Abstract: The machine tool is provided for working ring-shaped workpieces (1), in particular one-piece turbine wheels, so-called “bladed rings”. It has a rotatable chucking device (2) for a workpiece (1). Said chucking device is mounted on a carrying part (4), which in turn is supported by a supporting component (5). In order to keep the dimension (14) of the length by which the carrying part (4) projects beyond the workpiece (1) on the side facing the supporting component (5), as low as possible, the carrying part (4) protrudes into the chucking device (2) to such an extent that it projects at least through the boundary surface (7) of the workpiece (1) facing the supporting component (5). A saving of space is achieved in this way and, therefore, enhanced accessibility is obtained for the tool to the side of the workpiece (1) facing the supporting component (5).

Abstract: Conventional positioning devices in which a body is displaceable in a plane and rotatable by three drives have the drawback that at least one of the drives is displaced together with the body, whereby these apparatus are relatively heavy and sluggish. In the case of the positioning device according to the invention, three straight guide elements, arranged radially, are rigidly connected to the body. Each guide element is accepted in a linear bearing in a longitudinally displaceable way, and each linear bearing is disposed on a separate rotor in a way pivotable about a pivot axis directed perpendicular to the plane. Through independent displacement of the linear bearings on a common circular path, the body can be shifted and rotated as desired in a region. This construction has the advantage that it is built simply and that it is able to execute quick and precise positioning movements in particular owing to small masses in motion.

Abstract: Conventional positioning devices in which a body is displaceable in a plane and rotatable by means of three drives have the drawback that at least one of the drives is displaced together with the body, whereby these apparatus are relatively heavy and sluggish. In the case of the positioning device according to the invention, three straight guide elements, arranged radially, are rigidly connected to the body. Each guide element is accepted in a linear bearing in a longitudinally displaceable way, and each linear bearing is disposed on a separate rotor in a way pivotable about a pivot axis directed perpendicular to the plane. Through independent displacement of the linear bearings on a common circular path, the body can be shifted and rotated as desired in a region. This construction has the advantage that it is built simply and that it is able to execute quick and precise positioning movements in particular owing to small masses in motion.

Abstract: The machining center serves for grinding workpieces with complex shaped surfaces, such as turbines or jet engine blades. One or several workpieces are clamped in a workpiece chucking device. The latter is displaceable along an X and a Y axis. Additionally, each workpiece is clamped rotatably around its longitudinal axis. A support device is disposed on a stand, and is displaceable along a vertical Z axial direction. One or several automatically exchangeable grinding attachments are inserted in support device. Each grinding attachment comprises grinding means driveable from support device. The support device is inclinable around an axis of inclination, which runs parallel to the Y axis. Each grinding attachment is rotatable by any angle around a grinding attachment longitudinal axis, which runs parallel to the Z axis when the support device is in the uninclined state. All said axes are numerically controlled.