Mitsubishi Electric Corporation

Yasuhide Hayamaru

Kosuke Tanaka

Yusuke Tashiro

Masakazu Sato

Atsushi Kawashima

Masakazu Kondo

Naoki Nakagawa

Yusuke Adachi

Kazuya Watanabe

Hiroaki Makino

Tadashi Saito

Hiroki Murakami

Masayuki Oishi

Soshi Ikeda

Seiji Hirakawa

Hideto Nakao

Kazuhide Yamamoto

Komei Nakajima

Shohei Ishimura

Akinori Sakabe

Hironori Nagai

When a controller performs a defrosting operation in which frost on an outdoor heat exchanger is caused to be melted, the controller is configured to perform a first defrosting control in which a switching state of a switching device is set to a first state, after the controller performs the first defrosting control, perform a second defrosting control in which the switching state of the switching device is set to a second state, and after the controller performs the second defrosting control, perform a third defrosting control in which the switching state of the switching device is set to the first state.

Air-conditioning apparatus

A refrigeration cycle apparatus includes: a compressor; an indoor heat exchanger; an outdoor heat exchanger including first and second outdoor heat exchangers; a bypass flow passage causing a discharge side of the compressor to communicate with the first or second outdoor heat exchanger; a flow control valve at the bypass flow passage; and a controller performing a heating operation in which the first and second outdoor heat exchangers operate as an evaporator and the indoor heat exchanger operates as a condenser and a simultaneous heating and defrosting operation in which part of refrigerant the compressor discharges is supplied to one of the first and second outdoor heat exchangers through the bypass flow passage, the other of the outdoor heat exchangers operates as an evaporator, the indoor heat exchanger operates as a condenser, and an upper limit frequency of the compressor changes to a value higher than in the heating operation.

Refrigeration cycle apparatus

An air-conditioning apparatus includes a main circuit in which a compressor, a flow switching device, an indoor heat exchanger, a pressure reducing device, and a plurality of parallel heat exchangers connected in parallel with each other are connected by pipes, a bypass pipe, a flow control device provided to the bypass pipe and configured to adjust a flow rate of refrigerant flowing through the bypass pipe, an evaporating pressure sensor configured to measure an evaporating pressure of the refrigerant, and a controller. The air-conditioning apparatus is configured to operate in a normal heating operation mode and a heating-defrosting operation mode. When an operation associated with the normal heating operation mode is switched to an operation associated with the heating-defrosting operation mode, the controller adjusts an opening degree of the flow control device using the evaporating pressure in the parallel heat exchanger and a driving frequency of the compressor.

In an air-conditioning apparatus, a first flow passage selection device and a second flow passage selection device each are a constant-energized-type three-way valve in which a position of a main valve can be fixed in a de-energized state. When the refrigerant circuit is switched to the cooling circuit by a flow switching device, when at least one of the first flow passage selection device and the second flow passage selection device is in a de-energized state, the first flow passage selection device or the second flow passage selection device in the de-energized state is configured to output refrigerant discharged from the compressor and input therein via the flow switching device and the bypass pipe to a corresponding one of an upper-side outdoor heat exchanger and a lower-side outdoor heat exchanger.

The refrigeration cycle apparatus includes a refrigerant circuit, a controller to control the refrigerant circuit, a bypass flow path, and a flow control valve. The bypass flow path communicates between the discharge side of the compressor and the first outdoor heat exchanger or between the discharge side of the compressor and the second outdoor heat exchanger. The flow control valve is provided to the bypass flow path. The refrigerant circuit is configured to be able to perform a heating defrosting simultaneous operation. The heating defrosting simultaneous operation is an operation of supplying part of the refrigerant discharged from the compressor to one of the first outdoor heat exchanger and the second outdoor heat exchanger via the bypass flow path, causing the other of the first outdoor heat exchanger and the second outdoor heat exchanger to serve as an evaporator, and causing the indoor heat exchanger to serve as a condenser.

A refrigeration cycle apparatus includes: a first four-way valve having first to fourth ports; a second four-way valve and a third four-way valve each having fifth to eighth ports; a compressor; a discharge pipe connecting a discharge port of the compressor and the first port; a suction pipe connecting a suction port of the compressor and the second port; a first high pressure pipe connecting the discharge pipe and the fifth ports; a second high pressure pipe connecting the third port and the first high pressure pipe; a first valve provided at the first high pressure pipe; a second valve provided at the second high pressure pipe; a low pressure pipe connecting the suction pipe and the sixth ports; a first outdoor heat exchanger connected with the seventh port of the second four-way valve; a second outdoor heat exchanger connected with the seventh port of the third four-way valve; and an indoor heat exchanger connected with the fourth port.

An air conditioner includes a switching valve, a flow rate restricting portion and an on-off valve. The switching valve provided in a flow path between a compressor and an outdoor heat exchanger. The outdoor heat exchanger includes a heat exchange portion and a heat exchange portion. During heating operation, the switching valve causes a second connection port, a third connection port and a first connection port to communicate with one another. The flow rate restricting portion and the on-off valve are connected in series between an outlet and an inlet of the compressor during the heating operation, to bypass a part of refrigerant. During defrosting operation of the heat exchange portion, the switching valve is configured such that a fourth connection port and the second connection port communicate with each other, and the third connection port and the first connection port communicate with each other.

Air conditioner

An air conditioner includes a compressor, a condenser, an expansion valve, an evaporator, and a temperature detection unit. The temperature detection unit is attached to the condenser and is configured to detect a temperature of the refrigerant in the condenser. The expansion valve is configured to be capable of adjusting a flow rate per unit time of the refrigerant flowing through the expansion valve by adjusting a degree of opening of the expansion valve. The degree of opening of the expansion valve is increased when the temperature of the refrigerant detected by the temperature detection unit rises, and the degree of opening of the expansion valve is decreased when the temperature of the refrigerant detected by the temperature detection unit falls.

An air conditioning apparatus includes a flow path switching valve. An outdoor heat exchanger is divided into a first heat exchanger and a second heat exchanger. During heating operation, a refrigerant is diverted and supplied to the first heat exchanger and the second heat exchanger. During the heating operation, the flow path switching valve combines the flows of the refrigerants discharged from the first heat exchanger and the second heat exchanger, and returns the resultant refrigerant to a refrigerant inlet of a compressor. Three ports of the flow path switching valve are internally communicated with one another while being isolated from an other single port during the heating operation. Two ports of the flow path switching valve are internally communicated with each other and other two ports are internally communicated with each other during defrosting operation of the first heat exchanger or the second heat exchanger.

Air conditioning apparatus

To improve the separation efficiency of a gas-liquid separator in the gas-liquid separator and an air conditioner, the gas-liquid separator having a vessel with an inlet pipe and an outlet pipe is arranged such that an exit end section of the inlet pipe is formed to be closed or to have a gap, an expanded end section having a width greater than the diameter of that portion of the inlet pipe which crosses a container of the gas-liquid separator is provided, and that a lateral hole is formed in a side face of the expanded end section. Refrigerant vapor and refrigerant liquid are efficiently separated from each other at the expanded end section, and this improves separation efficiency of the gas-liquid separator.

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Tokyo, Japan

Yasuhide Hayamaru