| 摘要 |
PROBLEM TO BE SOLVED: To provide a lightweight guide rail capable of achieving high positioning accuracy and high strength, etc. SOLUTION: The guide rail 5 is a long and nearly square rod member composed of a silicon nitride sintered body. The guide rail 5 is provided with a small diameter side surface (surface A) of a throughhole 19, a large diameter side surface (surface B) opposing the surface A, a surface C and a surface D of the right and left sides contiguous to the surface A and the surface B. A step recessed part 15 is provided on the surface B side of the central part located at nearly a center in the horizontal direction of the guide rail 5. At the end parts in the longitudinal direction of the bottom 16 of the step recessed part 15, i.e., at the ends in the horizontal direction of the figure, R-chamfers 18 are formed along the direction perpendicular to the plane of the sheet. These R-chamfers are formed by R-chamfering work to make inwardly convexed corners. COPYRIGHT: (C)2003,JPO |
