Machine of variable linear structure for the formation of tubes

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 at least one 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,
• wherein the at least one finishing station comprises four idle forming rollers having a concave profile with a constant curvature and able to carry out movements of the same extent and direction according to 90° axes.

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 at least one 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,
• wherein each of the forming stations and the at least one finishing station include two vertical uprights that support two horizontal traverses configured to slide along the uprights, along each of said traverses sliding two shoes, on each of which is present a pivot that acts as a fulcrum for rotation of a unit that carries one of the forming rollers.

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 at least one 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;
• 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;
• and
• a plurality of containment stations, one of the containment stations being situated after each one of the forming stations,
• wherein each containment station includes two guides fixed to vertical uprights of one or more of the forming stations, each of which allows the translation according to an inclined axis of a shoe that carries a roller having a concave profile that is able to guide and to support the strip of sheet metal between two adjacent forming stations.