Grouping unit and method to form groups of hygiene absorbent articles in a packaging machine

A grouping method to form groups (3) of hygiene absorbent articles (4) in a packaging machine (1), the grouping method comprises the steps of:

• feeding, along a grouping path (P), a conveyor (9) comprising a closed belt (10) which is wound around at least two pulleys (11) and supports a plurality of blades (14) which extend perpendicular to the belt (10) and delimit, between one another, respective pockets (12), which are each designed to hold one and only one corresponding hygiene absorbent article (4);
• feeding, in succession, single hygiene absorbent articles (4) to corresponding pockets (12) of the conveyor (9) in an input station (S1);
• removing groups (3) of hygiene absorbent articles (4) from the corresponding pockets (12) of the conveyor (9) in an output station (S2);
• and
• slowing down the movement with which each single hygiene absorbent article (4) enters the corresponding pocket (12) arranged in the input station (S1) by means of an active braking device (15), which is arranged in an area of the input station (S1);
• wherein the braking device (15) comprises a pushing element (16), which is arranged inside of the corresponding pocket (12) arranged in the input station (S1) so as to push each single hygiene absorbent article (4) entering the corresponding pocket (12) against a blade (14) that delimits the pocket (12);
• wherein the braking device (15) comprises a moving device (17), which cyclically moves the pushing element (16) between an open position and a closed position while within the corresponding pocket (12) arranged in the input station (S1) and delimited by a first blade (14a) and a second blade (14b);
• wherein when in the open position, the pushing element (16) is closer to the first blade (14a) than the second blade (14b) to allow each single hygiene absorbent article (4) to enter a space created between the pushing element (16) and the second blade (14b), and when in the closed position, the pushing element (16) is closer to the second blade (14b) than the first blade (14a) to push each single hygiene absorbent article (4) against the second blade (14b);
• and
• wherein the pushing element (16) is configured to be moved into each corresponding pocket (12) arranged in the input station (S1) and subsequently moved out of each corresponding pocket (12) when the corresponding pocket (12) is conveyed away from the input station (S1).