LABELLING MACHINE WITH ULTRASOUND WELDING DEVICE FOR MAKING A TUBULAR LABEL MADE OF HEAT-SHRINKING FILM AND WELDING PROCESS

摘要

The invention refers to the field of labelling machines that use tubular labels, and in particular it refers to ultrasound welding apparata for making a tubular label made of a heat­shrinking film, precut from a coil. The apparatus provides for the label welding for the whole length of the surmount (5), the apparatus being able to translate on at least two Cartesian axes; moreover, it guarantees one or more welding beads due to the presence, on the sonotrode, of a plurality of ribs (6): the formation of one or more beads will have to be attributed to the more or less correct position of the precut label and the errors caused during its transfer. The presence of many beads is an improving condition of the resistance to tensile stress of the welded label.