JP3219577B2 - 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 a non-azeotropic mixed refrigerant is filled.

[0002]

2. Description of the Related Art A refrigerant circuit of a conventional air conditioner is shown in FIG. 3, and FIG. 4 is a Mollier diagram of a non-azeotropic mixed refrigerant sealed in the refrigerant circuit of the air conditioner. I have.

During the heating operation of the air conditioner, the gas refrigerant discharged from the compressor 1 is supplied to the four-way valve 2 as shown by a solid arrow.
Through the indoor heat exchanger 3 in the state of a, and heat exchanges with the indoor air sent by the indoor fan 6 in the process of flowing through the indoor heat exchanger 3 to condense and liquefy along the condensation line a to obtain the liquid in the state b. It becomes a refrigerant.

The liquid refrigerant is throttled by the throttle mechanism 4 and adiabatically expanded along the expansion line B to become a gas-liquid two-phase refrigerant in a state c.

The gas-liquid two-phase refrigerant enters the outdoor heat exchanger 5 in the state of c and exchanges heat with the outside air sent by the outdoor fan 7 in the course of flowing through the refrigerant, thereby evaporating along the evaporation line C. It evaporates and becomes a gas refrigerant in the state of d.

This gas refrigerant is sucked into the compressor 1 through the four-way valve 2 and is compressed by the compressor 1 along the compression line d to be discharged in the state a.

[0007] During the cooling operation of the air conditioner, the refrigerant circulates by switching the four-way valve 2 as shown by the dashed arrow, contrary to the above.

In FIG. 4, E is a saturated vapor line, F is a critical point, G is a saturated liquid line, and H and R are isotherms.

A non-azeotropic mixed refrigerant is a mixture of two or more refrigerants having different boiling points. In a gas-liquid two-phase state, the temperature of the refrigerant changes according to the degree of dryness even under a constant pressure.

Therefore, although the state c of the refrigerant at the inlet of the outdoor heat exchanger 5 is on the isothermal line, the dryness increases as the refrigerant evaporates, and the temperature of the refrigerant increases accordingly. Therefore, the state d of the refrigerant at the outlet of the outdoor heat exchanger 5 is located on the isotherm H higher than the isotherm R.

[0011]

In the above-described conventional air conditioner, when the outside air temperature decreases during the heating operation, moisture in the outside air freezes on the surface of the outdoor heat exchanger 5. Since the non-azeotropic mixed refrigerant is sealed in the refrigerant circuit, the dryness of the gas-liquid two-phase refrigerant on the refrigerant inlet side of the outdoor heat exchanger 5 is smaller than that on the refrigerant outlet side. Since the temperature of the refrigerant at the outlet side is lower than that at the outlet side, and the temperature of the refrigerant inlet side of the outdoor heat exchanger 5 is lower than that at the outlet side, the amount of frost near the refrigerant inlet becomes extremely large.

[0012]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and the gist of the first invention is to provide a compressor, an indoor heat exchanger, a throttle mechanism, and an outdoor unit. A non-azeotropic mixed refrigerant is sealed in a refrigerant circuit including a heat exchanger and the like, and the non-azeotropic mixed refrigerant is supplied to the compressor and the chamber during a heating operation.
Flow through the internal heat exchanger, throttle mechanism, and outdoor heat exchanger in this order.
During the cooling operation, the non-azeotropic mixed refrigerant flows in the reverse order to the above.
In the air conditioner that spend flow, the heating operation, the evaporator
The air conditioner is characterized in that the fin pitch on the refrigerant inlet side of the plate fin-and-tube heat exchanger constituting the outdoor heat exchanger functioning as above is made coarser than that on the refrigerant outlet side .

[0013] The gist of the second invention is as follows.
The air conditioner according to claim 1, wherein the refrigerant in the outdoor heat exchanger is
Divide the flow path into two circuits, and
The fin pitch at the center where the wind speed flowing through the heat exchanger is large.
Roughly arranges two circuit refrigerant channels in this part
And the fins on the low wind speed
And one circuit each for this part.
A medium flow path was arranged and adiabatic expansion was performed by the throttle mechanism during heating operation.
Gas-liquid two-phase non-azeotropic refrigerant is located in the central part
After flowing into the refrigerant channels of the two circuits, the above both sides
Flow through the refrigerant flow path of one circuit located in
It is characterized by the following .

[0014]

According to the present invention, in the heating operation of the air conditioner,
The gas-liquid two-phase non-azeotropic mixed refrigerant adiabatically expanded by the throttle mechanism is arranged in a portion where the fin pitch is dense from a portion where the fin pitch of the plate fin and tube type heat exchanger is arranged in a coarse portion . In the process of flowing through the refrigerant flow path in this order, the refrigerant evaporates and returns to the compressor.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention is shown in FIG. The outdoor heat exchanger 50 is a plate fin and tube heat exchanger. The fin pitch of the plate fins of the outdoor heat exchanger 50 is such that a portion 50A near the compressor 1 is dense and a portion 50B near the throttle mechanism 4 is coarse. The other configuration is the same as that of the conventional one shown in FIG. 3, and the corresponding members are denoted by the same reference numerals.

During the heating operation of the air conditioner, the non-azeotropic mixed refrigerant circulates as shown by the solid line arrow, and
The gas-liquid two-phase refrigerant adiabatically expanded with the plate fin-and-tube type outdoor heat exchanger 50 having a coarse fin pitch portion 50
Part 5 with a fine fin pitch via the refrigerant flow path arranged in B
The refrigerant evaporates and evaporates by flowing through the refrigerant flow path arranged at 0A in this order.

The temperature of the refrigerant inlet side 50B of the outdoor heat exchanger 50 becomes lower than the temperature of the refrigerant outlet side 50A, and frost adheres to the plate fins of the refrigerant inlet side 50B earlier than that of the refrigerant outlet side 50A. Since the fin pitch of the plate fins on the inlet side 50B is coarser than that on the refrigerant outlet side 50A, the gap between the adjacent plate fins on the refrigerant inlet side 50B is more likely to be blocked by frost than in the conventional case. ,
It is possible to suppress an increase in the flow resistance of the outside air flowing through the outdoor heat exchanger 50.

On the other hand, during the cooling operation of the air conditioner, the non-azeotropic refrigerant mixture circulates as shown by the dashed arrow, and the fin pitch of the plate fin and tube type outdoor heat exchanger 50 is changed from the dense portion 50A to the coarse portion 50B. The refrigerant is condensed and liquefied in the process of flowing in this order, but the fin pitch of the refrigerant inlet side 50A where the refrigerant condensation temperature is high is denser than the refrigerant outlet side 50B where the refrigerant condensation temperature is low, so that the outdoor heat exchanger 50 The amount of heat transfer increases as compared with the conventional one.

A second embodiment of the present invention is shown in FIG. In this second embodiment, the refrigerant flow path of the plate fin and tube type outdoor heat exchanger 51 is divided into two circuits 52A and 52B, and each circuit 52A and 52B
The throttle mechanisms 4A and 4B are interposed on the indoor heat exchanger 3 side. The center of the outdoor heat exchanger 51 is a portion 51B having a coarse fin pitch, and both sides thereof are portions 51B having a fine fin pitch.
A and 51C.

In the middle part 51B where the wind speed flowing through the outdoor heat exchanger 51 is large , the rough fin pitch 51B has two circuits.
52A and 52B refrigerant flow paths are provided, and a portion 51A where the fin pitch is dense on both sides where the wind speed is low is one circuit 52A.
The refrigerant flow path of the
Refrigerant flow path of the sub Kitto 52B is disposed. The other configuration is the same as that of the conventional one shown in FIG. 3, and the corresponding members are denoted by the same reference numerals.

During the heating operation of the air conditioner, the refrigerant condensed and liquefied in the indoor heat exchanger 3 branches into two refrigerants and adiabatically expands in the throttle mechanisms 4A and 4B. In the course of flowing through the circuits 52A and 52B, the heat is absorbed from the outside air blown by the outdoor fan 7 to evaporate and return to the compressor 1.

At this time, the circuit 52A passes through the aperture mechanism 4A.
Refrigerant flowing into the portion 51B of the central fin pitch is coarse in
Portion 51A where the fin pitch is dense via the arranged refrigerant flow path
Flow through the refrigerant flow path arranged in this order . Meanwhile, refrigerant flowing into the circuit 52B through the throttle mechanism 4B is a central coolant channel fin pitch <br/> fin pitch through arranged refrigerant flow path portion 51B of the crude is disposed in the portion 51C of the dense since the flow <br/> over-, frost without decreasing the capacity of the outdoor heat exchanger 51 can be suppressed. And the central part where the wind speed is high
The fin pitch is rough, so the heat transfer
The fin gap is blocked by frost without lowering
Can be suppressed.

Also, during the cooling operation of the air conditioner, the heat transfer performance of the outdoor heat exchanger 51 can be improved as in the first embodiment.

[0024]

In the present invention, the heating operation of the air conditioner, the non-azeotropic mixed refrigerant adiabatically expanded by the gas-liquid two-phase stop mechanism enter the plate fin and tube type outdoor heat exchanger
Ri, is disposed in a portion Fuinpitchi the coarse of the refrigerant inlet side
Since the fin pitch on the refrigerant outlet side passes through the refrigerant flow path and evaporates and evaporates in the process of flowing through the refrigerant flow path arranged in the dense part in this order, it is possible to suppress frost formation on the outdoor heat exchanger, The interval between the defrosting operations can be made longer than the conventional one, so that the heating feeling can be improved.

Further, during the cooling operation of the air conditioner, the heat transfer amount of the outdoor heat exchanger can be increased as compared with the conventional one.

[Brief description of the drawings]

FIG. 1 is a refrigerant circuit diagram showing a first embodiment of the present invention.

FIG. 2 is a refrigerant circuit diagram showing a second embodiment of the present invention.

FIG. 3 is a refrigerant circuit diagram of a conventional air conditioner.

FIG. 4 is a Mollier diagram of a non-azeotropic refrigerant mixture.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor 3 Indoor heat exchanger 4 Throttle mechanism 50 Outdoor heat exchanger 50A Part with fine fin pitch 50B Part with coarse fin pitch

Claims (2)

(57) [Claims] A non-azeotropic mixed refrigerant is sealed in a refrigerant circuit including a compressor, an indoor heat exchanger, a throttle mechanism, an outdoor heat exchanger, and the like.
Flow through the heat exchanger, throttle mechanism, outdoor heat exchanger in this order,
During cooling operation, the non-azeotropic refrigerant flows in the reverse order
In the air conditioner that spend, during heating operation, as an evaporator
The fin pitch on the refrigerant inlet side of the plate fin and tube heat exchanger that constitutes the outdoor heat exchanger that functions
An air conditioner characterized by being rougher than that on the refrigerant outlet side . 2. The air passage which divides a refrigerant flow path of the outdoor heat exchanger into two circuits and flows through the outdoor heat exchanger.
The fin pitch of the central part where the speed is high is coarse
And the two circuit refrigerant channels
The fin pitch of the parts where the wind speed is low on both sides is
Arrange one circuit refrigerant flow path in each part,
Non-azeotropic two-phase gas-liquid adiabatically expanded by the throttle mechanism during heating operation
Two circuits in which the mixed refrigerant is arranged in the central part
After flowing into the refrigerant flow path, one of the two
2. The air conditioner according to claim 1 , wherein the refrigerant flows through a refrigerant passage of the circuit .