| 摘要 |
<p>The invention relates to a laser processing head (10) for processing a workpiece (10) by means of laser beam (12), comprising a housing (14), through which a beam path for the laser beam is led and which has a focusing optical unit (18) for focusing the laser beam onto a joint (42) of the workpiece to be processed, a light cutting device (30) fitted to the housing (14) and having a light source (34) for generating a light line (38) on the workpiece (16), which cuts a location to be joined at a predetermined distance (d) from the joint, a camera (24) with an optical bandpass filter (28) arranged in an observation beam path in front of the camera, wherein the light source (34) has an at least local emission maximum in the wavelength passband of the bandpass filter and the optical bandpass filter (28) is configured in such a way that the laser beam (12) is not transmitted, and wherein the camera images the light line at the location to be joined and also the portion—transmitted by the bandpass filter—of the process light of a welding bath (46) produced by the laser beam impinging on the workpiece to be processed at the joint (42) at regular time intervals, and a processing unit (40) with a memory (58) for receiving the recorded image data from the camera, which is designed to determine, by image processing of the received image data, the intersection point (50) of the light line (38) with the location (48) to be joined and also the midpoint of the welding bath (46) at the joint (42) to store the intersection points (50) between light line (38) and location (48) to be joined as a target trajectory (60) in the memory (58), and to determine a minimum distance between the stored target trajectory (60) and the current welding path midpoint.</p> |
