Packaging machine for packaging paper rolls

Packaging machine for packaging paper rolls, comprising:

• an operating group configured to obtain a formation of packages, with an entry station for an entrance of rolls to be packaged and of packaging sheets used for packaging, and a station for an exit of packaged rolls;
• an elevator arranged below said entry station;
• a metal structure on which said operating group is mounted, in which a plane is arranged on which a folder and a counter-folder are formed at said entrance station to fold the packaging sheets below the rolls of each package;
• wherein a conveyor is arranged for handling the packages being formed above said plane along a corresponding movement direction, and in which welding means are arranged for welding the packaging sheets after their folding;
• wherein on the counter-folder is mounted a welding bar able to perform the welding of a packaging sheet below the rolls forming each package, said welding bar being supported by a body interlocked with a mechanism which controls an exit of said welding bar through an opening made on the counter-folder and, respectively, a return of said welding bar below the counter-folder, leaving an open space allowing air to pass through said opening when the welding bar is below the counter-folder;
• and
• wherein said conveyor comprises a plurality of independent carriages, each of which is formed by a plate, is moved along an annular path which always has a section above the said plane, and on which is applied a row of teeth projecting from the plate, the carriages being controlled such that, during the formation of the packages, three carriages which follow one another along said movement direction form two adjacent compartments in which the rolls and the respective packing sheets are received, with a compartment upstream and another compartment downstream in relation to the movement direction, with a rear carriage, an intermediate carriage and a front carriage, in which the intermediate carriage forms a front side of the compartment located upstream and at a same time forms a back side of the compartment located downstream.