Mitsubishi Electric Corporation

Mitsubishi Electric Corpotation

Hirokuni Shiba

Fumitake Unezaki

Yohei Kato

Masanori Aoki

Naoki Wakuta

Tatsunori Sakai

Kosuke Tanaka

Takashi Okazaki

Hiroyuki Hashimoto

Hiroki Murakami

Shinya Matsushita

Shogo Tamaki

Mizuo Sakai

Satoru Yanachi

Yasuhiro Kojima

Tetsuji Saikusa

Makoto Saitou

Masato Yosomiya

Masayuki Yamamoto

Hiroaki Nakamune

Hidetoshi Muramatsu

Kiyoshi Yoshimura

Kazuya Kubo

Yasunori Mori

Kazunori Nishida

Katsuya Takeuchi

Yuto Shibao

Takanori Omori

Sou Nomoto

An air-conditioning apparatus controls a decrease in efficiency of a refrigeration cycle, and includes a suction pipe having one end connected to a suction side of a compressor and an other end connected to an evaporator, a receiver connected to a refrigerant pipe connecting the evaporator and a condenser to each other, a first bypass pipe having one end connected to the receiver and an other end connected to the suction pipe and configured to supply refrigerant from the receiver to the suction pipe, a flow control valve provided to the first bypass pipe, a heat recovery portion disposed downstream of a portion of the suction pipe connected to the first bypass pipe, and a control device configured to control an opening degree of the flow control valve based on a degree of superheat of refrigerant in the heat recovery portion.

Air-conditioning apparatus

A refrigerating and air-conditioning apparatus suppresses liquid backflow to a compressor with a simple configuration, and reduces annual power consumption. An outdoor unit and an indoor unit are connected to each other by a gas-side connecting pipe and a liquid-side connecting pipe to form a refrigerant circuit in which a compressor, a four-way valve, an indoor heat exchanger, a refrigerant heat exchanger, an expansion valve, an outdoor heat exchanger, and an accumulator are sequentially connected. The refrigerant heat exchanger transfers heat between a high-pressure-side refrigerant flowing between the expansion valve and an outdoor-unit liquid pipe connecting portion and a low-pressure-side refrigerant on an outlet side of the accumulator.

Refrigerating and air-conditioning apparatus

In a compressor shell built in an outdoor unit of an air conditioner, a compressor shell thermistor that detects a temperature of the shell is installed. Also, an outside air temperature thermistor that detects an outside air temperature is installed in an outdoor unit. The outside air temperature is compared with the compressor shell temperature, and if the shell temperature is higher than the outside air temperature, a compressor heating device is invalidated. If the shell temperature is lower than the outside air temperature, it is determined as a refrigerant collection condition, and the compressor heating device is operated. Also, if the shell temperature is higher than the outside air temperature by a certain temperature or more, the operation of the compressor heating device is stopped so that wasteful standby power is reduced, and energy of the apparatus is saved.

Air conditioner

Provided is an air-conditioning and hot water supply combination system capable of maintaining a high hot water supply capacity and achieving high efficiency even under high-temperature outside air conditions by appropriately controlling the degree of superheat and the degree of subcooling of a heat exchanger. In an air-conditioning and hot water supply combination system, when an evaporating pressure or an evaporating temperature calculated from the evaporating pressure reaches a first predetermined value or higher, the degree of superheat of a refrigerant on a low-pressure gas side of a subcooling heat exchanger or the degree of subcooling of the refrigerant on a high-pressure liquid side of the subcooling heat exchanger is controlled by the opening degree of a low-pressure bypass pressure reducing mechanism, such that the evaporating pressure or the evaporating temperature calculated from the evaporating pressure is less than or equal to the first predetermined value.

Air-conditioning and hot water supply combination system

An air-conditioning apparatus includes an outdoor air temperature sensor detecting an outdoor temperature; a compressor temperature sensor detecting a temperature of an outer wall of a compressor; a liquid-level and concentration detection sensor detecting a liquid surface level in the compressor and a concentration of a lubricant oil in a liquid in the compressor; an electric heater heating the compressor; and a controller that carries out preheating to the compressor by driving the electric heater when a detection value of the outdoor air temperature sensor is higher than or equal to a detection value of the compressor temperature sensor and, further, when the liquid surface level detected by the liquid-level and concentration detection sensor is higher than or equal to a predetermined level and the concentration of the lubricant oil in the liquid is lower than a preset minimum required concentration.

Air-conditioning apparatus utilizing compressor preheating

When a compressor is in a stopped state and an outside air temperature change rate Tah exceeds zero, a first heating operation is started, and a heating capacity of a compressor heating portion is set in a range not more than a heating capacity upper limit Pmax based on the outside air temperature change rate Tah. A remaining refrigerant liquid amount Ms condensed in the compressor that had not been evaporated is acquired based on the outside air temperature change rate Tah and the heating capacity. If the outside air temperature change rate Tah is zero or below and the remaining refrigerant liquid amount Ms exceeds zero while the compressor is in a stopped state, a second heating operation is started, the compressor heating portionis controlled based on the remaining refrigerant liquid amount Ms, and the refrigerant condensed in the compressoris evaporated.

A control device that controls a plurality of air conditioners includes a data memory section for storing performance model data representing the relationship between air conditioning capability and power consumption for each of the plurality of air conditioners. An overall air conditioning load calculating section calculates an overall load that is the sum of air conditioning loads of the plurality of air-conditioning apparatuses. An air conditioning capability allocation calculating section an air conditioning capability for each of the plurality of air conditioners on the basis of the performance model data and the overall load so that the sum of the air conditioning capability of the plurality of air conditioners is the overall load and the sum of the power consumption of the plurality of air conditioners is minimum. A control signal section sends a control signal related to the air conditioning capability to each of the plurality of air conditioners.

Air-conditioning apparatus control device and refrigerating apparatus control device

The present invention is directed to a refrigerant filling apparatus of the refrigerating and air conditioning apparatus that can automatically finish filling of a refrigerant after filling to an appropriate amount, without a need to install an extra valve except for a valve provided at a refrigerant cylinder, in between the refrigerating and air conditioning apparatus and the refrigerant cylinder, which is necessary for filling the refrigerant. The refrigerant filling apparatus of the refrigerating and air conditioning apparatus, which includes: a refrigerant circuit having a compressor, a four-way valve, an indoor side heat exchanger, a pressure reducing solenoid valve, an outdoor side heat exchanger, and an accumulator; a refrigerant cylinderconnected to the refrigerant circuit; a control unit that controls filling of the refrigerant from the refrigerant cylinderto the refrigerant circuit and decides refrigerant filling modes; and a display unit installed to the control unit and displays the refrigerant filling modes.

Refrigerant filling apparatus of refrigerating and air conditioning apparatus and refrigerant filling method of refrigerating and air conditioning apparatus

In a refrigerating air conditioning system using refrigerant such as COused in a supercritical area, a highly efficient refrigerating air conditioning system is provided by adjusting the amount of refrigerant in a radiator which contributes to the efficiency of the system stably and quickly. During heat utilizing operation, the superheat at the exit of an evaporator is controlled to a predetermined value by controlling the opening of an expansion valve provided on the upstream side of the evaporator, and an expansion valve is controlled so that the state of refrigerant in a connection pipe on the high-pressure side becomes a supercritical state. In this state, a flow rate control valve is controlled to change the density of the refrigerant stored in a refrigerant storage container and the amount of refrigerant existing in the radiator is adjusted. A target high-pressure value and a target value of the radiator exit temperature are set and the capacity of the compressor is controlled to obtain the target values, and the amount of refrigerant existing in the radiator is adjusted by the refrigerant amount adjusting circuit.

Refrigerating air conditioning system, method of controlling operation of refrigerating air conditioning system, and method of controlling amount of refrigerant in refrigerating air conditioning system

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Tokyo, Japan

Hirokuni Shiba