Packaging machine

Abstract

A product packaging machine comprises a conveyor ( 4 ) for feeding the products along an axis (D) in a feed direction (V); a grouping station ( 5 ) for the products ( 3 ) located downstream of the conveyor ( 4 ) along the feed direction (V) for grouping the products ( 3 ) into a group ( 2 ) of products ( 3 ); the group ( 2 ) has at least a first and a second layer ( 6, 7 ) of products ( 3 ); at the grouping station ( 5 ), the machine ( 1 ) comprises stacking means ( 11 ), by which at least the first and the second layer ( 6, 7 ) are stacked from the bottom up; more specifically, the stacking means ( 11 ) raise the first layer ( 6 ) from the bottom up and stack the second layer ( 7 ) from below, under the first layer ( 6 ).

What is claimed is: 
     
         1 . A product packaging machine comprising a conveyor ( 4 ) for feeding the products ( 3 ) in sequence;
 a grouping station ( 5 ) for the products ( 3 ) received in sequence from the conveyor ( 4 ), for grouping the products ( 3 ) into a group ( 2 ) of products ( 3 );   each group ( 2 ) comprises at least a first and a second layer ( 6 ,  7 ), each layer ( 6 ,  7 ) comprising one or more of the products ( 3 ) and being positioned one on top of the other;   the packaging machine ( 1 ) comprising means ( 8 ) for packing the groups ( 2 ) of products ( 3 ) to package the group ( 2 ) of products ( 3 ) in a respective pack ( 9 ), and comprising, at the grouping station ( 5 ), stacking means ( 11 ) which are designed to stack relative to a stacking axis (A) a layer ( 6 ), received later, under one or more layers ( 6 ,  7 ), received earlier, to form the required group ( 2 ) of products ( 3 );   characterized in that the stacking means ( 11 ) comprise a first and a second pair ( 26 ,  27 ) of arms ( 15 ,  16 ), located on opposite sides of the stacking axis (A) and each comprising at least a first and a second arm ( 15 ,  16 ); the first and the second arm ( 15 ,  16 ) of each pair ( 26 ,  27 ) are connected to the same first hinge (C 1 ) located at the same first end ( 15   a ,  16   a ) of the first and the second arm ( 15 ,  16 ).   
     
     
         2 . The machine according to  claim 1 , wherein the first and the second arm ( 15 ,  16 ) of each pair ( 26 ,  27 ) comprise a respective first and second profiled section ( 14   a ,  14   b ) for supporting the first and second layers ( 6 ,  7 ) of products ( 3 ), each connected at a respective second end ( 15   b ,  16   b ) of the first and the second arm ( 15 ,  16 ), opposite the first end ( 15   a ,  16   a ), by means of a respective second hinge (C 2 ); the second hinge (C 2 ) of each first and second profiled section ( 14   a ,  14   b ) allows the first and the second profiled section ( 14   a ,  14   b ) to rotate independently of the rotation of the arms ( 15 ,  16 ) about the first hinge (C 1 ). 
     
     
         3 . The machine according to  claim 1  or  2 , wherein the first and the second profiled section ( 14   a ,  14   b ) of each pair ( 26 ,  27 ) of arms ( 15 ,  16 ) rotates about the respective second hinge (C 2 ) in a direction of rotation opposite to the direction of rotation of the respective first and second arm ( 15 ,  16 ) about the first hinge (C 1 ). 
     
     
         4 . The machine according to  claim 2  or  3 , wherein the first and the second profiled section ( 14   a ,  14   b ) of each pair ( 26 ,  27 ) of arms ( 15 ,  16 ) maintains its position while the layers ( 6 ,  7 ) of products ( 3 ) are being stacked relative to the stacking axis (A). 
     
     
         5 . The machine according to any one of  claims 2  to  4 , wherein the first and the second profiled section ( 14   a ,  14   b ) of each pair ( 26 ,  27 ) of arms ( 15 ,  16 ) comprises a respective flat surface ( 17 ) for supporting the layers ( 6 ,  7 ) of products ( 3 ) and parallel to the underside contact face ( 25 ) of the layers ( 6 ,  7 ) of products ( 3 ); the flat supporting surface ( 17 ) remaining parallel to the underside contact face ( 25 ) of the layers ( 6 ,  7 ) of products ( 3 ) while the layers ( 6 ,  7 ) of products ( 3 ) are being stacked relative to the stacking axis (A). 
     
     
         6 . The machine according to any one of  claims 2  to  5 , wherein the first and the second profiled section ( 14   a ,  14   b ) of each pair ( 26 ,  27 ) of arms ( 15 ,  16 ) rotates about the second hinge (C 2 ) simultaneously with the rotation of the first and second arm ( 15 ,  16 ) about the respective first hinge (C 1 ). 
     
     
         7 . The machine according to any one of  claims 2  to  6 , wherein the first arm ( 15 ) and the first profiled section ( 14   a ) and the second arm ( 16 ) and the second profiled section ( 14   b ) of each pair ( 26 ,  27 ) constitute first and second retaining elements ( 12 ,  13 ) which move alternatingly from a first to a second operating position, raising one of either the first or the second layer ( 6 ,  7 ) from the bottom up; at the first operating position, the first and the second retaining elements ( 12 ,  13 ) alternately supporting at least one of either the first or the second layer ( 6 ,  7 ) of products ( 3 ); at the second operating position, the first and the second retaining elements ( 12 ,  13 ) alternately supporting one or more layers ( 6 ,  7 ) of products ( 3 ) received later than the layers ( 6 ,  7 ) received earlier in the first operating position, until the group ( 2 ) of products ( 3 ) is completed. 
     
     
         8 . The machine according to  claim 8 , wherein the first and the second retaining elements ( 12 ,  13 ) are coordinated with each other in such a way that the first retaining elements ( 12 ) move from the first to the second operating position while the second retaining elements ( 13 ) simultaneously move from the second to the first operating position, and vice versa. 
     
     
         9 . The machine according to any one of  claims 1  to  8 , wherein the first and the second arm ( 15 ,  16 ) of each pair ( 26 ,  27 ) rotate about the first hinge (C 1 ) by a respective quantity equal to the size of the angle of rotation (α 1 , α 2 ); from the first to the second operating position, and vice versa, the size of the angle of rotation (α 1 , α 2 ) of the first arm ( 15 ) being different from the size of the angle of rotation (α 1 , α 2 ) of the second arm ( 16 ).