DEVICE FOR HOLE DRILLING Russian patent published in 1996 - IPC

FIELD: mining and construction. SUBSTANCE: device for hole drilling includes body, driving rod and side spindles with drill bits installed in body. To increase efficiency of drilling with simultaneous reduction of power consumption, side spindles are made hollow, and driving rod is made in form of double drill pipe whose external column is rigidly attached to body and internal column is installed for rotation by individual drive and kinematically connected by means of gear wheels with side spindles whose hollows are communicated with interpipe space of driving rod. Device is furnished with central hollow spindle installed on lower end of internal column and fixed to prevent turning, and packer located in lower part of body. Packer is made in form of body installed for axial motion relative to device body. Annular flexible collar is located for rotation on packer body. Ring with external cone-cylindrical surface is installed on device body for rotation and its location during axial motion between device body and collar. EFFECT: higher efficiency. 3 cl, 5 dwg