Absauganlage

The invention relates to an extraction system for the removal of reaction products which are produced during the processing of materials by means of a laser. A gas-tight fume hood is affixed slightly above the workpiece on the laser focusing unit and a partial vacuum is produced under the fume hood by means of a pump. Closely arranged nozzles facing inwards at an angle are mounted on the edge of the fume hood. A gas flows through these nozzles to the workpiece, thus forming a closed gas curtain which, on account of the slanting position of the nozzles, produces no accumulation zones at the point of impact. Said gas flows centrally, as a result of the interaction with the partial vacuum, to the processing area and from there upwards and away. The extraction power is designed so that a partial vacuum is maintained underneath the fume hood despite the gas entering via the nozzles and any additional laser reaction gases fed in via the laser focusing unit. As a result of this method, all su bstances, reaction products and supplied gases occurring in the reaction area are detected completely and removed.