Drill bit i.e. three-lipped core drill bit, for drilling steel reinforced concrete, has main blade extending between drill bit part and auxiliary bit part and formed as single piece with bit head, where main blade is attached to wing blades

摘要

The drill bit (10) has a drill bit head (12) made of hard metal, where the drill bit head has a set of wings (18, 22) at which radially extending wing blades (32) are formed. A central main blade (28) is attached to each wing blade and arranged opposite to the wing blades at an angle, where the main blade extends between a drill bit part (26) and an auxiliary bit part (30) and formed as a single piece with the drill bit head. The main blade extends radially outward starting from the wing blades for forming a concave groove.