KR100853175B1 - Cooling and heating system for vehicle - Google Patents

Abstract

The present invention is to prevent the abnormal high pressure of the system in the heating system for cars using a hot gas heater system to improve the durability of each component and the system and at the same time to prevent the total heating capacity from falling, and to compress the refrigerant and And a condenser for condensing the refrigerant compressed by the compressor, at least one expansion valve for expanding the refrigerant, and an evaporator for exchanging the introduced refrigerant with air, wherein the refrigerant discharged from the compressor in the heating mode is partially selected. Circulates through the first refrigerant circuit circulated to pass back into the compressor after passing through the evaporator, and another part is branched by a predetermined amount before passing through the condenser before being introduced into the evaporator of the first refrigerant circuit. The second refrigerant circulation circuit circulated to enter the compressor Relates to a vehicle air conditioning system characterized in that the rock.

Description

Cooling and heating system for vehicle

1 to 4 are schematic configuration diagrams showing different embodiments of a vehicle air conditioning system according to the present invention, respectively.

Figure 5 is a graph showing the P-H curve of the vehicle air conditioning system according to Figures 1 to 4.

<Description of the symbols for the main parts of the drawings>

10: compressor 12: pressure sensor

20: condenser 30: evaporator

40: fluid separator 52: first expansion valve

54: second expansion edge 56: third expansion edge

58: fourth expansion edge 62: first opening and closing edge

64: second open and close 66: third open and close

68: fourth open and close 70: dispenser

100: control unit 110,210,310,410: first refrigerant circulation circuit

112,212,312,412: branch point 120,220,320,420: second refrigerant circulation circuit

130, 230, 330, 430: third refrigerant circulation circuit

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle air conditioning system, and more particularly, to a vehicle air conditioning system including a system using hot gas, which is a high temperature refrigerant discharged from a compressor, as an auxiliary heater.

In general, a vehicle is provided with an air conditioner, which is a cooling device, and a heater, which is a heating device, for air conditioning and heating inside a vehicle.

The air conditioner follows a refrigeration cycle using a refrigerant, and the refrigerant circulates the evaporator, the condenser and the compressor, converts the hot air introduced from the outside into the low temperature, and supplies the cold air to the vehicle interior. At this time, the condenser constituting the air conditioner converts the high-temperature, high-pressure gaseous refrigerant compressed by the compressor into a liquid refrigerant through heat exchange with air, and the evaporator exchanges the liquid refrigerant with high-temperature air to make it into a gaseous phase again. Absorbs heat from the air from outside.

On the other hand, the heater that is the heating device of the vehicle uses the coolant that cools the engine, and guides the coolant that cools the high-temperature engine to the heater core installed in the case of the air conditioner to draw external cool air flowing into the case. It is a hot water heater that heats and supplies it to the interior of a vehicle.

However, the above-described hot water heater has a problem that the heating capacity is insufficient when the engine is started at a start, that is, when the engine is not sufficiently heated and the temperature of the engine coolant is still low. In particular, such a lack of heating capacity is more severe when the external temperature is low. This is an inevitable limitation in hot water heaters that use engine cooled water as their heat source.

Therefore, various studies have been attempted to solve the fundamental problem of the conventional hot water heater, one of which is to operate the auxiliary heater heating cycle to assist the heating capacity of the hot water heater.

As a representative example of this auxiliary heater heating cycle, Japanese Patent Laid-Open No. 5-223357 introduces a high-temperature and high-pressure gas refrigerant discharged from a refrigerant discharge port of a compressor constituting a cooling cycle to an evaporator through an expansion valve, and air-conditioning the evaporator. A hot gas heater system is disclosed which is arranged in a casing of a device to heat the incoming air from outside to assist in heating the hot water heater.

The hot gas auxiliary heater system serves as an air conditioner by the existing refrigeration cycle in the summer, and serves as an auxiliary heater to increase the temperature of the cold outside air flowing from the blower unit in the winter. Since the hot gas operates only in the superheat degree region of the refrigerant, it is characterized by using the entrance and exit of heat by sensible heat without the process of condensation or evaporation of the refrigerant.

On the other hand, the hot gas heater system as described above is a component constituting the system when abnormal high pressure occurs in the entire system in all the hot gas operating area, such as varying external conditions, vehicle interior conditions and vehicle driving conditions such as the RPM change of the compressor It will cause fatal damage to them. Therefore, in a hot gas heater system, the technique of controlling such an abnormal high pressure is very important.                         

By the way, conventional hot gas auxiliary heater systems, including the system disclosed in the Japanese Patent Laid-Open Publication, lock the valve toward the condenser and induce the high temperature and high pressure refrigerant discharged from the compressor, that is, all the hot gas to the evaporator, thereby heating In order to further improve the effect, in order to solve the problem of abnormal high pressure as described above, a high pressure side control chamber was separately configured in a conventional variable pressure compressor equipped with a low pressure side control chamber.

However, the technology for preventing abnormal high pressure or low pressure by embedding the control chamber on the low pressure side and the high pressure side at the same time has many problems to be solved, and it is expensive because the structure of the compressor must be newly changed. In addition, this is not applicable to the stationary compressor currently used in most vehicles, there are many restrictions on its use.

The present invention has been made to solve the above problems, an object of the present invention is to provide a heating and cooling system for a vehicle that can prevent abnormal high pressure in the heating system for cars using a hot gas heater system.

Another object of the present invention is to provide a vehicle air conditioning system that can prevent the refrigerant passing through the condenser from passing through the evaporator in the heating and cooling system using the hot gas heater system to prevent the total heating ability from dropping. .

Still another object of the present invention is to provide a vehicle air conditioning system capable of improving the durability of each component constituting the system.

Still another object of the present invention is to improve the durability by improving the durability of the entire system, and to reduce the overall productivity and cost by controlling the pressure of the system while using the existing compressor as it is.

In order to achieve the above object, the present invention provides a compressor for compressing a refrigerant, a condenser for condensing the refrigerant compressed by the compressor, at least one expansion valve for expanding the refrigerant, and the introduced refrigerant to exchange heat with air. A first refrigerant circulation circuit circulated so that the refrigerant discharged from the compressor passes through the evaporator and then flows back into the compressor, and the refrigerant discharged from the compressor flows into the evaporator of the first refrigerant circulation circuit. It provides a heating system for a vehicle, comprising a second refrigerant circulation circuit for circulating before the predetermined amount is branched to pass through the condenser and then flows back into the compressor.

According to another feature of the invention, the amount of the refrigerant circulating in the second refrigerant circulation circuit may be less than 50% of the amount flowing into the branch point of the first refrigerant circulation circuit and the second refrigerant circulation circuit, preferably Can be 10% or more and 30% or less.

According to another feature of the invention, the distribution of the refrigerant to the first refrigerant circulation circuit and the second refrigerant circulation circuit is installed in each branched line of the first refrigerant circulation circuit and the second refrigerant circulation circuit, respectively, the evaporator And it may be made by an opening and closing valve for adjusting the amount of the refrigerant flowing into the condenser, or by a distributor installed at the branch point of the first refrigerant circulation circuit and the second refrigerant circulation circuit.

According to another feature of the invention, the line before the refrigerant flows into the compressor of the second refrigerant circulation circuit may be provided with an opening and closing valve to adjust the pressure of the compressor.

According to another feature of the present invention, an expansion valve may be provided in a line before the refrigerant of the second refrigerant circulation circuit flows into the compressor.

In order to achieve the above object, the present invention also provides a compressor for compressing a refrigerant, a condenser for condensing the refrigerant compressed by the compressor, at least one expansion valve for expanding the refrigerant, An evaporator for heat exchange, a first refrigerant circulation circuit circulated so that the refrigerant discharged from the compressor passes through the evaporator, and then flows back into the compressor, and the refrigerant discharged from the compressor flows into the evaporator of the first refrigerant circulation circuit The second refrigerant circulation circuit for circulating before passing through the condenser and flows back into the compressor, and the refrigerant passing through the condenser of the second refrigerant circulation circuit branched before passing into the compressor to pass through the evaporator And a third refrigerant circulation circuit which circulates to flow back into the compressor, and a mode switching unit. And a control unit for controlling the amount of refrigerant flowing into the first, second and third refrigerant circulation circuits. In the cooling mode, the refrigerant is circulated only to the third refrigerant circulation circuit in the cooling mode, and in the heating mode. The circulation of the refrigerant to the third refrigerant circulation circuit is interrupted by the control unit, and is distributed to the first refrigerant circulation circuit and the second refrigerant circulation circuit at a predetermined ratio, thereby providing a vehicle cooling and heating system. do.

Even in such a vehicle heating and cooling system, in the heating mode, the amount of refrigerant distributed to the second refrigerant circulation circuit may be less than 50% of the amount flowing into the branch point of the first refrigerant circulation circuit and the second refrigerant circulation circuit. Preferably, it may be made 10% or more and 30% or less.

In addition, the second refrigerant circulation circuit may be provided with an opening and closing valve electrically connected to the control unit in the line before the flow into the compressor to adjust the pressure of the compressor in the heating mode.

In addition, an expansion valve may be provided in a line before the refrigerant of the second refrigerant circulation circuit flows into the compressor.

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

<First Embodiment>

Figure 1 shows a schematic configuration of a vehicle air conditioning system according to an embodiment of the present invention.

As can be seen in the figure, a vehicle air conditioning system according to an embodiment of the present invention is a compressor 10 for compressing a refrigerant, a condenser 20 for condensing the compressed refrigerant, and at least one or more to expand the refrigerant Expansion valves (52) (54) (56) and an evaporator (30) for exchanging the refrigerant with air.

The compressor 10 is a drive pulley 11 is connected to the engine (not shown) to drive by using the power of the engine, any compressor, such as a fixed capacity or variable capacity compressor can be used.

The condenser 20 and the evaporator 30 may be provided with fans 22 and 32 for inducing the flow of air, respectively, and the evaporator 30 is an air conditioner that supplies low-temperature air to the room in a cooling mode. Used in the heating mode, it serves as an auxiliary heating device that complements the heating capability of the heater core (not shown).

The condenser 20 is usually installed in parallel with a radiator at the front of the vehicle to be positioned to increase contact with air as much as possible, and the evaporator 30 is a heater inside a case (not shown) of the air conditioner of the vehicle. It may be installed upstream of the core.

In the heating and cooling system configured as described above, an engine coolant that cools the engine in the heating mode is induced, and a heater core using the heat of the engine coolant is used as a main heat source, and the evaporator 30 is used to assist heating of the heater core. Will be used. At this time, the refrigerant compressed by the compressor 10 is directly introduced to the evaporator 30 without passing through the condenser 20 and used as a heat source, which is commonly referred to as a "hot gas auxiliary heater." Therefore, although not shown in the drawings in the vehicle air conditioning system according to the embodiments of the present invention to be described below, a heater core through which engine coolant flows is provided in the case (not shown) in which the evaporator 30 is installed. It may be set in the same air flow as 30).                     

According to a preferred embodiment of the present invention having the above components, as can be seen in Figure 1, the refrigerant discharged from the compressor 10 is branched before going to the condenser 20 and the evaporator 30, On the downstream side of each branched line from the branch point 112, a first opening and closing side 62 is provided on the evaporator 30 side and a second opening and closing side 64 on the condenser 20 side, and the refrigerant to flow through each branched line. Adjust the amount of.

On the other hand, the refrigerant branched from the branch point 112 of the first refrigerant circulation circuit 110 of which the first flow is returned to the compressor 10 through the first expansion side 52 and the evaporator 30 in sequence. The other first flow constitutes the second and third refrigerant circulation circuits 120 and 130 passing through the condenser 20. As shown in FIG. 1, the flow of the refrigerant passing through the condenser 20 is branched again after passing through the condenser 20, and a part of the second refrigerant circulation circuit 120 is directly bypassed to the compressor 10. ) And the other part circulates through the third refrigerant circulation circuit 130, which is returned to the compressor 10 via the third expansion side 56 and the evaporator 30. The distribution of the refrigerant to the second refrigerant circulation circuit 120 and the third refrigerant circulation circuit 130 is made by the third open and close sides 66 and the fourth open and close sides 68 installed on each line. At this time, at least one fluid separator 40 may be installed in the middle of the circuits.

In the cooling and heating system configured as described above, the opening and closing sides 62, 64, 66, 68 for adjusting the refrigerant distribution amount of each refrigerant circulation circuit is electrically connected to the control unit 100 of the control unit 100 It can be set as the solenoid valve which can open and close automatically by control. At this time, each valve may be controlled by the control unit 100 to control the opening and closing rate of the valve to adjust the amount of refrigerant flowing through the line.

In the above system, the amount of the refrigerant distributed by each of the opening and closing sides is made by the controller 100 as described above. The controller 100 includes a mode switching unit and a flow rate controller for controlling the amount of the refrigerant. . In addition, the control unit 100 is also connected to the pressure sensor 12 installed on the discharge side of the compressor 10 to properly adjust the opening and closing ratio of the opening and closing sides according to the change in the refrigerant pressure and mode of the discharge side of the compressor 10, 10) and an engine (not shown) to reflect elements such as the number of revolutions in the flow rate distribution of the refrigerant.

In the system, at least one expansion valve is installed, and the first expansion valve 52 and the evaporator 30 of the third refrigerant circulation circuit 130 installed in front of the evaporator 30 of the first refrigerant circulation circuit 110 are installed. The third expansion edge 56 is installed at the front end to expand the refrigerant flowing into the evaporator, and the second expansion edge 54 may be installed in the second refrigerant circulation circuit 120 that does not pass through the evaporator 30. .

Looking at the refrigerant flow of the vehicle air conditioning system having such a configuration, as follows.

First, when the system is adjusted to the cooling mode by the controller 100, the first opening and closing sides 62 and the third opening and closing sides 66 are closed so that the refrigerant is circulated only through the third refrigerant circulation circuit 130. At this time, the fourth opening and closing valve 68 is 100% open so that the refrigerant passing through the condenser 20 flows into the third expansion valve 56. Since the third expansion valve 56 expands the liquid refrigerant passing through the condenser 20, an orifice opening degree smaller than the expansion valve used in a conventional vehicle heating and cooling device may be used. As such, the refrigerant discharged from the compressor 10 in the cooling mode is introduced into the compressor 10 again through the condenser 20, the third expansion side 56, and the evaporator 30 to perform a general cooling cycle.

On the other hand, in the heating mode, the control unit 100 adjusts the opening / closing ratio of the first opening and closing sides 62 and the second opening and closing sides 64 so that the refrigerant is not only the first refrigerant circulation circuit 110 but also the second refrigerant circulation circuit ( A predetermined amount is also distributed to and flows through the 120, so that the hot gas discharged from the compressor performs a heating function through the first refrigerant circulation circuit 110, while the remaining hot gas is distributed to the condenser 20 to supply high pressure. To prevent the sudden rise of the. At this time, the fourth opening and closing valve 68 is preferably closed so that the refrigerant passing through the condenser 20 does not flow into the third refrigerant circulation circuit 130.

The vehicle air conditioning system according to an exemplary embodiment of the present invention shown in FIG. 1 protects the system from abnormal high pressure in a cooling and heating system employing a hot gas auxiliary heater system, and the refrigerant passing through the condenser in the heating mode has a cooling function. This is to prevent the heating efficiency from being lowered. To this end, the refrigerant flowing into the evaporator in the heating mode is dispersed in the condenser 20, and before the refrigerant passing through the condenser 20 enters the evaporator 30, the compressor ( 10) to bypass.

That is, in the heating mode, the condenser 20 from the first refrigerant circulation circuit 110 may be properly controlled by controlling the opening and closing ratio of the first opening and closing edge 62 and the second opening and closing edge 64 under the control of the controller 100. A predetermined amount is distributed to the side. This measures the discharge pressure of the refrigerant from the pressure sensor 12 installed on the discharge side of the compressor 10 and based on this, the control unit 100 directly to the evaporator 30 in consideration of the RPM or other external conditions of the compressor 100. By regulating the amount of refrigerant in the incoming hot gas system, the pressure in the system can be lowered to an appropriate level. At this time, the refrigerant flowing into the evaporator 30 through the first refrigerant circulation circuit 110 undergoes a throttling process at the first expansion side 52 before being introduced into the evaporator 30, and thus the evaporator 30 is lowered. Flows into). At this time, the first expansion edge 52 is to expand the refrigerant in a gaseous phase having a large specific volume, and the orifice opening is preferably larger than the third expansion edge 56 for expanding the liquid refrigerant.

Meanwhile, the fourth opening and closing valve 68 is closed so that the refrigerant passing through the condenser 20 does not flow into the third expansion valve 56 and the evaporator 30 and flows into the second refrigerant circulation circuit 120 to condense. By allowing the refrigerant having passed through 20 to flow directly into the compressor 10, the refrigerant passing through the condenser 20 does not flow into the evaporator 30 to perform a cooling function. At this time, the amount of the refrigerant passing through the condenser 20 and passing through the second refrigerant circulation circuit 120 may be controlled by the third open / close side 66 as shown in FIG. 1, and the second expanded side By expanding through 54, the liquid refrigerant may be prevented from flowing into the compressor as it is. In addition, the refrigerant passing through the second expansion side 54 may be introduced into the fluid separator 40 before being introduced into the compressor 10. Meanwhile, the liquid refrigerant, which is bypassed without entering the evaporator 30 through the second refrigerant circulation circuit 120 and expanded through the second expansion valve 54, passes through the evaporator 30 before entering the compressor 10. It is mixed with the refrigerant in a gaseous phase to lower the specific gravity of the liquid phase flowing into the compressor (10).

When the pressure detected by the pressure sensor 12 installed on the discharge side of the compressor 10 is equal to or less than the reference value in the above structure, the control unit 100 opens the third open / close side 66 by a predetermined ratio and flows in from the condenser 10. The expanded refrigerant is expanded to the second expansion side 54 and then sent to the infusion separator 40 to increase the amount of refrigerant circulating in the system to increase the pressure, on the contrary, if the detected pressure of the pressure sensor 12 is higher than the reference value, 100 reduces the amount of refrigerant circulating through the first refrigerant circulation circuit 110 by closing the third open / close valve 66 by a predetermined ratio, thereby reducing the pressure of the system.

The amount of distribution of the refrigerant distributed to the first refrigerant circulation circuit 110 and the second refrigerant circulation circuit 120 is distributed toward the condenser 20, that is, the amount distributed to the second refrigerant circulation circuit 120 side thereof. It is preferable to make it less than 50% of the total amount of refrigerant flowing into the branch point 112, and more preferably to be 10% or more and 30% or less. When the amount distributed to the second refrigerant circulation circuit 120 reaches 50% or more of the total amount of the refrigerant flowing into the branch point 112 of the first refrigerant circulation circuit 110 and the second refrigerant circulation circuit 120, it passes through the evaporator. Too much liquid refrigerant is introduced into the compressor by mixing with the refrigerant may affect the compressor, there is a risk of reducing the heating performance.

The refrigerant distribution amount to the second refrigerant circulation circuit 120 is such that when the compressor is low RPM, the refrigerant flows directly to the evaporator 30, that is, even if the amount of refrigerant circulating into the first refrigerant circulation circuit 110 is high, Since the amount of refrigerant that is circulated to the second refrigerant circulation circuit 120 may not be increased significantly, the amount of refrigerant flowing into the branch point 112 may be about 10%.

However, as the RPM value of the compressor 10 increases, the risk of increasing the high pressure increases, so the pressure sensor 12 installed at the outlet side of the compressor measures the pressure of the refrigerant discharged from the compressor 10 and transmits the pressure to the controller 100. The controller 100 adjusts the amount of refrigerant distribution between the first refrigerant circulation circuit 110 and the second refrigerant circulation circuit 120 based on the pressure. That is, as the pressure measured by the pressure sensor 13 becomes higher and higher, the amount of refrigerant circulated to the second refrigerant circulation circuit 120 gradually increases from 10%, 20%, and 30% of the amount of refrigerant flowing into the branch point 112. To go.

As such, the amount of refrigerant distributed to the condenser is relatively small compared to the amount of refrigerant flowing directly into the evaporator. As the refrigerant condenses and liquefies in the condenser, the specific volume may rapidly decrease, so that the amount of refrigerant may accumulate in the condenser 20. Even if the third open / close side 66 of the second refrigerant circulation circuit 120 is closed for a certain period of time, the circulation of the refrigerant is not impeded.

 When a part of hot gas, that is, hot gas, is introduced into the evaporator in the heating mode, a part of the gaseous refrigerant is converted into a saturated gas state, and the pressure of the hot gas in the system is lowered to prevent abnormal high pressure. It becomes possible. As the refrigerant passing through the condenser is not introduced into the evaporator, the heating performance can be prevented from being lowered.

FIG. 5 is a Ph diagram showing the state of the refrigerant in the heating mode, that is, at each stage of the heating system, in the above air conditioning system. Some of them pass through the first expansion edge 52 of the first refrigerant circulation circuit 110 and are adiabaticly expanded to decrease the pressure (point 3), causing heat exchange with the outside air through a heating process in the evaporator 30. The temperature is lowered (point 1) and flows back into the compressor 10, while the remaining part passes through the condenser 20 of the second refrigerant circulation circuit 120, and the temperature and pressure are reduced through the condensation process. It is in the state (point 4), expands while passing through the second expansion side (54), and is mixed with the refrigerant passed through the evaporator 30 to flow into the compressor.

Second Embodiment

Figure 2 shows another preferred embodiment according to the present invention, as in the first embodiment described above to prevent abnormal high pressure in the system and to reduce the deterioration of heating performance, the basic configuration is Similar to the case of one embodiment.

Also in this embodiment, the refrigerant discharged from the compressor 10 in the heating mode is refrigerant by the first opening and closing edge 62 and the second opening and closing edge 64 provided in each branched line downstream of the branch point 212. The distribution amount of is adjusted, and the fourth opening and closing valve 68 is closed so that the refrigerant passing through the condenser 20 flows only to the second refrigerant circulation circuit 220.

However, in the present exemplary embodiment, the fourth expansion side is one expansion side electrically connected to the control unit 100 with the expansion sides of the first refrigerant circulation circuit 210 and the third refrigerant circulation circuit 230 flowing into the evaporator 30. (58).

The fourth expansion valve 58 is to control the orifice opening ratio by the control unit 100 in the cooling mode and heating mode, and in the cooling mode in which the liquid refrigerant passing through the condenser 20 passes. Since the liquid refrigerant is expanded, the opening degree of the orifice is made small to expand the liquid having a relatively small volume so as to be about 5 to 20% of the total orifice size.In the heating mode, the hot gas, which is a hot refrigerant discharged from the compressor, is allowed to pass. The orifice opening should be at least 30% of the total orifice size. This is because in the heating mode, the refrigerant in the gaseous phase having a large volume is expanded, so that the orifice opening can be properly exhibited only when the opening degree is 30% or more of the total opening in the heating mode. In this case, when the orifice opening degree is small as in the cooling mode, the flow of the refrigerant is blocked by the choking phenomenon, in which the flow velocity of the refrigerant is the speed of sound.

Thus, by using the expansion valve which can change the orifice opening degree by the control unit, the same effect as in the first embodiment can be obtained in the heating mode and the cooling mode with a single expansion valve.

Third Embodiment

Figure 3 shows another preferred embodiment according to the present invention, which installs a distributor 70 at a branch point 312 branched to the condenser 20 side of the first refrigerant circulation circuit 310, this distributor 70 ) Is controlled by the control unit 100 to adjust the amount of refrigerant circulating in the first refrigerant circulation circuit 310 and the second refrigerant circulation circuit 320 in the heating mode.

The distributor 70 can be used as long as it has a three-way valve structure, and it is preferable that the distributor amount can be electronically controlled on the discharge side.                     

The hot gas distributor 70 blocks the amount circulated to the first refrigerant circulation circuit 310 in the cooling mode, supplies 100% of the refrigerant to the condenser 20, and adjusts the distribution ratio in the heating mode. Thus, less than 50%, preferably 10% or more and 30% or less of the total amount of the inflow to the condenser 20 is supplied.

In addition, the distributor 70 may be installed at branch points of the second refrigerant circulation circuit 320 and the third refrigerant circulation circuit 330 to replace the third open and close sides 66 and the fourth open and close sides 68. .

The third embodiment of the present invention according to FIG. 3 has the same function and operation as the first embodiment of the present invention according to FIG. 1 except for the hot gas distribution device 70, and thus description thereof will be omitted.

Fourth Embodiment

Figure 4 shows another preferred embodiment according to the present invention, which employs a distributor 70 applied in the third embodiment to the second embodiment of the present invention according to Figure 2. That is, a distributor having a 3-way valve structure at a branch point 412 of the second refrigerant circulation circuit 420 and the third refrigerant circulation circuit 430 passing through the first refrigerant circulation circuit 410 and the condenser 20 ( 70) and the amount of refrigerant flowing into the condenser 20 and the amount of refrigerant flowing into the fourth expansion side 58, that is, the first refrigerant circulation circuit 410 and the second refrigerant circulation circuit 420 in the heating mode. It is to adjust the amount of refrigerant distributed to.

In this case, the distributor 70 may be installed at the branch points of the second refrigerant circulation circuit 320 and the third refrigerant circulation circuit 330 to replace the third open and close sides 66 and the fourth open and close sides 68. have.

Since the refrigerant distribution amounts and the functions of the respective refrigerant circulation circuits have been described above, the description thereof will be omitted.

The vehicle air conditioning system according to the present invention as described above has the following effects.

First, the refrigeration cycle, that is, by utilizing the air conditioning cycle for auxiliary heating can exhibit a rapid heating capacity in case of cold.

Second, by circulating a part of the high-pressure refrigerant discharged from the compressor to the condenser can be solved the problem of abnormal high pressure generated in the hot gas auxiliary heating system.

Third, it is possible to prevent the problem that the heating performance is reduced by bypassing the refrigerant circulated to the condenser does not flow into the evaporator.

Fourth, by adjusting the amount of refrigerant accumulated in the condenser, it is possible to appropriately adjust the pressure of the system, thereby adjusting the overall heating capacity of the system.

Fifth, it is possible to improve the durability of the entire system by lowering the pressure on the discharge side of the compressor and to prevent the breakage of the components, thereby improving the design flexibility of the components.

Sixth, by expanding the refrigerant bypassed from the condenser to prevent the liquid refrigerant from flowing directly into the compressor, it is possible to prevent the durability and noise of the compressor.                     

Seventh, the simple configuration can improve the heating efficiency of the heating system for the vehicle, and can be applied to both fixed-capacity and variable-capacity compressors that are currently used in vehicles, thereby improving productivity.

Although the present invention has been described with reference to one embodiment shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent embodiments thereof are possible.

Therefore, the true scope of protection of the present invention should be defined only by the appended claims.

Claims (12)

A compressor for compressing the refrigerant; A condenser for condensing the refrigerant compressed by the compressor; At least one expansion valve for expanding the refrigerant; An evaporator for exchanging the introduced refrigerant with air; A first refrigerant circulation circuit circulated such that the refrigerant discharged from the compressor passes through the evaporator and then flows back into the compressor; And And a second refrigerant circulation circuit configured to circulate so that the refrigerant discharged from the compressor flows in a predetermined amount before passing into the evaporator of the first refrigerant circulation circuit and passes through the condenser and then flows back into the compressor. And the amount of the refrigerant circulating in the second refrigerant circulation circuit is less than 50% of the amount flowing into the branch points of the first refrigerant circulation circuit and the second refrigerant circulation circuit. delete The method of claim 1, The amount of the refrigerant circulating in the second refrigerant circulation circuit is 10% or more, 30% or less of the amount flowing into the branch point of the first refrigerant circulation circuit and the second refrigerant circulation circuit. delete delete delete delete A compressor for compressing the refrigerant; A condenser for condensing the refrigerant compressed by the compressor; At least one expansion valve for expanding the refrigerant; An evaporator for exchanging the introduced refrigerant with air; A first refrigerant circulation circuit circulated such that the refrigerant discharged from the compressor passes through the evaporator and then flows back into the compressor; A second refrigerant circulation circuit configured to circulate so that the refrigerant discharged from the compressor flows into the compressor after branching before passing into the evaporator of the first refrigerant circulation circuit and passing through the condenser; A third refrigerant circulation circuit configured to circulate before the refrigerant passing through the condenser of the second refrigerant circulation circuit flows into the compressor and passes through the evaporator and then flows back into the compressor; And And a controller configured to control the amount of refrigerant flowing into the first, second and third refrigerant circulation circuits, wherein the refrigerant is supplied only to the third refrigerant circulation circuit by the controller in the cooling mode. In the heating mode, the circulation of the refrigerant to the third refrigerant circulation circuit is interrupted by the controller, and the refrigerant is circulated at a predetermined ratio to the first refrigerant circulation circuit and the second refrigerant circulation circuit. Vehicle air conditioning system. The method of claim 8, And the amount of refrigerant distributed to the second refrigerant circulation circuit in the heating mode is less than 50% of the amount flowing into the branch point of the first refrigerant circulation circuit and the second refrigerant circulation circuit. The method of claim 9, The amount of refrigerant distributed to the second refrigerant circulation circuit in the heating mode is 10% or more, 30% or less of the amount flowing into the branch point of the first refrigerant circulation circuit and the second refrigerant circulation circuit. Air conditioning system. delete delete

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