing on the opposite side of the fixed scroll. The air conditioning system according to claim 6, wherein the inlet of the expander is provided in the fixed scroll. The air conditioning system according to claim 6, wherein the fixed scroll of the expander constitutes an outer housing.

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