DRILLING ASSEMBLY Russian patent published in 2010 - IPC E21B4/02 

FIELD: mining.

SUBSTANCE: drilling assembly includes housing rigidly attached to the rotary shaft and having high pressure chamber and channels in which there arranged are air hammers, each of which has a cylinder in the central hole of which a valve with longitudinal through holes and a stem is located, a hammer head and a drilling bit, which are installed with possibility of axial movement and made in the form of a piston with a stock and central blind holes, equipped with a casing pipe the outer diametre of which corresponds to or is less than diametre of protruding part of drilling bits, and inner one is equipped with a section with small inclination angle of thread and a stop at the outlet thereof, flanged bushing with a stepped internal hole and with mating external thread on the flange relative to threaded section of casing pipe, and in the above flange there drilled are vertical through holes, turbine placed in larger diametre of inner stepped hole of flanged bushing, which has the shape of a thin-wall shell, and installed with possibility of being rotated in the direction coinciding with direction of casing pipe thread, flexible hose put on the neck of thin-wall shell, and in the end part of rotary shaft there is a cross hole interconnecting HP chamber to channels of air hammers.

EFFECT: increasing intensity of breaking process of hard rocks.

2 cl, 3 dwg