Mitsubishi Electric Corporation

Mitsubishi Denki Kabushiki Kaisha

Kengo Takahashi

Kazuki Okada

Shinichi Uchino

Yoshihiro Takahashi

Fumitake Unezaki

Mamoru Hamada

Hirokazu Minamisako

Yasuyuki Arai

Takahiro Ushijima

Masaharu Miwa

Yoshiaki Kuwahara

Tetsuji Uchiyama

Ryo Oya

In a heat pump apparatus, it is aimed to enhance efficiency of a defrost operation by reducing a loss of heat radiation during the defrost operation and reducing a compressor input during the defrost operation. The heat pump apparatus includes a main refrigerant circuit in which a compressor, a first heat exchanger, an expansion mechanism, and a second heat exchanger are connected sequentially, and also includes a bypass circuit including an on-off valve and providing a connection by bypassing the expansion mechanism. The main refrigerant circuit includes a four-way valve that switches between a heating operation and the defrost operation by switching an order in which the refrigerant circulates through the main refrigerant circuit. The main refrigerant circuit also includes a first temperature detection unit and a second temperature detection unit. Based on values detected by these temperature detection units, a degree of superheat of the first heat exchanger during the defrost operation is computed. When the heating operation is switched to the defrost operation, the heat pump apparatus increases a circulation amount of the refrigerant circulating through the refrigerant circuit by opening the on-off valve, and also controls an operation frequency of the compressor such that the degree of superheat is at a predetermined target value.

Heat pump apparatus

When using a plurality of heaters such as heat pump units, capacity is properly distributed according to the required capacity, thereby enabling highly efficient operation of a hot water system. To achieve this, a control apparatus determines the heating capacity of each of the heat pump units in a way that the total heating capacity of the heat pump units reaches the heating capacity required in the hot water system as a whole, and further in a way that the total COP (coefficient of performance) of the heat pump units satisfies predetermined condition. The control apparatus controls each of regulating valves in a way that the heating capacity of each of the heat pump units reaches the above determined heating capacity.

Fluid heating system, fluid heating method, fluid heating control system, control apparatus, and control method

A heat pump apparatus includes a refrigerant circuit in which a compressor, a condenser, expansion means, and an evaporator are serially connected. Condensation temperature detection means that detects a saturation temperature of the condenser, and evaporation temperature detection means that detects the saturation temperature of the evaporator are provided. Operation efficiency is estimated by a value obtained by dividing heating ability estimated from a detection value of the condensation temperature detection means by a difference between a detection value of condensation temperature detection means and that of evaporation temperature detection means or dissipation power estimated by the difference.

A heat pump type hot water supply outdoor apparatus, in a compressor, a water heat exchanger, a first expansion valve, a medium pressure receiver, a second expansion valve, and an air heat exchanger are connected circularly, has an injection circuit, which is a bypass for a part of the refrigerant between the medium pressure receiver and the second pressure reduction unit, to inject the part of refrigerant into a compression chamber of the compressor, and has a third expansion valve and an internal heat exchanger for carrying out heat exchange between the refrigerant whose pressure is reduced by the third expansion valve and the refrigerant between the medium pressure receiver and the second expansion valve, a pressure detection sensor for detecting a condensing pressure, and a controller for starting an injection control by the third expansion valve at the time when the condensing pressure detected by the pressure sensor or the condensing temperature calculated from the condensing pressure becomes a first predetermined value or more and stopping the injection control at the time when the condensing pressure or the condensing temperature becomes a second predetermined value which is smaller than the first predetermined value, or less. With this arrangement, an appropriate injection control can be realized and a high hot water supply/heating capability operation can be carried out.

Heat pump type hot water supply outdoor apparatus

An air condition includes a suction grill for sucking the air in a room, a front panel including an inlet port for sucking the air from the suction grill inside and a blowout port for blowing the air out into the room, a heat exchanger for heat exchange of the air, and a blower for circulating the air, wherein a concave air passage for room temperature detection is formed on the front face of the front panel, and an air suction port for sucking air for room temperature detection is formed in suction grill at an opposite part to air passage.

Air conditioner

An air conditioner includes suction grill for sucking the air in a room, a front panel including an inlet port for sucking the air from the suction grill inside and a blowout port for blowing the air out into the room, a heat exchanger for working heat exchange of the air, and a blower for circulating the air, wherein a concave air passage for room temperature detection is formed on the front face of the front panel, and an air suction port for sucking air for room temperature detection is formed in suction grill at an opposite part to air passage.

Growing community of inventors

Tokyo, Japan

Kengo Takahashi