Abstract: In a method for machining grooves, especially fir-tree grooves (13), which are provided for accommodating blades (19), on a rotor (10) of a turbine, especially a low-pressure steam turbine, great simplification and high flexibility is achieved by the fact that in the grooves, or fir-tree grooves (13), material is removed by a program-controlled milling device, wherein the milling device is inserted into the groove, or fir-tree groove (13), with a milling tool (20) which is guided along the places in the groove, or fir-tree groove (13), which are to be machined, by a milling tool positioning device, which is freely movable in space.

Abstract: A method for machining a gas turbine rotor which is provided with a cooling air slot which concentrically extends around the axis of the gas turbine rotor and is supplied with compressed cooling air via axial cooling air holes which at the side lead into the slot base of the cooling air slot, and the opening of which is covered by bridges which are arranged in a distributed manner over the circumference and spaced apart from each other by gaps. A crack-resistant slot shape is achieved without intervention into the configuration of the bridges by a material-removing tool, particularly a milling tool, being lowered in the gaps between the bridges one after the other into the cooling air slot and in this way the slot base of the cooling air slot being machined and widened over the entire circumference.

Abstract: In a method for machining grooves, especially fir-tree grooves (13), which are provided for accommodating blades (19), on a rotor (10) of a turbine, especially a low-pressure steam turbine, great simplification and high flexibility is achieved by the fact that in the grooves, or fir-tree grooves (13), material is removed by a program-controlled milling device, wherein the milling device is inserted into the groove, or fir-tree groove (13), with a milling tool (20) which is guided along the places in the groove, or fir-tree groove (13), which are to be machined, by a milling tool positioning device, which is freely movable in space.

Abstract: A method for machining a gas turbine rotor which is provided with a cooling air slot which concentrically extends around the axis of the gas turbine rotor and is supplied with compressed cooling air via axial cooling air holes which at the side lead into the slot base of the cooling air slot, and the opening of which is covered by bridges which are arranged in a distributed manner over the circumference and spaced apart from each other by gaps. A crack-resistant slot shape is achieved without intervention into the configuration of the bridges by a material-removing tool, particularly a milling tool, being lowered in the gaps between the bridges one after the other into the cooling air slot and in this way the slot base of the cooling air slot being machined and widened over the entire circumference.

Abstract: The invention relates to a displacement and/or positioning device for the displacement and/or positioning of an object in five axes, comprising an object support and five coupling members which support the object support in a frame, whereby four of the five coupling members are each connected to the object support by means of a first joint arrangement each with two degrees of freedom and the remaining one of the five coupling members is connected to the object support by means of a second joint arrangement with one degree of freedom.

Abstract: The invention relates to a displacement and/or positioning device for the displacement and/or positioning of an object in five axes, comprising an object support and five coupling members which support the object support in a frame, whereby four of the five coupling members are each connected to the object support by means of a first joint arrangement each with two degrees of freedom and the remaining one of the five coupling members is connected to the object support by means of a second joint arrangement with one degree of freedom.

Abstract: A method is provided for controlling the movement of a support relative to a base by movement devices whose degrees of freedom of movement define a non-orthogonal coordinate system. For achieving a dynamic behavior corresponding to that of a machine with orthogonal directions of movement, non-orthogonal actual-condition values of the movement devices are detected, transformed into orthogonal coordinates, and, on the basis of the transformed actual-condition values and the predetermined target-condition values, operating values in orthogonal coordinates are determined, which are then transformed into non-orthogonal coordinates and transmitted to the individual movement devices. In addition, a device for controlling the movement of the support is provided, as well as a machine tool with a hexapodal suspension of the support, which has provided thereon a machining device.

Abstract: A tripod bearing device featuring a stationary frame and a carrier moveable relative to it, which are connected together via three braces that are adjustable in their lengths. Each brace is coupled to the frame and to the carrier via a joint each with two rotational degrees of freedom. Moreover, a torsion drive is assigned to each brace for twisting the carrier-end joint of the relevant brace relative to the frame-end joint of this brace about its longitudinal axis. Consequently, a constructively simple parallel structure with three machining axes can be realized which, with its high dynamic stiffness, enables an accurate positioning of the carrier. Furthermore, a method for torsion compensation in the braces is given.

Abstract: In known hexapodal machining centers, a movable support is supported and the individual struts are articulated on the support in one plane. For permitting a greater movability of the support, especially in the rotational degrees of freedom, and for improving the absorption of the forces, a hexapodal machining center having a stationary frame and a movable support is provided, in the case of which the six connecting struts of adjustable length are articulated on the support. Three articulation points respectively define a common plane of application so that two separate planes are defined. Also, the articulation of the struts on the frame is effected in two separate planes of application.