Sanyo Electric Co., Ltd.

Kiyoshi Tanaka

Yutaka Hirano

Takashi Sunaga

Yasuki Takahashi

Masato Watanabe

Hirokazu Kawakami

Ryuji Watanabe

Seiki Jikuhara

Kiyoshi Akazawa

Takeo Komatubara

Hiroshi Takagi

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.

Refrigerating unit

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.

A hermetically sealed electric motor compressor, comprising a hermetically sealed casing, a reciprocating compressor unit mounted within the casing and compressing a working fluid, the compressor unit having a first discharge passageway, a valve assembly mounted within the casing and opening and closing the first discharge passageway, the valve assembly having a second discharge passageway, a discharge port mounted to the second discharge passageway within the casing and including a muffler. The muffler defines a plurality of resonance chambers. The discharge port includes a base plate having a projection. The valve assembly includes a reed valve assembly including a reed valve and a valve backer mounted behind the reed valve. The valve assembly includes a valve seat defining a recess receiving the reed valve assembly, and an elastic gasket and a holder elastically holding an end of the reed valve assembly within the recess so that the projection of the base plate pushes the end of the reed valve assembly on the bottom of the recess by means of the gasket. The valve backer limits the degree of opening of the reed valve and accelerates the return speed of the reed valve.

Hermetically sealed electric motor compressor

A piston assembly for compressors wherein a piston is connected to a crankshaft by a connecting rod having a ball at its one end, the ball being, with the rear portion thereof, joined to the piston by clamping a clamp portion provided on the piston, while the front portion of the ball is in contact with a ball seat formed in the inner portion of the piston, the crankshaft being formed at its upper end with an oil outlet for scattering an oil upon ejection therefrom, the piston assembly being characterized in that a plurality of holes are formed in the clamp portion, the piston having a skirt portion formed with a plurality of holes opposed to the respective holes.

Growing community of inventors

Ohra-gun, Japan

Kiyoshi Tanaka