| 摘要 |
The invention relates to a drill bit (20) for percussive rock drilling, which comprises:
- a drill head (21);
- a skirt (24), which has a first end and an opposite second end, the skirt being connected to the drill head at said first end;
- a recess (25) extending axially through the skirt from the second end of the skirt towards the first end thereof, the recess being provided with an internal, cylindrical female rope thread (26); and
- an impact surface (27) at the bottom of the recess.
Every cross-section of the recess (25) between the impact surface and the part of the recess where the female rope thread has its full thread profile has a cross-sectional area which is equal to or smaller than the cross-sectional area of a cross-section of the recess at the part of the recess where the female rope thread has its full thread profile. |
