Abstract: A scroll compressor in which refrigerant gas is sucked into a hermetic container and is then compressed in a compression chamber. The scroll compressor includes an orbiting scroll including a second end plate having a second surface. The second end plate has an annular groove having an opening that opens into the second surface facing a frame and serving as a back-pressure chamber with the opening being closed by the frame, a gas communication path through which the groove communicates with the compression chamber in which the refrigerant gas is being compressed, and a first oil supply passage having a first opening that opens into at least one of a region inside the groove and a region outside the groove in the second surface and through which the refrigerating machine oil is supplied to a gap between the second surface and the frame.

Abstract: A scroll compressor in which refrigerant gas is sucked into a hermetic container and is then compressed in a compression chamber. The scroll compressor includes an orbiting scroll including a second end plate having a second surface. The second end plate has an annular groove having an opening that opens into the second surface facing a frame and serving as a back-pressure chamber with the opening being closed by the frame, a gas communication path through which the groove communicates with the compression chamber in which the refrigerant gas is being compressed, and a first oil supply passage having a first opening that opens into at least one of a region inside the groove and a region outside the groove in the second surface and through which the refrigerating machine oil is supplied to a gap between the second surface and the frame.

Abstract: A scroll compressor includes a slider including a cylindrical portion supported by a rocking bearing provided on an orbiting scroll so that it rotates freely, and a balance weight portion connected to the cylindrical portion. When a direction opposite to an eccentric direction of the orbiting scroll is a counter eccentric direction and a direction of a central axis of the rocking bearing is a Z-axis direction, the balance weight portion includes a main weight portion provided at a position distant from a center of rotation of the slider in the counter eccentric direction, and a counter-weight portion provided at a position spaced away from the orbiting scroll than a position of a center of the rocking bearing in the Z-axis direction and at a position distant from the center of rotation of the slider in the eccentric direction.

Abstract: A scroll compressor includes a fixed scroll and an orbiting scroll, which are made of materials having different strengths and which include respective scroll laps. The scroll lap of the fixed scroll and the orbiting scroll having a lower material strength has a thickness satisfying tl=2a?, where tl represents scroll lap thickness, a represents basic circle radius, and ? represents phase angle. The scroll lap of the fixed scroll and the orbiting scroll having a higher material strength has a thickness satisfying th=2a?, where th represents scroll lap thickness, a represents basic circle radius, and ? represents phase angle. The scroll lap thickness th of the fixed scroll and the orbiting scroll having the higher material strength is set to be less than the scroll lap thickness tl of the fixed scroll and the orbiting scroll having the lower material strength.

Abstract: A fluid compressor includes a closed container having an inlet, a compression mechanism including a compression chamber in which fluid flowing into the closed container through the inlet is compressed, a discharge port through which the fluid compressed in the compression chamber is allowed to flow, a discharge valve opening and closing the discharge port, and a valve retainer limiting an amount of lift of the discharge valve. The discharge valve includes a curved portion whose shape is defined by one or more curvatures. When the discharge port is closed by the discharge valve, the valve retainer and the discharge valve are spaced apart from each other.

Abstract: A scroll compressor includes a slider including a cylindrical portion supported by a rocking bearing provided on an orbiting scroll so that it rotates freely, and a balance weight portion connected to the cylindrical portion. When a direction opposite to an eccentric direction of the orbiting scroll is a counter eccentric direction and a direction of a central axis of the rocking bearing is a Z-axis direction, the balance weight portion includes a main weight portion provided at a position distant from a center of rotation of the slider in the counter eccentric direction, and a counter-weight portion provided at a position spaced away from the orbiting scroll than a position of a center of the rocking bearing in the Z-axis direction and at a position distant from the center of rotation of the slider in the eccentric direction.

Abstract: A second space communicated with a first space through communicating paths is provided on an outer circumferential side of first and second scroll bodies. Scroll end portions of the first and second scroll bodies form an inlet port configured to suck gas refrigerant into a compression chamber from the second space. Open ends of the communicating paths on a side of the second space are located at an angle larger than 0° and less than or equal to 180°, around a central axis of a rotating shaft portion, from the inlet ports in a scroll involute direction of the first scroll body and the second scroll body, respectively. Injection ports in a part of an outer circumference of the second space between the open ends and the inlet ports in a circumferential direction are configured to eject liquid refrigerant in a direction toward the inlet ports, respectively.

Abstract: A scroll compressor includes a fixed scroll and an orbiting scroll, which are made of materials having different strengths and which include respective scroll laps. The scroll lap of the fixed scroll and the orbiting scroll having a lower material strength has a thickness satisfying tl=2a?, where tl represents scroll lap thickness, a represents basic circle radius, and ? represents phase angle. The scroll lap of the fixed scroll and the orbiting scroll having a higher material strength has a thickness satisfying th=2a?, where th represents scroll lap thickness, a represents basic circle radius, and ? represents phase angle. The scroll lap thickness th of the fixed scroll and the orbiting scroll having the higher material strength is set to be less than the scroll lap thickness tl of the fixed scroll and the orbiting scroll having the lower material strength.

Abstract: A scroll compressor to compress fluid in a compression chamber formed by combining a scroll wrap of a fixed scroll and a scroll wrap of an orbiting scroll, the scroll wrap of the fixed scroll and the scroll wrap of the orbiting scroll each having a scroll inner end part having a bulb shape defined by an outer surface involute curve, an inner surface involute curve, and a plurality of arcs connecting an end of the outer surface involute curve and an end of the inner surface involute curve, at least one of the scroll inner end parts being formed in an n-tier stair-like shape in which n (n?3) number of bulb shapes are stacked on top of one another in an upright direction of the scroll wrap, the scroll compressor being configured to satisfy ?os (0)>?os (1)>?os (2)> . . . >?os (n?1) where involute roll angles of the outer surface involute curve in tiers of the stair-like shape of the scroll inner end part are ?os (0), ?os (1), ?os (2), . . .

Abstract: A second space communicated with a first space through communicating paths is provided on an outer circumferential side of first and second scroll bodies. Scroll end portions of the first and second scroll bodies form an inlet port configured to suck gas refrigerant into a compression chamber from the second space. Open ends of the communicating paths on a side of the second space are located at an angle larger than 0° and less than or equal to 180°, around a central axis of a rotating shaft portion, from the inlet ports in a scroll involute direction of the first scroll body and the second scroll body, respectively. Injection ports in a part of an outer circumference of the second space between the open ends and the inlet ports in a circumferential direction are configured to eject liquid refrigerant in a direction toward the inlet ports, respectively.

Abstract: A scroll compressor includes a stationary scroll; an orbiting scroll having a pair of first Oldham keyways on one surface thereof, the orbiting scroll defining a compression chamber in combination with the stationary scroll; a frame having a pair of second Oldham keyways and supporting the orbiting scroll; and an Oldham ring for inhibiting rotation of the orbiting scroll, the Oldham ring having a pair of first Oldham keys on one surface thereof and a pair of second Oldham keys on the other surface thereof, the first Oldham keys slidably engaging with the respective first Oldham keyways, the second Oldham keys slidably engaging with the respective second Oldham keyways.

Abstract: A fluid compressor includes a closed container having an inlet, a compression mechanism including a compression chamber in which fluid flowing into the closed container through the inlet is compressed, a discharge port through which the fluid compressed in the compression chamber is allowed to flow, a discharge valve opening and closing the discharge port, and a valve retainer limiting an amount of lift of the discharge valve. The discharge valve includes a curved portion whose shape is defined by one or more curvatures. When the discharge port is closed by the discharge valve, the valve retainer and the discharge valve are spaced apart from each other.

Abstract: A scroll compressor includes a stationary scroll; an orbiting scroll having a pair of first Oldham keyways on one surface thereof, the orbiting scroll defining a compression chamber in combination with the stationary scroll; a frame having a pair of second Oldham keyways and supporting the orbiting scroll; and an Oldham ring for inhibiting rotation of the orbiting scroll, the Oldham ring having a pair of first Oldham keys on one surface thereof and a pair of second Oldham keys on the other surface thereof, the first Oldham keys slidably engaging with the respective first Oldham keyways, the second Oldham keys slidably engaging with the respective second Oldham keyways.

Abstract: In a refrigeration cycle device, a design volume ratio, obtained by dividing a stroke volume of a sub-compressor by a stroke volume of an expander, is set to be smaller than (DE/DC)×(hE?hF)/(hB?hA). With an operating efficiency being the maximum in an operating range allowed to be set of the refrigeration cycle device, DE is a density of a refrigerant, which has flowed out from a radiator, DC is a density of the refrigerant, which has flowed out from an evaporator, hE is a specific enthalpy of the refrigerant flowing into the expander, hF is a specific enthalpy of the refrigerant, which has flowed out from the expander, hA is a specific enthalpy of the refrigerant sucked by a main compressor, and hB is a specific enthalpy of the refrigerant at an intermediate position of a compression process of the main compressor.

Abstract: A refrigeration cycle apparatus includes a refrigeration cycle formed by a first compressor, a radiator, an expander that expands a refrigerant that has passed through the radiator, and an evaporator. A bypass piping has one end connected to a discharge piping of the expander and the other end connected to a suction piping of the first compressor. A pressure sensor and a temperature sensor detect the suction pressure and suction temperature of the expander as physical quantities of the refrigerant to be sucked into the expander. A bypass valve controls the flow rate of the refrigerant. A control device determines the appropriate discharge pressure of the expander on the basis of the suction pressure and suction temperature of the expander, and opens the bypass valve when the pressure at which the expander discharges the refrigerant is higher than the determined appropriate discharge pressure.

Abstract: A scroll compressor to compress fluid in a compression chamber formed by combining a scroll wrap of a fixed scroll and a scroll wrap of an orbiting scroll, the scroll wrap of the fixed scroll and the scroll wrap of the orbiting scroll each having a scroll inner end part having a bulb shape defined by an outer surface involute curve, an inner surface involute curve, and a plurality of arcs connecting an end of the outer surface involute curve and an end of the inner surface involute curve, at least one of the scroll inner end parts being formed in an n-tier stair-like shape in which n?3) number of bulb shapes are stacked on top of one another in an upright direction of the scroll wrap, the scroll compressor being configured to satisfy ?os(0)>?os(1)>?os(2)> . . . >?os(n?1) where involute roll angles of the outer surface involute curve in tiers of the stair-like shape of the scroll inner end part are ?os(0), ?os(1), ?os(2), . . . , ?os(n?1), respectively, from a wrap tip side to a wrap root side.

Abstract: A refrigeration cycle apparatus achieves efficient operation by constantly recovering power in a wide operating range. The refrigeration cycle apparatus regulates a pressure of a high pressure side by changing either one or both of an opening degree of the intermediate-pressure bypass valve and an opening degree of the pre-expansion valve on the basis of a density ratio that is obtained from an inflow refrigerant density of the expander and an inflow refrigerant density of the sub-compressor in an actual operating state and a design volume ratio that has been expected at the time of design and that is obtained from a stroke volume of the sub-compressor, a stroke volume of the expander, and a ratio of a flow rate of the refrigerant flowing to the sub-compressor.

Abstract: Disclosed is a positive displacement expander equipped with an expansion mechanism in which power is generated using fluid energy produced while a high-pressure fluid, supplied to a plurality of expansion chambers partitioned by an orbiting scroll or a rolling piston, is being expanded and decompressed. The expander includes a communicating pipe that allows each of the expansion chambers to communicate with an expander discharge side and an opening and closing device disposed on the communicating pipe. When supply of the high-pressure fluid is stopped, the opening and closing device is opened by the time when high and low pressures between each of the expansion chambers and the expander discharge side are equalized, thus stopping the orbiting scroll or the rolling piston at a predetermined position so that an expander obtains sufficient driving force when resuming.

Abstract: In order to provide a refrigeration cycle device that is compact and efficiently utilizing an expansion machine and reduced in manufacturing cost through the use of a first compressor and second compressor driven by an expansion machine, a heat radiator and an on-off valve are disposed between the first and the second compressors and the second heat radiator is utilized irrespective of the operating mode such as the cooling or heating operation. Also, the heat transfer area ratio, which is a ratio of the heat transfer area of the second heat source side heat exchanger relative to the total heat transfer area of the heat transfer areas of said first and second heat source side heat exchangers, is set, according to the air speed distribution, within a range at which the COP is at its peak. Thus, the second heat source side heat exchanger can be utilized even during the heating operation, providing a high efficiency refrigeration cycle device.

Abstract: In a refrigeration cycle device, a design volume ratio, obtained by dividing a stroke volume of a sub-compressor by a stroke volume of an expander, is set to be smaller than (DE/DC)×hE?hF)/(hB?hA). With an operating efficiency being the maximum in an operating range allowed to be set of the refrigeration cycle device, DE is a density of a refrigerant, which has flowed out from a radiator, DC is a density of the refrigerant, which has flowed out from an evaporator, hE is a specific enthalpy of the refrigerant flowing into the expander, hF is a specific enthalpy of the refrigerant, which has flowed out from the expander, hA is a specific enthalpy of the refrigerant sucked by a main compressor, and hB is a specific enthalpy of the refrigerant at an intermediate position of a compression process of the main compressor.