| 摘要 |
PROBLEM TO BE SOLVED: To provide a highly-efficient and highly-reliable hermetic type compressor that, in rolling of a ball of a thrust ball bearing, suppresses the generation of wear of raceways on rolling surfaces of an upper race and a lower race where the ball rolls and that prevents an increase in input.SOLUTION: A plurality of balls 168 are arranged in a holder 170 so that a distance of radius of gyration of the balls 168 is not same as the center of gyration of a shaft 140. A gap is provided between an inner diameter part 176 of the holder 170 and an outer periphery 178 of a main shaft 142. Rolling on the same raceway of each of the balls 168 is greatly reduced, whereby the efficiency is improved by an input reduction and the reliability is also improved by prevention of sliding wear. |
