paper material glued at the top and taken from a reel that is not illustrated in fig1 is fed by non illustrated means tangentially onto the periphery of the roller 5 at a linear speed that is less than the peripheral speed of the latter the edge of the strip 15 in contact with the roller 5 is maintained adherent therewith through suction applied via the holes 11 upstream of the area where the rollers 1 and 5 are adjacent the strip 15 is cut by a rotating knife or cutting means 16 provided peripherally with four equidistant blades 17 that cooperate with the periphery of the roller 5 for the cutting action the knife 16 given counter clockwise rotary motion separates in succession from the strip 15 bands 18 destined to connect one to the other the elements in the groups 4 because of the previously mentioned difference between the peripheral speed of the roller 5 and the linear velocity of the strip 15 the front edge of the latter slides constantly on the roller 5 in such a way that after being cut the bands suitably spaced one with respect to the other attach themselves to the said roller 5 placed in proximity to the roller 5 between the rollers 1 and 12 there is a counter rolling element that is shown generally at 19 this comprises a support member 20 keyed to a shaft or carrier means 21 parallel to the shaft 6 the support member 20 carries two identical concave plates 22 and 23 that are placed symmetrically with respect to one axial plane of the support member 20 the plate 22 is coaxial with the roller 5 and it occupies a position defined a rolling position shown at 24 the plate 22 and the.