| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a ball screw capable of suppressing the occurrence of impression and the deterioration in lubrication performance due to wear powder. <P>SOLUTION: An arithmetic average roughness of a through path 19 for returning balls formed in a nut 12 by drilling or the like is made to be 10μm or less, preferably 5μm or less. <P>COPYRIGHT: (C)2004,JPO&NCIPI</p> |
