Device in a tool holding assembly for moving a rotatable shaft in the axial direction

A device in a tool holding assembly for axially moving a rotatable shaft on which is arranged at a first end of the shaft a device for performing work during rotation of the shaft, comprising a driving device for effecting rotation of the shaft, and at least one bearing radially supporting the shaft and permitting movement of the shaft in the axial direction, the shaft having a free second end, electromagnetic means arranged relative to the shaft for drawing the shaft in the axial direction from the first end toward the second end in opposition to pressure acting against the second end in an opposite axial direction, and control means for controlling the electromagnetic means to achieve the axial movement of the shaft during rotation of the shaft, said electromagnetic means comprising a stationary journal having a free end positioned axially adjacent the second end of the shaft and a magnetic coil arranged around an exterior of the journal for generating a magnetic field.