DRILL BIT Russian patent published in 1997 - IPC

FIELD: bore-hole drilling equipment. SUBSTANCE: this is used for drilling bore-hole of various application. Drill bit has central flushing unit with threaded bush having supporting shoulder on its inner surface, head-piece with sealing ring and threaded lock. Lower end of head-piece and shoulder are in the form of taper with its top facing towards cutting face. Tapered end of head-piece has slot for sealing ring. Slot is formed by second tapered surface located step-like relative to first tapered surface and tapered surface of step. Slot cross-section is rhombic, and sealing ring is located on its large diagonal. This configuration of drill bit improves its operating efficiency and at same time simplifies its design and manufacturing. EFFECT: high efficiency. 2 cl, 3 dwg