DRILL HEAD FOR DRILLING HOLES IN HARD MATERIAL Russian patent published in 1998 - IPC

FIELD: drilling equipment. SUBSTANCE: drill head is intended for drilling holes in rock and other hard materials. It has body acting as central support, spindle directed upwards secured in top of body and having vertical axle, fixing head at top for its splittable connection with drill barrel which in process of operation rotates drill head around vertical axle of spindle and advances it in hard material subjected to drilling. Drill head is provided with at least two striking hammers located on body so that in process of operation hard material is split along at least one round path passing across center of vertical axle. Each striking hammer has pneumatically operated striking tool seated in body spaces, and drill bit brought in operation by striking tool. Central spaces have longitudinal holes made in integral part and located in parallel to vertical spindle axle at short distance from this axle. Drill bit of each striking hammer is attached to upper member screwed on to top of corresponding hole so that it can freely rotate. It is provided with torsion spring to prevent spontaneous unscrewing from aforesaid hole. EFFECT: high efficiency. 7 cl, 2 dwg