Drilling head for rock drilling

摘要

In a drilling head for rock drilling in which the roller bits (24A, 24B, 24C) arranged at irregular peripheral distances apart lie with their generating lines (114, 118) which face the bottom (20) of the drilled hole against an approximately conical annular surface which is common to them and is formed in such a way as to be set back from outside to inside, in order to increase the drilling capacity the roller bits (24A, 24B, 24C) have a basic shape which respectively comprises two frustoconical circumferential sections (100, 102) which adjoin one another with their ends (104, 106) of smaller diameter. <IMAGE>