JP2002310537A - Air conditioner for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner for vehicle. SOLUTION: The air conditioner for vehicle comprises a compressor, a heat exchanger communicating with the compressor, a receiver fixed with the heat exchanger while communicating therewith, an evaporator in an evaporator unit communicating with the receiver, and a suction pipe for coupling the evaporator with the compressor wherein the suction pipe is arranged to exchange heat with the receiver.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a vehicle air conditioner.

[0002]

2. Description of the Related Art Conventionally, an air conditioner for a vehicle has been known. Such an air conditioner compresses a refrigerant by a compressor, sends the compressed air to a condenser or a heat exchanger, heat-exchanges the refrigerant by the heat exchanger, and receives a heat. Through the expansion valve, the refrigerant is adiabatically expanded by the expansion valve, and is supplied to the evaporator. Has a cycle of returning to

[0003] Incidentally, in such a vehicle air conditioner, a structure in which a heat exchanger and a receiver are integrated is known, for example, from Japanese Patent Application Laid-Open No. 9-222267. The heat exchanger integrated with a receiver described in the publication is shown in FIG.
As shown in FIG. 2, the heat exchanger includes two header tubes 1 and 2 and a plurality of heat exchange tubes 3 extending between the header tubes 1 and 2. The header tube 1 has two partition plates 4,
5 are provided in the header tube 1 for chambers 6, 7,
The chambers 6 and 8 are provided with a refrigerant inlet 6A and a refrigerant outlet 8A, respectively.

The header tube 2 is provided with two partition plates 9 and 10 at different heights from the partition plates 4 and 5, and chambers 11, 12 and 13 are formed in the header tube 2. A receiver 14 is attached to the header tube 2, and the chamber 12 of the header tube 2 is
The chamber 13 of the header tube 2 is communicated with a receiver outlet formed below the receiver 14.

According to the receiver-integrated heat exchanger having the above-described structure, the pipe connecting the heat exchanger and the receiver can be omitted, and the refrigerant passing through the receiver 14 returns to the heat exchanger. Thus, the heat is further exchanged in the heat exchange tube 3, so that the refrigerant can be supercooled.

[0006]

However, since the refrigerant is in a liquid phase in the region of the heat exchange tube 3 for supercooling the refrigerant in the receiver-integrated heat exchanger having the above structure, the heat exchange performed in such a region is not performed. However, providing a subcooling region in the heat exchanger has a problem that the heat exchange rate per unit area of the heat exchanger is reduced.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and an air conditioner for a vehicle which does not reduce the heat exchange rate per unit area of a heat exchanger while enabling supercooling of a refrigerant. The purpose is to provide.

[0008]

To achieve the above object, an air conditioner for a vehicle according to the present invention comprises a compressor, a heat exchanger connected to the compressor, and a heat exchanger mounted on the heat exchanger. A receiver connected to the container, an evaporator of an evaporator unit connected to the receiver, and a suction pipe connecting the evaporator and the compressor, such that the suction pipe exchanges heat with the receiver. It is characterized by being arranged.

According to the vehicle air conditioner having the above structure, the refrigerant is supercooled by arranging the suction pipe so as to exchange heat with the receiver. The heat exchange rate per unit area can be improved.

[0010] In the present invention, it is preferable that a throttling mechanism for allowing a constant flow rate of the refrigerant to pass therethrough and for decompressing and expanding the refrigerant is provided between the heat exchanger and the receiver.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a vehicle air conditioner according to the present invention will be described with reference to the accompanying drawings.

Referring to FIG. 2, a vehicle air conditioner of a first embodiment according to the present invention is indicated generally by the reference numeral 20. The vehicle air conditioner 20 has a compressor 21.
3 is connected to the refrigerant inlet 25 of the heat exchanger 24.

The heat exchanger 24 includes two header tubes 2
6, 27, and a plurality of heat exchange tubes 28 extending between the header tubes 26, 27. Corrugated fins 28A are provided between the adjacent heat exchange tubes 28. A partition plate 29 is provided in the header tube 26, and chambers 30 and 31 are formed in the header tube 1. The chamber 30 is provided with the above-described refrigerant inlet 25.

In the header tube 27, a partition plate 32 is provided below the partition plate 29 of the header tube 26, and chambers 33 and 34 are formed in the header tube 27. A refrigerant outlet 35 is provided in a chamber 34 of the header tube 27.

The air conditioner 20 also includes a receiver or receiver 3.
6. The receiver 36 is provided with a longitudinal through passage 36.
C has an annular receiver main body 36A configured, and the receiver main body 36A is attached to the header tube 27 by a support member 36B. The receiver main body 36A also has, at its lower part, a refrigerant inlet 38 connected to a refrigerant outlet 35 of the heat exchanger 24 via a connecting pipe 37, and a refrigerant outlet 39.

The air conditioner 20 further includes an evaporator unit. The evaporator unit includes a refrigerant inlet 42 connected to a lower refrigerant outlet 39 of the receiver 36 via a second supply pipe 41, and a compressor 21 via a suction pipe 43. And an evaporator 40 having a refrigerant outlet 45 connected to the refrigerant inlet 44. The second supply pipe 41 is provided with an expansion valve 46 that controls the flow rate of the refrigerant flowing through the second supply pipe 41 according to the refrigeration capacity of the evaporator 40 or the temperature of the suction pipe 43.

As can be clearly understood from FIG. 2, the second supply pipe 41 from the evaporator 40 passes through the longitudinal passage 36C of the receiver 36 and the refrigerant inlet 4 of the compressor 21.
4.

In the vehicle air conditioner having the above structure, the refrigerant is
The gas is turned into a high-pressure and high-temperature gas by the compressor 21 and is sent to the heat exchanger 24 through the first supply pipe 23 under pressure.
It is liquefied by releasing heat. The refrigerant then passes through the heat exchanger 24
Is supplied to the receiver 36 from the refrigerant outlet 35 of the header tube 27 via the connecting pipe 37. The refrigerant passes through a desiccant layer and a filter in the receiver main body 36A, and is discharged from the refrigerant outlet 39 of the receiver main body 36A in a liquid phase. The liquid refrigerant is then supplied to the expansion valve 46 via the second supply pipe 41.
The evaporator 40 is adiabatically expanded by the expansion valve 46 and is supplied to the evaporator 40 in a low-pressure low-temperature gas-liquid mixed state. The refrigerant that has taken the heat of the medium to be cooled by the evaporator 40 is vaporized, exits the refrigerant outlet 45 of the evaporator 40, and is sucked into the refrigerant inlet 44 of the compressor 21 via the suction pipe 43.

The gas refrigerant that has exited the refrigerant outlet 45 of the evaporator 40 is passed through the longitudinal passage 36C of the receiver 36 where the liquid refrigerant is stored before returning to the refrigerant inlet 44 of the compressor 21. And supercooling is performed here.

Referring now to FIG. 3, a vehicle air conditioner according to a second embodiment of the present invention is indicated generally by the reference numeral 50.

In the vehicle air conditioner 50, the expansion valve 46 is removed from the second supply pipe 41 in the vehicle air conditioner 20 of the first embodiment described above.
The only difference is that a throttling mechanism or a capillary 51 for adiabatic expansion of the refrigerant is provided in the 0 connecting pipe 37 for allowing a constant flow of the refrigerant. Therefore, the structure or element of the vehicle air conditioner 50 that is the same as the structure or element of the vehicle air conditioner 20 will not be described repeatedly here,
For convenience of explanation, the same reference numerals as those used for the elements of the vehicle air conditioner 20 are used for the components of the vehicle air conditioner 50 that are the same as the vehicle air conditioner 20.

The capillary 51 itself cannot control the flow rate of the refrigerant according to the refrigerating capacity of the evaporator 40. However, the vehicle air conditioner 50 has a structure in which the suction pipe 43 passes through the longitudinal through passage 36C of the receiver 36.
Therefore, for example, when the refrigerant flow rate is excessive with respect to the refrigerating capacity of the evaporator 40, the temperature of the suction pipe 43 decreases, and the amount corresponding to the temperature decrease amount is reduced by the receiver body 36.
Heat exchange between A and the suction pipe 43 passing therethrough is reduced, and the pressure of the gas in the receiver main body 36A is reduced.
Since the gas pressure in the receiver main body 36A acts to push the liquid refrigerant in the receiver main body 36A toward the evaporator 40, the receiver main body 36A
Due to the decrease in the gas pressure in the inside, the amount of the liquid refrigerant extruded from the receiver main body 36A toward the evaporator 40 is reduced, so that the excessive flow rate of the refrigerant is eliminated. On the other hand, when the temperature of the suction pipe 43 increases, the pressure of the gas in the receiver main body 36A increases, and the amount of liquid refrigerant extruded from the receiver main body 36A toward the evaporator 40 due to the increase in the gas pressure in the receiver main body 36A. Will be increased.

In this way, the structure in which the suction pipe 43 is passed through the receiver 36 allows the flow rate of the refrigerant to be controlled in accordance with the refrigeration capacity of the evaporator 40. Therefore, the expansion valve 46 employed in the vehicle air conditioner 20 is used. Inexpensive, a compact diaphragm mechanism or capillary 51 can be used. In addition, since the throttle mechanism 51 is disposed immediately downstream of the heat exchanger 24, that is, is disposed away from the vehicle cabin, the refrigerant flow noise does not easily reach the occupants.

The present invention can be modified in various ways as described below without being limited to the above-described embodiment.

For example, in each of the above-described embodiments, the suction pipe 43 is passed through the longitudinal passage 36C of the receiver 36, but the suction pipe 43 and the receiver 36 are arranged so as to be able to exchange heat. And the receiver 36 can have any shape. For example,
The receiver 36 is formed in a U-shaped cross section.
The suction pipe 43 may be arranged so as to be surrounded by the V-shaped receiver.

[0026]

As described above, according to the present invention, it is possible to provide an air conditioner for a vehicle which enables supercooling of a refrigerant and does not decrease a heat exchange rate per unit area of a heat exchanger.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a conventional heat exchanger integrated with a receiver.

FIG. 2 is a schematic diagram showing a first embodiment of a vehicle air conditioner according to the present invention.

FIG. 3 is a schematic view showing a second embodiment of the vehicle air conditioner according to the present invention.

[Explanation of symbols]

 21 Compressor 24 Heat exchanger 36 Receiver 40 Evaporator 43 Suction pipe

Claims (2)

[Claims] 1. A compressor, a heat exchanger connected to the compressor, a receiver attached to the heat exchanger and connected to the heat exchanger, and an evaporator of an evaporator unit connected to the receiver. An air conditioner for a vehicle, comprising: a suction pipe that connects the evaporator and the compressor; and the suction pipe is arranged to exchange heat with the receiver. 2. Between the heat exchanger and the receiver,
2. The air conditioner for a vehicle according to claim 1, further comprising a throttle mechanism for allowing the refrigerant at a constant flow rate to pass therethrough for reducing and expanding the refrigerant.