Fecha de publicación: -- Fuente: WIPO "tomato" There is described a packaging machine (1) for producing packages (2) starting from a web (4) of packaging material and comprising: a plurality of folding rollers (6) configured to interact with the web (4) to fold the web (4) into a tube (3); a heating device (13) for heating the packaging material at a heating station (H); a presser roller (14) designed to be located inside the tube (3) arranged downstream of the heating station (H) and configured to press the heated packaging material against the folding roller (6); the heating device (13) and the folding roller (6) are configured to be moved selectively in: a first position, in which the heating device (13) faces, a first section (52) of the tube (3) at the heating station (H) and upstream of the presser roller (14), and in which the folding roller (6) cooperates in abutment with the presser roller (14); a second position, in which the folding roller (6) is spaced from the presser roller (14) and in which the heating device (13) faces a second section (53) of the tube (3) arranged downstream of the heating station (H); a third position, in which the folding roller (6) is spaced from the presser roller (14) for allowing a distancing of the packaging material away from the presser roller (14), and in which the heating device (13) is inoperative.