GRUPPO DI PIEGATURA DI UN FOGLIO CONTINUO IN MATERIALE DA IMBALLAGGIO, IN PARTICOLARE CARTA, APPLICABILE A MACCHINE CONFEZIONATRICI AUTOMATICHE E MACCHINA CONFEZIONATRICE AUTOMATICA COMPRENDENTE TALE GRUPPO DI PIEGATURA

A folding assembly (10) of a continuous sheet (F) of packaging material, in particular paper, applicable to automatic packaging machines (100) of the type comprising a sliding plane (101) for conveying a continuous sheet (F) of packaging material, in particular paper, along a conveying direction (DT), said sliding plane (101) comprising an entrance end (102) for entering the continuous sheet of paper (F) and two opposite sides (103, 104) parallel to the conveying direction (DT), and a feeding assembly (105) for feeding the continuous sheet (F) of packaging material along a feeding plane (106) which is orthogonal or substantially orthogonal to the conveying direction (DT) and defined at the entrance end (102) of the sliding plane (101), in which the continuous sheet (F) of packaging material is fed along the feeding plane (106) according to a feeding direction (DA) orthogonal or substantially orthogonal to the sliding plane (101) and is deviated of a right or a substantially right angle while passing from the feeding plane (106) to the sliding plane (101), in which the folding assembly (10) comprises, for at least one of the opposite sides (103, 104) of the sliding plane (101), a respective block (11) which is associable with at least one opposite side of the sliding plane (101) at the entrance end (102) and which is provided with a rectilinear edge (12) which, considering the folding assembly (10) in the mounting configuration on the packaging machine (100), faces the feeding plane (106) and is substantially parallel to the feeding direction (DA) so as to define a longitudinal creasing element of the continuous sheet (F) of packaging material for folding a corresponding longitudinal flap (F1, F2) thereof and in which the folding assembly (10) is characterised in that it comprises a body (13) provided with a cone-sector surface (S) which is associated with the block (11) with the vertex (V) of the cone-sector surface (S) arranged at the outlet end (12') of the rectilinear edge (12) of the continuous sheet (F) of packaging material provided with the longitudinal creasing exits and which, considering the folding assembly (10) in the mounting configuration on the packaging machine (100), has a conicity converging towards the entrance end (102) of the sliding plane (101), in which, considering the folding assembly (10) in the mounting configuration on the packaging machine (100), the cone-sector surface (S) supports the longitudinal flap (F1, F2) during the lon