Air-conditioning apparatus

Patent metadata

Field	Value
Publication number	US-10976085-B2
Application number	US-201515310875-A
Country	US
Kind code	B2
Filing date	Mar 25, 2015
Priority date	May 19, 2014
Publication date	Apr 13, 2021
Grant date	Apr 13, 2021

Abstract

In an air-conditioning apparatus in which air sucked into a casing of an outdoor unit by a fan is discharged from an upper portion of the casing, each of liquid header portions is configured to be connected with each of heat transfer tubes of a plurality of divided regions formed by dividing the outdoor heat exchangers in an up and down direction. Further, a shunt is configured to supply two-phase refrigerant, in which quality is adjusted by a gas-liquid separator, to each of the liquid header portions. To each of the liquid header portions, the shunt supplies the two-phase refrigerant of the amount corresponding to the air quantity of the divided region connected to each of the liquid header portions.

First claim

The invention claimed is:

1. An air-conditioning apparatus comprising:
a refrigeration cycle including a compressor, an indoor heat exchanger serving as a condenser or an evaporator, an expansion valve, an outdoor heat exchanger serving as an evaporator or a condenser in which gas refrigerant is cooled to liquid refrigerant, and a liquid header connected to a position that is a refrigerant inflow side of the outdoor heat exchanger when the outdoor heat exchanger serves as the evaporator;
an outdoor fan configured to supply air to the outdoor heat exchanger,
the outdoor heat exchanger being provided to a casing of an outdoor unit such that heat transfer tubes are arranged in parallel in an up and down direction,
the air, sucked into the casing of the outdoor unit by the outdoor fan, being discharged from an upper portion of the casing after exchanging heat in the outdoor heat exchanger,
the liquid header being divided into a plurality of liquid header portions in the up and down direction, the plurality of the liquid header portions include a first liquid header portion and a second liquid header portion arranged below the first liquid header portion,
each of the liquid header portions being configured to be connected with each of the heat transfer tubes of divided regions formed by dividing the outdoor heat exchanger in the up and down direction,
a first gas-liquid separator configured to separate two-phase refrigerant, flowing out of the expansion valve, into gas refrigerant and liquid refrigerant;
a bypass connecting the first gas-liquid separator and a suction side of the compressor, the bypass being configured to adjust an amount of the gas refrigerant, separated by the first gas-liquid separator, to be returned to the suction side of the compressor; and
a shunt connecting the first gas-liquid separator and each of the liquid header portions and configured to supply the two-phase refrigerant, in which quality is adjusted by the first gas-liquid separator, to each of the liquid header portions, the shunt being configured to supply, to each of the first and second liquid header portions, the two-phase refrigerant of an amount corresponding to an air quantity of the divided region connected with each of the liquid header portions,
wherein an amount of two-phase refrigerant supplied from the first liquid header portion to one of the heat transfer tubes connected to the first liquid header portion is greater than an amount of two-phase refrigerant supplied from the second liquid header portion to one of the heat transfer tubes connected to the second liquid header portion, and
wherein the shunt is configured such that, when the outdoor heat exchanger serves as a condenser, liquid refrigerants which flow out from each of the plurality of liquid header portions are combined and the combined refrigerant flows into the first gas-liquid separator.

2. The air-conditioning apparatus of claim 1 , wherein an inner diameter value D of the first liquid header portion is less than an inner diameter value for the first liquid header portion where refrigerant mass flux of the first liquid header portion is a same as a refrigerant mass flux of the second liquid header portion.

3. The air-conditioning apparatus of claim 1 , wherein
an inner diameter of one of the liquid header portions connected with a heat transfer tube of the heat transfer tubes in one of the divided regions, in which wind speed distribution is more biased, is smaller than an inner diameter of another one of the liquid header portions connected with a heat transfer tube of the heat transfer tubes in an other one of the divided regions in which wind speed distribution is less biased than the wind speed distribution of the one of the divided regions.

4. The air-conditioning apparatus of claim 1 , wherein
as an inner diameter of a flow channel of the shunt connected with each of the liquid header portions is formed to be different for each of the liquid header portions, the shunt changes the amount of the two-phase refrigerant supplied to each of the liquid header portions.

5. The air-conditioning apparatus of claim 1 , wherein
as a length of a flow channel of the shunt connected with the each of the liquid header portions is formed to be different for each of the liquid header portions, the shunt changes the amount of the two-phase refrigerant supplied to each of the liquid header portions.

6. The air-conditioning apparatus of claim 1 , further comprising:
a first bypass pipe and a flow rate control mechanism constituting the bypass, the first bypass pipe connecting the first gas-liquid separator and the suction side of the compressor and allowing the gas refrigerant separated by the first gas-liquid separator to return to the suction side of the compressor, the flow rate control mechanism adjusting a flow rate of the gas refrigerant flowing in the first bypass pipe; and
a controller configured to control the air quantity of the outdoor fan and an opening degree of the flow rate control mechanism, wherein
the controller decreases the opening degree of the flow rate control mechanism when increasing the air quantity of the outdoor fan, and increases the opening degree of the flow rate control mechanism when decreasing the air quantity of the outdoor fan.

7. The air-conditioning apparatus of claim 1 , wherein
the refrigerant flowing in the outdoor unit is a zeotropic refrigerant mixture.

8. The air-conditioning apparatus of claim 1 , further comprising
a plurality of branch pipes connecting the respective liquid header portions and the heat transfer tubes of the outdoor heat exchanger, wherein
the liquid header portion connected with the divided region in which wind speed distribution is more biased has a larger number of the branch pipes connected with a region of a same size, compared with the liquid header portion connected with the divided region in which wind speed distribution is less biased.

9. The air-conditioning apparatus of claim 1 , further comprising
a gas header connected to a position that is a refrigerant outflow side of the outdoor heat exchanger when the outdoor heat exchanger serves as an evaporator, wherein
the gas header is divided into a plurality of gas header portions in the up and down direction,
an inner diameter of a gas header portion of the plurality of gas header portions connected with a heat transfer tube of the heat transfer tubes of one of the divided regions, in which wind speed distribution is more biased, is larger than an inner diameter of a gas header portion of the plurality of gas header portions connected with a heat transfer tube of the heat transfer tubes of an other one of the divided regions in which wind speed distribution is less biased than the wind speed distribution of the one of the divided regions.

10. The air-conditioning apparatus of claim 1 , further comprising:
a gas header connected to a position that is a refrigerant outlet side of the outdoor heat exchanger when the outdoor heat exchanger serves as an evaporator; and
a plurality of refrigerant outlet pipes connecting the gas header and the suction side of the compressor when the outdoor heat exchanger serves as the evaporator, wherein
the gas header is divided into a plurality of gas header portions in the up and down direction, and
a gas header portion of the plurality of gas header portions connected with a heat transfer tube of the heat transfer tubes of one of the divided regions, in which wind speed distribution is more biased, has a larger number of the refrigerant outlet pipes, compared with a gas header portion of the plurality of gas header portions connected with a heat transfer tube of the heat transfer tubes of an other

Assignees

• Mitsubishi Electric Corp

Inventors

• Onaka Yoji
• Matsumoto Takashi
• Okano Hiroyuki
• Saito Eito
• Koge Hirofumi
• Morimoto Osamu
• Murakami Hiroki
• Nakamune Hiroaki

Classifications

• F25B41/20 Primary

  Disposition of valves, e.g. of on-off valves or flow control valves (expansion valves F25B41/31) · CPC title

• F25B1/00

  Compression machines, plants or systems with non-reversible cycle (F25B3/00, F25B5/00, F25B6/00, F25B7/00, F25B9/00 take precedence) · CPC title

• F28D1/047

  the conduits being bent, e.g. in a serpentine or zig-zag · CPC title

• F25B2600/2501

  Bypass valves · CPC title

• F25B2600/2511

  Evaporator distribution valves · CPC title