be turnable about its axis 7 in the journal body 2 is a workpiece spindle shaft 6 which is spaced by the distance x from the axis of the torsion shaft 3 the axis 7 of the spindle shaft 6 extends parallel to the axis 9 of a grinding disk 10 which is used for grinding a workpiece mounted on the spindle shaft 6 particularly a tap type drill for this purpose centers 11 or clamping jaws 12 can be used which are connectable to the free end of the workpiece spindle shaft 6 mounted on the torsion shaft 3 is a drive gear 13 which can be driven by a not illustrated motor and which meshes with an output drive gear 14 and is mounted on the axis 7 of the spindle shaft 6 this effects rotation of the spindle shaft 6 independently of any possible floating movement of the journal body 2 together with the spindle shaft 6 about the pivot axis 8 of the journal body 2 a lever 16 is mounted on the journal body 2 at the pivot 15 and the longitudinal axis 17 which essentially extends normal to the connecting line between the axis 3 of the body 2 and the spindle shaft axis 7 the lever 16 carries on its underside a cam follower roller 18 which is in engagement with the cam arrangement 4 5 and at its.