Abstract: Variation in hole diameter due to heating effects is minimized even if the shortest machining route is set, and machining quality is improved. A printed circuit board to be scanned by a laser beam is divided into a plurality of scan areas (S1). An order of drilling within the scan area is sorted to obtain a scanning route with the shortest distance (S2). The order of the (N+1)th hole and the (N+2)th hole is swapped in each scanning area if it is determined that the distance between the Nth hole and the (N+1)th hole (here, N is an integer in a range of 1?N?“the maximum number of holes to be drilled in the area”?1?) is less than a predetermined threshold value, and that N+1 is not correspond to the maximum number of holes to be drilled in the scanning area (S3).

Abstract: The soldering arrangement has a lengthwise extending tunnel arrangement (1) with a soldering tunnel (3) through which a conveyor arrangement (10) for the work pieces extends. A soldering tunnel (3) which is inclined upwardly in the conveying direction is provided with a floor opening which is surrounded by a downwardly protruding sealing skirt (18) which is immersed in the molten liquid solder material (20) in a tub (19) below the soldering tunnel (3). The soldering nozzles (24, 25) arranged within the soldering tunnel (3) are supplied through riser channels within the sealing skirt (18). A protective gas conduit (41) for supplying nitrogen opens into the soldering tunnel (3). The soldering tunnel (3) and the conveyor path of the conveyor arrangement (10) extending within the soldering tunnel (3), are tiltable about a horizontal crosswise axis (47), whereby the inclination of the soldering tunnel (3) is adjustable.