Mitsubishi Electric Corporation

Mitsubishi Denki Kabushiki Kaisha

Osamu Morimoto

Daisuke Shimamoto

Takayoshi Honda

Kosuke Tanaka

Koji Yamashita

Makoto Saito

Takashi Matsumoto

Yuji Motomura

Koji Azuma

Hirofumi Koge

Naofumi Takenaka

Tomohiko Kasai

Hiroyuki Okano

Shinichi Wakamoto

Yoshihiro Sumida

Takanori Koike

Yoji Onaka

Tatsuo Ono

Takashi Okazaki

Masaki Toyoshima

Takeshi Hatomura

Hiroki Maruyama

Susumu Yoshimura

Fumitake Unezaki

Keisuke Takayama

Hitoshi Iijima

Hiroki Murakami

Soshi Ikeda

Shinsaku Kusube

Katsuhiro Ishimura

Shinji Murata

So Nomoto

Naomichi Tamura

Koji Nishioka

Kosuke Miyawaki

Kazuyoshi Shinozaki

Moriya Miyamoto

Hidekazu Tani

Tadashi Ariyama

Kensaku Hatanaka

Tomokazu Kawagoe

Kouji Yamashita

Hiroaki Nakamune

Mizuo Sakai

Hiroki Okazawa

Tsuyoshi Kubota

Yoshio Ueno

Kousuke Tanaka

Shigetoshi Ipposhi

Hiroshi Nakata

Satoru Yanachi

Keisuke Hokazono

Masami Imanishi

Hiroaki Hama

Keiji Harada

Katsuhiko Hayashida

Masaki Muramatsu

Hideaki Tagashira

Shinji Oka

Tomoki Inagaki

Fujio Hitomi

Junichi Ue

Kouji Azuma

Takeshi Yoshida

Hiroto Nakao

Toshihiko Honda

Seiji Inoue

Eito Saito

Akiyoshi Shiramizu

Shiro Takatani

Yasunobu Hirai

Masao Kawasaki

A header includes a plurality of branch tubes and a header manifold. If refrigerant flowing into the header manifold forms a pattern of annular flow or churn flow, tips of the branch tubes inserted into the header manifold pass through a liquid-phase portion having a thickness &#x3b4; [m] and reach a gas-phase portion. The thickness &#x3b4; [m] of the liquid-phase portion is defined as &#x3b4;=G&#xd7;(1&#x2212;x)&#xd7;D/(4&#x3c1;&#xd7;U), where G is a flow speed [kg/(ms)] of the refrigerant, x is a quality of the refrigerant, D is an inside diameter [m] of the header manifold, &#x3c1;is a liquid density [kg/m] of the refrigerant, Uis a reference apparent liquid speed [m/s] that is a maximum value within a range of variation in an apparent gas speed of the refrigerant flowing into a flow space of the header manifold. The reference apparent liquid speed U[m/s] is defined as G(1&#x2212;x)/&#x3c1;.

Air-conditioning apparatus and method of using air-conditioning apparatus

The air-conditioning apparatus includes a heat exchanger including a plurality of heat transfer tubes and a header manifold an axial fan and a refrigerant circuit. When the distance from the center of the flow space in the horizontal plane is represented on a scale of 0 to 100%, where 0% represents the center of the flow space and 100% is the position of the wall surface of the header manifold, among the plurality of branch tubes located within a height range that allows the blade to rotate, the majority of the branch tubes located at or below the height of the boss are connected to the header manifold such that their distal ends are positioned at 0 to 50% of the distance from the center, and the majority of the branch tubes located above the height of the boss are connected to the header manifold such that their distal ends are positioned at more than 50% of the distance from the center.

Air-conditioning apparatus

An air-conditioning apparatus that includes a compressor, a flow switching device, an outdoor heat exchange unit, an expansion section and an indoor heat exchanger, which are connected by pipes, in which the outdoor heat exchange unit includes a first outdoor heat exchanger, a first flow rate control device, a second outdoor heat exchanger, a second flow rate control device, a bypass pipe, the second outdoor heat exchanger, the second flow rate control device, a third flow rate control device, and a flow control device.

A refrigerant distributor branches refrigerant flowing in a refrigerant circuit into three, and includes a first bifurcate flow divider including a first pipe portion forming one inflow port, a second pipe portion and a third pipe portion forming two outflow ports communicating with the inflow port of the first pipe portion, and a second bifurcate flow divider including a fourth pipe portion forming one inflow port, and a fifth pipe portion and a sixth pipe portion forming two outflow ports communicating with the inflow port of the fourth pipe portion. The outflow port of the third pipe portion and the inflow port of the fourth pipe portion communicate with each other, and an angle &#x3b8; formed by a first plane passing through the first bifurcate flow divider and a second plane passing through the second bifurcate flow divider is between 60 and 120 degrees.

Refrigerant distributor and air-conditioning apparatus

An air-conditioning system includes a heat source side refrigerant circuit in which a heat source side heat exchanger is provided, a load side heat medium circuit in which a load side heat exchanger is provided, an intermediate heat exchanger, and a heat medium sealing. The heat medium sealing mechanism includes a supply port through which the heat medium and gas flow, the gas being more soluble in the heat medium than air, a discharge port through which the gas pushed by the heat medium is discharged, and a flow straightener that is connected to the load side heat medium circuit in such a manner that, when the gas is supplied, the gas flows from the supply port to the discharge port, and when the heat medium is supplied, the heat medium flows from the supply port to the discharge port.

Air-conditioning system and method of sealing heat medium

A refrigeration cycle apparatus includes a refrigerant circuit, through which refrigerant is circulated, including a compressor, a heat source side heat exchanger, a first expansion device, and a load side heat exchanger, a controller controlling the refrigerant circuit, and a bypass pipe that branches off from a high-pressure pipe extending from the compressor to the first expansion device and that is connected to a low-pressure pipe on a suction side of the compressor. The apparatus further includes a precooling heat exchanger that is provided in the bypass pipe and that cools the refrigerant diverted to the bypass pipe, a second expansion device that is provided in the bypass pipe and that reduces a pressure of the refrigerant cooled by the precooling heat exchanger, and a refrigerant cooler that is provided in the bypass pipe and that cools the controller with the refrigerant reduced in pressure by the second expansion device.

Refrigeration cycle apparatus

A heat exchanger includes first and second headers connected to end portions of heat transfer tubes. The second header includes a header pipe defining a flow space that communicates with the heat transfer tubes and, when the heat exchanger acts as an evaporator, allows refrigerant in a two-phase gas-liquid state to pass through the flow space into the heat transfer tubes. A bypass pipe is disposed between an entrance portion and the first header. The entrance portion has an entrance distance L between a connection end portion connected to a refrigerant pipe and a central axis of the bypass pipe. The entrance distance L of the entrance portion satisfies L&#x2265;5di, where di is an inner diameter of a flow space of the header pipe on an orthogonal plane orthogonal to a direction of refrigerant flow. The bypass pipe is inserted in the flow space of the entrance portion.

Heat exchanger and air-conditioning apparatus

A refrigeration cycle apparatus includes a refrigerant circuit, a controller, a bypass pipe, a refrigerant cooler, a second expansion device, and a controller temperature sensor. In a case where a temperature measured by the controller temperature sensor is lower than or equal to a set temperature in a state where an opening degree of the second expansion device is controlled to an instruction opening degree that is lower than or equal to a set opening degree, the controller is configured to perform foreign substance release control where the controller is configured to increase the opening degree of the second expansion device and then is configured to return the opening degree of the second expansion device to the instruction opening degree.

Refrigeration cycle apparatus having foreign substance release control

A refrigeration cycle apparatus includes a main circuit through which refrigerant circulates and in which a compressor, a condenser, a first expansion device, a centrifugal gas-liquid separator that separates refrigerant into gas refrigerant and liquid refrigerant by using centrifugal force, and an evaporator are connected by refrigerant pipes; and a bypass that returns the gas refrigerant obtained through the separation by the gas-liquid separator to a suction side of the compressor. The gas-liquid separator includes a cylindrical container, an inflow pipe, a gas outflow pipe, and a liquid outflow pipe. The main circuit includes a second expansion device provided between the liquid outflow pipe of the gas-liquid separator and the evaporator. The gas refrigerant discharged from the gas outflow pipe of the gas-liquid separator flows into the bypass, and the bypass is provided with a third expansion device.

Gas-liquid separator system for refrigeration cycle apparatus

An outdoor unit comprises a casing, a fan, a heat exchanger, an electrical component, a heat radiation member, and a duct. The casing is provided with an air outlet. The fan is disposed inside the casing and configured to blow air to the outside of the casing via the air outlet. The heat exchanger is disposed inside the casing at a position lower than the fan. The electrical component is disposed inside the casing at a position lower than the heat exchanger. The heat radiation member is connected to the electrical component inside the casing. The duct is configured to accommodate at least part of the heat radiation member inside the casing and extend in the vertical direction. An upper end of the duct is configured to protrude upward higher than a lower end of the heat exchanger.

Outdoor unit and air conditioner

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.

An air-conditioning apparatus includes: a refrigerant circuit in which a compressor, a four-way valve, a heat source-side heat exchanger, an expansion valve and a load-side heat exchanger are connected; and a controller which controls a refrigeration cycle in which refrigerant is circulated in the refrigerant circuit, to switch a flow passage for the refrigerant in accordance with which of a cooling operation, a heating operation and a defrosting operation is performed. The controller includes: a refrigeration-cycle control unit which controls the four-way valve to switch the flow passage of the refrigerant when the operation to be performed is switched from the heating operation to the defrosting operation; and a compressor control unit which sets an operation frequency of the compressor at a value lower than an operation frequency which is applied during the heating operation, when the operation is switched from the heating operation to the defrosting operation.

An air-conditioning apparatus includes a refrigeration cycle that includes an intermediate heat exchanger configured to exchange heat between a heat source side refrigerant and a heat medium different from the heat source side refrigerant. The apparatus further includes a heat medium circuit that includes at least one pump configured to circulate the heat medium in the intermediate heat exchanger. A controller in the apparatus further activates the pump to circulate the heat medium through the heat medium circuit when, during suspension of an air conditioning operation, the detected temperature of outdoor air is at or below a first predetermined temperature and a first predetermined period of time has elapsed since the pump was stopped.

Air-conditioning apparatus with temperature controlled pump operation

An air-conditioning apparatus includes a refrigeration cycle circulating refrigerant and connecting a compressor, a heat-source-side heat exchanger, one or more of load-side expansion devices, and one or more of load-side heat exchangers by refrigerant pipes, a bypass having one end connected to a discharge side of the compressor of the refrigeration cycle and the other end connected to a suction side of the compressor of the refrigeration cycle to bypass a portion of the refrigerant discharged from the compressor, a first expansion device depressurizing the refrigerant flowing through the bypass, an auxiliary heat exchanger cooling the refrigerant depressurized at the first expansion device, a second expansion device controlling a flow rate of the refrigerant flowing from the auxiliary heat exchanger to the suction side of the compressor, and a controller controlling an opening degree of the second expansion device.

An air-conditioning apparatus, including an outdoor unit including a compressor and an outdoor heat exchanger, a plurality of indoor units each including an indoor heat exchanger, and a relay unit configured to distribute refrigerant supplied from the outdoor unit to the plurality of indoor units, the relay unit including a first branch unit in which liquid-side pipes connected to the plurality of indoor units join together, and a refrigerant shutoff valve, which is configured to control bidirectional flow of the refrigerant, and is provided to the first branch unit, the number of the refrigerant shut off valve being smaller than a number of the plurality of indoor units.

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Tokyo, Japan

Osamu Morimoto