An oil supply system for a compressor according to an embodiment includes an oil separator connected to a discharge pipe of the compressor, an oil tank for receiving oil from an oil sump of the oil separator, an oil pipe disposed between the oil separator and the oil tank, a pressure reducing valve disposed on the oil pipe, an oil supply pipe for supplying the oil to an oil line for supplying the oil to the compressor from an oil sump of the oil tank, and an agitator disposed on the oil pipe.

To provide a working medium for heat cycle which has less influence over the ozone layer, which has less influence over global warming and which provides a heat cycle system excellent in the cycle performance (the efficiency and the capacity), and a heat cycle system excellent in the cycle performance (the efficiency and the capacity). A working medium for heat cycle comprising 1,2-difluoroethylene is employed for a heat cycle system (such as a Rankine cycle system, a heat pump cycle system, a refrigerating cycle system 10 or a heat transport system).

A hydrogen cooling apparatus according to an embodiment includes: a binary refrigeration unit including a high-temperature-side refrigerator and a low-temperature-side refrigerator; and a hydrogen-cooling-fluid circulation unit. The binary refrigeration unit cools a hydrogen cooling fluid circulated by the hydrogen-cooling-fluid circulation unit by means of a low-temperature-side evaporator of the low-temperature-side refrigerator. The high-temperature-side refrigerator includes: a high-temperature-side refrigeration circuit; and a high-temperature-side bypass circuit including: a high-temperature-side bypass flow path that extends from a part, which is downstream of a high-temperature-side compressor and upstream of a high-temperature-side condenser in the high-temperature-side refrigeration circuit, to a part, which is downstream of a high-temperature-side expansion valve and upstream of a high-temperature-side evaporator in the high-temperature-side refrigeration circuit; and a high-temperature-side opening and closing valve provided on the high-temperature-side bypass flow path. The high-temperature-side refrigerator opens the high-temperature-side opening and closing valve when a high-temperature-side refrigerant has an abnormal pressure.

An ejector-based cryogenic refrigeration system for cold energy recovery includes a first cryogenic refrigeration loop connected by a helium compressor and a cryogenic refrigerator and a second cryogenic refrigeration loop connected by the helium compressor, a regenerator, an ejector, a cold head of the cryogenic refrigerator, an end to be cooled and a pressure regulating valve. The cryogenic refrigerator is separated from the end to be cooled. The cryogenic refrigerator and the cryogenic helium cooling loop share a helium compressor, which improves the utilization efficiency of the device and reduces the cost. The ejector allows a part of fluids to circulate in the cryogenic loop, so as to maintain a required cryogenic condition, recover the pressure of the fluids, reduce the gas flowing though the compressor loop, and thus reduce the power consumption of the compressor.

A refrigeration cycle apparatus (1) is capable of performing a refrigeration cycle using a small-GWP refrigerant. The refrigeration cycle apparatus (1) includes a refrigerant circuit (10) and a refrigerant enclosed in the refrigerant circuit (10). The refrigerant circuit includes a compressor (21), a condenser (23), a decompressing section (24), and an evaporator (31). The refrigerant contains at least 1,2-difluoroethylene.

A compact heat exchanger unit within an air conditioning apparatus for a vehicle, and a condenser region for the condensation of refrigerant is formed as a heat exchanging surface, and a high-pressure-refrigerant collector region as a refrigerant collector is formed in the integrated form as a plate packet of a heat exchanger within a plate heat exchanger.

A circulating loop for transporting refrigeration to a remote location is connected serially between a Gifford-McMahon (GM) or GM type Pulse Tube cold head and the compressor. Either high pressure gas from the compressor can flow through the remote heat station before returning to the cold head or low pressure gas can flow from the cold head to the remote heat station before returning to the compressor. A first fraction of gas, which may include all of the gas at ambient temperature, enters a counter-flow heat exchanger, is cooled by the cold head, flows to the remote load, and then returns to ambient temperature as it flows through the counter-flow heat exchanger. The high or low pressure line may have a circulation control valve that diverts a second fraction of gas to flow directly between the cold head and compressor. A controller adjusts the circulation control valve to optimize the cooling of the load.

A refrigeration cycle apparatus includes a refrigerant circuit and allows refrigerant containing a halogenated hydrocarbon to circulate in the refrigerant circuit. The halogenated hydrocarbon has at least one of C—I bond, C—Br bond, and C—CI bond and has no double bond, at least one of members constituting the refrigerant circuit is a copper-containing member, and at least a part of a surface of the copper-containing member does not contact the refrigerant.

A system includes a compressor for increasing the pressure of a refrigerant; a condenser heat exchanger arranged downstream of the compressor for receiving a high pressure refrigerant output from the compressor and for transferring heat from the high pressure refrigerant to a source of water; an expansion device for reducing the pressure of a refrigerant; and an evaporator heat exchanger for extracting heat from ambient air. The evaporator heat exchanger includes a first tube bank having a first inlet arranged to receive a high pressure refrigerant output from the condenser and a first outlet fluidly coupled to the expansion device; and a second tube bank having a second inlet arranged to receive a low pressure refrigerant output from the expansion device, and a second outlet fluidly coupled to an inlet of the compressor.

In a refrigeration cycle apparatus, a refrigerant pipe is connected to a compressor, a first heat exchanger, an expansion valve, a second heat exchanger, a heat absorber, and the compressor sequentially in this order. R290 is used as refrigerant flowing through the refrigerant pipe. The heat absorber is provided in a portion of the refrigerant pipe between the compressor and the first heat exchanger or the second heat exchanger serving as an evaporator. The heat absorber is disposed in contact with an electric component. A branch pipe is connected in parallel with the portion provided with the heat absorber in the refrigerant pipe. The branch pipe is provided with a flow rate regulating valve.