Abstract: A securing device for a workpiece spindle of a lathe includes a spindle housing having a plane surface and rotatably supporting a workpiece spindle, a brake disk non-rotatably connectable with the workpiece spindle, a clamping device for fixing the brake disk and mounted on the spindle housing, the brake disk being formed as a disk which is rigid in a circumferential direction and is bending-resistant in a direction of a spindle axis, the disk being pressable by the clamping device against the plane surface of the spindle housing.

Abstract: A machine tool comprises two workpiece spindles having a spindle axis and located axially opposite to one another, at least one of the workpiece spindles being movable in an axial direction for transferring a workpiece from a clamping location to a working location, at least two tool carriages which are movable independently of one another parallel to the spindle axis and perpendicular to the spindle axis, guides arranged at opposite sides of the spindle so that tools of both the tool carriages can work both a workpiece held in one of the tool spindles and a workpiece held in the other of the tool spindles, two revolvers each arranged on a respective one of the tool carriages and provided with a plurality of tool receptacles, one of the two revolvers having a switching axis which extends perpendicular to the spindle axis, while the other of the two revolvers has a switching axis which extends parallel to the spindle axis, and the tool receptacles of the revolvers are formed so that the tools in both two revol