US Patent 7131799 Cutting insert with helical geometry and holder therefor

A cutting tool insert and holder therefore, the drill insert having a helical geometry corresponding to helical flutes in a drill body holder which enable the drill tool assembly to more efficiently remove chips from a hole during operation, the drill insert comprising a drill insert body having a first end opposite a second end, a plurality of helical flutes formed in the drill insert body, a plurality of cutting edges formed at the interfaces of the plurality of helical flutes and the first end of the drill insert body, and an aperture formed in each helical flute.