A cryogenic refrigerator includes a cylinder, a displacer configured to be moved back and forth in the cylinder by a drive unit, an inlet valve configured to be opened in supplying a refrigerant gas into the cylinder, an exhaust valve configured to be opened in exhausting the refrigerant gas from the cylinder, and an expansion space formed in the cylinder and configured to generate a cooling by expanding the refrigerant gas caused by back and forth movement of the displacer. A moving speed of the displacer in the vicinity of a bottom dead center is set to be faster than the moving speed of the displacer in the vicinity of a top dead center.

A cryogenic refrigerator includes a cylinder, a displacer configured to be moved back and forth in the cylinder by a drive unit, an inlet valve configured to be opened in supplying a refrigerant gas into the cylinder, an exhaust valve configured to be opened in exhausting the refrigerant gas from the cylinder, and an expansion space formed in the cylinder and configured to generate a cooling by expanding the refrigerant gas caused by back and forth movement of the displacer. A moving speed of the displacer in the vicinity of a bottom dead center is set to be faster than the moving speed of the displacer in the vicinity of a top dead center.

A method of controlling injection into a compressor in a refrigeration cycle is described. A refrigeration cycle may comprise at least an economizer heat exchanger, a heat rejection heat exchanger, a first expansion device, and a compressor. A discharge port of the compressor is connected to the heat rejection heat exchanger via a discharge line and an injection port of the compressor is connected to the means for compressing. The economizer heat exchanger comprises a first path having an input connected to the heat rejection heat exchanger and an output connected to the first expansion device, and a second path having an input connected to the heat rejection heat exchanger via an economizer valve and an output connected to the injection port of the compressor via an injection line. The economizer valve is regulated based on a superheat level of the refrigerant in the economizer heat exchanger.

A system includes a flash tank and a thermal storage tank. The flash tank is configured to store refrigerant and discharge a flash gas. The thermal storage tank is fluidically coupled to the flash tank and configured, when a power outage is determined to be occurring, to receive at least a portion of the flash gas from the flash tank, and remove heat from the flash gas. When a power outage is determined not to be occurring, the thermal storage tank directs refrigerant to a compressor.

An air-conditioning apparatus is able to ensure an appropriate flow rate of refrigerant and an appropriate amount of oil returned to a compressor that match operation conditions regardless of an operating state of a refrigerant circuit and a change in an operation condition. The air-conditioning apparatus includes: a first detector configured to detect a refrigerant temperature within an accumulator; a storage unit configured to store information regarding a two-layer separation temperature of refrigerant and refrigerating machine oil; a determiner configured to compare the refrigerant temperature with the two-layer separation temperature and determine a two-layer separation state of the refrigerant and the refrigerating machine oil; a second detector configured to detect a state of the refrigerant sucked by the compressor; and a control unit configured to adjust an opening degree of a flow control valve on the basis of the two-layer separation state and a state of the sucked refrigerant.

The disclosure relates to apparatuses and methods for indicating status of multi-phase vacuum-assisted recovery of refrigerant from a vehicle. One apparatus for multi-phase vacuum-assisted recovery of refrigerant from a vehicle includes a compressor that removes refrigerant from the vehicle during a first phase and a second phase of a recovery process. The apparatus also includes a vacuum pump to assist the compressor in the removal of refrigerant from the vehicle during a second stage of the recovery process. Further, the vacuum pump is fluidly connected in series with the compressor during the second phase of the recovery process. The apparatus additionally includes one or more status lights and at least one processor to determine a status of the recovery process. At least one of the status lights is illuminated to represent a status of the recovery process, and at least one is visible from 360 degrees around the apparatus.

An air conditioning system includes a storage medium and an air conditioning system, for a three-pipe air conditioning system, the three-pipe air conditioning system includes a compressor, an outdoor heat exchanger, an indoor heat exchanger, a gas-liquid separator, a first pipeline, a second pipeline and a third pipeline; the oil return control method comprises the following steps: controlling the compressor to operate at a first frequency in a refrigerating mode; judging whether the operation duration of the refrigerating mode reaches a first preset time or not; if so, the air conditioning system enters an oil return state, and the compressor, the third pipeline, the second pipeline and the gas-liquid separator are controlled to be communicated in sequence to form a refrigerant circulation loop.

A refrigeration cycle apparatus includes refrigerant circuits in which a high pressure shell compressor, an outdoor heat exchanger, an expansion valve, and an indoor heat exchanger are connected; a mixed refrigerant made up of a mixture of 1,1,2-trifluoroethylene, difluoromethane, and 2,3,3,3-tetrafluoropropene and configured to circulate through the refrigerant circuits, the mixed refrigerant containing less than 50 wt % of 1,2,2-trifluoroetylene and a mixing ratio of difluoromethane being between 0.7 times and two times (both inclusive) that of 1,2,2-trifluoroetylene in terms of weight ratio, in a state before the mixed refrigerant is enclosed in the refrigerant circuits; and a refrigerating machine oil enclosed in the refrigerant circuits and prepared such that difluoromethane is least soluble in the refrigerating machine oil.

The present invention relates to heat transfer compositions comprising refrigerant, lubricant and stabilizer, wherein the refrigerant comprises about 49% by weight difluoromethane (HFC-32), about 11.5% by weight pentafluoroethane (HFC-125), and about 39.5% by weight trifluoroiodomethane (CF.sub.3I), and wherein said lubricant comprises polyol ester (POE) lubricant and/or polyvinyl ether (PVE) lubricant, and wherein said stabilizer comprises an alkylated naphthalene and optionally but preferably an acid depleting moiety.

A scroll compressor includes a shell that is cylindrical, a fixed scroll fixed to an inner wall of the shell, an orbiting scroll that faces the fixed scroll, a frame fixed to the inner wall of the shell and that supports the orbiting scroll, and a heat source device provided on an outside of the shell and between the fixed scroll and the frame and configured to heat or cool the shell from the outside.