Patent ID: 9211607
Filing Date: 2015-12-15
Classification: B23K

Abstract:
1. A device for simultaneously processing a circumference of a workpiece with laser beams, the device comprising: a plurality of laser-lens modules, each including a diode laser having a fast axis and a slow axis and a beam-forming lens system disposed in front of the respective diode laser, the laser-lens modules being disposed at equal distances from each other on a circle, the laser-lens modules each being configured to emit a laser beam radially in a shared radiation plane with respect to a mid-point of the circle such that axes of the laser beams intersect in the midpoint; and a waveguide haying a shape of a straight cylinder with a cylinder axis, the waveguide being disposed within the circle with the cylinder axis being perpendicular to the radiation plane and extending through the mid-point of the circle and a recess being formed around the cylinder axis, the recess being configured to hold a workpiece during the processing, the waveguide including a lower part and an upper part together forming a cavity enclosing the radiation plane, the cavity being open due to the recess, the cavity having a bottom surface configured to reflect the laser beams and a cover surface configured to reflect the laser beams, the cavity having a beam inlet opening toward each of the plurality of laser-lens modules along a circumference of the waveguide; wherein the laser-lens modules are each configured to emit the laser beam so as to be reflected repeatedly between the bottom surface and the cover surface of the waveguide in the direction of the fast axis, wherein the beam-forming lens system is configured in such a way that it widens the laser beam in the direction of the fast axis to such an extent that it already strikes the bottom surface and the cover surface shortly after entering the waveguide, and to propagate in an unaffected manner within the radiation plane in the direction of the slow axis so as to form a beam spot that strikes the workpiece with a homogenous energy distribution due to the repeated reflections in the direction of the fast axis, the beam spot having a height in a direction of the cylinder axis based on a distance between the bottom surface and the cover surface and a width based on a divergence angle of the laser beam in the radiation plane and a distance of the laser-lens module from a surface of the workpiece.