Tapping attachment for a machine tool

摘要

A tapping attachment for a machine having at least one rotating workpiece spindle and associated coaxial tool drive shaft. The tapping attachment couples a tapping tool to the drive shaft in a manner selectively controlling the tool to rotate with respect to a workpiece attached at one of two predetermined velocities in the same direction as the spindle. The attachment is selectively adapted so that one of the two velocities is above and the other below that of the spindle.