Patent DE-102011116833-A1 (DE)
Title: Laser machine for processing a workpiece, comprises a laser source for processing a workpiece and for adjusting beam on the workpiece, and a unit for rotating the laser beam around the beam axis
Inventor: LUEDI ANDREAS
IPC: B23K26/06
Filed: 2011-10-25
Abstract: The laser processing machine (1a) comprises a laser source (2) for processing a workpiece (7) and for adjusting beam on the workpiece and a unit for rotating the laser beam around the beam axis. The rotating unit is formed by a drive in such a manner that the emitted laser beam is rotated around the beam axis and is formed by a rotatable, motor propelled optic element (3), which is intended to displace the part of the laser beam lying in the optical path behind the optic element in rotation so that the partial beam is rotated around the beam axis. The laser processing machine (1a) comprises a laser source (2) for processing a workpiece (7) and for adjusting beam on the workpiece and a unit for rotating the laser beam around the beam axis. The rotating unit is formed by a drive in such a manner that the emitted laser beam is rotated around the beam axis and is formed by a rotatable, motor propelled optic element (3), which is intended to displace the part of the laser beam lying in the optical path behind the optic element in rotation so that the partial beam is rotated around the beam axis. The optic element is implemented as light conductor, where one end arranged adjacent to the laser source is fixed and the other end is motor driven, and as dove prism. The optic element is formed from a combination of a first mirror, a second mirror and a third mirror, which are arranged in such a manner that the laser beam is radially guided away from the original axis of the laser beam by the first mirror, is guided radially to the axis by the second mirror and is guided into original axis of the laser beam by the third mirror, where one of the mirrors is motor driven. The laser source is arranged directly over a processing head (4) movable opposite to the workpiece. A controller is intended to align the major axis of an asymmetric beam profile of the laser beam and a polarization direction of the laser beam along a processing direction of the laser processing machine. A unit for changing the polarization of the laser source is provided. The major axis of an asymmetric beam profile of the laser beam and the polarization direction of the laser beam are equally orientated. The beam parameter product in a polarization direction aligned along the section gap is larger than perpendicular to it. A unit for the reduction of the polarization of the laser beam is provided on two directions standing crosswise to one another in beam direction. A polarizing beam splitter element is intended for partitioning the laser beam into a p-linear polarizing partial beam toward the original laser beam and s-linear polarizing partial beam parallel to the dispersed partial beam. Laser sources are arranged for creating partial beams, which are polarized in two directions standing crosswise to one another in beam direction. A beam recombination element is arranged for the recombination of the two partial beams according to redirection of one of the two partial beams in a common axis. An element for attenuation of one of the two partial beams is arranged. The polarization direction of the laser beam, which is aligned always along a processing direction of the laser processing machine, is the direction of the p-polarization. The p-linear polarizing partial beam is guided to a first machining head and the s-linear polarizing partial beam is guided to a second machining head. The machining heads are independently movable. An independent claim is included for a method for processing a workpiece.