Method and system for packaging rolls of products

Abstract

A method and system for packaging rolls of products, in particular rolls of toilet and/or kitchen paper, in which a wrapping sheet is wrapped in a “U” shape around a group of products so that its two end flaps project from the group, each of the end flaps then being folded in an “L” shape so that one portion adheres to the group and the remaining end portion extends transversally to the group and adheres, at the point where they meet, to the end portion of the other flap; the flaps then being sealed to one another at their end portions to form a tubular wrapper.

1 . A method for packaging rolls of products, comprising the steps of: 
 aligning a group of rolls of products with an inverted U-shaped feed unit or compartment of a packaging unit, the compartment being angled with its opening opposite the group of rolls of products;    placing a wrapping sheet in a predetermined position between the group of rolls of products and the compartment opening;    pushing the group of rolls of products into the compartment so that it intercepts the wrapping sheet, folding the wrapping sheet in a “U” shape around the group of rolls of products and inside the compartment, the wrapping sheet, once folded into a “U” shape, having its two end flaps projecting from the compartment;    folding said flaps over the group of rolls of products to form a tubular wrapper; and    stabilizing the tubular wrapper by fixing the flaps to one another;    wherein the step of folding the flaps involves substantially folding each flap into an “L” shape so that one portion of the flap adheres to the group of rolls of products and its remaining end portion extends transversally to the group and adheres, at the point where they meet, to the end portion of the other flap; the step of stabilizing the tubular wrapper involving stably fixing the flaps to one another at the end portions and at the end of the folding step.    
   
   
       2 . The method according to  claim 1 , wherein the stabilizing step is carried out by applying heat to the end portions.  
   
   
       3 . The method according to  claim 2 , wherein the stabilizing step consists of sealing the end portions to one another.  
   
   
       4 . The method according to  claim 1 , wherein the step of folding the flaps involves simultaneously and symmetrically folding both flaps.  
   
   
       5 . A system for packaging rolls of products, comprising a packaging unit and transfer means for feeding to the packaging unit groups of rolls of products with respective wrapping sheets; the packaging unit comprising a conveyor with compartments, each having an inverted “U” shape and designed to receive, from the transfer means, a group of rolls of products with the relative wrapping sheet folded in a “U” around the group and with its two end flaps projecting from the compartment; the packaging unit also comprising folding means for folding the flaps over the group to form a tubular wrapper, and means for stabilizing the tubular wrapper by fixing the flaps to one another; wherein the folding means comprise two folding plates mobile in a direction at a right angle to the flaps, having respective heads transversal to said direction, and forming, with said heads, two jaws designed to bring together and stably grip together two respective end strips of the flaps.  
   
   
       6 . The system according to  claim 5 , wherein the stabilizing means are integrated in the heads for fixing the flaps to one another at the end portions.  
   
   
       7 . The system according to  claim 6 , wherein the stabilizing means are designed to apply heat to the end portions.  
   
   
       8 . The system according to  claim 7 , wherein the stabilizing means are designed to seal the end portions to one another.  
   
   
       9 . The system according to  claim 5 , comprising drive means for imparting to the folding plates opposite simultaneous and symmetrical movements in said direction.  
   
   
       10 . The system according to  claim 9 , wherein the drive means comprise, for each folding plate, a connecting rod hinged to the folding plate and a crank hinged to the connecting rod.  
   
   
       11 . The system according to  claim 5 , wherein the tubular wrapper stabilizing means comprise a sealing plate, housed in the head of one of the folding plates, and a pad, housed in the head of the other folding plate.  
   
   
       12 . The system according to  claim 11 , wherein the sealing plate is an electrical resistor.  
   
   
       13 . The system according to  claim 11 , wherein the pad is elastically yielding in said direction.  
   
   
       14 . The system according to  claim 13 , wherein the pad is made of silicone rubber.  
   
   
       15 . The system according to  claim 13 , wherein the pad is housed in the head of the respective folding plate with a spring that is elastically yielding in said direction inserted between the pad and the plate.  
   
   
       16 . The system according to  claim 5 , wherein the heads are at a right angle to the direction.  
   
   
       17 . The system according to  claim 11 , wherein, upon making contact with one another, the heads form a male-female connection.  
   
   
       18 . The system according to  claim 17 , wherein, of the heads, the head housing the sealing plate has a projection, whilst the head housing the pad has a recess; the projection and the recess, upon making contact with one another, forming a male-female connection.  
   
   
       19 . The system according to  claim 10 , wherein each crank is driven by a relative motor.  
   
   
       20 . The system according to  claim 10 , wherein the cranks are driven by a single central motor.