The present invention relates to heat transfer compositions comprising refrigerant, lubricant and stabilizer, wherein the refrigerant comprises 39 to 45% by weight difluoromethane (HFC-32), 1 to 4% by weight pentafluoroethane (HFC-125), and 51 to 57% 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 liquid-cooling type double-sided cooler includes a first cooling portion and a second cooling portion. In the liquid-cooling type double-sided cooler, an end of the first cooling portion is formed with a first communication hole that is configured to penetrate a first cooling liquid path and an outside of the first cooling portion, and an end of the second cooling portion is formed with a second communication hole that is configured to penetrate a second cooling liquid path and an outside of the second cooling portion. In particular, the first cooling portion and the second cooling portion are positioned such that the first communication hole and the second communication hole face each other, and the first cooling liquid path and the second cooling liquid path are connected with each other.

This refrigeration apparatus (1) includes a main refrigerant circuit (2) including a positive displacement compressor (4), a condenser (6), an expansion valve (8), and an evaporator (10), through which a refrigerant circulates successively in a closed loop circulation, and a lubrication refrigerant line (18) connected to the main refrigerant circuit (2) between the condenser (6) and the expansion valve (8) or to the condenser (6), in which circulates a portion of the refrigerant of the main refrigerant circuit (2) and connected to the compressor (4) for lubrication of said compressor (4) with the refrigerant. The refrigeration apparatus includes a lubrication refrigerant tank (20) connected to the lubrication refrigerant line (18) upstream the compressor (4), the lubrication tank (20) being configured to store liquid refrigerant for lubrication of the compressor (4) and the lubrication refrigerant tank (20) comprises means (32, 34; 38, 40) to cool down the refrigerant.

A rotary compressor includes a casing, a compression mechanism housed in the casing and having a suction port, a joint pipe fixed to the casing and formed into a cylindrical shape, a suction pipe arranged inside the joint pipe and communicating with the suction port of the compression mechanism, and an accumulator including an outlet pipe connected to an inlet end of the suction pipe. The suction pipe has a large diameter portion formed on an inlet side of the suction pipe and fixed to an inner peripheral surface of the joint pipe, and a small diameter portion formed on an outlet side of the suction pipe and having a smaller outside diameter than the large diameter portion. The joint pipe is made of an iron-based material. A clearance is formed between an outer peripheral surface of the small diameter portion of the suction pipe and the inner peripheral surface of the joint pipe.

A turbo chiller that has an oil-free configuration, which reduces the frequency of maintenance and maintenance-induced release of refrigerant, and can achieve a reduced environmental impact by utilizing the characteristics of the low-pressure refrigerant R1233zd(E) that reaches negative pressure at a saturation temperature of 18° C. or lower. The turbo chiller comprises a refrigeration cycle that includes a turbo compressor, a condenser, a decompression device, and an evaporator connected in sequence via piping and is filled with a refrigerant; wherein the refrigerant is a low-pressure refrigerant R1233zd(E) refrigerant with low global warming potential and low ozone depletion potential; the turbo compressor has a direct drive configuration in which a rotating shaft of impellers is directly joined to a motor; and the rotating shaft is supported by magnetic bearings.

Methods are directed towards dynamically determining refrigerant film thickness at the rolling-element bearing and for dynamically controlling refrigerant film thickness at the rolling-element bearing. Further, an oil free chiller system is configured for dynamically determining refrigerant film thickness at the rolling-element bearing of the oil free chiller system, wherein the oil free chiller system is also configured for dynamically controlling refrigerant film thickness at the rolling-element bearing of the oil free chiller system.

Embodiments of the present invention reduce the amount of energy required to operate air-conditioners and refrigerators by providing a vapor-compression system that harnesses a low- or no-cost source of energy, namely, heat, and uses the harnessed heat to power a new kind of compressor, called a “burst compressor” and a new kind of pump, called a “vapor pump.” The heat-driven burst compressor pressurizes the refrigerant, while also providing “push and pull” vapor refrigerant to the vapor pump. The vapor pump, actuated by the high pressure refrigerant in gaseous form provided by the burst compressor, is configured to pump a combination of gaseous, vaporous and liquid refrigerant out of the receiver tank and inject that low pressure refrigerant mix into the burst compressor, where it is heated to change the state of the refrigerant to a heated, pressurized gas. Then the heated, pressurized gas is released in bursts into the other components of the vapor compression cycle. Thus, embodiments of the present invention use heat to provide cold. Because of this arrangement, vapor-compression systems constructed and arranged to operate according to embodiments of the present invention are able to provide air-conditioning and/or refrigeration much more efficiently and with much less expense than traditional vapor compression systems for air-conditioning and refrigeration.

A compressor includes: a container forming an outer shell of the compressor; a terminal portion projecting from an upper surface of the container, and configured to supply electric power to an inside of the container; a rod projecting from the upper surface of the container; a terminal cover covering the terminal portion to protect the terminal portion, and fixed to the container by the rod; and a thermal protector configured to detect a temperature of the compressor. The thermal protector is brought into contact with and fixed to a flat outer surface of the container that is formed between the terminal portion and the rod.

Provided is a refrigeration apparatus capable of appropriately supplying oil separated by oil separators to compressors according to the situation. The refrigeration apparatus includes N refrigeration units each including a compressor, an oil separator, an oil return pipe, and a heat dissipation heat exchanger; N pressure reducing valves each connected to the heat dissipation heat exchanger of a corresponding one of the N refrigeration units; and an oil return control mechanism that controls a return destination of the oil separated by the oil separators of the N refrigeration units. The oil return control mechanism includes an oil supply pipe that connects the oil return pipes of the N refrigeration units to each other, and a flow control mechanism, which controls a flowing condition of oil in the oil supply pipe, disposed in the oil supply pipe.

Provided is a refrigeration apparatus capable of appropriately supplying oil separated by oil separators to compressors according to the situation. The refrigeration apparatus includes refrigeration units each including a compressor, an oil separator, an oil return pipe, and a heat dissipation heat exchanger; a pressure reducing valve connected to the heat dissipation heat exchangers; and an oil return control mechanism controlling a return destination of the oil separated by the oil separators. The oil return control mechanism includes an oil supply pipe connecting the oil return pipes; a flow control mechanism, controlling a flowing condition of oil in the oil supply pipe, disposed in the oil supply pipe; and an ejection control mechanism, controlling an ejection condition of oil ejected from the oil separator, disposed in each oil return pipe at a position closer to the oil separator than a connection position with the oil supply pipe is.