JP3196341B2 - Air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner using a refrigeration cycle having a supercooling degree control valve for controlling the degree of supercooling of a high-pressure refrigerant (hereinafter referred to as "subcooling").

[0002]

2. Description of the Related Art Conventionally, in an accumulator cycle, a subcool control valve 100 as shown in FIG. 15 (see Japanese Utility Model Laid-Open No. 55-85671) is provided downstream of a refrigerant condenser.
There is known a method of obtaining a subcool by providing a subcool. The subcool control valve 100 includes a valve body 103 that opens and closes the throttle unit 102 in conjunction with the diaphragm 101, an adjustment spring 104 that urges the valve body 103 in a direction to open the throttle unit 102, and a refrigerant condenser (not shown) downstream. And a temperature-sensitive cylinder 105 for converting a temperature change of the refrigerant into a pressure change.
The displacement of the valve body 103 is determined by the balance between the pressure in the temperature-sensitive cylinder 105 acting on the upper side of the diaphragm 101 via the capillary tube 106, the high pressure acting on the lower side of the diaphragm 101, and the spring force of the adjusting spring 104. Is adjusted, and the throttle unit 102 is adjusted according to the displacement of the valve body 103.
Is determined.

[0003]

However, the above-mentioned subcool control valve 100 is previously set to a predetermined value (for example, 5 to 1).
Since the spring force of the adjusting spring 104 is set so that a subcool of 0 ° C. can be obtained in the refrigerant condenser, the subcool cycle as shown in FIG. 16 or FIG. (Both are not known cycles), the following problems occur. The subcool cycle shown in FIG. 16 constitutes a heat pump cycle for automotive air conditioning, and includes a refrigerant compressor 200, an indoor condenser 202 arranged in a duct 201 for guiding air to be blown into the vehicle interior, a subcool control valve 100, and a duct 201. Inside, an indoor evaporator 203 and an EPR (evaporation pressure regulating valve) 204 disposed on the windward side of the indoor condenser 202, an outdoor evaporator 205 disposed outside the duct 201, an accumulator 206, and the indoor evaporator 203 and E
Detour 207 bypassing PR 204, and detour 2
07 is provided with an electromagnetic valve 208 for opening and closing.

Now, the bypass 207 is closed (the solenoid valve 208
When the refrigerant flowing out of the subcool control valve 100 is guided to the indoor evaporator 203, the air introduced into the duct 201 by the blower 209 is cooled when passing through the indoor evaporator 203, and thereafter, the indoor condenser 202 is closed. When passing through the vehicle, it is heated and blown out into the vehicle interior. At this time, if the saturation temperature of the refrigerant flowing through the indoor condenser 202 is about 50 ° C., the cool air near 0 ° C. cooled by the indoor evaporator 203 hits the indoor condenser 202, and ideally, the indoor condenser 202 At 202, a subcool near 50 ° C. can be obtained. However, opening the detour 207 (the solenoid valve 2
08 is opened) The refrigerant flowing out of the subcool control valve 100 is guided to the outdoor evaporator 205, and the inside air mode is set to set the inside of the duct 201 at about 30 ° C. (inside air).
Is introduced, the air introduced into the duct 201 is not cooled by the indoor evaporator 203 and strikes the indoor condenser 202 at the same temperature (30 ° C.).
Therefore, in the indoor condenser 202, only a subcool of at most about 20 ° C. can be obtained.

The subcool cycle shown in FIG. 17 constitutes a refrigeration cycle for a vehicle air conditioner. The subcool cycle includes an outdoor condenser 210 upstream of the indoor condenser 202 and regulates the amount of air blown to the indoor condenser 202. An air mix damper 211 is provided.
The indoor evaporator 20 is placed in the indoor condenser 202 by opening and closing.
Cold air near 0 ° C cooled in 3 hits or does not hit. For example, when the air mix damper 211 fully opens the indoor condenser 202 (at the position indicated by the solid line in the figure) and the indoor condenser 202 is exposed to cold air close to 0 ° C., the saturation temperature of the refrigerant flowing through the indoor condenser 202 decreases. If it is around 50 ° C., a subcool near 50 ° C. is ideally obtained. When the air mix damper 211 closes the indoor condenser 202 (at a position indicated by a dashed line in the figure), the indoor condenser 202 is closed.
Does not hit the cool air, the indoor condenser 202 forms a simple refrigerant passage, and if the outside air temperature (the temperature of the wind hitting the outdoor condenser 210) is 30 ° C., the outdoor condenser 210 and the indoor condenser 202 Even if the saturated temperature of the flowing refrigerant is ideally cooled to the ambient temperature of 30 ° C., only a subcool of about 20 ° C. can be obtained.

Therefore, in the subcool cycle shown in FIGS. 16 and 17, if the spring force of the adjusting spring 104 of the subcool control valve 100 is set so that the indoor condenser 202 can obtain a subcool of 20 ° C. Evaporator 2
Even when the cold air near 0 ° C. cooled in 03 hits the indoor condenser 202, the sub-cooler is controlled to 20 ° C. For this reason, as described above, it is not possible to obtain a sufficiently large subcool (50 ° C.) using the cold air near 0 ° C.
Conversely, when the spring force of the adjustment spring 104 of the subcool control valve 100 is set so that a subcool of 50 ° C. is obtained in the indoor condenser 202, the blown air impinging on the indoor condenser 202 in the cycle shown in FIG. Even when the temperature is about 30 ° C. or when the air mix damper 211 closes the indoor condenser 202 in the cycle shown in FIG. Since the opening degree of the opening 102 is to be reduced, the pressure on the high pressure side is greatly increased.

As described above, the conventional subcool control valve 10
At 0, since the spring force of the adjusting spring 104 is set so as to obtain a predetermined subcool in the indoor condenser 202, as described above, the temperature of the air impinging on the indoor condenser 202 greatly changes, and It is not possible to cope with a case where a cycle in which the subcool obtained by the condenser 202 greatly changes is formed (the subcool cannot be controlled by largely changing the subcool), and the cycle efficiency deteriorates. The present invention has been made based on the above circumstances, and an object thereof is to provide at least a downstream region of a refrigerant condenser.
Part of the air-conditioning system,
In the downstream area according to the temperature change of the blast air
It is an object of the present invention to provide an air conditioner whose subcool changes .

[0008]

An air conditioner according to the present invention comprises a room.
A duct that guides the air blown into the room, and
A blower for generating an air flow, and a heat exchange section for condensing and liquefying a refrigerant flowing inside by heat exchange with a cooling medium, and at least a downstream area of the heat exchange section is provided in the duct.
And the air flowing through the duct
A refrigerant condenser in which the refrigerant flowing through the region is cooled, a restrictor that restricts a refrigerant flow path downstream of the refrigerant condenser, a valve body that opens and closes the restrictor, and a pressure change of the refrigerant upstream of the downstream region. A temperature-sensing section for converting the temperature change into a change, and based on the pressure change of the temperature-sensing section, displacing the valve body to open the throttle section so that the degree of supercooling upstream of the downstream area becomes a predetermined value. And a supercooling degree control valve for adjusting the degree. In addition, the refrigerant condenser may further include a mounting pipe for mounting the temperature sensing section, and the mounting pipe may be provided to protrude to the side of the heat exchange section upstream of the downstream area. Means.

[0009]

In the air conditioner of the present invention having the above structure, the opening degree of the throttle portion of the supercooling control valve is adjusted so that the subcool upstream of the downstream portion of the refrigerant condenser has a predetermined value. Accordingly, since the refrigerant flowing into the lower reaches of the refrigerant condenser is a liquid refrigerant that has already been cooled to a subcooled predetermined value, da
Air flowing through the space (the sky flowing from the upstream of the downstream area)
The maximum subcool that can be obtained in the downstream area can be obtained in accordance with the temperature change of the gas . In other words, sent to the downstream area
Even if the temperature changes greatly in the air (air with the refrigerant heat exchanger in the downstream area portion) to be wind, temperature difference between the saturation temperature of the refrigerant temperature and lower reaches portion upstream of the air (the temperature of the air <refrigerant (Saturation temperature).

[0010]

Next, an embodiment of a vehicle air conditioner using a refrigeration cycle according to the present invention will be described with reference to FIGS. FIG. 1 is a schematic configuration diagram of a vehicle air conditioner. The vehicle air conditioner is mounted on an electric vehicle, and includes a duct 1 for guiding blast air into a vehicle interior, a blower 2 for generating an airflow in the duct 1 toward the vehicle interior, and an accumulator-type refrigeration system. Cycle 3 is provided. The duct 1 is provided at its upstream end with an inside air inlet 4 for taking in the vehicle interior air (inside air) into the duct 1 and an outside air introduction port 5 for taking in the outside air of the vehicle (outside air). The amount of introduced air is adjusted by the damper 6. The downstream end of the duct 1 has a DEF outlet 7 for discharging blast air toward the window glass of the vehicle, a VENT outlet 8 for discharging blast air toward the upper body of the occupant, and blast air toward the foot of the occupant. Each of the outlets 7 to 9 communicates with a FOOT outlet 9 for discharging, and each of the outlets 7 to 9 operates in accordance with a selected outlet mode.
It is switched by 1 and 12. Inside the duct 1, the indoor evaporator 13 and the indoor condenser 14 of the refrigeration cycle 3 are provided.
(Refrigerant condenser of the present invention) is provided, and an air mix damper 15 for adjusting the amount of air blown to the indoor condenser 14 is provided. The air mix damper 15 adjusts the ratio between the amount of air passing through the indoor condenser 14 and the amount of air passing through a bypass passage 16 (a passage bypassing the indoor condenser) formed in the duct 1. The temperature of the blown air is adjusted.

The refrigeration cycle 3 has a four-way valve 17 that can switch the refrigerant flow direction.
The heating operation and the cooling operation can be performed based on the switching. The refrigeration cycle 3 receives the air blown by the refrigerant compressor 19 and the electric fan 20, which are rotationally driven by the electric motor 18, in addition to the indoor evaporator 13 and the indoor condenser 14, and functions as an evaporator during the heating operation. An outdoor heat exchanger 21 functioning as a condenser during cooling operation, a subcool control valve 22 (subcooling degree control valve of the present invention) for controlling a subcool obtained by the indoor condenser 14, and an indoor evaporator 13
Evaporation pressure regulating valve 23 (hereinafter referred to as EPR) provided between the air conditioner and the outdoor heat exchanger 21 and an accumulator 24 disposed upstream of the refrigerant compressor 19. Have been. Further, the refrigeration cycle 3 is formed with a bypass 26 that bypasses the indoor evaporator 13 and the EPR 23 and connects the subcool control valve 22 and the outdoor heat exchanger 21. By flowing the refrigerant, heating in the outside air mode (introducing outside air) can be performed without performing dehumidifying heating. The bypass 26 is provided with an electromagnetic valve 27 that opens and closes the bypass 26 and is controlled so as to close the bypass 26 during cooling operation and when performing dehumidifying and heating. In addition, the refrigerant pipe 25 has a cooling operation and a heating operation.
Check valves 28 to 31 for preventing the backflow of the refrigerant are appropriately provided.

In the indoor condenser 14 of the present embodiment, the heat exchanger for exchanging heat between the refrigerant and the blown air includes an upstream section 1.
4a, a middle basin section 14b, and a downstream basin section 14c, which are divided into three basin sections. Each of the basin sections 14a, 14b, and 14c has a counterflow with respect to blast air flowing through the duct 1. The upstream region 14a is disposed on the leeward side in the duct 1 with the 14b therebetween, and the downstream region 14c is provided in a three-layer structure disposed on the leeward side in the duct 1.

Next, the structure of the subcool control valve 22 will be described with reference to FIG. The subcool control valve 22 includes a valve body 22b having a throttle portion 22a formed therein, a diaphragm 22c provided above the valve body 22b, and a valve body 22 that opens and closes the throttle portion 22a in accordance with the displacement of the diaphragm 22c.
d, the pin 22e and the spring guide 22f, the valve body 2 in the direction in which the opening degree of the throttle portion 22a increases (upward in FIG. 2).
An adjusting spring 22g for urging the 2d, a temperature sensing tube 22h (temperature sensing portion of the present invention) for transmitting a change in internal pressure to the upper side of the diaphragm 22c, and an outer portion for transmitting a high pressure upstream of the throttle portion 22a to a lower side of the diaphragm 22c. It is composed of equalizing pipes 22i and the like. An inlet port 22j communicating with the outlet of the indoor condenser 14 and an outlet port 22k communicating with the inlet of the indoor evaporator 13 and the inlet of the detour 26 are attached to the valve body 22b. 22k is communicated via the throttle section 22a. The temperature sensing cylinder 22h
A gas refrigerant is sealed inside, and is provided in contact with a refrigerant passage 14d connecting the midstream region 14b and the downstream region 14c of the indoor condenser 14, and a temperature change of the refrigerant flowing through the refrigerant passage 14d is changed into a pressure change. Then, the pressure change is transmitted to the upper side of the diaphragm 22c via the capillary tube 22l. The outer equalizing pipe 22i is, as shown in FIG.
By taking out the high-pressure pressure upstream of 4c, that is, the refrigerant passage 14d and transmitting it to the lower side of the diaphragm 22c, the effect of the pressure loss due to the flow path resistance of the downstream area 14c of the indoor condenser 14 is prevented.

The valve body 22d is held by a stopper 22n fitted to the head of the valve body 22b via an O-ring 22m, and the stopper 22n is displaced by the displacement of the diaphragm 22c.
2n slides (vertical direction in the figure) with respect to the valve body 22b to open and close the throttle portion 22a. This valve body 22d
Is a temperature-sensitive cylinder 22h acting on the upper side of the diaphragm 22c.
And the high pressure acting on the lower side of the diaphragm 22c and the spring force of the adjusting spring 22g are displaced to a position where they are balanced.
The opening of “a” is determined. The adjusting spring 22g is provided with an adjusting screw 2
The spring force is adjusted by 2o, and the adjusting screw 22o is screwed to a hitch 22q attached to the lower part of the valve body 22b via an O-ring 22p.

The subcool control valve 22 prevents the low-pressure pressure downstream of the throttle portion 22a from being transmitted to the lower side of the diaphragm 22c by the O-ring 22m, and only through the outer equalizing pipe 22i to the lower side of the diaphragm 22c. It is provided to transmit high pressure. Also, the spring guide 22
f, a communication hole 22s communicating the spring housing chamber 22r accommodating the adjustment spring 22g and the upstream of the throttle portion 22a is provided, and the high pressure of the upstream of the throttle portion 22a is reduced through the communication hole 22s. By introducing to
The configuration is such that the effect of the high pressure applied to the spring guide 22f is offset. The subcool control valve 22 of the present embodiment having the above-described configuration has a subcool of a predetermined value (2 to 10 ° C.) between the middle region 14 b and the downstream region 14 c of the indoor condenser 14 in contact with the temperature-sensitive cylinder 22 h. The spring force of the adjustment spring 22g is set such that

Next, the operation of this embodiment will be described with reference to the Mollier diagrams shown in FIGS. Each point on the Mollier diagram shown in FIGS. 3 to 6 indicates each state point of the refrigerant on the cycle shown in FIG. a) When performing a heating operation. The passage of the four-way valve 17 is switched as shown by a solid line in FIG. 1, and the air mix damper 15 is provided with a bypass passage 16 that bypasses the indoor condenser 14 so that all the blown air passes through the indoor condenser 14. Is closed (the position indicated by the solid line in FIG. 1). The high-temperature, high-pressure gas refrigerant (point A in FIG. 3) compressed by the refrigerant compressor 19 passes through the four-way valve 17 and the check valve 29, and as shown by a solid line arrow in FIG.
It is led to 4. In this indoor condenser 14, the upstream region 14
The gas refrigerant having a degree of superheat is cooled at a, and further condensed and liquefied at the middle flow region 14b, and at the outlet of the middle flow region 14b where the temperature-sensitive cylinder 22h comes into contact, the subcool control valve 22 controls the subcool to a predetermined value. (Point B in FIG. 3) is obtained.
The liquid refrigerant having the subcool is subjected to dehumidifying and heating in the inside air mode (introducing inside air), so that when passing through the downstream region 14c of the indoor condenser 14, the indoor refrigerant 13
It is further cooled by the cold air cooled in. As a result, at the outlet of the indoor condenser 14, the temperature difference between the temperature of the cool air and the saturation temperature of the refrigerant upstream of the downstream region 14c (the temperature of the cool air <
The maximum subcool (point C in FIG. 3) that can be obtained in the downstream region 14c can be obtained according to the saturation temperature of the refrigerant).

The liquid refrigerant flowing out of the indoor condenser 14 is decompressed by the subcool control valve 22 (point D in FIG. 3), and then exchanges heat with the blast air flowing through the duct 1 when passing through the indoor evaporator 13 ( (Point E in FIG. 3), and then EPR23
(Point F in FIG. 3), and when passing through the outdoor heat exchanger 21, the air is blown by the electric fan 20 to exchange heat (point G in FIG. 3). The refrigerant evaporated in the outdoor heat exchanger 21 passes through the four-way valve 17 and is guided to the accumulator 24, and only the gas refrigerant is sucked into the refrigerant compressor 19. On the other hand, the inside air introduced into the duct 1 by the operation of the blower 2 is dehumidified by passing through the indoor evaporator 13, and then is superheated when passing through the indoor condenser 14, and the selected outlets 7 to It is blown out into the cabin from 9.

In this heating operation, when dehumidification is not performed, the solenoid valve 27 is opened, so that the refrigerant (point F in FIG. 4) depressurized by the subcool control valve 22 passes through the indoor evaporator 13 and the EPR 23. No, detour 26
After passing through the outdoor heat exchanger 21 and evaporating in the outdoor heat exchanger 21, the refrigerant is sucked into the refrigerant compressor 19 through the accumulator 24 (point G in FIG. 4). In the heating operation in the outside air mode, a liquid refrigerant having a predetermined value of subcool at the outlet of the middle part 14b of the indoor condenser 14 (point B in FIG. 4)
Is cooled by receiving the blast of the outside air introduced into the duct 1 when passing through the downstream region 14c. Therefore, the refrigerant flowing through the downstream region 14c ideally can obtain a subcool (point C in FIG. 4) up to the temperature difference between the temperature of the blown air (outside air temperature) and the saturation temperature of the refrigerant upstream of the downstream region 14c. it can.

B) When cooling operation is performed. The passage of the four-way valve 17 is switched as shown by a broken line in FIG. 1, and the electromagnetic valve 27 provided in the bypass 26 is closed. After passing through the four-way valve 17, the high-temperature, high-pressure gas refrigerant (point A in FIG. 5) compressed by the refrigerant compressor 19 is guided to the outdoor heat exchanger 21 as shown by a broken line arrow in FIG. The air is blown by the electric fan 20 in the heat exchanger 21 and condensed. Thereafter, the refrigerant guided to the indoor condenser 14 through the check valve 31 is further condensed and liquefied by heat exchange with the blown air in the indoor condenser 14. In this indoor condenser 14, as in the case of the heating operation, the subcool control valve 22
As a result, a predetermined value of subcool (point B in FIG. 5) is obtained at the exit of the middle basin section 14b.

Here, when MAX.COOL (maximum cooling) is set, the indoor mix 14 is completely closed by the air mix damper 15 (the position indicated by the dashed line in FIG. 1), and the indoor condensate is cooled. Since the cool air cooled by the indoor evaporator 13 does not hit the vessel 14, the downstream region 14c of the indoor condenser 14 simply constitutes a refrigerant passage. Therefore, the liquid refrigerant having the predetermined value of the subcool is not further cooled when passing through the downstream area 14c of the indoor condenser 14, and the liquid refrigerant having the predetermined value of the subcool is not cooled.
More outflow. Thereafter, the refrigerant (point F in FIG. 5) depressurized by the subcool control valve 22 is evaporated by heat exchange with the blown air in the indoor evaporator 13, and the check valve 28 and the four-way valve 1
After passing through 7, the refrigerant is sucked into the refrigerant compressor 19 through the accumulator 24 (point G in FIG. 5). On the other hand, the blown air (inside air) introduced into the duct 1 by the operation of the blower 2
Is cooled when passing through the indoor evaporator 13, and is blown into the vehicle interior from the selected outlets 7 to 9 through the bypass 16 without passing through the indoor condenser 14.

In this cooling operation, when a part of the cool air cooled by the indoor evaporator 13 is passed through the indoor condenser 14 in accordance with the degree of opening of the air mix damper 15 to control the temperature, a predetermined value is required. When the liquid refrigerant having the value of the subcool (point B in FIG. 6) passes through the downstream area 14c of the indoor condenser 14, it is further cooled by the cool air flowing toward the indoor condenser 14. Therefore, the refrigerant flowing out of the indoor condenser 14 is ideally subcooled up to the temperature difference between the temperature of the cool air and the saturation temperature of the refrigerant upstream of the downstream region 14c (point C in FIG. 6).
Can be obtained. As described above, in the present embodiment, the middle condenser region 14b of the indoor condenser 14 with which the temperature-sensitive cylinder 22h contacts.
The opening of the throttle portion 22a of the subcool control valve 22 is adjusted so that a predetermined value of subcool is obtained at the outlet. For this reason, in the downstream area 14c of the indoor condenser 14, depending on the temperature of the blown air impinging on the downstream area 14c, the downstream area 14c
The maximum subcool that can be obtained by c can be obtained.
In the present embodiment, the indoor condenser 14 has a three-layer structure. However, the indoor condenser 14 may have a two-layer structure of a downstream region 14c and an upper middle region with a portion where the temperature sensing tube 22h contacts. Note that it is not always necessary to form a layer structure, and the upstream region 14a shown in the embodiment,
The midstream region 14b and the downstream region 14c may be configured on the same plane. Further, in the subcool control valve 22, the outer equalizing pipe 22i is used to prevent the influence of the pressure loss of the indoor condenser 14. However, when the influence of the pressure loss of the downstream region 14c does not need to be considered, the outer equalizing pipe 22i is used. 22i need not be used. Although air is shown as a cooling medium for performing heat exchange with the refrigerant flowing through the indoor condenser 14, a liquid such as water or oil may be used.

Next, a second embodiment of the present invention will be described. FIG. 7 is a schematic configuration diagram of an air conditioner for an electric vehicle. The air conditioner of this embodiment enables dehumidification and heating. In the duct 1, an indoor evaporator 13, a subcool heat exchanger 32, and a main condenser 33 are arranged in this order from the upstream side. Is provided with an outdoor evaporator 34 that receives the air from the electric fan 20 and evaporates the refrigerant. The subcool control valve 22 is in contact with the refrigerant passage 14 d connecting the temperature-sensitive cylinder 22 h between the subcool heat exchanger 32 and the main condenser 33,
It is set so that a predetermined value of subcool is obtained at the outlet of the main condenser 33. In this embodiment, the subcooling heat exchanger 32 and the main condenser 33 constitute a refrigerant condenser of the present invention, and the subcooling heat exchanger 32 forms a downstream region of the present invention. When performing dehumidifying heating, the main condenser 3
The liquid refrigerant having a predetermined subcool at the outlet of 3 is further cooled by the cold air cooled by the indoor evaporator 13 when passing through the subcool heat exchanger 32, and the liquid refrigerant having the maximum value that the subcool heat exchanger 32 can take Until you can get a subcool. When the dehumidifying heating is not performed, the liquid refrigerant having the predetermined subcool is supplied to the subcool heat exchanger 3.
When passing through the duct 2, the sub-cool according to the outside air temperature can be obtained by receiving the blowing of the outside air introduced into the duct 1 in the outside air mode.

Next, a third embodiment of the present invention will be described. FIG. 8 is a schematic configuration diagram of an air conditioner for an electric vehicle. The air conditioner of this embodiment performs a cooling operation. The duct 1 includes an indoor evaporator 13 and an indoor heat exchanger 35 on the leeward side of the indoor evaporator 13. Depending on the degree, the amount of air blown to the indoor heat exchanger 35 is adjusted. Outside the duct 1, there is provided an outdoor condenser 36 that receives the air blown by the electric fan 20 and condenses the high-temperature, high-pressure gas refrigerant compressed by the refrigerant compressor 19. The subcool control valve 22 is set such that the temperature-sensitive cylinder 22h is in contact with the refrigerant passage 14d connecting the indoor heat exchanger 35 and the outdoor condenser 36, and a predetermined value of subcool is obtained at the outlet of the outdoor condenser 36. Have been. In this embodiment, the indoor heat exchanger 35 and the outdoor condenser 36 constitute a refrigerant condenser of the present invention, the indoor heat exchanger 35 forms a downstream region of the present invention, and the outdoor condenser 36 It is arranged outside.

Now, when MAX.COOL (maximum cooling) is set, the air mix damper 15 is switched to the indoor heat exchanger 35.
Is completely closed (the position indicated by the dashed line in FIG. 8), the indoor heat exchanger 35 simply constitutes a passage for the refrigerant. Therefore, the liquid refrigerant condensed in the outdoor condenser 36 is not further cooled when passing through the indoor heat exchanger 35, and flows out of the indoor heat exchanger 35 with a predetermined subcool. Depending on the opening degree of the air mix damper 15, a part of the cool air cooled by the indoor evaporator 13 is transferred to the indoor heat exchanger 35.
When the temperature adjustment is performed by passing the air through the indoor heat exchanger 35, when the liquid refrigerant having a predetermined subcool passes through the indoor heat exchanger 35, it is further cooled by the cold air flowing to the indoor heat exchanger 35 side. A subcool according to the temperature can be obtained.

Next, a fourth embodiment of the present invention will be described. FIG. 9 is a front view of the refrigerant condenser. The refrigerant condenser 14 of the present embodiment includes a heat exchanging unit formed by alternately stacking a large number (six in the present embodiment) of tubes 37 and radiating fins 38 forming a refrigerant passage, and both ends of each tube 37. This is a stacked heat exchanger composed of a pair of headers 39 and 40 arranged in a section. The tube 37 is made of an aluminum extrusion and formed flat. The fin 38 is a roller molded product obtained by processing a thin aluminum plate into a wave shape, and has a large number of louvers (not shown) formed on a surface thereof. Header 39, 4
0 has a circular cross section, and a partition plate 41 is provided inside each of the headers 39 and 40. This partition plate 41 makes a U-turn of the refrigerant flowing through the heat exchanging section by partitioning the inside of the headers 39 and 40 in the longitudinal direction, and the header 39 has a second turn from the top in FIG. Third,
The fourth header is provided between the fourth and fifth tubes, the fifth tube and the sixth tube 37, and the other header 40 is provided between the fourth tubes and the fifth tube 37 from the top.

Here, one of the headers 39 partitioned by the three partitioning plates 41 is divided into a first header portion 39 from the top.
a, the second header portion 39b, the third header portion 39c, and the fourth header portion 39d are referred to as the first header portion 39a and the fourth header portion 39d.
The header section 39d has an inlet pipe 42 and an outlet pipe 4 for the refrigerant.
3 are connected to each other, and both ends of a U-shaped mounting pipe 44 (described later) are connected to the second header portion 39b and the third header portion 39c. Each header 39, 4
0 has an elongated hole 45 into which the end of each tube 37 is inserted, and an insertion hole 46 (see FIG. 10) into which the partition plate 41 is inserted is provided on the side opposite to the elongated hole 45. I have. The header 39 has an inlet pipe 42.
A connection hole (not shown) for connecting the outlet pipe 43 and the connection pipe 47 (see FIG. 10) for connecting the mounting pipe 44 is provided. Next, a method of assembling the refrigerant condenser 14 will be described with reference to FIG.
0 is a perspective view showing one header 39 side). First,
After the tubes 37 and the fins 38 are alternately laminated to form a heat exchange section, both ends of each tube 37 are connected to each header 3
The tubes 37, the fins 38, and the headers 3 are inserted by inserting the headers 39 and 40 into the long holes 45 of the tubes 9 and 40.
9 and 40 are fixed. Then, after assembling the partition plate 41, the inlet pipe 42, the outlet pipe 43, and the mounting pipe 44 to each of the headers 39 and 40, the brazing portions are joined by integral brazing to complete the assembling.

The above-described mounting pipe 44 is a pipe for mounting the temperature-sensitive cylinder 22h of the subcool control valve 22. In order to increase the contact area with the temperature-sensitive cylinder 22h, as shown in FIG. The contact portion with 22h is formed to be concave in a concave curved surface shape. In addition, by depressing the contact portion with the temperature-sensitive cylinder 22h, the temperature-sensitive cylinder 22 is attached to the mounting pipe 44a having a circular cross section.
As compared with the case where h is mounted (see FIG. 12), the mounting height H between the mounting pipe 44 and the temperature-sensitive cylinder 22h can be reduced. Thereby, the space for mounting the temperature sensing cylinder 22h can be reduced. In addition, in order to prevent the duct 1 from being enlarged by disposing the mounting pipe 44 in the duct 1, in this embodiment, the mounting pipe 44 is provided to protrude outside the duct 1. .

The refrigerant condenser 14 of this embodiment is controlled by the subcool control valve 22 so that the subcool has a predetermined value in the mounting pipe 44 to which the temperature-sensitive cylinder 22h is mounted. On the further downstream side (downstream area of the present invention), a subcool can be obtained up to the temperature difference between the temperature of the blown air blown to the refrigerant condenser 14 and the saturation temperature of the refrigerant flowing in the mounting pipe 44. That is, by absorbing the temperature fluctuation of the blown air downstream of the mounting pipe 44, a substantially uniform gas-liquid two-phase temperature distribution can be obtained upstream of the mounting pipe 44. Thereby, when the refrigerant condenser 14 is used as a heat exchanger for heating in a heat pump cycle, the temperature distribution of the heat exchange part in the left-right direction (left-right direction in FIG. 9) of the refrigerant condenser 14 is kept substantially uniform. Therefore, the temperature distribution of the air blown into the vehicle cabin can be kept uniform between the driver's seat side and the passenger's seat side.

In this embodiment, the headers 39 and 40 have a circular cross section. However, as shown in FIG. 13, a split type header 48 composed of a plate header 48a and a tank header 48b may be used. In this case, each partition plate 4
No. 1 is not a method of inserting from the outside of the headers 39 and 40 as in the above embodiment, but is assembled by being sandwiched between the plate header 48a and the tank header 48b. Further, in this embodiment, the refrigerant condenser 14 using the stacked heat exchanger is illustrated, but a serpentine heat exchanger as shown in FIG. 14 may be used. In this case, the mounting pipe 44 can be formed by extending a part of the tube 37 that is bent in a meandering shape and protruding from the bracket 49 mounted on the vehicle. The mounting pipe 44 may be formed separately from the tube 37.

[0030]

The air conditioner according to the present invention is provided downstream of the refrigerant condenser.
The region is disposed in the duct, and the throttle opening of the supercooling control valve is adjusted so that the subcool upstream of the downstream region has a predetermined value . Therefore, the maximum subcool that can be obtained in the downstream region can be obtained in accordance with the temperature change of the blown air hitting the downstream region. As a result, it hit the downstream area
Even when the temperature of the blown air greatly changes, an optimal subcool can be obtained to increase the cycle efficiency.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a vehicle air conditioner.

FIG. 2 is a sectional view of a subcool control valve.

FIG. 3 is a Mollier diagram of a refrigeration cycle.

FIG. 4 is a Mollier diagram of a refrigeration cycle.

FIG. 5 is a Mollier diagram of a refrigeration cycle.

FIG. 6 is a Mollier diagram of a refrigeration cycle.

FIG. 7 is a schematic configuration diagram of an air conditioner showing a second embodiment of the present invention.

FIG. 8 is a schematic configuration diagram of an air conditioner showing a third embodiment of the present invention.

FIG. 9 is a front view of a refrigerant condenser according to a fourth embodiment of the present invention.

FIG. 10 is an exploded perspective view of a main part of a refrigerant condenser according to a fourth embodiment of the present invention.

FIG. 11 is a sectional view of a mounting pipe and a temperature-sensitive cylinder according to a fourth embodiment of the present invention.

FIG. 12 is a cross-sectional view of a mounting pipe and a temperature-sensitive cylinder showing a comparison with FIG. 11;

FIG. 13 is an exploded perspective view of a header according to a modification of the fourth embodiment.

FIG. 14 is a front view of a refrigerant condenser according to a modification of the fourth embodiment.

FIG. 15 is a schematic configuration diagram of a conventional subcool control valve.

FIG. 16 is a schematic configuration diagram of an air conditioner according to the related art.

FIG. 17 is a schematic configuration diagram of an air conditioner according to the related art.

[Description of Signs] 1 duct 2 blower 3 refrigeration cycle 14 indoor condenser (refrigerant condenser) 14c downstream area 22 subcool control valve (supercooling degree control valve) 22h temperature sensing cylinder (temperature sensing section) 22a throttle valve 22d valve Body 44 Piping for mounting

──────────────────────────────────────────────────続 き Continuing from the front page (72) Keita Honda, 1-1-1, Showa-cho, Kariya-shi, Aichi Japan Inside Denso Co., Ltd. (72) Ryoichi Sanada 1-1-1, Showa-cho, Kariya-shi, Aichi Japan Japan Denso Stock In-company (72) Inventor Kunio Iriya 1-1-1 Showa-cho, Kariya-shi, Aichi Japan Inside Denso Co., Ltd. (56) References JP-B Sho 57-6020 (JP, B2) (58) Field surveyed (Int.Cl . ^7, DB name) F25B 1/00 B60H 1/22

Claims (2)

(57) [Claims] A duct for guiding blast air into a room, and a blower for generating an airflow in the duct toward the room.
And a heat exchange unit that condenses and liquefies the refrigerant flowing through the heat exchange with the cooling medium, at least a downstream area of the heat exchange unit is disposed in the duct, and the air flowing through the duct is provided.
A refrigerant condenser in which the refrigerant flowing through the downstream region is cooled by air, a throttle portion that narrows a refrigerant flow path downstream of the refrigerant condenser, a valve body that opens and closes the throttle portion, and a refrigerant upstream of the downstream region portion. A temperature-sensing unit that converts a temperature change into a pressure change, based on the pressure change of the temperature-sensing unit, displacing the valve body so that the degree of supercooling upstream of the downstream area becomes a predetermined value; An air conditioner comprising a supercooling degree control valve for adjusting an opening degree of a throttle section. 2. The refrigerant condenser according to claim 1, further comprising a mounting pipe for mounting the temperature sensing part, the mounting pipe protruding from a side of the heat exchange part upstream of the downstream area. The air conditioner according to claim 1, wherein: