Abstract: A hot gas bypass circuit that connects a discharge side of the compressor and a portion between the heat source side heat exchanger and the expansion valve, an on-off valve that opens and closes a channel of the hot gas bypass circuit, and a control device performing control to select one of hot gas bypass defrosting and reverse cycle defrosting according to a frosting amount on the heat source side heat exchanger and perform defrosting. The control device controls to open the on-off valve of the hot gas bypass circuit such that a part of a refrigerant discharged from the compressor is supplied to the heat source side heat exchanger via the hot gas bypass circuit and, the control device switches switch the four-way valve such that the refrigerant discharged from the compressor is supplied to the heat source side heat exchanger after passing through the four-way valve.

Abstract: The air conditioner has: an outdoor heat exchanger that exchanges heat between the air and a refrigerant flowing in the interior of this heat exchanger; an outdoor fan that blows air into the outdoor heat exchanger; an outdoor fan motor that rotationally drives the outdoor fan; an outdoor fan inverter that supplies a desired current to the outdoor fan motor; a current detector that detects the current flowing in the outdoor fan motor; and a control unit that controls the outdoor fan inverter such that the rotational frequency of the outdoor fan motor reaches a target rotational frequency. The control unit starts a defrosting operation of the outdoor heat exchanger on the basis of a detection value from the current detector during the heating operation.

Abstract: The present invention provides a heat exchanger having a heat exchanging portion HE including a plurality of paths through which a refrigerant flows and a plurality of columns of fin plate that exchange heat between the refrigerant and air, wherein, in a case where the heat exchanging portion functions as a condenser, the refrigerant is flown from a header into the heat exchanging portion HE via the plurality of paths, every two paths of the plurality of paths merge into one single path by branching/merging pipes after the refrigerant has flown through one fin plate, before the refrigerant flows through the other fin plate so as to flow out of the heat exchanging portion HE, wherein a difference in height between the highest path and the lowest path in a vertical direction is set equal to or less than half of a height of the heat exchanging portion HE.

Abstract: Provided is an air conditioner which comprises multiple outdoor units, the air conditioner being configured so that, with the use of a low cost configuration, required refrigeration machine oil is supplied to all the outdoor units through refrigerant piping and so that the air conditioner has increased reliability. An air conditioner is provided with multiple indoor units and with four outdoor units which are connected to the multiple indoor units through refrigerant piping. A line of first refrigerant piping leading from the multiple indoor units is branched into two lines of second refrigerant piping, each of the two lines of second refrigerant piping is branched into two lines of third refrigerant piping, and the four lines of third refrigerant piping are respectively connected to the four outdoor units.

Abstract: A refrigerating device including a refrigerating cycle including a plurality of compressors driven by motors, the plurality of compressors comprising a variable speed compressor which can be controlled in capacity and a constant speed compressor which is driven by a motor of which rotor core comprising a cage type conductor and permanent magnets.

Abstract: A refrigerating device including a refrigerating cycle including a plurality of compressors driven by motors, the plurality of compressors comprising a variable speed compressor which can be controlled in capacity and a constant speed compressor which is driven by a motor of which rotor core comprising a cage type conductor and permanent magnets.

Abstract: A refrigerating device including a refrigerating cycle including a plurality of compressors driven by motors, the plurality of compressors comprising a variable speed compressor which can be controlled in capacity and a constant speed compressor which is driven by a motor of which rotor core comprising a cage type conductor and permanent magnets.

Abstract: A refrigerating device including a refrigerating cycle including a plurality of compressors driven by motors, the plurality of compressors comprising a variable speed compressor which can be controlled in capacity and a constant speed compressor which is driven by a motor of which rotor core comprising a cage type conductor and permanent magnets.

Abstract: An air-conditioner, an outdoor unit and an refrigeration device each using a refrigeration cycle which can reduce power consumption so as to be highly efficient, which can be operated by a commercially available power source, and which is highly reliable. An air-conditioner comprises a motor and a refrigeration cycle including a compressor driven by the motor, an outdoor heat-exchanger and an indoor heat-exchanger, the motor being located in a motor chamber within a closed container, and refrigerant gas in the refrigeration cycle flows through the motor chamber, wherein the motor has a core of a rotor in which a cage type conductor and permanent magnets magnetized in bipolar state are embedded, and said motor is driven by a commercially available electric power source.

Abstract: An air-conditioner, an outdoor unit and an refrigeration device each using a refrigeration cycle which can reduce power consumption so as to be highly efficient, which can be operated by a commercially available power source, and which is highly reliable. An air-conditioner comprises a motor and a refrigeration cycle including a compressor driven by the motor, an outdoor heat-exchanger and an indoor heat-exchanger, the motor being located in a motor chamber within a closed container, and refrigerant gas in the refrigeration cycle flows through the motor chamber, wherein the motor has a core of a rotor in which a cage type conductor and permanent magnets magnetized in bipolar state are embedded, and said motor is driven by a commercially available electric power source.

Abstract: An air-conditioner, an outdoor unit and an refrigeration device each using a refrigeration cycle which can reduce power consumption so as to be highly efficient, which can be operated by a commercially available power source, and which is highly reliable. An air-conditioner comprises a motor and a refrigeration cycle including a compressor driven by the motor, an outdoor heat-exchanger and an indoor heat-exchanger, the motor being located in a motor chamber within a closed container, and refrigerant gas in the refrigeration cycle flows through the motor chamber, wherein the motor has a core of a rotor in which a cage type conductor and permanent magnets magnetized in bipolar state are embedded, and said motor is driven by a commercially available electric power source.

Abstract: An air-conditioner, an outdoor unit and an refrigeration device each using a refrigeration cycle which can reduce power consumption so as to be highly efficient, which can be operated by a commercially available power source, and which is highly reliable. An air-conditioner comprises a motor and a refrigeration cycle including a compressor driven by the motor, an outdoor heat-exchanger and an indoor heat-exchanger, the motor being located in a motor chamber within a closed container, and refrigerant gas in the refrigeration cycle flows through the motor chamber, wherein the motor has a core of a rotor in which a cage type conductor and permanent magnets magnetized in bipolar state are embedded, and said motor is driven by a commercially available electric power source.

Abstract: An air-conditioner, an outdoor unit and an refrigeration device each using a refrigeration cycle which can reduce power consumption so as to be highly efficient, which can be operated by a commercially available power source, and which is highly reliable. An air-conditioner comprises a motor and a refrigeration cycle including a compressor driven by the motor, an outdoor heat-exchanger and an indoor heat-exchanger, the motor being located in a motor chamber within a closed container, and refrigerant gas in the refrigeration cycle flows through the motor chamber, wherein the motor has a core of a rotor in which a cage type conductor and permanent magnets magnetized in bipolar state are embedded, and said motor is driven by a commercially available electric power source.

Abstract: In a refrigerating cycle in which a constant speed type compressor, an indoor heat exchanger and an outdoor heat exchanger are connected one by one by means of piping, a receiver is provided between the indoor and outdoor heat exchangers, and no capacity control mechanism is provided for the compressor, a gas-liquid flow rate regulating device is associated with the receiver for regulating at least either of liquid flow rate and gas flow rate of a cooling fluid which flows into and out of the receiver. This causes a quantity of excess refrigerant stored in the receiver to change to thereby vary an effective quantity of refrigerant circulating through the refrigerating cycle.

Abstract: A refrigeration cycle comprises a compressor, an indoor heat exchange, an outdoor heat exchanger, a liquid receiver; and a pressure reducer connected in series to form a closed loop. The liquid receiver and the pressure reducer connected in series are connected between the indoor heat exchanger and said outdoor heat exchanger. A non-azeotropic mixture refrigerant comprising at least two kinds of refrigerant of different boiling temperatures mixed together is charged in and circulated through the refrigeration cycle. The mixing ratio of the azeotropic mixture refrigerant circulated thorough the refrigeration cycle is controlled substantially constant.

Abstract: A refrigerating system having a refrigerating cycle constructed by connecting an accumulator, a refrigerant compressor, a four-way valve, an outdoor unit heat exchanger, an outdoor unit expander, a receiver, an indoor unit expander and an indoor unit heat exchanger sequentially by pipes. Normally, excessive refrigerant is stored in the receiver and when it becomes necessary to raise a ratio of lower boiling point refrigerants, a flow amount of the refrigerant is decreased by restricting the outdoor unit expander during the cooling operation or by restricting the indoor unit expander during the heating operation to move the excessive refrigerant within the receiver to the accumulator. Thereby, the composition of the refrigerant circulating within the refrigerating system using non-azeotrophic refrigerant mixtures may be changed without using a complicated system structure or control method thereof and the capacity of the refrigerating cycle may be changed.

Abstract: A refrigeration cycle comprises a compressor, an indoor heat exchanger, an outdoor heat exchanger, a liquid receiver; and a pressure reducer connected in series to form a closed loop. The liquid receiver and the pressure reducer connected in series are connected between the indoor heat exchanger and said outdoor heat exchanger. A non-azeotropic mixture refrigerant comprising at least two kinds of refrigerant of different boiling temperatures mixed together is charged in and circulated through the refrigeration cycle. The mixing ratio of the azeotropic mixture refrigerant circulated thorough the refrigeration cycle is controlled substantially constant.

Abstract: A mixed-refrigerant comprising two or more types of refrigerants having different boiling points is enclosed in a refrigerating cycle and a capacitance sensor is used as a device for detecting a composition of the mixed-refrigerant. The electrostatic capacitance sensor is disposed in an evaporation portion of the refrigerating cycle. The refrigerating cycle has a refrigerant composition calculating device for calculating a composition of the refrigerant in the refrigerating cycle in accordance with an output signal from the capacitance sensor and an adequate composition judging device for judging whether or not the composition of the mixed-refrigerant circulating in the refrigerating cycle is in an adequate state in accordance with an output signal from the refrigerant composition calculating device.

Abstract: The composition of a refrigerant in a refrigeration cycle is detected, so that the refrigeration cycle is controlled by a control method in accordance with the detected composition. A control target value is set in accordance with the detected composition, and when the composition is varied, the control target is changed in accordance with that variation. As a result, even when the refrigerant composition is varied, the refrigeration cycle can be operated stably. The refrigeration cycle uses a non-azeotrope refrigerant, and includes a device for detecting the composition of a non-azeotrope refrigerant; a device for detecting the operating state of the refrigeration cycle, i.e.

Abstract: A heat-pump device indicates a weight of inappropriate amount of refrigerant in a heat-pump cycle by comparing an actual amount of refrigerant in the heat-pump cycle with an appropriate amount thereof, operates in accordance with a refrigerant amount judging operational mode when the actual amount of refrigerant is measured, and includes a judging device for judging the amount of refrigerant in the heat-pump cycle on the basis of a temperature of refrigerant at a condensor side and at least one information showing an operational condition of the heat-pump cycle.