JP3089097B2 - 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 having a hot gas bypass pipe.

[0002]

2. Description of the Related Art FIG. 4 shows a refrigerant circuit of a conventional air conditioner of this type. During the heating operation of the air conditioner, the high-temperature gas refrigerant discharged from the compressor 1 enters the indoor heat exchanger 3 via the four-way valve 2, where it condenses and liquefies by heating the indoor air. After being adiabatically expanded by being throttled by the throttle mechanism 5, the liquid refrigerant enters the outdoor heat exchanger 4, where it evaporates by absorbing heat from the outside air. Then, the gas refrigerant is sucked into the compressor 1 via the four-way valve 2.

When frost 7 adheres to the surface of the outdoor heat exchanger 4, the defrosting operation is performed by opening the on-off valve 6 interposed in the hot gas bypass pipe 8. In this defrosting operation, the high-temperature gas refrigerant discharged from the compressor 1 passes through a hot gas bypass pipe 8 and an on-off valve 6, and enters a point B of a refrigerant pipe connecting the throttle mechanism 5 and the outdoor heat exchanger 4. In the process of flowing through the collecting part 4d, the branch pipe 4c, and the circuits 4a and 4b of the outdoor heat exchanger 4, the heat exchanges with the frost 7 adhered to the surface of the outdoor heat exchanger 4 and is melted.

[0004]

In the above-described conventional air conditioner, when the high-temperature and high-pressure gas refrigerant is supplied to the outdoor heat exchanger 4 through the hot gas bypass pipe 8 during the defrosting operation, the outdoor Since the heat exchanger 4 is at a low temperature of 0 ° C. or lower, as shown in FIG. 5, the refrigerant is condensed and liquefied at the refrigerant inlet side, that is, at the lower part of the outdoor heat exchanger 4, and is accumulated in the collecting part 4d.
Only the low-temperature and low-pressure gas refrigerant flows in the circuits 4a and 4b thereabove. Therefore, if the temperature of the liquid refrigerant accumulated in the collecting part 4d does not rise, defrosting on the upper part of the outdoor heat exchanger 4 does not proceed. Then, since the liquid refrigerant accumulated in the collecting part 4d exchanges heat with the high-temperature gas refrigerant and radiates heat from the liquid refrigerant in the process of increasing the temperature, the defrosting time is further increased. In addition, since the liquid refrigerant in the collecting part 4d is present in the path of the gas refrigerant, a pressure difference is generated, and the refrigerant evaporates on the downstream side of the liquid refrigerant. As a result, the refrigerant enters the outdoor heat exchanger 4. There is a problem that the amount of the staying liquid refrigerant is reduced, and excessive liquid refrigerant is concentrated on the compressor 1 to hinder the durability of the compressor 1.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and its gist is to provide an outdoor heat exchanger having a plurality of circuits extending substantially vertically. When, is interposed a high-temperature gas refrigerant discharged from the compressors to the hot gas bypass pipe, the hot gas bypass pipe to be supplied to the outdoor heat exchanger
An air conditioner having an on- off valve that opens during defrosting operation, wherein the hot gas bypass pipe is provided on the downstream side of the on-off valve.
Divide the pipes into two or more pipes.
Connected to the intermediate height position of each of the plurality of circuits extending in the vertical direction, so that the high-temperature gas refrigerant flows upward through the upper half of each circuit above the intermediate height position during the defrosting operation. The air conditioner is characterized in that

[0006]

According to the present invention, during the defrosting operation, the high-temperature gas refrigerant discharged from the compressor is supplied to the hot gas bypass pipe and the hot gas bypass pipe.
Branch via the on- off valve interposed in the
It flows into the plurality of intermediate height position of the Saki'<br/> preparative extending in the vertical direction of the outdoor heat exchanger, the above each circuit
The upper half portion upward and flow through, since the liquid refrigerant condensed in the process accumulates in the bottom of each circuit, does not block the path of the gas refrigerant. Further, since the excess liquid refrigerant concentrated in the compressor is collected in the outdoor heat exchanger, the operation of the compressor is properly maintained.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention is shown in FIG. As shown in FIG. 1, the other end of the hot gas bypass pipe 8 having one end connected to the discharge pipe 9 is caused to branch into a plurality of each branch
The tip of the tube is connected to a substantially intermediate height position A of each of the circuits 4a and 4b extending in the vertical direction of the outdoor heat exchanger 4. The other configuration is the same as that of the conventional one shown in FIG.

When the on-off valve 6 is opened during the defrosting operation of the air conditioner, the high-temperature gas refrigerant discharged from the compressor 1 is discharged from the discharge pipe 9, the hot gas bypass pipe 8, the on-off valve 6,
A is connected to each circuit 4a, 4b of the outdoor heat exchanger 4 through the branch pipe.
In the process of flowing in from the point and flowing upward through the upper half thereof, the temperature is lowered by melting the frost 7 attached to the surface of the outdoor heat exchanger 4, and thereafter, the compressor 1 is passed through the four-way valve 2. Return to The liquid refrigerant condensed by heat exchange with the frost 7 accumulates in the lower part of each of the circuits 4a and 4b and in the collecting part 4d. Therefore, the refrigerant liquid does not block the path of the gas refrigerant.

In the present invention, as shown in FIG.
It is needless to say that the present invention can be applied to an outdoor heat exchanger 4 having no 4c and the collecting portion 4d, or an outdoor heat exchanger 4 having the circuits 4a and 4b arranged vertically as shown in FIG.

[0010]

According to the present invention, the hot gas bypass pipe is branched into a plurality on the downstream side of the on-off valve.
A plurality of extending the tip of the branch pipes in the vertical direction of the outdoor heat exchanger
Of each circuit mid-height hot connected to the defrosting operation in the position of the gas refrigerant mid-height upper of each circuit of the position
Since the upper half flows upward, the liquid refrigerant condensed by melting the frost adhering to the surface of the outdoor heat exchanger remains at the lower part of each circuit and does not block the path of the gas refrigerant. In addition, defrosting can be performed without raising the temperature of the liquid refrigerant as in the related art, and heat radiation from the liquid refrigerant can be prevented, so that the defrosting time can be reduced. Also, since a large amount of liquid refrigerant can be prevented from concentrating on the compressor, the durability of the compressor can be improved, and the operation of the compressor can be properly maintained. This can contribute to shortening the defrosting time.

[Brief description of the drawings]

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

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

FIG. 3 is a partial refrigerant circuit diagram showing a third embodiment of the present invention.

FIG. 4 is a refrigerant circuit diagram of a conventional air conditioner.

FIG. 5 is a partial refrigerant circuit diagram showing a state during a defrosting operation of the conventional air conditioner.

[Explanation of symbols]

 1 Compressor 4 Outdoor heat exchanger 4a, 4b circuit 8 Hot gas bypass pipe

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-240063 (JP, A) JP-A-5-296617 (JP, A) JP-A-1-116369 (JP, U) JP-A 62 127467 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) F25B 47/02 530 F25B 47/02 540

Claims (1)

(57) [Claims] 1. A an outdoor heat exchanger having a plurality of Saki <br/> Tsu preparative extending in substantially vertical direction, a high-temperature gas refrigerant discharged from the compressors to be supplied to the outdoor heat exchanger Hot gas bypass pipe and the hot gas bypass pipe
An air conditioner having an on- off valve that is opened during defrosting operation, wherein a plurality of the hot gas bypass pipes are provided downstream of the on-off valve.
And make the ends of these multiple branch pipes upward.
The high-temperature gaseous refrigerant flows through the upper half of each circuit above the intermediate height position during defrosting operation by connecting to the intermediate height position of a plurality of circuits extending in the vertical direction . An air conditioner characterized by that: