US Patent 9643264 Coupling mechanism for cutting tool

A rotary cutting tool includes a cutter of generally cylindrical shape disposed about a central longitudinal axis. The cutter has a first end having an active fluted portion and an opposite second end, the second end having a male threaded portion disposed thereabout. The cutting tool further includes a shank of generally cylindrical shape disposed about the central longitudinal axis, the shank having a recessed female threaded portion formed in a first end. The male threaded portion includes a number of threads disposed at a first pitch and the female threaded portion includes a number of threads disposed at a second pitch different than the first pitch. The cutter and the shank are selectively coupled via threaded engagement of the male threaded portion and the female threaded portion.