Mitsubishi Electric Corporation

Mitsubishi Heavy Industries Limited

Kazuhide Yamamoto

Hiroaki Makino

Kosuke Tanaka

Takeshi Yamamoto

Tadashi Saito

Hiroki Murakami

Keiichiro Shizu

Masaya Yamaguchi

Yasuhide Hayamaru

Komei Nakajima

Koji Shukutani

Masaki Muramatsu

Hironori Nagai

An air conditioning apparatus includes an indoor unit and an outdoor unit. The outdoor unit includes a compressor that compresses a refrigerant and a motor drive apparatus that drives the compressor. The motor drive apparatus includes an inverter that converts a direct-current voltage into an alternating-current voltage and a motor that operates on the alternating-current voltage from the inverter. The motor includes six stator windings that are each openable at both ends. The motor drive apparatus further includes a connection state switching unit that includes a function of switching a connection state of the six stator windings of the motor among at least four types of connection states.

Air conditioning apparatus

Provided is a heat exchanger including a plurality of refrigerant flow paths each being a flow path into which refrigerant flows in a gas state and out of which the refrigerant flows in a liquid state, and including upstream-side flow paths allowing passage of the refrigerant in the gas state and a two-phase gas-liquid state, and at least one downstream-side flow path allowing passage of the refrigerant in the two-phase gas-liquid state and the liquid state. The heat exchanger further includes an upstream-side heat exchanger including the upstream-side flow paths, a downstream-side heat exchanger including the at least one downstream-side flow path, and at least one merger for merging the refrigerant flowing out of each of the upstream-side flow paths and causing the merged refrigerant to flow into the at least one downstream-side flow path. The upstream-side heat exchanger and the downstream-side heat exchanger are configured separately. The number of the downstream-side flow paths is smaller than the number of the upstream-side flow paths.

Heat exchanger and refrigeration cycle apparatus including the same

An air-conditioning apparatus includes a refrigeration cycle charged with non-azeotropic refrigerant mixture and refrigerating machine oil. A suction pipe which is a refrigerant pipe connecting between a suction port of a compressor and an accumulator has an end portion on the side of the accumulator extending into the accumulator. In addition, the suction pipe of the air-conditioning apparatus includes an oil return hole formed in a portion of the suction pipe located inside the accumulator at a position higher than a central portion of the accumulator. A controller of the air-conditioning apparatus controls an opening degree of a pressure reducing device so as to make quality of refrigerant flowing into the accumulator less than 1.

Air-conditioning apparatus

An apparatus includes a refrigerant circuit in which a compressor that compresses a refrigerant, an indoor-side heat exchanger serving as a radiator that exchanges heat between the refrigerant and a heating target, an expansion valve that decompresses the refrigerant by opening-degree adjustment, and an outdoor-side heat exchanger serving as an evaporator that exchanges heat between a heat-exchange target and the refrigerant are connected by pipes. The apparatus includes: an outdoor air temperature sensor that detects a temperature of outdoor air serving as the heat-exchange target; a discharge-side temperature sensor that detects a discharge temperature of the refrigerant discharged by the compressor; and a controller that, when the controller determines that a rotation speed of the compressor is a maximum and the temperature of the heat-exchange target is lower than a preset temperature, controls an opening degree of the expansion valve by using the discharge temperature.

Heat pump apparatus

In a reactor vessel () covered by cooling water (), a tubular frame () with a bottom is hung within the cooling water () while still having an air environment in the interior, and the bottom section of the frame () is disposed within the reactor vessel (), thereby achieving an air environment within the reactor vessel (). Furthermore, since repairs to the reactor vessel () are performed by using the frame () while still having the air environment in the interior, this leads to the prevention of contamination and achieves improvements in working conditions such as preventing the generation of dust and reducing decontamination work. Accordingly, repairs can be performed in an air environment without draining the cooling water () within the reactor vessel (), even in a state in which the reactor vessel () is covered by the cooling water ().

Reactor vessel repair method

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

Kazuhide Yamamoto