Patent attributes
A design for a rotary drive both for a tool and for a workpiece to be rotationally driven is proposed. This rotary drive design contains a cylindrical basic shape which deviates from a circular cylindrical shape. The contour or the cross section through this basic shape has a plurality of rounded projections and rounded recesses arranged between said projections. The projections tangentially touch a circle having a maximum radius, while the recesses, for their part, tangentially touch a circle having a minimum radius. Deviating from this cylindrical basic shape, in the regions between the projections are configured conical surfaces, which are not instrumental in the transmission of torques, but take care of centering and alignment between the tool and the workpiece.