Apparatus and method for manufacturing paper straws

Apparatus for manufacturing straws comprising a support structure supporting:

• a feeding station to feed a strip or discrete sheets made of paper material along a feeding direction, said strip or discrete sheets extending:
• lengthwise along a first direction parallel to or coinciding with said feeding direction, and
• widthwise along a second direction orthogonal to said first direction between a first end portion and a second end portion,
• a forming station comprising:
• a conveyor extended lengthwise, along a winding axis, between an inlet portion receiving the strip or a discrete sheets, and an outlet portion allowing the movement of the strip or the discrete sheet exiting from said conveyor, said winding axis defining a winding direction which extends from the inlet portion to the outlet portion of the conveyor,
• said conveyor further comprising:
• a base extended between the inlet portion and the outlet portion of the conveyor, said base being configured for receiving in abutment the strip or the discrete sheet;
• a first lateral wall and a second lateral wall, opposite each other and extended height-wise starting from said base, said first and second lateral walls converging with respect to each other along said winding direction until said first and second lateral walls meet;
• a through opening situated at least at the outlet portion of the conveyor, said through opening defining a circular passage section laterally interposed between the first and the second lateral wall, and vertically interposed between said base and a top wall opposite said base;
• wherein said conveyor:
• receives the strip or the discrete sheet in a flat form at the inlet portion, and
• winds said strip or discrete sheet around the winding axis to define a cylindrical body made of paper material, wherein the first end portion and the second end portion face each other and are superimposed to define a mutual overlap portion at the outlet portion,
• a winding body extended along a main axis parallel to or coinciding with said winding axis and configured for receiving in abutment said cylindrical body, said winding body traversing said through opening of the conveyor;
• a constraining station configured for constraining, during a constraining step, the first end portion with the second end portion at the mutual overlapping portion to define a straw extended between a first and a second circular free edges,
• the constraining station being arranged downstream of the forming station and comprising a rotatable component configured to allow continuous advancement of the cylindrical body during said constraining step.