| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a ball spring that prevents increase in internal pressure and prevents a foreign matter from entering from the outside to the inside and excessive leakage of a lubricant. <P>SOLUTION: A sealing device 14 of a ball spring 1 has two substantially annular elastic members 21. The elastic members 21 and 21 are fixed to a nut 12 across an axial gap 22. The sealing device 14 includes a discharging hole 20 for connecting the inside and the outside of a gap 17 to discharge the air in the gap 17 to the outside. The discharge hole 20 includes three holes connected in series. Holes 23 and 23 at both ends among the three holes are formed on the elastic members 21 and 21. In addition, the center hole among the three holes is the axial gap 22 formed between the two elastic members 21 and 21. A cross section of the axial gap 22 is larger than that of the holes 23 and 23, and is the largest among the three holes. The discharge hole 20 constitutes a labyrinth structure in the discharge hole 20. <P>COPYRIGHT: (C)2013,JPO&INPIT |
