摘要 |
<p>The present invention relates to a rock drill bit (1) for percussive drilling. The drill bit comprises a bit body (2); a head portion (3) defining a longitudinal center axis (CL). The head portion comprises a front face (24) having an outer surface portion (25), and an inner surface portion (26) disposed radially inside of the outer surface portion. The inner surface portion is partially recessed by a cavity (27) with respect to the outer surface portion (25). A plurality of fluid channels (16-18) extends through the head portion and communicates with the cavity (27) for conducting a flushing medium thereto. The inner surface portion (24) comprises a raised portion (28) carrying a plurality of buttons (13-15). An imaginary circle (C) intersects centres of the fluid channels (16-18) and also intersects an equal number of buttons (13).</p> |