JP3486851B2 - 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 in which two heat exchangers arranged in an air conditioning path are provided with functions such as cooling, heating and dehumidification.

[0002]

2. Description of the Related Art Conventionally, as an air conditioner having a dehumidifying function at the time of heating, there is known an air conditioner disclosed in Japanese Patent Publication No. 52-13025. This is, as shown in FIG. 4, one end of the first heat exchanger B arranged on the upstream side of the air conditioning path A and one end of the second heat exchanger C arranged on the downstream side of the same path. Are connected in series via a dehumidifying decompression / expansion mechanism D, and extend from the other end of the first heat exchanger B to the other end of the second heat exchanger C, the compressor E, and the third outside the air conditioning path. Heat exchanger F, heating decompression expansion mechanism G, open / close valve M
Are sequentially connected and configured. The first and third
In the middle of the piping between the heat exchangers B and F and the compressor E of
A four-way valve H is provided so that the flow of the refrigerant pressure-fed from the compressor E can be reversed. Further, the check valve I is provided in parallel with the dehumidifying decompression expansion mechanism D, and the cooling decompression expansion mechanism N is provided between the second heat exchanger C and one end of the on-off valve M. Exchanger B and open / close valve M
An on-off valve O is provided between the other end and the other end. Further, a check valve J connected in parallel to the heating decompression / expansion mechanism G
And a check valve L connected in parallel to the dehumidifying decompression expansion mechanism K, the third heat exchanger F and the heating decompression expansion mechanism G, and a dehumidification decompression expansion mechanism K connected in parallel. An on-off valve P is provided.

In such a structure, during cooling operation,
The open / close valves O and P are opened, the open / close valve M is closed, and the four-way valve is set as shown by the solid line. During the dehumidifying and cooling operation, the open / close valves M and P are opened and the open / close valve O is closed, and the four-way valve is also shown by the solid line. To set. Also, during heating operation, the on-off valves O and P are closed, and the on-off valve M is opened, and the four-way valve is set as shown by the broken line. During dehumidification heating operation, the on-off valve M is opened and the on-off valves O and P are opened. Close it and set the 4-way valve as shown by the solid line.

[0004]

However, in the above-mentioned technique, since the four-way valve is used for switching the air conditioning mode, the pressure loss of the refrigerant becomes large and the high-temperature refrigerant and the low-temperature refrigerant flowing through the four-way valve at the same time. However, there was a drawback that heat was exchanged with this four-way valve.

Therefore, in the present invention, in order to overcome the above-mentioned drawbacks, cooling, dehumidifying and cooling without a four-way valve,
An object of the present invention is to provide an air conditioner capable of switching to each operation mode such as heating and dehumidifying heating.

[0006]

SUMMARY OF THE INVENTION However, the gist of the present invention is to provide a compressor, a first heat exchanger which is arranged in an air conditioning duct and whose ventilation amount is adjusted by a damper, and an air conditioning duct. And a second heat exchanger arranged upstream of the first heat exchanger, a third heat exchanger arranged outside the air conditioning duct, and first and second expansion devices. Having the compressor, the first heat exchanger, the first expansion device, the third heat exchanger, an opening / closing valve or a check valve, the second expansion device, a second heat exchanger. To form a loop, and between the inflow side and the outflow side of the first expansion device, and between the outflow side of the first heat exchanger and the inflow side of the second expansion device. , And a passage opened and closed by an on-off valve between the outflow side of the third heat exchanger and the suction side of the compressor. Lies in the fact digits.

Looking concretely in relation to the operation mode, the book
An air conditioning apparatus according to the invention, the compressors, the air conditioning duct
First heat that is placed inside the chamber and the amount of ventilation is adjusted by the damper
An exchanger and the first heat exchange in the air conditioning duct
A second heat exchanger arranged upstream of the air conditioner and the air conditioner
And a third heat exchanger arranged outside
In the mode, the refrigerant discharged from the compressor is
After radiating heat in the first heat exchanger, in the third heat exchanger
Absorb heat, and then bypass the second heat exchanger
Characterized by returning to the compressor
There is.

Further , the air conditioner according to the present invention is
Ventilation volume with a presser and damper installed in the air conditioning duct
In the air conditioning duct and the first heat exchanger
Second heat placed upstream of the first heat exchanger
Exchanger and third heat exchange located outside the air conditioning duct
And a compressor for controlling the compressor in the dehumidification heating operation mode.
The heat discharged from the refrigerant discharged from the first heat exchanger
Later, the third heat exchanger is made to absorb heat, and then the
It is returned to the compressor and discharged from the compressor.
After the second refrigerant is radiated by the first heat exchanger,
Heat is absorbed by the heat exchanger of
The feature is that it was returned.

Further, the air conditioner according to the present invention is
It is placed in the compressor and the air conditioning duct to ventilate with the damper.
A first heat exchanger of which the quantity is adjusted and in the air conditioning duct
A second heat exchanger arranged upstream of the first heat exchanger
A heat exchanger and a third heat exchanger arranged outside the air conditioning duct.
And a dehumidifying cooling operation mode in the cooling operation mode.
The refrigerant discharged from the compressor at the
After radiating heat with the heat exchanger of
Before radiating heat to the second heat exchanger
It is characterized by returning to the compressor
It

[0010]

Therefore, during the cooling operation, the on-off valve between the third heat exchanger and the second expansion valve and the on-off valve between the inflow side and the outflow side of the first expansion device are opened, If the other on-off valve is closed and the damper is set to a position where the ventilation volume of the first heat exchanger is eliminated, the refrigerant discharged from the compressor is
The second heat exchanger passes through the first heat exchanger without radiating heat, passes through the first on-off valve, radiates heat by the third heat exchanger, and is decompressed by the second expansion valve, and then the second heat exchanger. Absorbs heat. In this case, the air sent from the upstream in the air conditioning duct is
Is cooled when passing through the heat exchanger, and bypasses the first heat exchanger to be supplied to the temperature controlled space.

In this state, if the damper opening is set to the intermediate position, a part of the air cooled by the second heat exchanger is heated when passing through the first heat exchanger, so that it is in the cooling state. However, the bilevel mode can be formed. Further, when the damper is set at the position where the air flow rate of the first heat exchanger is maximum or at the intermediate position, the air sent from the upstream passes through the second heat exchanger. At this time, it is dehumidified while being cooled, and is heated when passing through the first heat exchanger, so that the dehumidifying mode of cooling only can be obtained.

During the heating operation, the on-off valve between the outflow side of the third heat exchanger and the suction side of the compressor is opened, the other on-off valves are closed, and the damper is connected to the first heat exchanger. When set to the position where the ventilation volume is maximum, the refrigerant discharged from the compressor radiates heat in the first heat exchanger, is decompressed in the first expansion device, and then absorbs heat in the third heat exchanger, 2 Returned to the compressor without passing through the heat exchanger. In this case, the air sent from the upstream in the air conditioning duct does not undergo any heat exchange in the second heat exchanger, but is heated when passing through the first heat exchanger and is supplied to the temperature-controlled space. .

In this state, if the damper opening is set to the intermediate position, a part of the air sent from the upstream bypasses the first heat exchanger and is not heated. Modes can be formed.

Further, during the dehumidifying and heating operation, between the outflow side of the first heat exchanger and the inflow side of the second expansion device, and between the outflow side of the third heat exchanger and the suction side of the compressor. Open the open / close valve of the other, close the other open / close valves, and set the damper to the first position.
If you set it to the position where the ventilation volume of the heat exchanger is maximum,
The refrigerant discharged from the compressor radiates heat in the first heat exchanger, is then decompressed in the first expansion device and absorbed in the third heat exchanger, and is decompressed in the second expansion device and then decompressed in the second expansion device. The second heat exchanger splits into a heat absorbing path and reaches the compressor. For this reason, the air sent from the upstream is dehumidified when passing through the second heat exchanger, and then heated in the first heat exchanger to be dried as a whole into the temperature-controlled space as hot air. Supplied.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3, an air conditioner according to the present invention is shown. The air conditioner is mounted on, for example, an automobile, and the first and second heat exchangers 2 arranged in an air conditioning duct 1 are shown. , 3 and a third heat exchanger 4 arranged outside the air conditioning duct 1.

An inside / outside air switching device is provided on the most upstream side of the air conditioning duct 1, and the inside air inlet and the outside air inlet are selectively opened by an intake door. The inside air or the outside air selectively introduced into the air conditioning duct 1 is sucked by the rotation of the blower, sent to the first and second heat exchangers 2 and 3, where heat is exchanged there from a desired outlet. It is designed to be supplied to the passenger compartment.

The first heat exchanger 2 is arranged on the downstream side of the second heat exchanger 3, and a damper 5 is provided on the upstream side of the first heat exchanger 2. ing. The damper 5 can be varied from a position where the amount of air passing through the first heat exchanger 2 is maximum (opening 100%) to a position where it is minimum (opening 0%) to adjust the opening. As a result, the ratio of the air passing through the first heat exchanger 2 to the air bypassing the first heat exchanger 2 can be changed.

The inflow side 2a of the first heat exchanger 2 is connected to the discharge side A of the compressor 6, and the outflow side 2b of the first heat exchanger 2 is connected to the inflow side 7a of the first expansion valve 7. It is connected. The inflow side 3 a of the second heat exchanger 3 is connected to the outflow side 8 b of the second expansion valve 8, and the outflow side 3 b of the second heat exchanger 3 is connected to the suction side B of the compressor 6. Has been done.

The inflow side 4a of the third heat exchanger 4
Is connected to the outflow side 7b of the first expansion valve 7, and the outflow side 4b of the third heat exchanger 4 flows into the second expansion valve 8 via the first on-off valve 9 which is an electromagnetic valve. It is connected to the side 8a.

Further, between the inflow side 7a and the outflow side 7b of the first expansion valve 7, there is provided a passage opened and closed by the second on-off valve 10 which is an electromagnetic valve, and the first heat exchanger 2 Is provided between the outflow side 2b of the second expansion valve 8 and the inflow side 8a of the second expansion valve 8, and a passage opened and closed by the third on-off valve 11 formed of an electromagnetic valve is provided. And a suction side B of the compressor 6 between the fourth opening / closing valve 1 which is an electromagnetic valve.
A passage that is opened and closed by 2 is provided.

Opening and closing of the on-off valves 9, 10, 11, 12;
The opening degree of the damper 5 is controlled by a control signal from the control unit 13. The control unit 13 is a well-known one having an input circuit including an A / D converter, a multiplexer, etc., an arithmetic processing circuit including a ROM, a RAM, a CPU, etc., and an output circuit including a driving circuit, etc., and sets an operation mode. Setting signals and the like are input, and these signals are processed according to a predetermined program.

Next, among control operations by the control unit 13, specific control operation examples of the on-off valves 9 to 12 and the damper 5 will be described for each operation mode.

First, when the operation mode is set to the cooling operation mode, the control unit 13 opens the first and second on-off valves 9 and 10, as shown in FIG.
The third and fourth on-off valves 11 and 12 are closed, and the damper 5 is set to the position where the opening degree is 0% (the position shown by the solid line).
Therefore, the compressed refrigerant flowing out from the discharge side A of the compressor 6 passes therethrough without radiating heat because there is no air passing through the first heat exchanger 2 and passes through the second on-off valve 10 to the second side. The second expansion valve 8 via the first on-off valve 9 after entering the heat exchanger 4 of No. 3 and radiating heat (condensation and liquefaction) there
Then, the pressure is reduced by the second expansion valve 8, enters the second heat exchanger 3, where the heat is absorbed (evaporated and vaporized) and then returned to the compressor 6. Therefore, the air sent from the upstream side is cooled by the second heat exchanger 3, bypasses the first heat exchanger 2, and is directly supplied to the vehicle interior.

When the operation mode is set to the cooling bi-level operation mode, the damper 5 is set to the intermediate position (the position shown by the broken line) while keeping the same refrigerant circulation path as in the cooling operation mode. . Therefore, the compressor 6
The compressed refrigerant flowing out from the discharge side A is also radiated in the first heat exchanger 2, radiated again in the third heat exchanger 4 (condensation and liquefaction), and decompressed in the second expansion valve 8 to be the first pressure. 2 heat exchanger 3
Then, the heat is absorbed here (evaporated and vaporized) and then returned to the compressor 6. Therefore, the air sent from the upstream is cooled by the second heat exchanger 3, a part of the air passes through the first heat exchanger 2, is reheated, and passes through the first heat exchanger 2. A temperature difference is formed between the charged air and the bypassed air (a bilevel state is formed), and the air is supplied into the vehicle interior.

Further, when the operation mode is set to the dehumidifying and cooling operation mode, the damper 5 is at the position where the opening degree is 0% (the position shown by the solid line) with the same refrigerant circulation path as in the cooling operation mode. Set to any intermediate position from 100% to 100%. Therefore, the compressed refrigerant flowing out from the discharge side A of the compressor 6 is appropriately heat-exchanged in the first heat exchanger 2 and passes through it, and enters the third heat exchanger 4 to radiate heat (condensed liquefaction). ), The pressure is reduced by the second expansion valve 8, enters the second heat exchanger 3, where the heat is absorbed (evaporated and vaporized) and then returned to the compressor 6. For this reason, the air sent from the upstream is dehumidified and cooled in the second heat exchanger 3, and a part of it is reheated when passing through the first heat exchanger 2, and the second heat exchanger 3 Due to the dehumidifying action of, the temperature lowered too much is raised to a predetermined temperature and supplied to the vehicle interior.

When the operation mode is set to the heating operation mode, as shown in FIG. 2, the control unit 13 opens the fourth on-off valve 12, and the first, second, and third valves are opened.
The on-off valves 9, 10, and 11 are closed, and the damper 5 is set at the position of 100% opening (position shown by the solid line). Therefore, the compressed refrigerant flowing out from the discharge side A of the compressor 6 radiates heat (condensation and liquefaction) in the first heat exchanger 2 and is decompressed by the first expansion valve 7 to reach the third heat exchanger 4. After the heat is absorbed (evaporated and vaporized) here, the heat is returned to the compressor 6 via the fourth on-off valve 12. Therefore, the air sent from the upstream passes through the second heat exchanger 3 but is not heat-exchanged, and is entirely guided to the first heat exchanger 2 to be heated and supplied into the vehicle interior.

When the operation mode is set to the heating bi-level operation mode, the damper 5 is set to the intermediate position (the position shown by the broken line) while keeping the same refrigerant circulation path as the heating operation mode. . Therefore, a part of the air sent from the upstream is sent to the rear without bypassing the heat exchange by bypassing the first heat exchanger 2, and the rest is heated by the first heat exchanger 2. Are sent to the rear, form a temperature difference (form a bilevel state), and are supplied into the vehicle interior.
In this operation mode, the third opening / closing valve 11 is opened, and the refrigerant passing through the first heat exchanger 2 is transferred to the second expansion valve 8
Alternatively, the pressure may be reduced by, and the second heat exchanger 3 may evaporate and vaporize. In this case, the air sent from the upstream is
It is once cooled by the second heat exchanger 3, and a part of it is reheated by the first heat exchanger 2 to form a bilevel state.

When the operation mode is set to the dehumidifying and heating operation mode, the control unit 13 opens the third and fourth on-off valves 11 and 12, as shown in FIG.
The first and second on-off valves 9 and 10 are closed, and the damper 5
Is set to a position where the opening is 100% (position shown by a solid line). Therefore, the compressed refrigerant flowing out from the discharge side A of the compressor 6 is radiated (condensed and liquefied) by the first heat exchanger 2 and decompressed by the first expansion valve 7 as in the heating operation.
To the heat exchanger 4 where the heat is absorbed (evaporated and vaporized) and then returned to the compressor 6 via the fourth on-off valve 12. At the same time, the refrigerant that has passed through the first heat exchanger 2 is decompressed by the second expansion valve 8 and reaches the second heat exchanger 3, where heat is absorbed (evaporated and vaporized) and then the compressor 6
Returned to. Therefore, the air sent from the upstream is
The first heat exchanger 2 is dehumidified by the second heat exchanger 3.
It is heated when it passes through and is supplied to the vehicle interior as dry warm air.

The above operation modes can be summarized as shown in Table 1 below.

[0030]

[Table 1]

Incidentally, with respect to the cycle configuration of FIGS. 1 to 3,
The first opening / closing valve 9 may be replaced with a check valve 9 ′ that allows only the flow from the outflow side 4b of the third heat exchanger 4 to the inflow side 8a of the second expansion valve 8. During the heating operation, the outflow side 4b of the third heat exchanger 4 is at a lower pressure than the inflow side 8a of the second expansion valve 8, so even if the check valve is used in this manner, the same effect as described above can be obtained. can get.

[0032]

As described above, according to the present invention,
A compressor, a first heat exchanger, the first expansion device,
A cycle is formed in the order of the third heat exchanger, the on-off valve or the check valve, the second expansion device, and the second heat exchanger, and further, a cycle is formed between the inflow side and the outflow side of the first expansion device. Between the outflow side of the first heat exchanger and the inflow side of the second expansion device, and between the outflow side of the third heat exchanger and the suction side of the compressor with open / close valves. Since the passage is provided, various operating modes such as cooling, cooling by-level, dehumidifying and cooling, heating, heating by-level, dehumidifying and heating do not need to use the four-way valve by controlling the opening of the damper and the on-off valve. Can also be switched. Therefore, unlike the four-way valve, there is no risk of heat exchange between the high pressure side refrigerant and the low pressure side refrigerant.

[Brief description of drawings]

FIG. 1 shows an air conditioner according to the present invention.
FIG. 1A shows a cycle configuration showing a refrigerant flow path during cooling, cooling bilevel, and dehumidifying cooling operation, and FIG.
FIG. 6 is a schematic configuration diagram showing a damper position at that time.

FIG. 2 (a) shows a cycle configuration showing a refrigerant flow path during heating and heating bi-level operation, and FIG. 2 (b).
FIG. 6 is a schematic configuration diagram showing a damper position at that time.

FIG. 3 (a) is a cycle configuration showing a refrigerant flow path during a dehumidifying heating operation, and FIG. 3 (b) is a schematic configuration diagram showing a damper position at that time.

FIG. 4 is a configuration diagram showing a conventional air conditioner.

[Explanation of symbols]

1 air conditioning duct 2 First heat exchanger 3 Second heat exchanger 4th heat exchanger 5 damper 6 compressor 7 First expansion valve 8 Second expansion valve 9 First on-off valve 10 Second on-off valve 11 Third on-off valve 12 Fourth on-off valve

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) F25B 29/00 401

Claims (4)

(57) [Claims] 1. A compressor, a first heat exchanger arranged in an air-conditioning duct and having a ventilation amount adjusted by a damper, and arranged in the air-conditioning duct on the upstream side of the first heat exchanger. A second heat exchanger, a third heat exchanger arranged outside the air conditioning duct, and first and second expansion devices, the compressor, the first heat exchanger, The first expansion device, the third heat exchanger, the on-off valve or check valve, the second expansion device, and the second heat exchanger are connected in this order to form a loop, and Between the inflow side and the outflow side of the first expansion device, the outflow side of the first heat exchanger and the inflow side of the second expansion device, and the outflow side of the third heat exchanger. An air conditioner characterized in that a passage opened and closed by an on-off valve is provided between the intake side of the compressor and the suction side. 2. A compressor and an air conditioning duct disposed in the duct.
The first heat exchanger whose ventilation is adjusted by the damper
In the air conditioning duct, on the upstream side of the first heat exchanger.
Second heat exchanger arranged and arranged outside the air conditioning duct
And a third heat exchanger that is
Is the first heat of the refrigerant discharged from the compressor.
After the heat is dissipated by the exchanger, the heat is absorbed by the third heat exchanger.
And then bypassing the second heat exchanger
An air conditioner characterized by being returned to the compressor
Japanese device. 3. A compressor and an air conditioning duct disposed in the air conditioning duct.
The first heat exchanger whose ventilation is adjusted by the damper
In the air conditioning duct, on the upstream side of the first heat exchanger.
Second heat exchanger arranged and arranged outside the air conditioning duct
And a third heat exchanger that is
The refrigerant discharged from the compressor is stored in the first
After the heat is dissipated by the heat exchanger, the heat is absorbed by the third heat exchanger.
Then, after returning to the compressor,
The refrigerant discharged from the compressor is discharged by the first heat exchanger.
After heating, heat is absorbed by the second heat exchanger, and then
It is characterized in that it is returned to the compressor
Air conditioner. 4. A compressor and an air conditioning duct disposed in the duct.
The first heat exchanger whose ventilation is adjusted by the damper
In the air conditioning duct, on the upstream side of the first heat exchanger.
Second heat exchanger arranged and arranged outside the air conditioning duct
And a third heat exchanger that is operated in the cooling operation mode or
Discharge from the compressor in dehumidifying and cooling operation mode
After radiating the generated refrigerant in the first heat exchanger,
Heat is further dissipated by the heat exchanger of No. 3, and then the second heat exchanger
A heat exchanger is used to absorb heat and return it to the compressor.
An air conditioner characterized by.