ROTARY DRILLING BIT (VERSIONS) Russian patent published in 2013 - IPC E21B10/22 

FIELD: mining.

SUBSTANCE: rotary drilling bit comprises legs with inclined journals and mills installed on them with radial channels, in which lock and stop pins are arranged, being matched with circular grooves of journals. According to the first version, each stop pin is made of an easily deformable material, such as several split elements with collars on the outer surface and a conical axial channel, and the radial channel in the mill - with a circular bore under collars of the stop pin, besides, the end part of the lock pin installed in the axial channel of the stop pin has a congruous conical shape. According to the second version, each stop pin is made in the form of a collet sleeve, and radial channels in the mill - with a circular bore for the collet sleeve, at the same time collet sleeves are made with conical axial channels, and external ends of lock pins - with response conical ledges.

EFFECT: increased service life of a bit, reliable fixation of mills.

3 cl, 3 dwg