Stacking device

Abstract

The invention relates to a stacking device for continuously forming stacks ( 12 a - e ) of bags ( 18 a ), which bags are continuously fed in at least one bag strand ( 16 a,d - e ), which comprises at least one bag row ( 14 a ) and which is endless or cut through after each series of a defined number of bags, the stacking device comprising: at least one stack base ( 24 a - e, 24′ a - b ), which is moved back and forth in a stacking motion ( 22 a - e, 22′ a ) parallel to a stack layer direction ( 20 a ) at least during the formation of a stack ( 12 a - e ); a bag-feeding means (26 a - d ), which lays the at least one bag strand (16 a,d - e ) on the stack base ( 24 a - e, 24′ a - b ) in such a way that the bag strand ( 16 a,d - e ) bends at least substantially because of the stacking motion ( 22 a - e, 22′ a ) after each series of a number of bags that forms a stack layer ( 28 a,c - d ) and forms zig-zag-shaped stack layers ( 28 a,c - d ) or that the bag strand ( 16 a,d - e ) is layered at least substantially because of the stacking motion ( 22 a - e , 22′ a ) with matching bag orientation into stack layers ( 28 a,c - d ) having the number of bags that forms the stack layer ( 28 a,c - d ); and at least one stack-transporting means ( 30 a - e, 30′ a - b ) for transporting the stacks ( 12 a - e ) out of the region of influence of the stacking motion ( 22 a - e, 22′ a ) after a specified number of stack layers has been reached. According to the invention a first driving unit ( 32 a - e, 32′ a - b ) for driving at least one stacking motion ( 22 a - e ) is provided and a further driving unit ( 32′ a - e, 32 a - b ) for driving at least one transporting motion ( 34 a - e, 34′ a ) of at least one stack-transporting means ( 30 a - e, 30′ a - b ) is provided.

1 . A stacking device for continuously forming stacks ( 12   a - f ) of bags ( 18   a ) fed continuously in at least one string of bags ( 16   a; c - f ) that has at least one row of bags ( 14   a ) and is endless and/or severed after in each case a defined number of bags, the stacking device comprising at least one stack base ( 24   a - f ,  24 ′ a; b ) that is moved back and forth in a stacking movement ( 22   a - e ,  22 ′ a ) parallel to a stack layer direction ( 20   a ) at least during formation of a stack ( 12   a - f ), a bag feeding means ( 26   a - d, f ) which deposits the at least one string of bags ( 16   a; d - f ) on the stack base ( 24   a - f ,  24 ′ a;b ) such that the string of bags ( 16   a; d - f ) deviates, at least substantially on account of the stacking movement ( 22   a - e ), in each case after a number of bags that forms a stack layer ( 28   a; c - d ), and forms zigzag-shaped stack layers ( 28   a; c - d ), or such that the string of bags ( 16   a; d - f ) is piled up with a consistent bag orientation, at least substantially on account of the stacking movement ( 22   a - e ,  22 ′ a ), in stack layers ( 28   a; c - d ) with the number of bags that forms the stack layer ( 28   a; c - d ), at least one stack transporting means ( 30   a; c - d ) for transporting the stacks ( 12   a - f ) out of an area of influence of the stacking movement ( 22   a - e ;  22 ′ a ) once a defined number of stack layers has been reached, a first drive unit ( 32   a - e ,  32 ′ a, b ) configured to drive at least one stacking movement ( 22   a - e ), and a second drive unit ( 32 ′ a - e ,  32   a, b ) configured to drive at least one transporting movement ( 34   a - e ,  34 ′ a ) of at least one stack transporting means ( 30   a - e ,  30 ′ a, b ). 
     
     
         2 . The stacking device as claimed in  claim 1 , further comprising a control unit ( 38   a ) configured to control a stroke ( 40   a ) and/or a speed ( 42   a ) of the stacking movement ( 22   a,    22 ′ a ) in at least one operating mode at least in dependence on a number of bags and/or length ( 44   a ) of a stack layer ( 28   a ) in the stack layer direction ( 20   a ), a feeding speed ( 46   a;    46   f ) of the string of bags ( 16   a ) and/or an achieved stack height ( 48   a;    12   f ) of the stack ( 12   a;    48   f ). 
     
     
         3 . The stacking device as claimed in  claim 1 , characterized in that at least one of the first and second drive units ( 32   a - b ,  32 ′ a, b ) is configured to drive a stacking movement ( 22   a, b ,  22 ′ a ) and a transporting movement ( 34   a, b ,  34 ′ a ). 
     
     
         4 . The stacking device as claimed in  claim 1 , characterized by at least two stack bases ( 24   a; b ,  24 ′ a; b ) and at least two stack transporting means ( 30   a; b ,  30 ′ a; b ), wherein stack bases ( 24   a; b ,  24 ′ a; b ) and stack transporting means ( 30   a; b ,  30 ′ a; b ) each form stack carriers ( 50   a; b ,  50 ′ a; b ) that are drivable by a common drive unit ( 32   a; b ,  32 ′ a; b ). 
     
     
         5 . The stacking device as claimed in  claim 4 , characterized in that the stack carriers ( 50   b,    50 ′ b ) and/or stop means ( 36   b,    36 ′ b ) of the stack carriers ( 50   b,    50 ′ b ) are mounted on a mounting device ( 54   b ) and are configured to be pushed and/or folded away out of a transporting region ( 56   b ) for the return transport of the stack carriers ( 50   b,    50 ′ b ) counter to a transporting direction ( 52   b ). 
     
     
         6 . The stacking device as claimed in  claim 1 , characterized in that one of the first and second drive units ( 32   c - e ,  32 ′ c - e ) drives only the stacking movement ( 22   c - e ) or only the transporting movement ( 34   c - e ). 
     
     
         7 . The stacking device as claimed in  claim 6 , characterized in that the stack base ( 24   c ) is formed by a first belt element ( 58   c ) and the stack transporting means ( 30   c ) is formed by a further, second belt element ( 60   c ) adjoining the first belt element ( 58   c ). 
     
     
         8 . The stacking device as claimed in  claim 6 , characterized in that the stack transporting means ( 30   d ) is configured to transport stacks ( 12   d ) out of a stack forming region ( 62   d ) to an onward transporting means ( 64   d ). 
     
     
         9 . The stacking device as claimed in  claim 6 , characterized in that the stack base ( 24   e ) forms the stack transporting means ( 30   e ) for transporting stacks ( 12   e ) and is mounted under the stacks ( 12   e ) and configured to be folded away for transport in the direction of a weight force ( 66   e ) and/or beneath the stacks ( 12   e ) so as to be able to be pulled and/or pivoted away for transport transversely to the direction of the weight force ( 66   e ). 
     
     
         10 . The stacking device as claimed in  claim 1 , characterized in that the bag feeding means ( 26   f ) has a brake means ( 86   f ) which, in at least one operating state, is configured to exert, on at least one portion ( 88   f ) of the string of bags ( 16   f ), a braking force ( 90   f ) with at least one force component in the opposite direction to a direction of movement ( 92   f ) of the portion ( 88   f ) of the string of bags. 
     
     
         11 . A packing machine ( 68   a ) having a stacking device ( 10   a - e ) as claimed in  claim 1 . 
     
     
         12 . A method for continuously forming stacks ( 12   a - e ) of bags ( 18   a ) fed continuously in at least one string of bags ( 16   a; d - e ) that has at least one row of bags ( 14   a ) and is endless or severed after in each case a defined number of bags, said string of bags ( 16   a; d - e ) being deposited by a bag feeding means ( 26   a - d ) on at least one stack base ( 24   a - e ,  24 ′ a; b ) that is moved back and forth in a stacking movement ( 22   a - e ,  22 ′ a ) parallel to a stack layer direction ( 20   a ) at least during the formation of a stack ( 12   a - e ), such that the string of bags ( 16   a; d - e ) deviates, on account of the stacking movement ( 22   a - e ,  22 ′ a ), in each case after a number of bags that forms a stack layer ( 28   a; c; d ), and forms zigzag-shaped stack layers ( 28   a; c; d ), or such that the string of bags ( 16   a; d; e ) is piled up with a consistent bag orientation, on account of the stacking movement ( 22   a - e ,  22 ′ a ), in stack layers ( 28   a; c; d ) with the number of bags that forms the stack layer ( 28   a; c; d ), and the stack ( 12   a - e ) is moved out of the area of influence of the stacking movement ( 22   a - e ) by way of at least one stack transporting means ( 30   a - e ,  30 ′ a; b ) for transporting the stacks ( 12   a - e ) once a defined number of stack layers has been reached, characterized in that a first drive unit ( 32   a - e ,  32 ′ a; b ) drives the stacking movement ( 22   a - e ) and a further drive unit ( 32 ′ a - e ,  32   a; b ) drives a transporting movement ( 34   a - e ,  34 ′ a ) of at least one stack transporting means ( 30   a - e ,  30 ′ a; b ).