| 摘要 |
<P>PROBLEM TO BE SOLVED: To make an inverter compressor rotating at a frequency exceeding a frequency of an electric power source low in noise, highly efficient and highly reliable by reducing slip of balls and preventing wear even in high speed rotation. <P>SOLUTION: A relation expression Fa>2.0×10<SP>-3</SP>×m×Z×d×n is satisfied, where weight per one ball 135 is represented by m[g], the number of the balls 135 by Z[units], a raceway diameter of the balls 135 by d[mm], the maximum rotation speed of a shaft 110 by n[r/s], and load in the gravity direction acting on a thrust ball bearing 140 by Fa[N]. Since the balls 135 do not easily slip and rotate stably by keeping load acting on the balls 135 in high speed rotation at a fixed value or higher, wear of the balls 135, an upper washer 138 and a lower washer 139 can be reduced. <P>COPYRIGHT: (C)2008,JPO&INPIT |
