HOLLOW DRILLING BIT Russian patent published in 2012 - IPC B23B51/04 

FIELD: machine building.

SUBSTANCE: drilling bit contains cutting plates attached to peripheral edge of opening of section of cylindrical housing end, the plates being spaced-apart and protruding radially from inner and outer peripheral surfaces of housing. Housing has a shallow thickness of wall and outer peripheral surface of section of housing end has a narrowing surface, at that outer peripheral surface is closer to inner peripheral surface in direction to the end. Recesses for cutting plates are made on peripheral edge of opening of section of housing end. Recesses are opened to the end and spread to the bottom. Housing section adjacent to the front section of each recess in rotation direction is bent inside radially. Constructional realisation of cutting plates and their attachment to housing of drilling bit is presented.

EFFECT: effective drilling of holes under low torque moment of wireless hand drill.

5 cl, 6 dwg