Patent ID: 7325633

Claim:
A drill bit for percussive rock drilling including an integral skirt defining an axial center line, the bit including an axial front face having rock crushing elements, at least one channel for conducting a flush medium, a recess extending forwardly by an axial distance L 0 from a rear end face of the skirt, a female thread formed in the recess, and an external surface comprising a conical portion which extends rearwardly from a larger diameter end thereof to a smaller diameter end thereof, wherein the larger diameter end is spaced from the rear end face by an axial distance which is greater than ⅛ of the distance L 0 and less than the distance L 0 , and wherein an imaginary apex of the conical portion lies on the center line at a distance rearwardly from the rear end face, which distance is greater than ¼ of L 0 .