DRILLING CUTTING BREAKING BIT Russian patent published in 2013 - IPC E21B10/42 

FIELD: mining.

SUBSTANCE: drilling cutting breaking bit contains casing with through axial hole, cover in closed position mated with notch at the bottom part of the hole and pivotally connected to the casing in plane of hole axis, and cutters located at external side of the cover. At the end surface of the casing there is a diametrically located groove, and on the cover - radial bosses mated to the said groove. Cover pivot connection to the casing is formed by round sockets coaxial to each other and located at opposite sides of one of radial bosses of the cover and pins mated to these sockets and congruent to them formed at the ends of structure elements fastened to the casing of the bit, for example, by welding.

EFFECT: strength of pivot connection of the bit cover to the casing at significant reduction of pivot size, like interferences deteriorating cutting properties of the bit.

7 cl, 9 dwg