A refrigeration cycle device includes a compressor, an air-refrigerant heat exchanger that exchanges heat between air and refrigerant, an expansion valve decompressing the refrigerant, a heat medium-refrigerant heat exchanger that exchanges heat between a heat medium and the refrigerant, a cold-heat utilization device that utilizes cold heat of the heat medium, and a hot-heat utilization device that utilizes hot heat of the heat medium. A refrigerant flow switching valve is provided to switch between a heat-medium cooling mode of cooling the heat medium in the heat medium-refrigerant heat exchanger, and a heat-medium heating mode of heating the heat medium in the heat medium-refrigerant heat exchanger. In addition, a heat medium flow switching device is provided such that, in the heat-medium cooling mode, the heat medium circulates between the heat medium-refrigerant heat exchanger and the cold-heat utilization device, and that in the heat-medium heating mode, the heat medium circulates between the heat medium-refrigerant heat exchanger and the hot-heat utilization device.

Provided is a heat-pump system including a plurality of compressors, wherein the plurality of compressors includes a first compressor and a second compressor that compress refrigerant, an oil separator provided on a discharge side of the plurality of compressors to separate oil mixed with refrigerant compressed by the plurality of compressors, an oil separation pipe extended from the oil separator to allow the plurality of compressors to recover oil, and a compressor side oil balance pipe extended from the second compressor to allow the first compressor to recover oil stored in the second compressor.

An air conditioner and a method of controlling an air conditioner are provided. The method of controlling an air conditioner may include determining whether a low-load condition is satisfied on the basis of a number of indoor devices or a temperature of external air, performing a low-load operation of a compressor at a predetermined frequency when the low-load condition is satisfied, detecting whether an operation pressure is out of a target pressure value or range while the low-load operation is performed, and bypassing a refrigerant from the compressor to a gas/liquid separator via an injection passage when the operation pressure is out of the target pressure value or range.

A heat exchanging system exchanging heat between refrigerant and a battery includes: a compressor circulating refrigerant; a heat exchanger exchanging heat between the refrigerant and outside air; an expansion valve decompressing the refrigerant; a heat exchanger exchanging heat between the refrigerant and air-conditioning air; a heat exchanging portion connected in parallel with the heat exchanger and exchanging heat between the refrigerant and the battery; a bypass passage providing fluid communication between a path of the refrigerant between the compressor and the heat exchanger and a path of the refrigerant between the expansion valve and the heat exchanger; an expansion valve provided in the bypass passage and decompressing the refrigerant flowing through the bypass passage; and a selector valve allowing or interrupting flow of the refrigerant via the bypass passage.

A refrigeration device includes a high-voltage electrical parts group having reactors and cooled elements, a low-voltage electrical parts group, a printed wiring board with the electrical parts groups mounted, and a refrigerant jacket that uses refrigerant flowing through the refrigerant circuit to cool the cooled elements. The high-voltage electrical parts group form an interleaved power supply circuit. The cooled elements are placed in an order conforming to a power supply path of the power supply circuit. The power supply circuit has a rectifier circuit, a power factor improvement circuit, smoothing capacitors, and an inverter circuit. The power factor improvement circuit has the reactors connected to each other in parallel and diodes and switching elements serving as the cooled elements connected to each of the reactors. The reactors are placed on an opposite side of the smoothing capacitors, with the diodes and the switching elements sandwiched in between.

An air conditioner is provided that may include at least one compressor that compresses a refrigerant to a high pressure; a plurality of heat exchanger that condenses the refrigerant compressed in the at least one compressor; a plurality of outdoor valves, respectively, provided at an outlet side pipe of the plurality of heat exchangers; a gas liquid separator that separates the refrigerant into gas and liquid refrigerants and supplies the gas refrigerant to the at least one compressor; and one or more bypass devices connected to the outlet side pipe of one or more of the plurality of heat exchangers and an inlet side pipe of the gas liquid separator, the one or more bypass devices controlling a flow of the liquid refrigerant. During a cooling low load operation in which a portion of the plurality of heat exchangers is operating, a liquid refrigerant loaded into a heat exchanger of the plurality of heat exchangers, which is not operated, may flow through the one or more bypass device.

Exemplary embodiments of a cooling apparatus cool a charger for charging a storage battery upon reception of a supply of power from a power supply. Exemplary embodiments include a compressor that circulates a refrigerant, a cooling unit provided on a path along which the refrigerant flows between the heat exchanger and the expansion valve to cool the charger using the refrigerant, a refrigerant passage through which the refrigerant flows between the compressor and the heat exchanger, a refrigerant passage through which the refrigerant flows between the cooling unit and the expansion valve, and a connecting passage connecting the refrigerant passage and the refrigerant passage. When heating occurs, frost formation can be suppressed without increasing configuration complexity and power consumption.

An air conditioner system including a compressor, a condenser, an expander, an evaporator, and a bypass pipeline that guides the evaporated refrigerant from the evaporator to the condenser, wherein the bypass pipeline includes: a first bypass pipe configured to guide at least some of the evaporated refrigerant from the evaporator to the condenser; a second bypass pipe attached to the first bypass pipe to allow heat exchange between refrigerant in the condenser and refrigerant therein; and a third bypass pipe coupled to the second bypass pipe to guide the refrigerant from the second bypass pipe out of the condenser.

According to one embodiment, in a low speed drive of outdoor fans, a first flow rate adjusting valve in a main outdoor heat exchanger side is narrowed to a closing degree or a close range thereof, and an opening degree of a second flow rate adjusting valve is controlled such that a supercooling degree of refrigerant in auxiliary outdoor heat exchangers becomes constantly a target value.

A heat pump is provided that includes a first pipe in which a first refrigerant flows; a second pipe disposed at a side of the first pipe and in which a second refrigerant flows; a first heat exchanger connected with the first pipe and the second pipe and in which the first refrigerant exchanges heat with the second refrigerant; a boiler connected with the first pipe and in which the first refrigerant flows; a compressor connected with the second pipe and that compresses the second refrigerant; a second heat exchanger connected with the second pipe and in which the second refrigerant exchanges heat with outdoor air; a bypass pipe branched from first pipe and configured to exchange heat with the second heat exchanger; and a three-way valve that directs the first refrigerant to pass through the bypass pipe. When the outdoor heat exchanger operates as an evaporator, frost formation thereon may be prevented.