Apparatus for Joining Two Workpiece Parts Having Regions With Different Characteristics by Means of Through-Transmission Welding

An apparatus for connecting two workpiece parts to form a workpiece by through-transmission welding by means of weld seams running in a preselected weld seam pattern in regions of the workpiece parts having different characteristics, including a receptacle configured such that two workpiece parts extending in an X direction and a Y direction are positioned relative to one another in the X direction, Y direction and Z direction of a Cartesian coordinate system, comprising a laser beam source aligned in the direction of radiation of said laser beam on the receptacle and, therefore, on workpiece parts positioned therein;

• said laser beam source having a plurality of individually controllable laser beam emitters which are arranged adjacently in the X direction;
• a transporting device for transporting the laser beam source relative to the receptacle in the Y direction, a storage-and-control unit;
• a homogenizer arranged downstream of the laser beam source in the direction of radiation;
• at least two reflection channels provided in said homogenizer which run parallel to one another in the Y direction, completely penetrate the homogenizer in the Z direction with a channel depth and are dimensioned and arranged relative to one another corresponding to a preselected weld seam pattern, one of said laser beam emitters being of different laser power associated respectively with the at least two reflection channels, said reflection channels having opposed reflecting channel wall surfaces at which at least a portion of laser radiation coming from the associated laser beam emitter is repeatedly reflected back and forth, said laser beam emitters of different laser power include at least laser beam emitters of a comparatively lower laser power and laser beam emitters of a comparatively higher power so that, with laser radiation emitting over the same duration, parallel weld seams of like quality can be generated simultaneously in regions of the workpiece parts having different characteristics.