DRILL FOR MACHINING POLYMERIC COMPOSITION MATERIAL, FIBER CARBON AND FIBER GLASS Russian patent published in 1997 - IPC

FIELD: mechanical engineering. SUBSTANCE: cutting edges of the drill are curved in projection on the axial plane of the drill and are arranged on a rotation surface whose axis is coincident with the axis of the drill. The drill is provided with guide strips. The projection of the cutting edges on the plane perpendicular to the axis of the drill is a spiral. The projection of the cutting edges on the axial plane may be semi-ellipse, parabola or exponent and conjugated with the edges of the guide strips at an angle more than 0° but less or equal to 5°. EFFECT: enhanced efficiency. 5 dwg