KR101544880B1 - Freezing cycle of air conditioner for vehicle - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a refrigeration cycle of an air conditioner for a vehicle, and more particularly, to a refrigeration cycle for a vehicle air conditioner, and more particularly to a refrigeration cycle comprising a compressor, a condenser, an internal heat exchanger, an expansion valve and an evaporator, A part of the refrigerant is supplied to an evaporator and a part of the refrigerant is sucked into an ejector through an internal heat exchanger through a branch pipe so that refrigerant having a lower pressure and temperature than the refrigerant supplied to the evaporator by the suction action of the ejector is introduced into the internal heat exchanger The length of the internal heat exchanger can be reduced, and the temperature of the refrigerant introduced into the compressor can be reduced to improve the durability of the compressor, and the refrigerant flow rate And the expansion valve improves the cooling performance, Relates to a downstream-side refrigerant temperature, refrigerant cycle for a vehicle air conditioner, so that by sensing the pressure controlling the refrigerant flow rate to control the temperature of the refrigerant entering the compressor superheat of the evaporator is also easily possible to keep the titration of the group.

Refrigeration cycle, ejector, internal heat exchanger, branch pipe

Description

[0001] The present invention relates to a refrigeration cycle of an air conditioner for a vehicle,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a refrigeration cycle of an air conditioner for a vehicle, and more particularly, to a refrigeration cycle for a vehicle air conditioner, and more particularly to a refrigeration cycle comprising a compressor, a condenser, an internal heat exchanger, an expansion valve and an evaporator, A part of the refrigerant is supplied to an evaporator and a part of the refrigerant is sucked into an ejector through an internal heat exchanger through a branch pipe so that refrigerant having a lower pressure and temperature than the refrigerant supplied to the evaporator by the suction action of the ejector is introduced into the internal heat exchanger The length of the internal heat exchanger can be reduced, and the temperature of the refrigerant introduced into the compressor can be reduced to improve the durability of the compressor, and the refrigerant flow rate And the expansion valve improves the cooling performance, Relates to a downstream-side refrigerant temperature, refrigerant cycle for a vehicle air conditioner, so that by sensing the pressure controlling the refrigerant flow rate to control the temperature of the refrigerant entering the compressor superheat of the evaporator is also easily possible to keep the titration of the group.

Background Art [0002] A vehicle air conditioner is an automobile interior product installed for the purpose of enabling a driver to secure front and rear vision by removing air from the windshield during rainy or winter or by cooling or heating the interior of the automobile in the summer or winter season. Such an air conditioner usually has a heating system and a cooling system at the same time so that the outside air or the inside is selectively introduced to heat or cool the air and then air is blown into the interior of the automobile to cool,

1, a general refrigeration cycle of such an air conditioner is generally composed of a compressor 1 for compressing and sending refrigerant, a condenser 1 for condensing high-pressure refrigerant sent out from the compressor 1 An expansion valve 3 for condensing the refrigerant condensed in the condenser 2 and condensing the refrigerant condensed in the condenser 2 and a low pressure liquid refrigerant throttled by the expansion valve 3, And an evaporator 4 for cooling the air discharged to the room by the endothermic effect of the evaporation of the refrigerant by evaporating by heat exchange with the air is connected to the refrigerant pipe 5 and the following refrigerant circulation process is performed Thereby cooling the interior of the automobile.

When the cooling switch (not shown) of the automotive air conditioner is turned on, the compressor 1 sucks and compresses the low-temperature and low-pressure gaseous refrigerant while being driven by the power of the engine and supplies the gaseous refrigerant to the condenser 2 And the condenser 2 heat-exchanges the gaseous refrigerant with the outside air to condense into a high-temperature high-pressure liquid. The liquid refrigerant discharged from the condenser 2 in a high-temperature and high-pressure state rapidly expands due to the throttling action of the expansion valve 3 and is sent to the evaporator 4 in a low-temperature low-pressure humidified state, The blower (not shown) exchanges the refrigerant with the air blowing into the vehicle interior. The refrigerant evaporates in the evaporator 4 and is discharged to the low-temperature and low-pressure gas state. The refrigerant is again sucked into the compressor 1 to recycle the refrigeration cycle as described above. In the above-mentioned refrigerant circulation process, as described above, the air blown by the blower (not shown) is cooled by the latent heat of evaporation of the liquid refrigerant circulating in the evaporator 4 through the evaporator 4 And discharged into the inside of the vehicle in a cold state.

A receiver dryer (not shown) is provided between the condenser 2 and the expansion valve 3 to separate the refrigerant from the gas phase and the liquid phase so that only the liquid phase refrigerant can be supplied to the expansion valve 3 .

The cooling efficiency of the air conditioner that performs the cooling operation through the above-described refrigeration cycle is determined by various factors. Among them, the supercooling of the high-pressure refrigerant just before being throttled by the expansion valve 3, The degree of superheat of the low-pressure refrigerant discharged from the evaporator 4 influences the refrigerant fluidity, the pressure drop amount in the evaporator 4, the superheating region of the evaporator 4 (partial area on the refrigerant outlet side of the evaporator) and the volume efficiency of the compressor 1 Thereby significantly affecting the cooling efficiency of the air conditioner.

For example, if the supercooling degree of the refrigerant before the throttling is increased, the refrigerant flow is stabilized because the refrigerant flow is stabilized and the refrigerant pressure drop amount in the evaporator 4 is decreased, thereby increasing the cooling efficiency of the air conditioner, Consumption decreases. On the other hand, if the superheat degree of the low-pressure refrigerant discharged from the evaporator 4 is not properly maintained, the evaporator 4 having a relatively high temperature, which is set to completely evaporate the refrigerant to prevent the liquid refrigerant from flowing into the compressor 1 ) Of the air conditioner must be enlarged, so that the cooling performance of the air conditioner is lowered.

Accordingly, in general, when the supercooling degree of the refrigerant increases before the throttling and the superheat degree of the refrigerant discharged from the evaporator 4 is appropriately maintained, the cooling performance is improved.

In order to improve the cooling performance of the vehicle air conditioning system, the liquid refrigerant of high temperature and high pressure throttled by the expansion valve 3 is sub-cooled before flowing into the evaporator 4, and the superheat degree of the refrigerant discharged from the evaporator 4 Pressure liquid refrigerant flowing into the expansion valve 3 and the low-temperature and low-pressure gaseous refrigerant discharged from the evaporator 4, as shown in FIG. 2, An internal heat exchanger 6 for subcooling the high-temperature high-pressure liquid refrigerant before the throttle by mutual heat exchange and appropriately superheating the low-pressure refrigerant discharged from the evaporator 4 is mainly used.

The internal heat exchanger 6 exchanges heat between the high-temperature high-pressure liquid refrigerant before being throttled by the expansion valve 3 and the low-temperature low-pressure gaseous refrigerant discharged from the evaporator 4 to thereby exchange the refrigerant flowing into the evaporator 4 (Not shown) of the evaporator 4 which is set to be able to completely evaporate the refrigerant to prevent the inflow of the liquid refrigerant into the compressor 1, Time).

2, when the internal heat exchanger 6 is employed in the cooling system, since the amount of the refrigerant introduced into the evaporator 4 is reduced and the refrigerant pressure drop in the evaporator 4 is reduced, the evaporator 4 The refrigerant flowing into the compressor 1 can be superheated after being discharged from the evaporator 4, so that the temperature of the refrigerant is relatively high, so that the cooling performance of the air conditioner is deteriorated. The overheating region of the evaporator 4 as a factor can be reduced, and the cooling efficiency of the air conditioner can be greatly increased. As a result, the efficiency of the compressor 1, the condenser 2, and the evaporator 4 can be improved, contributing to the high efficiency and miniaturization of the air conditioner.

However, when the superheated refrigerant discharged from the evaporator 4 passes through the internal heat exchanger 6 to further heat exchange with the high temperature high pressure refrigerant discharged from the condenser 2, the temperature of the superheated refrigerant further rises, There is a problem that the durability of the compressor 1 is lowered by raising the temperature of the refrigerant flowing into the compressor 1 and the durability of the refrigerant pipe 5 connected to the compressor 1 is also lowered.

In addition, when the temperature of the refrigerant flowing into the compressor 1 rises more than necessary, the refrigerant flow rate due to the increase of the specific volume is decreased, thereby deteriorating the cooling performance.

The expansion valve 3 controls the refrigerant flow rate by sensing the temperature and the pressure of the refrigerant discharged from the evaporator 4. The expansion valve 3 controls the refrigerant flow rate of the refrigerant upstream of the internal heat exchanger 6 The refrigerant flow rate can not be controlled even if the refrigerant at the outlet side of the internal heat exchanger 6 directed to the compressor 1 is overheated and the refrigerant discharged from the internal heat exchanger 6 and flowing into the compressor 1 There is a problem that it is difficult to control the temperature.

In order to solve the above problems, an object of the present invention is to provide an ejector between an expansion valve and an evaporator in a refrigeration cycle comprising a compressor, a condenser, an internal heat exchanger, an expansion valve and an evaporator, And a part of the refrigerant is re-sucked into the ejector through an internal heat exchanger through a branch pipe, so that refrigerant having a lower pressure and temperature than the refrigerant supplied to the evaporator by the suction action of the ejector is circulated to the internal heat exchanger, The length of the internal heat exchanger can be reduced and the temperature of the refrigerant introduced into the compressor can be reduced to improve the durability of the compressor and increase the refrigerant flow rate, And the expansion valve controls the temperature of the refrigerant on the downstream side of the internal heat exchanger , By detecting the pressure controlling the refrigerant flow rate, so to provide a refrigeration cycle for a vehicle air conditioning evaporator superheat of easily controlling the coolant temperature be maintained properly flowing into the compressor.

According to an aspect of the present invention, there is provided a refrigerant compressor comprising: a compressor for sucking and compressing refrigerant; a condenser for condensing the refrigerant compressed in the compressor; an expansion valve for throttling the refrigerant condensed in the condenser; Wherein the refrigerant discharged from the expansion valve and the refrigerant flowing between the expansion valve and the compressor are connected to each other by a refrigerant pipe connected to the evaporator for evaporating the refrigerant from the expansion valve and the evaporator, An internal heat exchanger for exchanging heat between the refrigerant discharged from the condenser and the refrigerant sucked into the ejector is installed between the condenser and the expansion valve. .

An ejector is provided between an expansion valve and an evaporator in a refrigeration cycle composed of a compressor, a condenser, an internal heat exchanger, an expansion valve, and an evaporator. A part of the refrigerant discharged from the ejector is supplied to an evaporator, The refrigerant having a pressure and a temperature lower than that of the refrigerant flowing into the evaporator due to the suction action of the ejector is circulated to the internal heat exchanger and is supplied to the internal heat exchanger through the internal heat exchanger It is possible to obtain a larger amount of heat exchange, thereby reducing the size (length) of the internal heat exchanger and miniaturizing the refrigeration cycle.

Further, refrigerant having a lower pressure and temperature than the refrigerant flowing into the evaporator by the suction action of the ejector is re-sucked through the branch pipe and the suction portion, and mixed with the refrigerant discharged from the expansion valve and supplied to the evaporator, And at the same time, the refrigerant appropriately overheated in the evaporator flows into the compressor, so that the temperature of the refrigerant flowing into the compressor is lower than that of the conventional refrigeration cycle, so that the durability of the compressor and the durability of the refrigerant pipe are improved, The refrigerant flow rate due to the decrease is also increased, thereby improving the cooling performance.

The temperature of the refrigerant at the outlet side of the evaporator, which is downstream from the internal heat exchanger, is sensed by the expansion valve to control the flow rate of the refrigerant, so that the temperature of the refrigerant flowing into the compressor can be easily controlled and the superheating degree of the evaporator can be appropriately maintained.

Further, by connecting the branch pipe to the upper side of the center of the refrigerant pipe, the refrigerant flowing in the refrigerant pipe is prevented from being sucked into the suction portion of the ejector by its own weight.

By providing the expansion valve and the ejector in the engine room of the vehicle, the flow noise of the refrigerant discharged from the ejector is minimized.

Further, since the boosting function through the diffuser portion of the ejector can be utilized, the load of the compressor is reduced, and the efficiency of the air conditioner is improved.

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

FIG. 3 is a configuration diagram showing a refrigeration cycle of a vehicle air conditioner according to the present invention, FIG. 4 is a configuration diagram showing another embodiment of a refrigeration cycle of a vehicle air conditioner according to the present invention, FIG. 6 is a cross-sectional view showing an internal heat exchanger in a refrigeration cycle of a vehicle air conditioner according to the present invention. FIG.

As shown in the figure, the refrigeration cycle of the automotive air conditioner according to the present invention includes a compressor 10, a condenser 20, an internal heat exchanger 30, an expansion valve 40, an evaporator 60, 5, an ejector 50 is disposed between the expansion valve 40 and the evaporator 60 in a refrigeration cycle.

The compressor 10 sucks and compresses the low-temperature low-pressure gaseous refrigerant discharged from the evaporator 60 while receiving power from a power supply source (engine or motor, etc.) and compresses the gaseous refrigerant discharged from the condenser 60 into the high- (20).

The condenser 20 heat-exchanges the gaseous refrigerant of high temperature and high pressure discharged from the compressor 10 with the outside air, condenses it into a high-temperature high-pressure liquid, and discharges it to the expansion valve 40.

The expansion valve 40 rapidly expands the high-temperature and high-pressure liquid refrigerant discharged from the condenser 20 by the throttling action and sends it to the evaporator 60 in a low-temperature low-pressure humidified state.

The evaporator 60 evaporates the low-pressure liquid refrigerant throttled in the expansion valve 40 by exchanging heat with the air blown toward the interior of the vehicle, thereby cooling the air discharged into the room by an endothermic effect due to the latent heat of evaporation of the refrigerant .

Subsequently, the vapor-phase refrigerant vaporized in the evaporator 60 is sucked into the compressor 10 again to recycle the refrigeration cycle as described above.

In addition, in the refrigerant circulation process described above, cooling of the interior of the vehicle is performed by evaporation of the liquid refrigerant circulating in the evaporator 60 while the air blown by the blower (not shown) of the vehicle air conditioner passes through the evaporator 60 Is cooled by latent heat and is discharged into the inside of the vehicle in a cold state.

A receiver dryer (not shown) is provided between the condenser 20 and the expansion valve 40 to separate the refrigerant in the vapor phase and the liquid phase so that only the liquid refrigerant can be supplied to the expansion valve 40 .

The internal heat exchanger 30 is installed between the condenser 20 and the expansion valve 40 to cool the refrigerant discharged from the condenser 20 and the refrigerant discharged from the ejector 50, The refrigerant re-sucked into the heat exchanger 52 is heat-exchanged with each other. The internal heat exchanger 30 will be described below again.

The ejector 50 is installed between the expansion valve 40 and the evaporator 60 to cool the refrigerant discharged from the expansion valve 40 and the refrigerant flowing between the expansion valve 40 and the compressor 10. [ And the refrigerant is re-sucked from the refrigerant and supplied to the evaporator (60).

The ejector 50 includes a nozzle unit 51, a suction unit 52, and a diffuser unit 53,

The nozzle unit 51 is inserted into the inlet side of the ejector 50 to increase the flow speed of the refrigerant while reducing the pressure of the refrigerant discharged from the expansion valve 40.

That is, one end of the nozzle unit 51 is connected to the expansion valve 40 via a refrigerant pipe 5c and the other end extends a certain length into the ejector 50, and the inner flow path of the nozzle unit 51 And is expanded after shrinkage.

Accordingly, the low-temperature low-pressure refrigerant discharged from the expansion valve 40 is accelerated to the supersonic state while passing through the nozzle unit 51, and the pressure of the refrigerant is lowered due to the increased speed, Becomes lower than the pressure of the refrigerant at the outlet side of the ejector (50) sucked through the suction port (52).

The suction unit 52 is formed to communicate with the outer circumferential surface of the ejector 50 in which the nozzle unit 51 is located and is connected to the refrigerant pipe 50 connecting the ejector 50 and the evaporator 60 through a branch pipe 33. 5d.

A portion of the refrigerant at the outlet side of the ejector 50 is discharged to the ejector 50 through the branch pipe 33 and the suction portion 52 due to the pressure lowered by the increased speed of the refrigerant ejected from the nozzle portion 51. [ And is sucked in. At this time, the refrigerant passing through the nozzle unit 51 and the refrigerant sucked through the suction unit 52 start to be mixed with each other.

The branch pipe 33 is branched from the refrigerant pipe 5d connecting the ejector 50 and the evaporator 60 so that a part of the refrigerant discharged from the ejector 50 flows through the internal heat exchanger 30 And then sucked back to the suction portion 52 of the ejector 50.

That is, a part of the refrigerant discharged from the ejector 50 is supplied to the evaporator 60 through the refrigerant pipe 5d and a part of the refrigerant is branched through the branch pipe 33, passes through the internal heat exchanger 30, As shown in FIG.

The branched pipe 33 is formed to be smaller than the diameter of the refrigerant pipe 5d so that a flow rate smaller than the refrigerant flow rate flowing along the refrigerant pipe 5d is sucked into the suction portion 52 of the ejector 50 Lt; / RTI >

The branched pipe 33 is branched into the refrigerant pipe 5d in the shape of a letter "T" or "Y". At this time, the branch pipe 33 is connected to the refrigerant pipe 5d, The refrigerant pipe 5d may be connected to an upper portion of the refrigerant pipe 5d so as not to be sucked into the suction portion 52 of the ejector 50. [

4, the branch pipe 33 is branched from the refrigerant pipe 5e connecting the evaporator 60 and the compressor 10, and is connected to the refrigerant pipe 5e, May be sucked back to the suction part (52) of the ejector (50) through the internal heat exchanger (30), and the same effect can be obtained.

The diffuser portion 53 is formed to expand on the outlet side of the ejector 50 and mixes the refrigerant sprayed from the nozzle portion 51 and the refrigerant sucked through the suction portion 52 The pressure of the refrigerant is increased.

The diffuser unit 53 is connected to the evaporator 60 and the refrigerant pipe 5b to send the refrigerant boosted by the diffuser unit 53 to the evaporator 60. [

By providing the ejector 50 between the expansion valve 40 and the evaporator 60 as described above, the refrigerant discharged from the ejector 50 and re-sucked into the suction portion 52 through the branch pipe 33 And is utilized as a low-temperature-side heat exchange medium in the internal heat exchanger (30).

Therefore, the refrigerant at a lower pressure and temperature than that of the refrigerant supplied to the evaporator 60 is circulated to the internal heat exchanger 30 by the suction action of the ejector 50, so that the internal heat exchanger 30 It is possible to obtain a large amount of heat exchange and thereby to reduce the size (length) of the internal heat exchanger 30 and also to miniaturize the refrigeration cycle.

The refrigerant is again sucked through the branch pipe 33 and the suction unit 52 to be mixed with the refrigerant discharged from the expansion valve 40 at a lower pressure and temperature than the refrigerant supplied to the evaporator 60, So that the performance of the evaporator 60 can be sufficiently exerted. At the same time, since the refrigerant appropriately overheated by the evaporator 60 flows into the compressor 10, it flows into the compressor 10 more than the conventional refrigeration cycle The temperature of the refrigerant is decreased to improve the durability of the compressor 10 and the durability of the refrigerant pipe 5, and the refrigerant flow rate due to the reduction of the volume of the refrigerant is also increased, thereby improving the cooling performance.

The sensing unit 41 of the expansion valve 40 is installed to sense the temperature and pressure of the refrigerant at the outlet of the evaporator 60 (that is, between the evaporator and the compressor). That is, Since the refrigerant flow rate is controlled by sensing the temperature and pressure of the refrigerant at the outlet side of the evaporator 60 which is downstream of the evaporator 60 and the evaporator 60, 60 can be appropriately maintained.

Since the boosting function through the diffuser part 53 of the ejector 50 can be utilized, the load on the compressor 10 can be reduced, and the efficiency of the air conditioner can be improved.

In order to minimize the flow noise of the refrigerant discharged from the ejector 50, the expansion valve 40 and the ejector 50 are preferably installed in the engine room of the vehicle.

The inner heat exchanger 30 is connected to the outer circumferential surface of the inner pipe (branch pipe) 31 by a double pipe structure to connect the refrigerant flowing inside the inner pipe 31 and the outer pipe 32 And the refrigerant flowing through the inside of the heat exchanger (not shown).

Here, the inside of the inner tube 31 is filled with a low-temperature low-pressure (low-pressure) fluid, which is discharged from the ejector 50 (or the evaporator 60) and re-sucked into the suction portion 52 of the ejector 50 through the branch pipe 33 And the refrigerant of high temperature and high pressure discharged from the condenser 20 flows into the inside of the outer tube 32.

Temperature refrigerant discharged from the condenser 20 and flowing to the expansion valve 40 and the refrigerant discharged from the ejector 50 (or the evaporator 60) and discharged through the branch pipe 33 to the outside of the ejector 50 The temperature of the refrigerant supplied to the evaporator 60 is lower than that of the refrigerant supplied to the evaporator 60 due to the suction action of the ejector 50, Pressure refrigerant discharged from the condenser 20 so that the refrigerant flowing into the expansion valve 40 is further subcooled, whereby the refrigerant flow is reduced and the refrigerant flow is stabilized and the refrigerant in the evaporator 60 is increased.

A branch pipe 33 connecting the outlet side refrigerant pipe 5d of the ejector 50 (or the evaporator 60) to the suction portion 52 of the ejector 50 is used as the inner pipe 31 do.

In addition, a spiral portion 31a is formed in the longitudinal section of the inner tube 31 in the longitudinal direction.

The outer tube 32 is formed in the shape of a circular pipe and inserted into the outer side of the inner tube 31 and the length thereof is longer than the length of the spiral portion 31a of the inner tube 31.

The outer surface of the spiral portion 31a of the inner tube 31 is in close contact with the inner surface of the outer tube 32 so that the gap between the spiral portion 31a of the inner tube 31 and the outer tube 32 Three spiral flow paths 32b are formed, and the three spiral flow paths 32b do not communicate with each other independently of each other.

The outlet refrigerant pipe 5a of the condenser 20 and the inlet refrigerant pipe 5b of the expansion valve 40 are coupled to both ends of the outer tube 32, respectively.

In addition, the outer tube 32 is formed at both ends with an expanded tube portion 32a in which a portion to which the refrigerant pipes 5a and 5b are coupled is extended.

Both ends of the outer tube (32) are shaft-sealed and sealed with the outer circumferential surface of the inner tube (31) by welding or the like.

Hereinafter, the operation of the refrigeration cycle of the automotive air conditioner according to the present invention will be described with reference to FIG.

First, the gaseous refrigerant of high temperature and high pressure compressed and discharged from the compressor 10 flows into the condenser 20, and the gaseous refrigerant flowing into the condenser 20 is condensed through heat exchange with the outside air, Liquid phase refrigerant, and then flows into the outer tube 32 of the inner heat exchanger 30.

The high-temperature and high-pressure refrigerant introduced into the outer tube 32 of the internal heat exchanger 30 flows along the outlet branch pipe 33 (inner tube) of the ejector 50 during the flow through the outer tube 32 Exchanges heat with the refrigerant flowing at a low temperature and pressure, and then flows into the expansion valve (40) and is decompressed / expanded.

The refrigerant is decompressed and expanded again as it passes through the nozzle unit 51 of the ejector 50, and the refrigerant expands at a low pressure, The flow rate is increased.

The pressure of the refrigerant accelerated by the supersonic speed passing through the nozzle unit 51 becomes lower than the pressure of the refrigerant at the outlet side of the ejector 50 so that a part of the refrigerant at the outlet side of the ejector 50 passes through the branch pipe 33, (52).

At this time, the low-temperature low-pressure refrigerant re-sucked along the branch pipe (inner tube) 33 performs heat exchange with the high-temperature and high-pressure refrigerant flowing through the outer tube 32 of the internal heat exchanger 30, 50 to be sucked into the suction unit 52.

Subsequently, in the ejector 50, a portion of the refrigerant discharged from the expansion valve 40, which has passed through the nozzle portion 51, and a portion of refrigerant at the outlet of the ejector 50, which is sucked through the suction portion 52, The pressure of the refrigerant is increased while passing through the diffuser portion 53, and the refrigerant is discharged from the ejector 50.

The refrigerant that is boosted and discharged from the ejector 50 flows into the evaporator 60. The refrigerant flowing into the evaporator 60 is heat-exchanged with air blown toward the inside of the vehicle to evaporate, And the air blown into the passenger compartment by the endothermic function is cooled.

Then, the low-temperature low-pressure refrigerant discharged from the evaporator 60 flows into the compressor 10, and recirculates the refrigerating cycle as described above.

1 is a schematic view showing a general refrigeration cycle,

2 is a schematic view showing a case where an internal heat exchanger is installed in a general refrigeration cycle,

3 is a view showing a refrigeration cycle of a vehicle air conditioner according to the present invention.

4 is a configuration diagram showing another embodiment of the refrigeration cycle of the automotive air conditioner according to the present invention.

5 is a sectional view showing an ejector in a refrigeration cycle of a vehicle air conditioner according to the present invention,

6 is a cross-sectional view illustrating an internal heat exchanger in a refrigeration cycle of a vehicle air conditioner according to the present invention.

Description of the Related Art [0002]

10: compressor 20: condenser

30: internal heat exchanger 31: branch pipe (inner pipe)

32: outer tube 40: expansion valve

50: Ejector 51:

52: suction portion 53: diffuser portion

60: Evaporator

Claims (8)

A compressor 10 for sucking and compressing the refrigerant, a condenser 20 for condensing the refrigerant compressed in the compressor 10, an expansion valve 40 for throttling the refrigerant condensed in the condenser 20, And a refrigerant pipe (5) connected to an evaporator (60) for evaporating the refrigerant flowing in from the expansion valve (40) Between the expansion valve 40 and the evaporator 60 is mixed a refrigerant discharged from the expansion valve 40 and a part of the refrigerant re-inhaled from the refrigerant flowing between the expansion valve 40 and the compressor 10 And an ejector 50 for supplying the evaporator 60 to the evaporator 60, An internal heat exchanger 30 is installed between the condenser 20 and the expansion valve 40 to exchange heat between the refrigerant discharged from the condenser 20 and the refrigerant re-drawn into the ejector 50 Refrigeration cycle of car air conditioner. The method according to claim 1, The ejector 50 includes a nozzle unit 51 for increasing the flow speed of the refrigerant while reducing the pressure of the refrigerant discharged from the expansion valve 40 and a control unit 50 for controlling the flow rate of the refrigerant injected from the nozzle unit 51 (52) for re-sucking a part of the refrigerant flowing between the expansion valve (40) and the compressor (10), and a refrigerant suctioned from the refrigerant sprayed from the nozzle part (51) And a diffuser unit (53) for mixing the refrigerant and increasing the pressure of the refrigerant to discharge the refrigerant. The method according to claim 1, A branch pipe 33 is connected to the refrigerant pipe 5d for connecting the ejector 50 and the evaporator 60 to the ejector 50 so that a part of the refrigerant discharged from the ejector 50 is sucked back to the ejector 50 through the internal heat exchanger 30. [ And a refrigerating cycle of the vehicle air conditioner. The method according to claim 1, A branch pipe 33 is provided in the refrigerant pipe 5e for connecting the evaporator 60 and the compressor 10 so that the refrigerant discharged from the evaporator 60 is sucked back to the ejector 50 through the internal heat exchanger 30 Wherein the refrigerating cycle of the air conditioner of the vehicle is provided. The method according to claim 3 or 4, Wherein the branch pipe (33) is connected to the upper side of the center of the refrigerant pipe (5d) (5e). The method according to claim 3 or 4, The branched pipe 33 is formed so as to be smaller than the diameter of the refrigerant pipes 5d and 5e so that the flow rate smaller than the refrigerant flow rate flowing along the refrigerant pipes 5d and 5e is sucked back to the ejector 50 A refrigeration cycle of a car air conditioner characterized by. The method according to claim 1, Wherein the expansion valve (40) and the ejector (50) are installed in an engine room of a vehicle. The method according to claim 1, The internal heat exchanger 30 includes an inner tube 31 through which the refrigerant sucked by the ejector 50 flows and a second tube structure connected to the outer circumferential surface of the inner tube 31, And an outer tube (32) through which the discharged refrigerant flows.

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