| 摘要 |
<p>A chain guiding rail for use in power chain saws has a tip part defining an accurate run-in section extending from an end point of a forward-run section to the vertex of the tip part, and a run-out section extending from the vertex point to a start point of a return-run section. The run-out section has a substantially larger diameter and a tangential line at its center point forms an angle of 40.degree. to 70.degree. with a center axis of the rail. To eliminate kickbacks during operation of the chain saw the vertex is situated in a sector of the tip part which is delimited by a reference line coinciding with the center axis or extending in parallel thereto, a perpendicular line relative to the forward-run section at the end point and to the parallel reference line or the center axis, and an arc whose center of curvature coincides with the point of intersection of the parallel reference line with the perpendicular line.</p> |
