Abstract: A refrigeration cycle apparatus that is able to reduce the amount of refrigerant used while reducing a pressure loss in the case where a refrigerant containing at least 1,2-difluoroethylene is used is provided. In an air conditioner (1) including a refrigerant circuit (10), including a compressor (21), an outdoor heat exchanger (23), an outdoor expansion valve (24), and an indoor heat exchanger (31), and a refrigerant containing at least 1,2-difluoroethylene and sealed in the refrigerant circuit (10), the outdoor heat exchanger (23) has a heat transfer tube (23b) of which a pipe diameter is greater than or equal to 6.35 mm and less than 10.0 mm.

Abstract: A compressor includes a compression mechanism having a ring-shaped first cylinder, a first piston eccentrically rotatable in an interior of the first cylinder, a first cylinder head member disposed adjacent to one axial end of the first cylinder, a second cylinder head member disposed adjacent to an other axial end of the first cylinder, and a fastening bolt. The fastening bolt fastens the first cylinder head member, the first cylinder, and the second cylinder head member together. An end face of the first cylinder head member contacts the first cylinder, and the end face is provided with a protecting groove. The protecting groove is formed closer to a center of the first cylinder than the fastening bolt, and has a groove width smaller than a groove depth of the protecting groove.

Abstract: The refrigerant device includes a refrigerant circuit performing a refrigeration cycle in which one of the heat-source-side heat exchanger and the utilization-side heat exchanger serves as a radiator, while the other serves as an evaporator. The refrigerant circuit is filled with a refrigerant including hydrocarbon fluoride having the property of causing disproportional reaction. The refrigerant circuit includes an ejector provided with a depressurization channel, a suction channel and an ejection channel, a gas-liquid separator into which a refrigerant ejected from the ejection channel flows, an expansion mechanism depressurizing a liquid refrigerant flowing from the gas-liquid separator into the evaporator, and a suction pipe guiding a gas refrigerant of the gas-liquid separator into the compressor. As a result, it is possible to reduce the risk of disproportional reaction of the refrigerant.

Abstract: A control unit (19) that controls the operation of a refrigerant circuit (10) executes pump down operation in which a non-azeotropic refrigerant mixture is collected into a portion of the refrigerant circuit (10) within an outdoor unit (2), executes compositional ratio determination in which the compositional ratio of the non-azeotropic refrigerant mixture is determined based on the pressure and temperature of the non-azeotropic refrigerant mixture collected into the outdoor unit (2) by the pump down operation, and generates an alert when the compositional ratio of the non-azeotropic refrigerant mixture determined by the compositional ratio determination is outside an acceptable proportion range of a hydrofluorocarbon having the property of undergoing a disproportionation reaction.

Abstract: In a compressor compressing a refrigerant including hydrocarbon fluoride prone to disproportionate, provided, on a contact portion of the drive shaft and the bearing portion, is an elastic bearing portion as a heat generation suppression portion suppressing excessive heat generation due to line contact of an end edge portion of the bearing portion with the drive shaft during rotation of the drive shaft.

Abstract: As a refrigerant, a refrigerant containing a fluorocarbon having a property of causing a disproportionation reaction is used. A refrigeration apparatus includes: a refrigerant temperature detector configured to detect a discharged refrigerant temperature which is a temperature of the refrigerant that is being discharged from the compression mechanism or immediately after the discharge; and a controller configured to control the discharged refrigerant temperature detected by the refrigerant temperature detector such that the discharged refrigerant temperature is equal to or lower than a predetermined temperature Ts.

Abstract: A rotary compressor includes a cylinder having a cylinder chamber and bush groove, a piston housed in the cylinder chamber, a blade formed with the piston to separate the cylinder chamber into low and high pressure chambers, and a pair of bushes. The bushes are fitted in the bush groove with flat surfaces facing each other to hold the blade. The flat surface of at least the bush on the low-pressure side has a crowned portion starting from a position closer to the back pressure space than a swing center position, and extending toward an edge of the bush closer to the cylinder chamber. The swing center position is where a gap between the blade and the bush is constant while the piston rotates eccentrically.

Abstract: A compressor includes a compression mechanism having a ring-shaped first cylinder, a first piston eccentrically rotatable in an interior of the first cylinder, a first cylinder head member disposed adjacent to one axial end of the first cylinder, a second cylinder head member disposed adjacent to an other axial end of the first cylinder, and a fastening bolt. The fastening bolt fastens the first cylinder head member, the first cylinder, and the second cylinder head member together. An end face of the first cylinder head member contacts the first cylinder, and the end face is provided with a protecting groove. The protecting groove is formed closer to a center of the first cylinder than the fastening bolt, and has a groove width smaller than a groove depth of the protecting groove.

Abstract: A rotary compressor includes a cylinder having a cylinder chamber and bush groove, a piston housed in the cylinder chamber, a blade formed with the piston to separate the cylinder chamber into low and high pressure chambers, and a pair of bushes. The bushes are fitted in the bush groove with flat surfaces facing each other to hold the blade. The flat surface of at least the bush on the low-pressure side has a crowned portion starting from a position closer to the back pressure space than a swing center position, and extending toward an edge of the bush closer to the cylinder chamber. The swing center position is where a gap between the blade and the bush is constant while the piston rotates eccentrically.

Abstract: A combined cycle plant including a gas turbine, a heat recovery boiler for generating steam using exhaust heat of the gas turbine, and a steam turbine for feeding the steam generated by the heat recovery boiler from the heat recovery boiler through a steam system, characterized in that, the steam system is disposed so as to branch to a first steam system for introducing the steam to a first stage entrance of the steam turbine and a second steam system for introducing the steam to a stage entrance on a downstream side of the first stage of the steam turbine, and a flow rate of the steam fed to the steam turbine via the first steam system and the second steam system is adjusted on the basis of a steam flow rate generated by the heat recovery boiler.

Abstract: A refrigeration system includes a refrigerant circuit including a compressor and an expander which expands a refrigerant and generates power, for performing a refrigeration cycle. The refrigeration system includes a compressor control section and an expander control section which, when an operation stop signal is output during operation, reduces a rotational speed of the compressor and increases a rotational speed of the expander to increase the ratio of the rotational speed of the expander to the rotational speed of the compressor.

Abstract: A refrigeration system includes a refrigerant circuit including a compressor and an expander which expands a refrigerant and generates power, for performing a refrigeration cycle. The refrigeration system includes a compressor control section and an expander control section which, when an operation stop signal is output during operation, reduces a rotational speed of the compressor and increases a rotational speed of the expander to increase the ratio of the rotational speed of the expander to the rotational speed of the compressor.

Abstract: A compressor and an expander are provided in a refrigerant circuit of an air conditioner. In the compressor, refrigerator oil is supplied from an oil reservoir to a compression mechanism. In the expander, the refrigerator oil is supplied from an oil reservoir to an expansion mechanism. Internal spaces of a compressor casing and an expander casing communicate with each other through an equalizing pipe. An oil pipe connecting the compressor casing and the expander casing is provided with an oil amount adjusting valve operated on the basis of an output signal of an oil level sensor. When the oil amount adjusting valve is opened, the oil reservoir in the compressor casing and the oil reservoir in the expander casing communicate with each other to allow the refrigerator oil to flow through the oil pipe.

Abstract: In a compression/expansion unit (30) serving as a fluid machine, both of a compression mechanism (50) and an expansion mechanism (60) are contained in a single casing (31). A shaft (40) coupling the compression mechanism (50) to the expansion mechanism (60) has an oil feeding channel (90) formed therein. Refrigerating machine oil accumulated at the bottom of the casing (31) is sucked up into the oil feeding channel (90) and fed to the compression mechanism (50) and the expansion mechanism (60). The refrigerating machine oil fed to the expansion mechanism (60) is discharged from the expansion mechanism (60) together with the refrigerant after expansion, flows through the refrigerant circuit and then flows back to the compression mechanism (50) in the compression/expansion unit (30).

Abstract: A refrigerant circuit (11) of an air conditioner (10) includes a compressor (20) and an expander (30). In the compressor (20), refrigerator oil is supplied from an oil reservoir (27) to a compression mechanism (21). In the expander (30), the refrigerator oil is supplied from an oil reservoir (37) to an expansion mechanism (31). The inner pressures of the compressor casing (24) and the expander casing (34) are the high pressure and the low pressure of the refrigeration cycle, respectively. An oil adjusting valve (52) is provided in an oil pipe (42) connecting the compressor casing (24) and the expander casing (34). The oil amount adjusting valve (52) is operated on the basis of an output signal of an oil level sensor (51). When the oil amount adjusting valve (52) is opened, the refrigerator oil flows from the oil reservoir (27) in the compressor casing (24) toward the oil reservoir (37) in the expander casing (34) through the oil pipe (42).

Abstract: In a refrigerant circuit (11), a compressor (20) and an expander (30) are provided separately. An expander casing (34) is connected to a delivery pipe (26) of the compressor (20) and high pressure refrigerant passes through the inside of the expander casing (34). Therefore, the compressor casing (24) and the expander casing (34) are equalized in their internal pressure. An oil distribution pipe (41) for connection of an oil sump (27) of the compressor (20) and an oil sump (37) of the expander (30) is provided with an oil regulating valve (52). The oil regulating valve (52) is controlled in response to a signal outputted from an oil level sensor (51). When the oil regulating valve (52) is opened, the oil sump (27) within the compressor casing (24) and the oil sump (37) within the expander casing (34) fluidly communicate with each other whereby refrigeration oil travels through the oil distribution pipe (41).

Abstract: A rotary type expander is provided with two rotary mechanism parts which differ from each other in displacement volume. The outflow side of the first rotary mechanism part of small displacement volume is fluidly connected to the inflow side of the second rotary mechanism part of large displacement volume. The processes by which the volume of a first low-pressure chamber in the first rotary mechanism part decreases and the volume of a second high-pressure chamber in the second rotary mechanism part increases are respectively in sync. Refrigerant at high pressure is first introduced into a first high-pressure chamber of the first rotary mechanism part. Thereafter, this high-pressure refrigerant passes through a communicating passage and then flows by way of the first low-pressure chamber into the second high-pressure chamber while expanding. The after-expansion refrigerant flows out to an outflow port from a second low-pressure chamber of the second rotary mechanism part.

Abstract: An expander includes a cylinder at which an inflow port and an outflow port are formed, a piston eccentrically disposed in the cylinder relative to a rotational shaft to form a fluid chamber between the piston and the cylinder, and a blade dividing the fluid chamber into a high pressure side and a low pressure side. The cylinder, the piston and the blade are arranged and configured such that the expander recovers power of a fluid depressurized in the fluid chamber. The cylinder has an inner diameter Dc, the inflow port has a diameter Di, and the outflow port has a diameter Do. The relationship 0.065×Dc?Di?0.13×Dc and/or 0.065×Dc?Do?0.13×Dc is satisfied.

Abstract: A casing (31) houses therein an expansion mechanism (60) and a compression mechanism (50). The expansion mechanism (60) has a rear head (62) in which a pressure snubbing chamber (71) is provided. The pressure snubbing chamber (71) is divided by a piston (77) into an inflow/outflow chamber (72) which fluidly communicates with an inflow port (34) and a back pressure chamber (73) which fluidly communicates with the inside of the casing (31). The piston (77) is displaced in response to suction pressure variation whereby the volume of the inflow/outflow chamber (72) varies. This enables the inflow/outflow chamber (72) to directly perform supply of refrigerant to or suction of refrigerant from the inflow port (34) which is a source of pressure variation, thereby making it possible to effectively inhibit suction pressure variation.

Abstract: A positive displacement expander includes a volume change mechanism (90) for changing the volume of a first fluid chamber (72) of an expansion mechanism (60). The expansion mechanism (60) includes a first rotary mechanism (70) and a second rotary mechanism (80) each having a cylinder (71, 81) containing a rotor (75, 85). The first fluid chamber (72) of the first rotary mechanism (70) and a second fluid chamber (82) of the second rotary mechanism (80) are in fluid communication with each other to form an actuation chamber (66). Meanwhile, the first fluid chamber (72) of the first rotary mechanism (70) is smaller than the second fluid chamber (82) of the second rotary mechanism (80). The volume change mechanism (90) includes an auxiliary chamber (93) fluidly communicating with the first fluid chamber (72) and an auxiliary piston (92) for changing the volume of the auxiliary chamber (93). The auxiliary chamber (93) is in fluid communication with the first fluid chamber (72) of the first rotary mechanism (70).