Positioning device having static fluid bearings

摘要

A positioning device comprising a PSI -carriage (85) which is guided along a circular cylindrical guide (79) of a transverse carriage (65) by means of a static fluid bearing (87) and which can thus rotate about an axis of rotation which coincides with a centreline (83) of the circular cylindrical guide (79). A working point (107) of a tool (93) fastened to the PSI -carriage (85) is lying on the axis of rotation (83) so that an angular adjustment of the tool (93) effected by rotation of the PSI -carriage (85) can take place independently of a position adjustment of the working point (107) effected by a displacement of the transverse carriage (65) and a longitudinal carriage (7). The positioning device can be used in machined for the processing of surfaces, in particular in the manufacture of linear and circular Fresnel lenses for projection television screens by means of a cutting tool.