KR20140123819A - Air Conditioner - Google Patents

Abstract

The present invention relates to an air conditioner capable of injecting a refrigerant into a compressor in both heating operation and cooling operation. An air conditioner according to an embodiment of the present invention includes: a compressor for compressing refrigerant; An outdoor heat exchanger installed outdoors for exchanging heat between the outdoor air and the refrigerant; An indoor heat exchanger installed in a room to exchange heat between indoor air and refrigerant; An operation switching unit that guides the refrigerant discharged from the compressor to the outdoor heat exchanger during a cooling operation and guides the refrigerant to the indoor heat exchanger during a heating operation; And an injection switching unit for guiding part of the refrigerant heat-exchanged in the outdoor heat exchanger during the cooling operation to be injected into the compressor and for guiding part of the refrigerant heat-exchanged in the indoor heat exchanger to be injected into the compressor during the heating operation.

Description

Air conditioner

BACKGROUND OF THE INVENTION 1. Field of the Invention [0002] The present invention relates to an air conditioner, and more particularly, to an air conditioner capable of injecting refrigerant into a compressor during both heating operation and cooling operation.

Generally, the air conditioner is a device for cooling or heating the room by using a refrigeration cycle including a compressor, an outdoor heat exchanger, an expansion valve, and an indoor heat exchanger. A radiator for cooling the room, and a radiator for heating the room. And a cooling / heating air conditioner for cooling or heating the room.

And a four-way valve for changing the flow path of the refrigerant compressed by the compressor according to the cooling operation and the heating operation when the air conditioner is composed of the air conditioner and the air conditioner. That is, the refrigerant compressed in the compressor during the cooling operation flows through the four-way valve to the outdoor heat exchanger, and the outdoor heat exchanger serves as the condenser. The refrigerant condensed in the outdoor heat exchanger is expanded in the expansion valve, and then flows into the indoor heat exchanger. At this time, the indoor heat exchanger acts as an evaporator, and the refrigerant evaporated in the indoor heat exchanger passes through the four-way valve and flows into the compressor.

Such an air conditioner improves the efficiency by injecting a part of the refrigerant condensed in the indoor heat exchanger into the compressor when the outdoor temperature is excessively lowered during the heating operation. Such injection may be required even in the cooling operation, and a structure capable of performing both the heating operation and the cooling operation in the air-conditioning combined air conditioner is required.

SUMMARY OF THE INVENTION An object of the present invention is to provide an air conditioner capable of injecting a refrigerant into a compressor during both a heating operation and a cooling operation.

The problems of the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

According to an aspect of the present invention, there is provided an air conditioner comprising: a compressor for compressing a refrigerant; An outdoor heat exchanger installed outdoors for exchanging heat between the outdoor air and the refrigerant; An indoor heat exchanger installed in a room to exchange heat between indoor air and refrigerant; An operation switching unit that guides the refrigerant discharged from the compressor to the outdoor heat exchanger during a cooling operation and guides the refrigerant to the indoor heat exchanger during a heating operation; And an injection switching unit for guiding part of the refrigerant heat-exchanged in the outdoor heat exchanger during the cooling operation to be injected into the compressor and for guiding part of the refrigerant heat-exchanged in the indoor heat exchanger to be injected into the compressor during the heating operation.

According to an aspect of the present invention, there is provided an air conditioner comprising: a compressor for compressing a refrigerant; An outdoor heat exchanger for condensing the refrigerant discharged from the compressor during the cooling operation and evaporating the refrigerant during the heating operation; An indoor heat exchanger for evaporating the refrigerant discharged from the compressor during the cooling operation and condensing the refrigerant during the heating operation; An indoor expansion valve for expanding a refrigerant flowing into the indoor heat exchanger during a cooling operation; An outdoor expansion valve for expanding the refrigerant flowing to the outdoor heat exchanger during heating operation; A first injection module for injecting a part of the refrigerant into the high pressure side of the compressor; A second injection module for injecting a part of the refrigerant into the low pressure side of the compressor; And connecting the outdoor expansion valve and the first injection module during cooling operation, connecting the second injection module and the indoor expansion valve, connecting the indoor expansion valve and the first injection module during a heating operation, And an injection switching unit connecting the injection module and the outdoor expansion valve.

The details of other embodiments are included in the detailed description and drawings.

The air conditioner of the present invention has one or more of the following effects.

First, there is an advantage that the refrigerant can be injected into the compressor not only in the heating operation but also in the cooling operation.

Second, the same injection module is used in heating operation and cooling operation to simplify the entire circuit structure.

Third, there is an advantage that the low-pressure refrigerant is injected into the compressor and the high-pressure refrigerant is injected into the high-pressure side to improve the efficiency.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the description of the claims.

FIG. 1 is a view illustrating a refrigerant flow in a cooling operation of an air conditioner according to an embodiment of the present invention. Referring to FIG.
FIG. 2 is a view showing a pressure-enthalpy diagram (hereinafter referred to as Ph diagram) during the cooling operation of the air conditioner shown in FIG.
FIG. 3 is a configuration diagram illustrating a refrigerant flow during a heating operation of the air conditioner according to an embodiment of the present invention.
FIG. 4 is a view showing a pressure-enthalpy diagram (hereinafter referred to as Ph diagram) during the heating operation of the air conditioner shown in FIG.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and the manner of achieving them, will be apparent from and elucidated with reference to the embodiments described hereinafter in conjunction with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Hereinafter, the present invention will be described with reference to the drawings for explaining an air conditioner according to embodiments of the present invention.

FIG. 1 is a view illustrating a refrigerant flow during a cooling operation of the air conditioner according to an embodiment of the present invention. FIG. 2 is a graph showing a pressure-enthalpy Diagram (hereinafter referred to as Ph diagram).

The air conditioner according to an embodiment of the present invention includes a compressor 110 for compressing a refrigerant, an outdoor heat exchanger 120 installed outside the room for exchanging heat between outdoor air and refrigerant, indoor air and refrigerant An operation switching unit 190 for guiding the refrigerant discharged from the compressor to the outdoor heat exchanger 120 during the cooling operation and guiding the refrigerant discharged to the indoor heat exchanger 130 during the heating operation, And a part of the refrigerant heat-exchanged in the outdoor heat exchanger 120 is injected into the compressor 110 and the part of the refrigerant heat-exchanged in the indoor heat exchanger 130 is injected into the compressor 110 during the heating operation. And includes a ring portion 160.

The compressor 110 compresses the introduced low-temperature low-pressure refrigerant into high-temperature high-pressure refrigerant. The compressor 110 may have various structures, and may be a reciprocating compressor using a cylinder and a piston, or a scroll compressor using a revolving scroll and a fixed scroll. In this embodiment, the compressor 110 is a scroll compressor. The compressors 110 may be provided in plurality according to the embodiment.

The compressor 110 includes a first inlet port 111 through which the refrigerant evaporated in the indoor heat exchanger 130 flows in the cooling operation or refrigerant evaporated in the outdoor heat exchanger 120 flows during the heating operation, A second inlet port 112 through which the relatively low pressure refrigerant expanded in the module 180 flows and a third inlet port 113 through which the relatively high pressure refrigerant evaporated and expanded in the first injection module 170 flows, And a discharge port 114 through which the compressed refrigerant is discharged.

The second inlet port 112 is formed on the low pressure side of the compression chamber where the refrigerant is compressed in the compressor 110 and the third inlet port 113 is formed on the high pressure side of the compression chamber of the compressor 110.

The refrigerant flowing into the first inlet port 111 is lower in pressure and temperature than the refrigerant flowing into the second inlet port 112 and the refrigerant flowing into the second inlet port 112 flows through the third inlet port 113, The pressure and the temperature are lower than those of the refrigerant flowing into the compressor. The refrigerant flowing into the third inlet port 113 is lower in pressure and temperature than the refrigerant discharged to the discharge port 114.

The compressor 110 compresses the refrigerant introduced into the first inlet port 111 in the compression chamber and merges with the refrigerant introduced into the second inlet port 112 formed on the low-pressure side of the compression chamber to compress the refrigerant. The compressor 110 compresses the combined refrigerant, joins with the refrigerant flowing into the third inlet port 113 formed on the high-pressure side of the compression chamber, compresses and compresses the combined refrigerant. The compressor (110) compresses the combined refrigerant and discharges it to the discharge port (114).

The operation switching unit 190 guides the refrigerant compressed by the compressor 110 to the outdoor heat exchanger 120 during the cooling operation and to the indoor heat exchanger 130 during the heating operation .

The operation switching unit 190 is connected to the first inlet port 111 and the discharge port 114 of the compressor 110 and is connected to the indoor heat exchanger 130 and the outdoor heat exchanger 120. The operation switching unit 190 connects the discharge port 114 of the compressor 110 and the outdoor heat exchanger 120 during the cooling operation and connects the indoor heat exchanger 130 and the first inlet port 111 of the compressor 110, Lt; / RTI > The operation switching unit 190 connects the discharge port 114 of the compressor 110 and the indoor heat exchanger 130 during the heating operation and connects the outdoor heat exchanger 120 and the first inlet port 111 of the compressor 110, Lt; / RTI >

The operation switching unit 190 may be implemented with various modules capable of connecting different flow paths. In the present embodiment, the operation switching unit 190 is a valve. According to the embodiment, the operation switching unit 190 may be implemented with various valves or a combination thereof such as a combination of two three-way valves.

The outdoor heat exchanger (120) is disposed in the outdoor space, and the refrigerant passing through the outdoor heat exchanger (120) performs heat exchange with the outdoor air. The outdoor heat exchanger 120 acts as a condenser for condensing the refrigerant during the cooling operation and serves as an evaporator for evaporating the refrigerant during the heating operation.

The outdoor heat exchanger (120) is connected to the operation switching unit (190) and the outdoor expansion valve (140). The refrigerant compressed by the compressor 110 during the cooling operation and passed through the discharge port 114 of the compressor 110 and the operation switching unit 190 is introduced into the outdoor heat exchanger 120 and then condensed to be supplied to the outdoor expansion valve 140, . The refrigerant expanded in the outdoor expansion valve (140) during the heating operation flows into the outdoor heat exchanger (120), evaporates and is discharged to the operation switching unit (190).

The outdoor expansion valve (140) is fully opened during cooling operation to allow the refrigerant to pass therethrough, and the opening degree of the outdoor expansion valve (140) is controlled during the heating operation to expand the refrigerant. The outdoor expansion valve 140 is connected to the outdoor heat exchanger 120 and the injection switching unit 160. The outdoor expansion valve (140) is provided between the outdoor heat exchanger (120) and the injection switching part (160).

The outdoor expansion valve (140) passes the refrigerant flowing from the outdoor heat exchanger (120) during the cooling operation and guides the refrigerant to the injection switching unit (160). The outdoor expansion valve (140) expands the refrigerant flowing from the injection switching unit (160) to the outdoor heat exchanger (120) during the heating operation.

The indoor heat exchanger (130) is disposed in the indoor space, and the refrigerant passing through the indoor heat exchanger (130) performs heat exchange with the indoor air. The indoor heat exchanger 130 functions as an evaporator for evaporating the refrigerant during the cooling operation and as a condenser for condensing the refrigerant during the heating operation.

The indoor heat exchanger (130) is connected to the operation switching unit (190) and the indoor expansion valve (150). The refrigerant expanded in the indoor expansion valve (150) flows into the indoor heat exchanger (130), is evaporated, and is discharged to the operation switching unit (190). The refrigerant compressed by the compressor 110 during the heating operation and passed through the discharge port 114 of the compressor 110 and the operation switching unit 190 flows into the indoor heat exchanger 130 and is condensed to be supplied to the indoor expansion valve 150, .

The opening degree of the indoor expansion valve (150) is regulated during the cooling operation, thereby expanding the refrigerant and allowing the refrigerant to pass therethrough during the heating operation. The indoor expansion valve (150) is connected to the indoor heat exchanger (130) and the injection switching unit (160). The indoor expansion valve (150) is provided between the indoor heat exchanger (130) and the injection switching part (160).

The indoor expansion valve (150) expands the refrigerant flowing from the injection switching unit (160) to the indoor heat exchanger (130) during the cooling operation. The indoor expansion valve (150) passes the refrigerant flowing from the indoor heat exchanger (130) during the heating operation and guides the refrigerant to the injection switching unit (160).

The injection switching unit 160 is a module for changing the flow path so that a part of the refrigerant condensed according to the cooling / heating switching of the operation switching unit 190 is injected into the compressor 110. The injection switching unit 160 guides a part of the refrigerant condensed in the outdoor heat exchanger 120 to be injected into the compressor 110 during the cooling operation and guides the other part to the indoor heat exchanger 130. The injection switching unit 160 guides part of the refrigerant condensed in the indoor heat exchanger 130 to the compressor 110 during the heating operation and guides the other part of the refrigerant to the outdoor heat exchanger 120.

The injection switching unit 160 may be realized by various modules that can connect different flow paths. In the present embodiment, the injection switching unit 160 is a four-way valve for switching the flow path. According to the embodiment, the injection switching portion 160 may be implemented with various valves or a combination thereof such as a combination of two three-way valves.

The injection switching unit 160 is connected to the outdoor expansion valve 140, the indoor expansion valve 150, the first injection module 170, and the second injection module 180. The injection switching unit 160 connects the outdoor expansion valve 140 and the first injection module 170 during the cooling operation and connects the second injection module 180 and the indoor expansion valve 150. The injection switching unit 160 connects the indoor expansion valve 150 and the first injection module 170 during the heating operation and connects the second injection module 180 and the outdoor expansion valve 140.

The first injection module 170 inflates a part of the refrigerant injected into the compressor 110 from the injection switching part 160 and injects the refrigerant into the high pressure side of the compressor 110. The first injection module 170 is connected to the injection switching unit 160, the third inlet port 113 of the compressor 110, and the second injection module 180.

The first injection module 170 guides a part of the refrigerant flowing from the injection switching part 160 to the third inlet port 113 of the compressor 110 and injects the refrigerant into the high pressure side of the compressor 110, 160 to the second injection module 180. The second injection module 180 is a part of the second injection module 180,

The first injection module 170 includes a first injection expansion valve 171 for expanding a part of the refrigerant flowing from the injection switching part 160 and a second part of the refrigerant flowing from the injection switching part 160, And a first injection heat exchanger (172) that undergoes heat exchange with the refrigerant expanded in the injection expansion valve (171) to undergo supercooling.

The first injection expansion valve 171 is connected to the injection switching part 160 and the first injection heat exchanger 172. The first injection expansion valve 171 expands a part of the refrigerant discharged and branched from the injection switching part 160 and guides it to the first injection heat exchanger 172. The first injection expansion valve 171 adjusts the opening degree so that the pressure of the refrigerant passing therethrough is equal to the high pressure side pressure of the compressor 110 to which the third inlet port 113 is connected.

The first injection heat exchanger 172 includes an injection switching section 160, a first injection expansion valve 171, a third inlet port 113 of the compressor 110, a second injection expansion valve 181, And is connected to the heat exchanger 182.

The first injection heat exchanger 172 exchanges a part of the refrigerant discharged from the injection switching part 160 with the refrigerant expanded in the first injection expansion valve 171. The first injection heat exchanger 172 guides the refrigerant expanded in the first injection expansion valve 171 and heat-exchanged in the first injection heat exchanger 172 to the high pressure side of the compressor 110.

A portion of the refrigerant flowing from the injection switching unit 160 is subjected to heat exchange in the first injection heat exchanger 172 and then to the second injection expansion valve 181 and the second injection heat exchanger 182 after being supercooled. The refrigerant expanded in the first injection expansion valve 171 is heat-exchanged in the first injection heat exchanger 172 and evaporated and then flows to the third inlet port 113 of the compressor 110 to be injected into the high pressure side of the compressor 110 do.

The second injection module 180 inflates a part of the refrigerant injected into the compressor 110 from the injection switching part 160 and injects the refrigerant into the low pressure side of the compressor 110. The second injection module 180 is connected to the first injection module 170, the second inlet port 112 of the compressor 110, and the injection switching unit 160.

The second injection module 180 guides part of the refrigerant flowing from the first injection module 170 to the second inlet port 112 of the compressor 110 and injects the refrigerant into the low pressure side of the compressor 110, And directs another portion of the refrigerant flowing from the module 170 to the injection switching portion 160.

The second injection module 180 includes a second injection expansion valve 181 for expanding a part of the refrigerant supercooled in the first injection heat exchanger 172 and a second injection expansion valve 182 for expanding a part of the refrigerant supercooled in the first injection heat exchanger 172, And a second injection heat exchanger 182 for performing a supercooling operation by exchanging a part of the refrigerant with the refrigerant expended in the second injection expansion valve 181.

The second injection expansion valve 181 is connected to the first injection heat exchanger 172 and the second injection heat exchanger 182. The second injection expansion valve 181 expands a part of the refrigerant discharged from the first injection heat exchanger 172 to the second injection heat exchanger 182. The second injection expansion valve 181 adjusts the opening degree so that the pressure of the refrigerant passing therethrough is equal to the low pressure side pressure of the compressor 110 to which the second inlet port 112 is connected.

The second injection heat exchanger 182 is connected to the first injection heat exchanger 172, the second injection expansion valve 181, the second inlet port 112 of the compressor 110 and the injection switching unit 160.

The second injection heat exchanger 182 exchanges a portion of the refrigerant discharged from the first injection heat exchanger 172 and branched from the second injection expansion valve 181 with the expanded refrigerant. The second injection heat exchanger 182 guides the refrigerant expanded in the second injection expansion valve 181 and heat-exchanged in the second injection heat exchanger 182 to the low pressure side of the compressor 110.

A portion of the refrigerant flowing from the first injection heat exchanger 172 is subjected to heat exchange in the second injection heat exchanger 182 and is supercooled and then flows to the injection switching unit 160. The refrigerant expanded in the second injection expansion valve 181 is heat-exchanged in the second injection heat exchanger 182 and evaporated and then flows to the second inlet port 112 of the compressor 110 to be injected into the low pressure side of the compressor 110. [ do.

At least one of the first injection module 170 and the second injection module 180 is not configured as an expansion valve and a heat exchanger but may be a gas-liquid separator for separating the gaseous refrigerant and the liquid phase refrigerant such that the gaseous refrigerant is injected.

When the first injection module 170 is a gas-liquid separator, the first injection module 170 separates the gaseous refrigerant from the refrigerant flowing from the injection switching part 160 and injects the gaseous refrigerant into the high-pressure side of the compressor 110, 2 injection module 180, as shown in FIG.

When the second injection module 180 is a gas-liquid separator, the second injection module 180 separates the gaseous refrigerant from the refrigerant flowing from the first injection module 170 and injects the gaseous refrigerant into the low-pressure side of the compressor 110, And guides it to the injection switching unit 160.

Hereinafter, the operation of the air conditioner in the cooling operation according to the embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG.

The refrigerant compressed in the compressor 110 is discharged from the discharge port 114 and flows to the operation switching unit 190. The refrigerant discharged from the discharge port 114 and flowing to the operation switching unit 190 passes through the point b. At this time, the refrigerant is in a state of high temperature and high pressure at point b as shown in FIG.

The operation switching unit 190 during the cooling operation connects the discharge port 114 of the compressor 110 and the outdoor heat exchanger 120 so that the refrigerant flowing into the operation switching unit 190 passes through the point i, (120). The refrigerant passing through the point i is maintained at a pressure compared to point b, but the temperature is slightly lowered.

The refrigerant flowing from the operation switching unit 190 to the outdoor heat exchanger 120 undergoes heat exchange with the outdoor air and is condensed. The refrigerant condensed in the outdoor heat exchanger (120) flows through the point h to the outdoor expansion valve (140). The refrigerant at the point h is significantly lowered in condensation temperature than the point i, and the pressure is maintained.

The refrigerant condensed in the outdoor heat exchanger (120) flows to the outdoor expansion valve (140). During the cooling operation, the outdoor expansion valve (140) is fully opened to pass the refrigerant and guide the refrigerant to the injection switching unit (160).

The injection switching unit 160 connects the outdoor expansion valve 140 and the first injection module 170 during the cooling operation so that the refrigerant flowing from the outdoor expansion valve 140 to the injection switching unit 160 flows through the first injection module (170).

A part of the refrigerant flowing from the injection switching part 160 flows through the point e to the first injection expansion valve 171 and the other part is guided to the first injection heat exchanger 172. The refrigerant passing through the point e is maintained at a pressure compared to the point h, but the temperature is slightly lowered.

The refrigerant flowing into the first injection expansion valve 171 expands and flows to the first injection heat exchanger 172 through the point j. The refrigerant passing through the point j is lowered in pressure while maintaining the temperature as compared with the point e. The pressure of the refrigerant at the point j is preferably equal to or substantially equal to the pressure at the high pressure side of the compression chamber of the compressor 110 to which the third inlet port 113 is connected. That is, the first injection expansion valve 171 adjusts the opening degree so that the pressure of the refrigerant passing therethrough is equal to the high pressure side pressure of the compressor 110 to which the third inlet port 113 is connected.

The refrigerant expanded in the first injection expansion valve 171 is guided to the first injection heat exchanger 172 and is heat-exchanged with the refrigerant discharged from the injection switching unit 160 and guided to the first injection heat exchanger 172 and evaporated . The refrigerant evaporated in the first injection heat exchanger 172 flows through the point k to the third inlet port 113 of the compressor 110. The refrigerant passing through point k maintains the pressure compared to point j, but the temperature rises.

The refrigerant that has flowed into the third inlet port 113 is injected into the high pressure side of the compressor 110, compressed, and then discharged to the discharge port 114.

A part of the refrigerant flowing from the injection switching unit 160 is subjected to heat exchange with the refrigerant expanded in the first injection expansion valve 171 in the first injection heat exchanger 172 to be supercooled. The refrigerant supercooled in the first injection heat exchanger (172) flows to the second injection module (180).

A part of the refrigerant flowing from the first injection heat exchanger 172 flows through the point f to the second injection expansion valve 181 and the other part is guided to the second injection heat exchanger 182. The refrigerant passing through the point f is kept at the pressure compared with the point e, but the temperature is lowered.

The refrigerant flowing to the second injection expansion valve 181 is expanded and flows to the second injection heat exchanger 182 through the point l. The refrigerant passing through the point l is kept at a temperature lower than the point f and the pressure is lowered. the pressure of the refrigerant at the point l is preferably equal to or substantially equal to the pressure at the low pressure side of the compression chamber of the compressor 110 to which the second inlet port 112 is connected. That is, the second injection expansion valve 181 adjusts the opening degree so that the pressure of the refrigerant passing therethrough is equal to the low pressure side pressure of the compressor 110 to which the second inlet port 112 is connected.

The refrigerant expanded in the second injection expansion valve 181 is guided to the second injection heat exchanger 182 and heat-exchanged with the refrigerant discharged from the first injection heat exchanger 172 and guided to the second injection heat exchanger 182 Evaporated. The refrigerant evaporated in the second injection heat exchanger 182 passes through the point m and flows to the second inlet port 112 of the compressor 110. The refrigerant passing through the point m is maintained at the pressure compared to point l, but the temperature is increased.

The refrigerant flowing into the second inlet port 112 is injected into the low pressure side of the compressor 110, compressed, and then discharged to the discharge port 114.

A part of the refrigerant flowing from the first injection heat exchanger 172 is subjected to heat exchange with the refrigerant expanded in the second injection expansion valve 181 in the second injection heat exchanger 182 to be supercooled. The refrigerant that has been overcooled in the second injection heat exchanger 182 passes through the point g and flows to the injection switching unit 160. The refrigerant passing through the point g is kept at the pressure compared to the point f but the temperature is lowered.

The injection switching unit 160 connects the second injection module 180 and the indoor expansion valve 150 during the cooling operation so that the refrigerant flowing from the second injection module 180 to the injection switching unit 160 is supplied to the indoor expansion valve 150).

The refrigerant expanded at the indoor expansion valve (150) expands and is guided to the indoor heat exchanger (130) through the point (d). The refrigerant passing through the point d is kept at a temperature lower than the point g and the pressure is lowered.

The refrigerant flowing into the indoor heat exchanger (130) is evaporated by indoor air heat exchange. The refrigerant evaporated in the indoor heat exchanger 130 passes through the point c and flows to the operation switching unit 190. The temperature of the refrigerant passing through the point c becomes higher than the point d, and the pressure is maintained.

Since the operation switching unit 190 connects the indoor heat exchanger 130 and the first inlet port 111 of the compressor 110 during the cooling operation, the refrigerant discharged from the indoor heat exchanger 130 to the operation switching unit 190, Passes through the point a and flows to the first inlet port 111 of the compressor 110. The refrigerant passing through point a maintains the pressure as compared with point c, but the temperature is slightly higher.

The refrigerant flowing to the first inlet port 111 is compressed by the compressor 110 and then discharged to the discharge port 114.

Hereinafter, the operation of the air conditioner in the heating operation according to the embodiment of the present invention will be described with reference to FIG. 3 and FIG.

FIG. 3 is a schematic view showing a refrigerant flow during a heating operation of the air conditioner according to an embodiment of the present invention, FIG. 4 is a graph showing a pressure-enthalpy curve in a heating operation of the air conditioner shown in FIG. Diagram (hereinafter referred to as Ph diagram).

The refrigerant compressed in the compressor 110 is discharged from the discharge port 114 and flows to the operation switching unit 190. The refrigerant discharged from the discharge port 114 and flowing to the operation switching unit 190 passes through the point b. At this time, the refrigerant is in a state of high temperature and high pressure at point b as shown in FIG.

During the heating operation, the operation switching unit 190 connects the discharge port 114 of the compressor 110 and the indoor heat exchanger 130, so that the refrigerant flowing into the operation switching unit 190 passes through the point c, (130). The refrigerant passing through point c maintains the pressure compared to point b, but the temperature is slightly lower.

The refrigerant flowing from the operation switching unit 190 to the indoor heat exchanger 130 is heat-exchanged with the indoor air and condensed. The refrigerant condensed in the indoor heat exchanger (130) passes through the point (d) and flows to the indoor expansion valve (150). Compared to point c, the refrigerant at point d is significantly lowered in temperature during condensation and the pressure is maintained.

The refrigerant condensed in the indoor heat exchanger (130) flows to the indoor expansion valve (150). During the heating operation, the outdoor expansion valve (140) is fully opened to pass the refrigerant and guide the refrigerant to the injection switching unit (160).

The injection switching unit 160 connects the indoor expansion valve 150 and the first injection module 170 during the heating operation so that the refrigerant flowing from the indoor expansion valve 150 to the injection switching unit 160 flows through the first injection module (170).

A part of the refrigerant flowing from the injection switching part 160 flows through the point e to the first injection expansion valve 171 and the other part is guided to the first injection heat exchanger 172. The refrigerant passing through point e maintains the pressure compared to point d but the temperature is slightly lower.

The refrigerant flowing into the first injection expansion valve 171 expands and flows to the first injection heat exchanger 172 through the point j. The refrigerant passing through the point j is lowered in pressure while maintaining the temperature as compared with the point e. The pressure of the refrigerant at the point j is preferably equal to or substantially equal to the pressure at the high pressure side of the compression chamber of the compressor 110 to which the third inlet port 113 is connected. That is, the first injection expansion valve 171 adjusts the opening degree so that the pressure of the refrigerant passing therethrough is equal to the high pressure side pressure of the compressor 110 to which the third inlet port 113 is connected.

The refrigerant expanded in the first injection expansion valve 171 is guided to the first injection heat exchanger 172 and is heat-exchanged with the refrigerant discharged from the injection switching unit 160 and guided to the first injection heat exchanger 172 and evaporated . The refrigerant evaporated in the first injection heat exchanger 172 flows through the point k to the third inlet port 113 of the compressor 110. The refrigerant passing through point k maintains the pressure compared to point j, but the temperature rises.

The refrigerant that has flowed into the third inlet port 113 is injected into the high pressure side of the compressor 110, compressed, and then discharged to the discharge port 114.

A part of the refrigerant flowing from the injection switching unit 160 is subjected to heat exchange with the refrigerant expanded in the first injection expansion valve 171 in the first injection heat exchanger 172 to be supercooled. The refrigerant supercooled in the first injection heat exchanger (172) flows to the second injection module (180).

A part of the refrigerant flowing from the first injection heat exchanger 172 flows through the point f to the second injection expansion valve 181 and the other part is guided to the second injection heat exchanger 182. The refrigerant passing through the point f is kept at the pressure compared with the point e, but the temperature is lowered.

The refrigerant flowing to the second injection expansion valve 181 is expanded and flows to the second injection heat exchanger 182 through the point l. The refrigerant passing through the point l is kept at a temperature lower than the point f and the pressure is lowered. the pressure of the refrigerant at the point l is preferably equal to or substantially equal to the pressure at the low pressure side of the compression chamber of the compressor 110 to which the second inlet port 112 is connected. That is, the second injection expansion valve 181 adjusts the opening degree so that the pressure of the refrigerant passing therethrough is equal to the low pressure side pressure of the compressor 110 to which the second inlet port 112 is connected.

The refrigerant expanded in the second injection expansion valve 181 is guided to the second injection heat exchanger 182 and heat-exchanged with the refrigerant discharged from the first injection heat exchanger 172 and guided to the second injection heat exchanger 182 Evaporated. The refrigerant evaporated in the second injection heat exchanger 182 passes through the point m and flows to the second inlet port 112 of the compressor 110. The refrigerant passing through the point m is maintained at the pressure compared to point l, but the temperature is increased.

The refrigerant flowing into the second inlet port 112 is injected into the low pressure side of the compressor 110, compressed, and then discharged to the discharge port 114.

A part of the refrigerant flowing from the first injection heat exchanger 172 is subjected to heat exchange with the refrigerant expanded in the second injection expansion valve 181 in the second injection heat exchanger 182 to be supercooled. The refrigerant that has been overcooled in the second injection heat exchanger 182 passes through the point g and flows to the injection switching unit 160. The refrigerant passing through the point g is kept at the pressure compared to the point f but the temperature is lowered.

The injection switching unit 160 connects the second injection module 180 and the outdoor expansion valve 140 during the heating operation so that the refrigerant flowing from the second injection module 180 to the injection switching unit 160 flows through the outdoor expansion valve 140.

The refrigerant expanded at the outdoor expansion valve (140) expands and is guided to the outdoor heat exchanger (120) through the point h. The refrigerant passing through the point h is kept at a temperature lower than the point g and the pressure is lowered.

The refrigerant flowing into the outdoor heat exchanger 120 is evaporated by performing outdoor air heat exchange. The refrigerant evaporated in the outdoor heat exchanger (120) flows through the point i to the operation switching unit (190). The refrigerant passing through the point i is significantly higher in temperature than the point h and the pressure is maintained.

The operation switching unit 190 connects the outdoor heat exchanger 120 and the first inlet port 111 of the compressor 110 during the heating operation and thus the refrigerant discharged from the outdoor heat exchanger 120 to the operation switching unit 190 Passes through the point a and flows to the first inlet port 111 of the compressor 110. The refrigerant passing through the point a maintains the pressure compared to the point i but the temperature is slightly higher.

The refrigerant flowing to the first inlet port 111 is compressed by the compressor 110 and then discharged to the discharge port 114.

The operation switching unit 190 connects the discharge port 114 of the compressor 110 and the outdoor heat exchanger 120 and connects the indoor heat exchanger 130 and the first inlet port The first injection module 170 is connected to the outdoor expansion valve 140 and the second injection module 180 is connected to the indoor expansion valve 150 So that a part of the refrigerant condensed in the outdoor heat exchanger 120 is injected into the high pressure side and the low pressure side of the compressor 110 during the cooling operation.

The operation switching unit 190 connects the discharge port 114 of the compressor 110 and the indoor heat exchanger 130 and connects the outdoor heat exchanger 120 and the first inlet port 111 of the compressor 110 The injection switching unit 160 connects the indoor expansion valve 150 and the first injection module 170 and connects the second injection module 180 and the outdoor expansion valve 140 to each other A part of the refrigerant condensed in the indoor heat exchanger 130 is injected into the high-pressure side and the low-pressure side of the compressor 110 during the heating operation.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It should be understood that various modifications may be made by those skilled in the art without departing from the spirit and scope of the present invention.

110: compressor
120: outdoor heat exchanger
130: Indoor heat exchanger
140: Outdoor expansion valve
150: Indoor expansion valve
160: Injection switching section
170: first injection module
171: First injection expansion valve
172: first injection heat exchanger
180: second injection module
181: a second injection expansion valve
182: Second Injection Heat Exchanger
190: Operation switching section

Claims (9)

A compressor for compressing the refrigerant;
An outdoor heat exchanger installed outdoors for exchanging heat between the outdoor air and the refrigerant;
An indoor heat exchanger installed in a room to exchange heat between indoor air and refrigerant;
An operation switching unit that guides the refrigerant discharged from the compressor to the outdoor heat exchanger during a cooling operation and guides the refrigerant to the indoor heat exchanger during a heating operation; And
And an injection switching unit for guiding a part of the refrigerant heat-exchanged in the outdoor heat exchanger during the cooling operation to be injected into the compressor and for guiding part of the refrigerant heat-exchanged in the indoor heat exchanger to be injected into the compressor during the heating operation, . The method according to claim 1,
The injection switching unit guides a part of the refrigerant heat-exchanged with the outdoor air in the outdoor heat exchanger during the cooling operation to the indoor heat exchanger and guides a part of the refrigerant heat-exchanged with the indoor air in the indoor heat exchanger to the outdoor heat exchanger during the heating operation Air conditioner. The method according to claim 1,
A first injection module for expanding a part of the refrigerant injected into the compressor from the injection switching part and injecting the refrigerant into the high pressure side of the compressor; And
Further comprising a second injection module that inflates a part of the refrigerant injected into the compressor from the injection switching part and injects the refrigerant into the low pressure side of the compressor. The method of claim 3,
The first injection module includes:
A first injection expansion valve for expanding a part of the refrigerant flowing from the injection switching part; And
And a first injection heat exchanger for undercooling another part of the refrigerant flowing from the injection switching part by exchanging heat with the refrigerant expanded in the first injection expansion valve,
The second injection module includes:
A second injection expansion valve for expanding a part of the refrigerant supercooled in the first injection heat exchanger; And
And a second injection heat exchanger for undercooling another part of the refrigerant supercooled in the first injection heat exchanger by heat exchange with the refrigerant expanded in the second injection expansion valve. 5. The method of claim 4,
The first injection heat exchanger is configured to introduce the refrigerant expanded in the first injection expansion valve and heat-exchanged in the first injection heat exchanger to the high pressure side of the compressor,
The second injection heat exchanger is configured to introduce the refrigerant expanded in the second injection expansion valve and heat-exchanged in the second injection heat exchanger to the low pressure side of the compressor,
Wherein the injection switching unit guides the refrigerant supercooled by the second injection heat exchanger to the indoor heat exchanger during the cooling operation and guides the refrigerant to the outdoor heat exchanger during the heating operation. The method according to claim 1,
An indoor expansion valve disposed between the indoor heat exchanger and the injection switching unit for expanding a refrigerant flowing from the injection switching unit to the indoor heat exchanger during a cooling operation; And
Further comprising an outdoor expansion valve disposed between the outdoor heat exchanger and the injection switching unit for expanding the refrigerant flowing from the injection switching unit to the outdoor heat exchanger during heating operation. A compressor for compressing the refrigerant;
An outdoor heat exchanger for condensing the refrigerant discharged from the compressor during the cooling operation and evaporating the refrigerant during the heating operation;
An indoor heat exchanger for evaporating the refrigerant discharged from the compressor during the cooling operation and condensing the refrigerant during the heating operation;
An indoor expansion valve for expanding a refrigerant flowing into the indoor heat exchanger during a cooling operation;
An outdoor expansion valve for expanding the refrigerant flowing to the outdoor heat exchanger during heating operation;
A first injection module for injecting a part of the refrigerant into the high pressure side of the compressor;
A second injection module for injecting a part of the refrigerant into the low pressure side of the compressor; And
The indoor expansion valve is connected to the first injection module during the cooling operation, and the second injection module is connected to the indoor expansion valve during the cooling operation, and the indoor expansion valve and the first injection module are connected during the heating operation, And an injection switching unit connecting the module and the outdoor expansion valve. 8. The method of claim 7,
The first injection module includes:
A first injection expansion valve for expanding a part of the refrigerant flowing from the injection switching part; And
And a first injection heat exchanger for undercooling another part of the refrigerant flowing from the injection switching part by exchanging heat with the refrigerant expanded in the first injection expansion valve,
The second injection module includes:
A second injection expansion valve for expanding a part of the refrigerant supercooled in the first injection heat exchanger; And
And a second injection heat exchanger for undercooling another part of the refrigerant supercooled in the first injection heat exchanger by heat exchange with the refrigerant expanded in the second injection expansion valve. 9. The method of claim 8,
The first injection heat exchanger is configured to introduce the refrigerant expanded in the first injection expansion valve and heat-exchanged in the first injection heat exchanger to the high pressure side of the compressor,
The second injection heat exchanger is configured to introduce the refrigerant expanded in the second injection expansion valve and heat-exchanged in the second injection heat exchanger to the low pressure side of the compressor,
Wherein the injection switching unit guides the refrigerant supercooled by the second injection heat exchanger to the indoor heat exchanger during the cooling operation and guides the refrigerant to the outdoor heat exchanger during the heating operation.

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