| 摘要 |
The invention is concerned with a shank adaptor for a rock-drilling machine provided with at least one side flushing hole which connects an axial flushing hole of the adaptor with the outside thereof and which, together with the axial flushing hole, serves as a passage for transporting flushing medium. The side flushing hole has an oblong cross-sectional shape with the longitudinal axis of the oblong parallel to the longitudinal axis of the shank. The shank adaptor of the invention enables stress concentration at the outer edge of the side flushing hole to be reduced while decreasing hole-edges sensitive to fractural impressions by half, which also results in a reduction in the probability of fatigue cracks caused thereat by the rotary bending forces on the adaptor. |
