Abstract: A rotary compressor uses a freon without containing chlorine ions and uses polyol ester as a lubricant or plyvinyl ether as a base oil for providing a highly reliable rotary compressor, and for preventing abnormal abrasion. The rotary compressor has a roller and a vane sliding contact with an outer circumference of the roller. A sliding contact portion between the vane and the roller is formed with a curvature Rv, and satisfies T<Rv<Rr, wherein T is the thickness of the vane and Rr is the curvature of the outer circumference of the roller.

Abstract: A refrigerant compressor is configured such that a compressor unit is installed in a hermetically sealed container, an HFC type refrigerant or a mixture thereof and a refrigerator oil having compatibility with the refrigerant are charged into the hermetically sealed container, and the refrigerator oil essentially comprises a polyvinyl ether type compound having structural units represented by the following general formula (1): ##STR1## wherein n is an integral number in the range of 1 or more, R1 to R3 are each a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms and may be the same or different, R4 is an alkyl group having 1 to 4 carbon atoms, and units in which R4 is an alkyl group having 1 to 2 carbon atoms are 40 to 100% and units in which R4 is an alkyl group having 3 to 4 carbon atoms are 0 to 60%.

Abstract: A refrigerant compressor is configured such that a compressor unit is installed in a hermetically sealed container, an HFC type refrigerant or a mixture thereof and a refrigerator oil having compatibility with the refrigerant are charged into the hermetically sealed container, and the refrigerator oil essentially comprises a polyvinyl ether type compound having structural units represented by the following general formula (1): ##STR1## wherein n is an integral number in the range of 1 or more, R1 to R3 are each a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms and may be the same or different, R4 is an alkyl group having 1 to 4 carbon atoms, and units in which R4 is an alkyl group having 1 to 2 carbon atoms are 40 to 100% and units in which R4 is an alkyl group having 3 to 4 carbon atoms are 0 to 60%.

Abstract: There are provided a highly durable and efficient refrigerating apparatus and a lubricating oil composition that uses an HFC type refrigerant and is still free from the problem of thermal hydrolysis of polyol-ester type oil and resulting generation of carboxylic acid and sludge so that the refrigerating apparatus and the lubricating oil composition may be used stably for a prolonged period of time. A lubricating oil composition according to the invention comprises as base oil components a polyol-ester type oil formed by reacting specific polyhydric alcohol with a fatty acid, to which tricresylphosphate and epoxy compound comprising glycidyl ether or carbodiimide are added at respective specific rates.

Abstract: A refrigerating unit having at least one refrigerating machine oil using polyol ester system oil as its base oil in at least one refrigeration cycle using at least one hydrofluorocarbon system refrigerant as a refrigerant, the present invention sets the purity of hydrofluorocarbon system refrigerant to the level higher than 99.95 wt % and the mixing of chlorine system refrigerant to the level lower than 80 ppm. In addition, the performance and reliability of refrigerating unit using the hydrofluorocarbon system refrigerant such as R134a can be enhanced by making the said polyol ester system oil to be the chemical compound of particular physical properties, by suppressing the equilibrium water content of refrigeration cycle and by limiting the residual chlorine volume.

Abstract: A lubricant for a refrigerating unit uses a hydrofluorocarbon system refrigerant with a polyol ester system oil as its base oil. The purity of hydrofluorocarbon system refrigerant is set to a level higher than 99.95 wt % and the mixing of chlorine impurity in the system refrigerant is set at a level lower than 80 ppm. The performance and reliability of a refrigerating unit using the hydrofluorocarbon system refrigerant, such as R134a, can be enhanced by making the polyol ester system oil of a chemical compound having particular physical properties, by suppressing the equilibrium water content of refrigeration cycle and by limiting the residual volume.

Abstract: 1,1,1,2-Tetrafluoroethane is used in a refrigerator as the refrigerant, while a polyolester oil which is well compatible with the refrigerant is used as the base oil and a phenolic antioxidant, a specified amine and a phosphoric triester are added thereto to give a refrigerator oil composition. Thus the hydrolysis of the polyolester oil can be prevented to thereby protect the sliding members such as a roller and a vane from the corrosion and wear which are caused by the hydrolysis.

Abstract: Disclosed is a refrigerating machine oil composition comprising:(A) 85 to 30% by weight of alkyl benzene having a kinematic viscosity at 40.degree. C. of 30 cSt or more;(B) 5 to 70% by weight of a paraffin-based mineral oil having a kinematic viscosity at 40.degree. C. of 20 to 500 cSt, a pour point of -35.degree. C. or lower, a viscosity index of 60 or more, and a sulfur content of 100 ppm or less; and(C) 1 to 30% by weight of a naphthene-based mineral oil having a kinematic viscosity at 40.degree. C. of 5 to 500 cSt, a pour point of -30.degree. C. or lower, and a sulfur content of 0.05 to 1% by weight, the total sulfur content of said composition being 0.01 to 0.10% by weight.The present composition is excellent in stability, lubricity, compatibility with refrigerants, and low temperature property.

Abstract: The present invention relates to a refrigerator oil composition which comprises 70 to 98 wt % of a paraffin base oil having a pour point of not more than -35.degree. C., a sulfur content of not more than 50 ppm (parts per million), and a kinematic viscosity at 40.degree. C. of 5 to 500 cSt (centistrokes) and 30 to 2 wt % of a naphthene base oil having a pour point of not more than -35.degree. C., a sulfur content of 0.05 to 1 wt % and a kinematic viscosity at 40.degree. C. of 5 to 500 cSt, and in which the sulfur content is 0.01 to 0.10 wt %.The refrigerator oil composition of the present invention effectively prevents the formation of valve sludge. The refrigerator oil composition of the present invention is also excellent in anti-wear properties. Furthermore the refrigerator oil composition of the present invention is excellent in stability and baking resistance in the condition that is in contact with the refrigerant (Furon) and further is excellent in low temperature solubility.