Patent ID: 8522589

Claim:
A machine for the continuous formation of tubes, the machine comprising: at least one first forming station and at least one second forming station able to progressively bend a strip of sheet metal, the at least one second forming station being subsequent to the at least one first forming station, each forming station including two pairs of idle forming rollers configured to carry out rototranslational movements of a same extent and in opposite directions, each of lower rollers of the idle forming rollers having an elliptical profile having a decreasing curvature from an outside edge to an inside edge of each lower roller, each of upper rollers of the idle forming rollers of the first forming station having an elliptical profile having increasing curvature from an outside edge to an inside edge of each upper roller, each of upper rollers of the idle forming rollers of the at least one second forming station having a circular profile; and at least one finishing station configured to bring together edges of the bent strip of sheet metal, the forming stations and the at least one finishing station being disposed in sequence with respect to each other in a linear configuration.