KR101275071B1 - Expansion valve of air conditioning system for automotive vehicles - Google Patents

Abstract

The present invention relates to an expansion valve of a vehicle air conditioning system, and aims to increase or decrease the flow rate of the refrigerant without lowering the throttling efficiency.

In order to achieve the above object, the present invention provides an expansion valve of a vehicle air conditioning system that expands a refrigerant of a condenser at a low temperature and a low pressure and supplies it to an evaporator, the first and second throttle passages for throttling a refrigerant of a condenser, and an evaporator. And an opening amount adjusting device for adjusting the opening amounts of the first and second throttle passages according to the discharged coolant temperature, wherein the opening amount adjusting device is provided to each throttling passage to adjust the opening amount of each of the first and second throttling passages. Corresponding first and second valves; A temperature sensing chamber in which gas is encapsulated so as to expand or contract according to the refrigerant temperature at the outlet side of the evaporator; A diaphragm installed below the thermostat chamber so as to deform to a lower portion or an upper portion as the gas expands or contracts; The upper and lower deformation movements of the diaphragm are transmitted to the first and second valves so that the first and second valves adjust the opening amount while respectively moving the first and second throttle passages according to the temperature of the refrigerant discharged from the evaporator. To include a working rod.

Description

Expansion valve for vehicle air conditioning system {EXPANSION VALVE OF AIR CONDITIONING SYSTEM FOR AUTOMOTIVE VEHICLES}

1 is a cross-sectional view showing an expansion valve of a conventional vehicle air conditioning system,

Figure 2 is a t-s diagram showing the operating efficiency of the conventional air conditioning system is installed expansion valve,

3 is a cross-sectional view showing an expansion valve of a vehicle air conditioning system according to the present invention;

Figure 4 is a t-s diagram showing the operating efficiency of the air conditioning system is installed expansion valve of the present invention.

DESCRIPTION OF REFERENCE NUMERALS

1: condenser 8: evaporator

8a: outlet side 9 of the evaporator: compressor

30: valve body 32: high pressure refrigerant flow path

34: Introduction Euro 35: First Bridge Euro

36: second thoroughfare passage 37: discharge passage

38: low pressure refrigerant flow path 40: opening amount control device

42: first valve 44: second valve

45: first spring 46: second spring

50: thermal chamber 52: gas

60: diaphragm 70: working rod

72: body rod portion 74: first branch rod portion

75: second branch rod portion 80: expansion valve

The present invention relates to an expansion valve of a vehicle air conditioning system, and more particularly, when the flow rate of the refrigerant is to be increased or decreased by increasing or decreasing the opening amount of the throttle passage, a sufficient amount while minimizing the opening / closing ratio of the throttle passage. The expansion valve of the vehicle air conditioning system that can increase or decrease the refrigerant of the.

The car is equipped with an air conditioning system to regulate the air temperature in the room. As shown in FIG. 1, the air conditioning system includes an expansion valve 2 that expands the high pressure refrigerant discharged from the condenser 1 to low temperature and low pressure.

The expansion valve 2 is provided with a valve body 2a, and the high pressure refrigerant flow path 3 and the low pressure refrigerant flow path 5 are formed in the valve body 2a.

The high pressure refrigerant passage 3 discharges the introduction passage 3a for introducing the refrigerant of the condenser 1, the passage passage 3b for throttling the introduced refrigerant, and discharges the throttled refrigerant to the evaporator 8. It consists of a discharge flow path (3c).

In particular, the throttle passage 3b throttles the high-pressure refrigerant introduced into the introduction passage 3a to expand the low-temperature and low-pressure refrigerant. Therefore, the low-temperature and low-pressure refrigerant can be vaporized while passing through the evaporator 8, and the vaporized refrigerant can generate cold air while depriving the surrounding heat.

The low pressure refrigerant flow passage 5 has an inlet 5a connected to the evaporator 8 and an outlet 5b connected to the compressor 9. The low pressure refrigerant passage 5 introduces the low temperature and low pressure refrigerant discharged from the evaporator 8 and then discharges the introduced low temperature and low pressure refrigerant to the compressor 9.

The conventional expansion valve 2 includes an opening amount adjusting device 10 for adjusting the opening amount of the throttle passage 3b according to the temperature of the refrigerant discharged from the evaporator 8.

The opening amount adjustment device 10 includes a valve 12 disposed in the introduction flow passage 3a to open and close the throttle flow passage 3b, and a spring for elastically pressing the valve 12 in the direction of the throttle flow passage 3b ( 14).

The valve 12 is comprised of a spherical ball, and adjusts the opening amount of the throttle flow path 3b, moving about the throttle flow path 3b. The spring 14 is comprised by the coil spring and elastically presses the valve 12 to the throttle flow path 3b. In particular, elastic pressure is applied to the direction in which the throttle flow passage 3b is closed.

In addition, the opening degree adjusting device 10 includes a temperature reduction chamber 15 formed in the valve body 2a, a gas 15a enclosed in the temperature reduction chamber 15, and an expansion or contraction of the gas 15a. A diaphragm 17 for deforming downward movement and a push rod 18 for pressing the valve 12 while axially moving according to the up and down deformation movement of the diaphragm 17 are provided.

The temperature reduction chamber 15 is formed above the valve body 2a and is connected to the outlet side 8a of the evaporator 8 by a temperature transfer means. Thus, the temperature of the refrigerant discharged from the evaporator 8 is transmitted. Here, the temperature transfer means may be composed of a push rod 18. The push rod 18 transmits the refrigerant temperature of the evaporator 8 introduced into the low pressure refrigerant passage 5 to the upper temperature reduction chamber 15. Therefore, the refrigerant temperature of the outlet side 8a of the evaporator 8 is indirectly transmitted to the temperature reduction chamber 15.

The gas 15a has the same or similar properties as the refrigerant, and expands or contracts according to the refrigerant temperature of the evaporator 8 transferred to the temperature reduction chamber 15.

The diaphragm 17 deforms downward when the gas 15a expands, and deforms upward when the gas 15a contracts.

The push rod 18 extends from the bottom surface of the diaphragm 17 and passes through the low pressure refrigerant passage 5 and the discharge passage 3c of the high pressure refrigerant passage 3, and the push rod 18 penetrates through the throttle. After passing the flow path 3b, the valve 12 is configured to be pressurized. In particular, the valve 12 is pressed, but configured to press in the direction of opening the throttle flow passage 3b. The opening amount adjusting device 10 having such a configuration has a very small amount of refrigerant introduced into the evaporator 8 from the expansion valve 19, and when the refrigerant in the evaporator 8 is overheated, the superheated refrigerant temperature is transferred to the temperature reduction chamber 15. When the transferred and superheated refrigerant temperature is transferred to the temperature reduction chamber 15, the temperature of the temperature reduction chamber 15 is increased to expand the gas 15a therein.

When the gas 15a inside is expanded, the lower diaphragm 17 is deformed downward, and when the diaphragm 17 is deformed downward, the lower push rod 18 moves downward while the valve ( 12) is pressed to increase the opening amount of the throttle passage 3b.

Therefore, the amount of refrigerant passing through the throttle passage 3b is increased, and the increased refrigerant is introduced into the evaporator 8 to prevent overheating, and the refrigerant having been prevented from being overheated is introduced into the compressor 9 while being properly vaporized.

On the contrary, if the amount of refrigerant introduced from the expansion valve 19 to the evaporator 8 increases and the refrigerant of the evaporator 8 is excessively depleted, the desensitized refrigerant temperature is transmitted to the temperature reduction chamber 15, and the desensitized refrigerant temperature is reduced. When delivered to the greenhouse 15, the temperature of the temperature reduction chamber 15 decreases, and the gas 15a inside contracts.

When the internal gas 15a is contracted, the lower diaphragm 17 is deformed to the upper side. If the diaphragm 17 is deformed to the upper side, the lower push rod 18 moves upward and the valve 12 moves upward. ) Is released to reduce the opening amount of the throttle flow passage (3b).

Accordingly, the amount of refrigerant passing through the throttle passage 3b is reduced, and the reduced refrigerant is introduced into the evaporator 8 to prevent thermal phenomenon, and the refrigerant having been prevented from being introduced into the compressor 9 is properly vaporized.

However, since the conventional expansion valve has a structure in which the opening amount of the throttle passage 3b is increased when the refrigerant in the evaporator 8 is overheated, the throttling efficiency of the refrigerant increases as the opening amount of the throttle passage 3b increases. There is a disadvantage in that it is sharply lowered, and there is a problem in that the cooling performance of the evaporator 8 is lowered due to this disadvantage.

That is, in order to increase the cooling performance of the evaporator 8, it is important to lower the refrigerant pressure D by increasing the expansion amount CD of the refrigerant as shown in the ts diagram of FIG. In order to lower (D), it is important to increase the throttling efficiency of the refrigerant by reducing the opening amount of the throttle passage 3b, as shown in FIG.

However, the conventional expansion valve 19 has a structure in which the opening amount of the throttle passage 3b increases in proportion to the amount of the opening of the throttle passage 3b when the refrigerant of the evaporator 8 is overheated. There is a disadvantage that the throttling efficiency of the refrigerant is sharply lowered, and there is a problem that the cooling performance of the evaporator 8 is sharply lowered due to this disadvantage.

In particular, when the degree of overheating of the refrigerant is severe, the opening amount of the throttle flow passage 3b must be further increased in proportion to this, and thus the throttling efficiency of the refrigerant is further lowered, and the cooling performance of the evaporator 8 is further reduced due to the reduced throttling efficiency. There is a problem of deterioration.

As a result, since the cooling performance of the evaporator 8 is lowered, there is a problem that the cooling efficiency of the room is lowered as the air supplied to the interior of the vehicle is not sufficiently cooled and the air supplied to the interior is not sufficiently cooled, Due to these problems, there is a problem in that sufficient cooling effect cannot be expected in the summer when the temperature is very high.

In addition, since the expansion valve of the conventional expansion valve reduces the opening amount of the throttle passage 3b in proportion to this when the refrigerant discharged from the evaporator 8 is excessively reduced, the opening amount of the throttle passage 3b can be reduced. At the time, there is a disadvantage that the flow rate of the refrigerant supplied to the evaporator 8 is sharply reduced, and there is also a problem that the refrigerant of the evaporator 8 is overheated because of this disadvantage.

The present invention has been made to solve the above-mentioned conventional problems, the object is, when the refrigerant in the evaporator is overheated, a sufficient amount of refrigerant required to solve the refrigerant overheating while minimizing the increase in the opening degree of the throttle passage It is possible to provide an expansion valve of a vehicle air conditioning system that can prevent the reduction of the throttling efficiency of the refrigerant due to the increase in the opening amount of the throttle flow passage and at the same time eliminate the refrigerant overheating of the evaporator.

Another object of the present invention is to prevent a rapid decrease in the throttling efficiency of the refrigerant when the refrigerant of the evaporator is overheated, thereby preventing the cooling performance of the evaporator from rapidly deteriorating when the refrigerant of the evaporator is overheated. The present invention provides an expansion valve for a vehicle air conditioning system.

Still another object of the present invention is to reduce the thermal deterioration rate of the duct flow path by minimizing the reduction in the opening degree of the throttle flow path when the refrigerant of the evaporator is excessively reduced, thereby reducing the refrigerant thermal phenomenon of the evaporator. The present invention provides an expansion valve for a vehicle air conditioning system that can solve the problem and prevent overheating of the evaporator refrigerant caused by the rapid decrease in the opening amount of the throttle passage.

In order to achieve the above object, the expansion valve of the vehicle air conditioning system of the present invention, in the expansion valve of the vehicle air conditioning system for expanding the refrigerant of the condenser at low temperature and low pressure to supply to the evaporator, it is to throttle the refrigerant introduced from the condenser And an opening amount adjusting device for adjusting the opening amounts of the first and second drawing passages according to the temperatures of the first and second drawing passages and the refrigerant discharged from the evaporator. First and second valves disposed corresponding to each of the throttling passages so as to adjust respective opening amounts of the first and second throttle passages; A temperature reduction chamber in which a gas which expands or contracts according to a refrigerant temperature at an outlet side of the evaporator is sealed; A diaphragm installed below the thermostat chamber so as to be deformed to a lower portion or an upper portion according to expansion or contraction of the gas; The first and second valves move the upper and lower deformation movements of the diaphragm so as to adjust the opening amount while the first and second valves respectively move with respect to the temperature of the refrigerant discharged from the evaporator. And an actuating rod for transmitting to the second valve.

Hereinafter, a preferred embodiment of an expansion valve of a vehicle air conditioning system according to the present invention will be described in detail with reference to the accompanying drawings.

Referring to FIG. 3, the expansion valve of the present invention includes a valve body 30, and a high pressure refrigerant flow path 32 is formed in the valve body 30.

The high pressure refrigerant passage 32 includes an introduction passage 34 for introducing refrigerant of the condenser 1, first and second throttle passages 35 and 36 for throttling the introduced refrigerant, and first and second throttles. It consists of a discharge flow path 37 for discharging the refrigerant condensed in the flow path (35, 36) to the evaporator (8).

In particular, the first and second throttle passages 35 and 36 are formed side by side at intervals, and throttle the high-pressure refrigerant introduced into the introduction passage 34. Therefore, the refrigerant flowing from the introduction passage 34 to the discharge passage 37 is expanded to a low temperature and low pressure refrigerant.

Here, the first and second throttle passages 35 and 36 have a structure in which the refrigerant in the introduction passage 34 is throttled at two locations at the same time, so that the refrigerant having a sufficient flow rate can be throttled. Therefore, it is possible to supply the refrigerant with sufficient flow rate to the evaporator 8.

Meanwhile, in the detailed description of the present invention and in FIG. 3, the throttling flow paths for throttling the refrigerant are composed of two first and second throttle flow paths 35 and 36, but in some cases, three or four or more. It can also be configured as.

Referring again to FIG. 3, the expansion valve of the present invention includes a low pressure refrigerant passage 38 formed in the valve body 30.

The low pressure refrigerant flow path 38 has an inlet 38a connected to the evaporator 8 and an outlet 38b connected to the compressor 9. The low pressure refrigerant passage 38 introduces the low temperature and low pressure refrigerant discharged from the evaporator 8 and then discharges the introduced low temperature and low pressure refrigerant to the compressor 9.

In addition, the expansion valve of the present invention includes an opening amount adjusting device 40 for adjusting the opening amounts of the first and second throttle passages 35 and 36 according to the temperature of the refrigerant discharged from the evaporator 8.

The opening amount adjusting device 40 is introduced to open and close the first valve 42 and the second throttle passage 36 disposed in the introduction passage 34 so as to open and close the first throttle passage 35. The second valve 44 disposed in the flow path 34, the first spring 45 for elastically pressing the first valve 42 in the direction of the first throttle flow passage 35, and the second valve 44 A second spring 46 is elastically pressurized in the direction of the two throttle flow passages 36.

The first and second valves 42 and 44 are constituted by spherical balls, and the first and second throttle passages are moved with respect to the first and second throttle passages 35 and 36 respectively corresponding thereto. Adjust the opening amount of (35, 36).

The first and second springs 45 and 46 are constituted by coil springs, and the first and second valves 42 and 44 corresponding to the first and second springs 45 and 46 are respectively directed in the directions of the first and second throttle flow paths 35 and 36, respectively. Pressurize elastically. In particular, the first and second throttle passage 35, 36 is elastically pressed in the direction of closing. Thus, the first and second valves 42 and 44 can each reduce the amount of opening of the first and second throttle passages 35 and 36.

On the other hand, the valves 42 and 44, if the number of the throttle flow path is three or more, the number of the corresponding should be increased, of course.

In addition, the opening degree adjusting device 40 is formed by the expansion or contraction of the temperature reduction chamber 50 formed in the valve body 30, the gas 52 enclosed in the temperature reduction chamber 50, and the gas 52. Diaphragm (60) for lower deformation movement, and the operating rod (70) for transmitting the upper and lower deformation movement of the diaphragm (60) to the first and second valves (42, 44).

The temperature reduction chamber 50 is formed above the valve body 30 and is connected to the outlet side 8a of the evaporator 8 by a temperature transfer means. Thus, the temperature of the refrigerant discharged from the evaporator 8 is transmitted. Here, the temperature transmission means, may be composed of a working rod (70). The operation rod 70 transmits the refrigerant temperature of the evaporator 8 introduced into the low pressure refrigerant passage 38 to the upper temperature reduction chamber 50. Therefore, the refrigerant temperature of the outlet side 8a of the evaporator 8 is indirectly transmitted to the temperature reduction chamber 50.

The gas 52 is the same as or similar to the refrigerant, and expands or contracts according to the refrigerant temperature of the evaporator 8 delivered to the temperature reduction chamber 50. In particular, if the refrigerant temperature of the evaporator 8 is overheated, it expands rapidly, and if the refrigerant temperature of the evaporator 8 is too thermally depressed, it contracts rapidly.

The diaphragm 60 deforms downward when the gas 52 expands, and deforms upward when the gas 52 contracts.

The actuating rod 70 is composed of a body rod portion 72 and first and second branch rod portions 74 and 75 which are branched at intervals from the ends of the body rod portion 72.

The body rod portion 72 extends from the bottom surface of the diaphragm 60 and passes through the low pressure refrigerant passage 38 and the discharge passage 37 of the high pressure refrigerant passage 32.

After the first and second branch rod portions 74 and 75 branch from the body rod portion 72, the first and second branch rod portions 74 and 75 pass through the first and second throttle flow passages 35 and 36, respectively. Each of the two branch rod portions 74 and 75 is connected to the first and second valves 42 and 44, respectively.

The operation rod 70 moves the first and second valves 42 and 44 while axially moving up and down at the same time as the diaphragm 60 deforms upward and downward. In particular, the first and second throttle passages 35 and 36 are respectively moved.

Accordingly, the first and second valves 42 and 44 can adjust the opening amounts of the first and second throttle passages 35 and 36, respectively, and thus, the first and second valves 42 and 44. It is possible to adjust the opening amounts of the first and second throttle passages 35 and 36 according to the temperature of the refrigerant discharged from the evaporator 8.

Meanwhile, the first and second branch rod portions 74 and 75 of the operation rod 70 are connected to the first and second valves 42 and 44, respectively, and the first and second valves 42 and 44 are connected to maintain the same position with respect to the first and second throttle passages 35 and 36.

The reason for this configuration is that the first and second throttle passages 35 and 36 are maintained by keeping the positions of the first and second valves 42 and 44 with respect to the first and second throttle passages 35 and 36. In order to allow the opening amount of) to be equally adjusted to each other, when the opening amounts between the first and second throttle flow passages 35 and 36 are different from each other, there is a fear that the throttling efficiency is lowered. This is because a so-called "hunting phenomenon" in which the two valves 42 and 44 vibrate may occur.

In the present invention, in order to keep the positions of the first and second valves 42 and 44 with respect to the first and second throttle passages 35 and 36 equal to each other, the first and second branch rod portions 74, The length of 75) was configured equal to each other. Therefore, the opening amounts of the first and second throttle flow passages 35 and 36 can be equally adjusted.

On the other hand, when the positions of the first and second throttle passages 35 and 36 are asymmetric with respect to each other, the first and second throttle passages are adjusted by adjusting the lengths of the first and second branch rod portions 74 and 75. The positions of the first and second valves 42 and 44 with respect to (35, 36) may be kept the same.

Next, an operation example of the present invention having such a configuration will be described with reference to FIG. 3.

First, the operation example of the expansion valve 80 will be described when the refrigerant temperature of the evaporator 8 is in a normal state.

When the refrigerant temperature of the evaporator 8 is normal, the gas 52 of the temperature reduction chamber 50 maintains a balance between expansion and contraction, and when the gas 52 of the temperature reduction chamber 50 maintains the balance, The lower diaphragm 60 also maintains a horizontal state without deformation.

When the diaphragm 60 is maintained in a horizontal state, the lower actuating rod 70 presses the lower first and second valves 42 and 44 to an appropriate pressure, while maintaining a neutral pressure. First and second valves 42 and 44 open the first and second throttle passages 35 and 36 at an optimum opening amount. In particular, open for optimal throttling efficiency.

In this state, the refrigerant in the introduction passage 34 passing through the first and second throttle passages 35 and 36 is discharged to the discharge passage 37 while efficiently throttling, and the discharged refrigerant is discharged from the evaporator 8. Introduced as, the introduced refrigerant takes the heat of the surroundings while passing through the evaporator (8) to generate cold air.

Next, an operation example of the expansion valve 80 will be described when the refrigerant temperature of the evaporator 8 is in an overheated state.

First, when the amount of refrigerant introduced into the evaporator 8 is very small and the refrigerant of the evaporator 8 is overheated, the temperature of the superheated refrigerant is transferred to the temperature reduction chamber 50, and the temperature transferred is the gas of the temperature reduction chamber 50. 52) Inflate.

When the gas 52 of the thermal chamber 50 is expanded, the lower diaphragm 60 is deformed downward, and when the diaphragm 60 is deformed downward, the lower operation rod 70 moves downward. While pressurizing the first and second valves 42 and 44, and the pressurized first and second valves 42 and 44 are spaced apart from the first and second throttle passages 35 and 36 to increase the opening amount. Let's do it.

In this case, since the opening amounts are increased in the two first and second throttle passages 35 and 36, the flow rate of the overall refrigerant is maintained even in a state in which the opening degree increase rate of each of the first and second throttle passages 35 and 36 is minimized. Is increased.

Therefore, while the reduction in the throttling efficiency in the first and second throttle passages 35 and 36 is minimized, the total amount of refrigerant passing through the first and second throttle passages 35 and 36 is increased, and the increased refrigerant is evaporator ( The overheating phenomenon is eliminated as it is introduced in 8), and the refrigerant having been overheated is introduced into the compressor 9 while being properly vaporized.

As a result, the reduction of the throttling efficiency is prevented and the amount of refrigerant supplied to the evaporator 8 is increased, thereby reducing the cooling performance of the evaporator 8 and the overheating of the refrigerant of the evaporator 8 due to the lowering of the throttling efficiency. .

Next, an operation example of the expansion valve 80 will be described when the refrigerant temperature of the evaporator 8 is excessively reduced.

First, when the amount of the refrigerant introduced into the evaporator 8 is too large and the refrigerant of the evaporator 8 is excessively thermally depressed, the temperature of the depleted refrigerant is transmitted to the temperature reduction chamber 50, and the temperature transferred is the temperature of the temperature reduction chamber 50. The gas 52 is contracted.

When the gas 52 of the thermal chamber 50 contracts, the lower diaphragm 60 is deformed to the upper side, and the diaphragm 60 is deformed to the upper side, and the lower operation rod 70 moves upward. While releasing the pressurization of the first and second valves 42 and 44, the released first and second valves 42 and 44 are open to the first and second throttle passages 35 and 36 while being opened. Decreases.

In this case, since the opening amounts are reduced in the two first and second throttle passages 35 and 36, the flow rate of the refrigerant decreases in a state where the opening reduction ratio of each of the first and second throttle passages 35 and 36 is minimized. do.

Therefore, only a small amount of the refrigerant passing through the first and second throttle passages 35 and 36 is reduced, and a small amount of the refrigerant is introduced into the evaporator 8 to prevent thermal phenomenon. And the small amount of the refrigerant, at the same time prevents the refrigerant overheating phenomenon of the evaporator (8) due to the large amount of refrigerant is reduced.

According to the present invention having such a configuration, when the refrigerant temperature of the evaporator 8 is overheated, the flow rate of the refrigerant is increased by increasing the opening amounts of the first and second throttle passages 35 and 36, but the first two places And since the structure is to increase through the second throttle flow path (35, 36), while minimizing the increase in the opening degree of each of the first and second throttle flow path (35, 36), the refrigerant required for the overheating of the refrigerant can be sufficiently increased. have.

Therefore, when the refrigerant temperature of the evaporator 8 is overheated, it is possible to eliminate the overheating of the refrigerant without reducing the throttling efficiency of the refrigerant, and accordingly, the cooling performance of the evaporator 8 due to the decrease in the throttling efficiency of the refrigerant The fall can be prevented in advance, and the refrigerant overheating of the evaporator 8 can be prevented at the same time.

In addition, in the present invention, if the refrigerant temperature of the evaporator 8 is excessively reduced, the flow rate of the refrigerant is reduced by reducing the opening amounts of the first and second throttle passages 35 and 36, Since the structure is reduced through the two throttle flow passages 35 and 36, it is possible to minimize the reduction rate of the openings of the first and second throttle flow passages 35 and 36.

Therefore, even if the refrigerant temperature of the evaporator 8 is excessively reduced, the rate of decrease in the opening degree of the first and second throttle passages 35 and 36 is minimized, so that a sudden decrease in the amount of refrigerant can be prevented and a sudden decrease in the amount of refrigerant can be prevented. As a result, overheating of the refrigerant in the evaporator 8 can be prevented.

On the other hand, the present inventors tested the operation efficiency of the air conditioning system provided with the expansion valve of the present invention in order to find out the performance of the expansion valve of the present invention having such a configuration.

As a result of the test, as shown in FIG. 4, the expansion amount C′-D ′ of the refrigerant expanded by the expansion valve 80 is significantly increased compared to the conventional expansion amount CD shown in FIG. 2. appear. In particular, regardless of whether the refrigerant is overheated in the evaporator 8, the amount of expansion (C'-D ') of the refrigerant is increased, and thus, it can be seen that the pressure (D') of the refrigerant is low. .

As a result, the expansion valve 80 of the present invention improves the cooling efficiency of the evaporator 8 by improving the throttling efficiency of the refrigerant, as well as the evaporator 8 even when the refrigerant of the evaporator 8 is overheated. By efficiently throttling the supplied coolant, the cooling performance of the evaporator 8 can be prevented from being lowered, and the refrigerant overheating of the evaporator 8 can be effectively prevented.

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 embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention.

As described above, according to the expansion valve of the vehicle air conditioning system according to the present invention, since the refrigerant is throttled through a plurality of throttle passages, when the throttle flow rate needs to be increased, the rate of increase in the opening degree of each throttle passage is increased. There is an effect that can increase the throttle flow rate while minimizing.

In addition, the throttling flow rate can be increased while minimizing the increase rate of opening of each throttling passage. Therefore, when the refrigerant of the evaporator is overheated and the flow rate of the refrigerant needs to be increased, the throttling efficiency of the refrigerant decreases due to the rapid opening amount of the throttling passage. The phenomenon can be prevented, and at the same time, a sufficient amount of refrigerant required for overheating of the refrigerant can be secured.

In addition, when the refrigerant of the evaporator is overheated, the structure prevents the reduction of the throttling efficiency of the refrigerant, and when the refrigerant of the evaporator is overheated, there is an effect that the cooling performance of the evaporator can be prevented from being rapidly lowered.

In addition, since the refrigerant is throttled through a plurality of throttle passages, when the throttle flow rate needs to be reduced, the throttle flow rate can be reduced while minimizing the opening reduction rate of each throttle passage.

In addition, since the throttling flow rate can be reduced while minimizing the opening reduction rate of each throttle flow passage, when the refrigerant in the evaporator is excessively desensitized and the flow rate of the refrigerant must be reduced, the refrigerant deterioration of the refrigerant in the evaporator can be eliminated and at the same time It is also possible to prevent the refrigerant overheating of the evaporator due to the rapid decrease in the opening of the flow path.

Claims (3)

In the expansion valve of the vehicle air conditioning system for expanding the refrigerant of the condenser (1) at low temperature and low pressure to supply to the evaporator (8), First and second throttle passages 35 and 36 for throttling the refrigerant introduced from the condenser 1, and the first and second throttle passages 35, depending on the temperature of the refrigerant discharged from the evaporator 8; 36 is an opening amount adjusting device 40 for adjusting the opening amount of 36, The opening amount adjusting device 40, First and second valves (42, 44) disposed corresponding to each of the throttle passages (35, 36) so as to adjust the amount of opening of each of the first and second throttle passages (35, 36); A temperature reduction chamber 50 in which a gas 52 which expands or contracts according to the refrigerant temperature at the outlet side of the evaporator 8 is sealed; A diaphragm 60 installed below the temperature reduction chamber 50 so as to be deformed to the lower or upper portion according to the expansion or contraction of the gas 52; The first and second valves 42 and 44 adjust the opening amount while moving with respect to the first and second throttle passages 35 and 36, respectively, according to the temperature of the refrigerant discharged from the evaporator 8. Expansion valve of the air conditioning system for a vehicle including an operation rod (70) for transmitting the upper and lower deformation movement of the diaphragm (60) to the first and second valves (42, 44). The method of claim 1, The operating rod 70, A body rod portion 72 extending from the bottom surface of the diaphragm 60, and first and second branches branched from the body rod portion 72 and connected to the first and second valves 42 and 44, respectively. Expansion valve of the vehicle air conditioning system comprising a rod (74, 75). 3. The method of claim 2, The first and second branch rod portions 74 and 75 allow the first and second valves 42 and 44 to equally adjust the opening amounts of the first and second throttle flow passages 35 and 36, respectively. Expansion valve of the air conditioning system for a vehicle, characterized in that forming a length.

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