Hermetic reciprocating compressor with thrust ball bearing

Abstract

A hermetic compressor includes a hermetic container that stores lubricating oil, an electrically-driven element having a stator and a rotor, a shaft having a compressing element driven by the electrically-driven element, and including an eccentric shaft portion, a cylinder block, a piston, a coupling device that connects the piston and the eccentric shaft portion, a main bearing, and a thrust ball bearing that supports a vertical load by the self weight of the rotor and the shaft. The thrust ball bearing includes a plurality of balls having a diameter of 3 mm or less, a holder portion holding the balls and formed of a polymeric material, and an upper washer and a lower washer disposed above and below the balls, respectively, and the viscosity grade of the lubricating oil is from ISO VG3 to ISO VG10.

Description

TECHNICAL FIELD[0001]The present invention relates to a hermetic compressor used for a refrigerating cycle of a freezing refrigerator, etc.BACKGROUND ART[0002]In recent years, as for a hermetic compressor used for a freezer of a freezing refrigerator, etc., attainment of high efficiency for reduction of power consumption is advanced. Conventionally, as a means for attaining the high efficiency of the hermetic compressor, a thrust ball bearing in which the sliding loss of a thrust bearing portion is reduced compared with a sliding bearing has been adopted. Meanwhile, lowering of viscosity of lubricating oil is advanced in order to reduce the sliding loss.[0003]As this type of conventional hermetic compressor, there is one in which upper and lower portions of a ball is sandwiched by a washer, and a thrust ball bearing of an inexpensive and simple configuration using a cage made of a polymeric material is used to attain high efficiency (for example, refer to Patent Document 1).[0004]He...

AI Technical Summary

Benefits of technology

"The present invention provides a hermetic compressor with a high efficiency and reliability. It includes a hermetic container for lubricating oil, an electrically-driven element, a shaft with a compressing element, a cylinder block with a compression chamber, a piston, a coupling device, a main bearing, and a thrust ball bearing. The thrust ball bearing includes a plurality of balls, a holder portion, and upper and lower washers. The use of light balls reduces the centrifugal force and surface pressure on the holder portion, preventing wear and maintaining efficiency. The compressor is suitable for high-efficiency and low-viscosity lubricating oil."

Problems solved by technology

However, in the conventional configuration, there is a problem that cage 31 may worn out and reliability may be lowered, in a case where lubricating oil 6 of low viscosity grade like ISO VG3 to ISO VG10 is used.

Images