Method and machine for simultaneously producing a number of cigarette rods

A method of simultaneously producing a number of cigarette rods (2), the method comprising the steps of feeding at least two strips (5) of paper, by means of respective conveyor belts (11), along a given path (P) extending in a given traveling direction (17) through a loading station (18), each conveyor belt (11) coming into contact with an outer surface (15) of the relative strip (5);

• transferring a respective continuous layer (20) of tobacco (7) on to an inner surface (19) of each said strip (5) at the loading station (18);
• feeding the strips (5) and respective layers (20), by means of said conveyor belts (11), along a forming beam (26);
• gradually deforming the conveyor belts (11) transversely, by means of the forming beam (26), to gradually wind the respective strips (5) about the respective layers (20) and so form respective tubular wrappings (38) presenting respective longitudinal lateral appendixes (39) projecting outwards and presenting respective longitudinal lateral inner surface portions (40);
• gumming, on each strip (5), the relative said lateral inner surface portion (40) by means of a gumming device (41);
• and turning said appendixes (39) over on to the respective tubular wrappings (38) to form respective continuous cigarette rods (2);
• characterized in that said lateral inner surface portions (40) are gummed at an intermediate point (35) of the forming beam (26) by means of said gumming device (41);
• the gumming device (41) comprising, for each said conveyor belt (11), a gumming disk (43, 44) which is rotated about an axis (46) with a lateral surface (47, 48) tangent to said lateral inner surface portion (40) of the respective said appendix (39);
• the gumming disks (43, 44) being both located over said forming beam (26);
• and said axis (46) extending over the forming beam (26) and crosswise to said traveling direction (17).

A machine (1) for simultaneously producing a number of cigarette rods (2), the machine (1) comprising a forming beam (26) for forming at least two cigarette rods (2);

• a conveyor belt (11) for each said cigarette rod (2), the conveyor belt (11) being brought into contact with an outer surface (15) of a respective strip (5) of paper, and feeds the strip (5) along a given path (P) extending at least partly along said forming beam (26);
• a loading station (18) located along said path (P) and upstream from the forming beam (26) in a traveling direction (17) of the conveyor belts (11);
• supply means (6) for transferring a respective continuous layer (20) of tobacco (7) on to an inner surface (19) of each said strip (5) at the loading station (18);
• and a gumming device (41) for gumming a lateral inner surface portion (40) of each strip (5);
• the forming beam (26) presenting, for each said conveyor belt (11), a variable-section groove (31) engaged by the conveyor belt (11) and for gradually deforming the conveyor belt (11) transversely to gradually wind the respective strip (5) about the respective layer (20) of tobacco so as firstly to form a respective tubular wrapping (38) presenting a longitudinal lateral appendix (39) projecting outwards and presenting said longitudinal lateral portion (40) of said inner surface (19), and so as secondly to turn said appendix (39) over on to the respective tubular wrapping (38);
• characterized in that said gumming device (41) is located at an intermediate point (35) of the forming beam (26);
• said gumming device (41) being located on one side only of said forming beam (26).

A machine (1) for simultaneously producing a number of cigarette rods (2), the machine (1) comprising a forming beam (26) for forming at least two cigarette rods (2);

• a conveyor belt (11) for each said cigarette rod (2), the conveyor belt (11) being brought into contact with an outer surface (15) of a respective strip (5) of paper, and feeds the strip (5) along a given path (P) extending at least partly along said forming beam (26);
• a loading station (18) located along said path (P) and upstream from the forming beam (26) in a traveling direction (17) of the conveyor belts (11);
• supply means (6) for transferring a respective continuous layer (20) of tobacco (7) on to an inner surface (19) of each said strip (5) at the loading station (18);
• and a gumming device (41) for gumming a lateral inner surface portion (40) Of each strip (5);
• the forming beam (26) presenting, for each said conveyor belt (11), a variable-section groove (31) engaged by the conveyor belt (11) and for gradually deforming the conveyor belt (11) transversely to gradually wind the respective strip (5) about the respective layer (20) of tobacco so as firstly to form a respective tubular wrapping (38) presenting a longitudinal lateral appendix (39) projecting outwards and presenting said longitudinal lateral portion (40) of said inner surface (19), and so as secondly to turn said appendix (39) over on to the respective tubular wrapping (38);
• characterized in that said gumming device (41) is located at an intermediate point (35) of the forming beam (26);
• said gumming device (41) comprising, for each said conveyor belt (11), a gumming disk (43, 44) presenting an axis (46) of rotation, and a lateral surface (47, 48) tangent, in use, to said lateral inner surface portion (40) of the respective said appendix (39);
• the gumming disks (43, 44) being both located over said forming beam (26);
• and said axis (46) extending over the forming beam (26) and crosswise to said traveling direction (17).