Multi-room air-conditioning apparatus

Patent metadata

Field	Value
Publication number	US-9677790-B2
Application number	US-201214396236-A
Country	US
Kind code	B2
Filing date	May 14, 2012
Priority date	May 14, 2012
Publication date	Jun 13, 2017
Grant date	Jun 13, 2017

Abstract

A multi-room air-conditioning apparatus includes an outdoor unit, a relay unit connected to an outdoor unit by first and second connection pipes, and a plurality of indoor units connected to the relay unit. The outdoor unit includes a second gas-liquid separating device provided on the suction side of the compressor. The suction side of the compressor and the second gas-liquid separating device are connected to each other by a gas-side outlet pipe and a liquid-side outlet pipe.

First claim

The invention claimed is:

1. A multi-room air-conditioning apparatus comprising:
an outdoor unit that includes at least a compressor, a switching valve, and an outdoor-unit-side heat exchanger;
a relay unit that is connected to the outdoor unit by a first connection pipe and a second connection pipe; and
a plurality of indoor units, each of which includes an indoor heat exchanger and a first flow control device and which are connected to the relay unit while being arranged in parallel,
wherein the outdoor unit includes a first route along which a refrigerant that is discharged from the compressor is guided to the second connection pipe via the switching valve and the outdoor-unit-side heat exchanger, and a second route along which the refrigerant is guided to the second connection pipe via the switching valve while bypassing the outdoor-unit-side heat exchanger, so that the refrigerant is guided in accordance with operation modes including a cooling operation mode, a heating operation mode, a cooling main operation mode, and a heating main operation mode,
wherein the relay unit includes a first gas-liquid separating device that is connected to an intervening portion of the second connection pipe, a plurality of switching units that individually connect the indoor units to one of the first connection pipe and the second connection pipe selectively, a first bypass pipe that connects the first gas-liquid separating device to each of the indoor units, a second bypass pipe that connects the first connection pipe to the first bypass pipe, a third flow control device provided to the first bypass pipe, and a second flow control device provided to the second bypass pipe, and
wherein the multi-room air-conditioning apparatus further comprises:
a second gas-liquid separating device provided between the outdoor unit and the relay unit and connected to the first connection pipe;
a gas-side outlet pipe that allows a gas refrigerant generated by gas-liquid separation performed by the second gas-liquid separating device to bypass the outdoor-unit-side heat exchanger and to flow into a refrigerant suction port of the compressor; and
a liquid-side outlet pipe that alternatively allows, depending on a switching status of the switching valve, the gas refrigerant generated by the gas-liquid separation performed by the second gas-liquid separating device to flow into the refrigerant suction port of the compressor while bypassing the outdoor-unit-side heat exchanger, or bypasses a liquid refrigerant generated by the gas-liquid separation performed by the second gas-liquid separating device to flow into the refrigerant suction port of the compressor via the outdoor-unit-side heat exchanger.

2. The multi-room air-conditioning apparatus of claim 1 ,
wherein, if the switching valve is switched such that the refrigerant discharged from the compressor is guided along the second route, the gas refrigerant generated by the gas-liquid separation performed by the second gas-liquid separating device flows into the refrigerant suction port of the compressor while bypassing the outdoor-unit-side heat exchanger, and the liquid refrigerant generated by the gas-liquid separation performed by the second gas-liquid separating device is supplied to the refrigerant suction port of the compressor via the outdoor-unit-side heat exchanger.

3. The multi-room air-conditioning apparatus of claim 1 ,
wherein, if the switching valve is switched such that the refrigerant discharged from the compressor is guided along the first route, the gas refrigerant that flows into the second gas-liquid separating device is supplied to the refrigerant suction port of the compressor via the gas-side outlet pipe and the liquid-side outlet pipe that are arranged in parallel.

4. The multi-room air-conditioning apparatus of claim 1 ,
wherein the gas-side outlet pipe is provided between an accumulator and the switching valve, and the accumulator is connected to the refrigerant suction port of the compressor.

5. The multi-room air-conditioning apparatus of claim 4 ,
wherein the gas-side outlet pipe is connected in parallel with a passage provided between the outdoor-unit-side heat exchanger and the accumulator or is inserted in the accumulator.

6. The multi-room air-conditioning apparatus of claim 1 ,
wherein the gas-side outlet pipe is connected to a suction side of the compressor.

7. The multi-room air-conditioning apparatus of claim 1 ,
wherein the second gas-liquid separating device is provided in the relay unit.

8. The multi-room air-conditioning apparatus of claim 1 ,
wherein a closed refrigerant circuit that allows the refrigerant to flow through the outdoor unit and the relay unit is provided;
wherein a closed refrigerant circuit that allows another refrigerant that is different from the refrigerant to flow through the indoor units is provided; and
wherein an intermediate heat exchanger is interposed between the two refrigerant circuits.

9. The multi-room air-conditioning apparatus of claim 1 ,
wherein the refrigerant comprises a zeotropic refrigerant mixture.

10. The multi-room air-conditioning apparatus of claim 1 further comprising:
a gas flow resistor in the gas-side outlet pipe that lowers the pressure of the gas refrigerant generated by gas-liquid separation performed by the second gas-liquid separating device, such that the gas refrigerant flowing into the refrigerant suction port of the compressor is not saturated.

Assignees

• Sakai Mizuo
• Ikeda Soshi
• Nakamune Hiroaki
• Yoshimura Susumu
• Takenaka Naofumi
• Okazawa Hiroki
• Hokazono Keisuke
• Morimoto Osamu
• Mitsubishi Electric Corp

Inventors

• Sakai Mizuo
• Ikeda Soshi
• Nakamune Hiroaki
• Yoshimura Susumu
• Takenaka Naofumi
• Okazawa Hiroki
• Hokazono Keisuke
• Morimoto Osamu

Classifications

• F25B25/005

  using primary and secondary systems · CPC title

• F25B13/00 Primary

  Compression machines, plants or systems, with reversible cycle (defrosting cycles F25B47/02) · CPC title

• F25B2313/0272

  using bridge circuits of one-way valves · CPC title

• F25B2313/006

  two pipes connecting the outdoor side to the indoor side with multiple indoor units · CPC title

• F25B2400/23

  Separators · CPC title