CONE DRILL BIT Russian patent published in 1995 - IPC

FIELD: mining industry. SUBSTANCE: cone drill has fastening member of valve attachment unit. Fastening member may be made in form of clamp or pins. Clamp is installed in radial holes of heads. Pins are attached to stop shoes and pins are located parallel to drill bit axis. Valve attachment unit is made in form of two anchoring rods. Rods are installed inside nipple square to drill bit axis in diametrically opposite direction. Rod ends facing nipple has stop shoes. Rods may be installed under locking member. Rod ends may have cylindrical heads with radial holes on side surface. Rod ends may have threads with opposite cutting direction and connected to each other by means of threaded sleeve with radial holes in middle part. Made in supporting annular shoulders of seat are through holes which run through free threaded ends of pins. Screwed on pin ends are nuts. Shoes may have frictional material. Nipple inner surface in place of contact with shoes may have annular recess. EFFECT: higher efficiency. 5 cl, 5 dwg