Folding roller and interfolding machine employing said roller

A folding roller (3) comprising:

• a cylindrical sleeve (3C) having a rotation axis (3A), an outer surface (3X) and an inner surface (3Y) delimiting an axial cavity (23) of the cylindrical sleeve (3C);
• an inner body (25) axially extending in the axial cavity (23) of the cylindrical sleeve (3C), the cylindrical sleeve (3C) arranged so as to rotate around the inner body (25);
• a suction chamber (23A) inside the cylindrical sleeve (3C);
• a plurality of suction holes (41, 43) extending from the outer surface (3X) up to the inner surface (3Y) of the cylindrical sleeve (3C);
• wherein the suction holes are arranged according to longitudinal alignments (42, 44) that are substantially parallel to the rotation axis (3A) of the cylindrical sleeve (3C) and angularly spaced apart with respect to one another;
• wherein inside the suction chamber (23A) a plurality of stationary shutters (37) are arranged, spaced from one another along the rotation axis (3A) of the cylindrical sleeve (3C), each shutter (37) having a closing surface (37A) co-acting with the inner surface (3Y) of the cylindrical sleeve (3C) to close selected suction holes (41) of the plurality of suction holes (41, 43), wherein the plurality of suction holes (41, 43) are subdivided into a plurality of first longitudinal alignments (42) and into a plurality of second longitudinal alignments (44), alternating with, and angularly spaced apart from one another, and wherein the plurality of suction holes (41, 43) are configured and arranged so that, during rotation of the cylindrical sleeve (3C), the selected suction holes (41) of the first longitudinal alignments (42) are closed by the shutters (37) while the remaining suction holes (43) of the second longitudinal alignments (44) are not closed by the shutters (37).