Manufacturing machine and manufacturing method for the production of a filter for a tubular element

A manufacturing machine (8) for production of a filter (2) for a tubular element (1) for a smoking article;

• the manufacturing machine (8) comprises:
• a folding conveyor (45), which moves a sheet (4) along a folding path (P5), said sheet (4) having an inner portion (5) and a sole outer portion (6);
• a feeding station (S8), where the folding conveyor (45) receives the sheet (4) and engages the sole outer portion (6) of the sheet (4), leaving the inner portion (5) of the sheet (4) free;
• at least one first folding station (S9), where the inner portion (5) of the sheet (4) left free by the folding conveyor (45) is folded;
• and
• an insertion station (S6), where the folding conveyor (45) releases the sheet (4) having a folded inner portion (5);
• wherein:
• the folding conveyor (45) comprises at least one first pocket (47) designed to house the sheet (4), engaging the sole outer portion (6) of the sheet (4), thus leaving the inner portion (5) of the sheet (4) free;
• and
• in the at least one first folding station (S9), the inner portion (5) of the sheet (4) left free by the at least one first pocket (47) is folded like bellows of an accordion.