Packaging machine and method for closing containers with lids

Abstract

The invention relates to a method for closing already preformed and separated containers ( 19 ), for example trays, with a lid foil ( 24 ) in a closing station ( 3 ). The invention is characterized in that a deep-drawable foil is used as lid foil ( 24 ), that the lid foil ( 24 ) is deep-drawn in a forming means ( 23 ) of the packaging machine ( 1 ), and that the deep-drawing of the lid foil ( 24 ) is accomplished before the containers ( 19 ) are closed with the lid foil ( 24 ). The invention also relates to a packaging machine ( 1 ) suited for carrying out such a method.

1 . A method for closing already preformed and separated containers with a lid foil in a closing station of a packaging machine, the method comprising:
 deep-drawing the lid foil with a forming device of the packaging machine; and   closing the containers with the lid foil in the closing station;   wherein for each container, the deep-drawing is performed prior to the closing.   
     
     
         2 . The method according to  claim 1  further comprising heating the lid foil upstream of the forming device and/or in the forming device. 
     
     
         3 . The method according to  claim 1  wherein the deep-drawing is performed such that the lid foil is deep-drawn at least in sections towards a side of the lid foil facing the containers during the closing. 
     
     
         4 . The method according to  claim 1  wherein the deep-drawing is performed such that the lid foil is deep-drawn at least in sections towards a side of the lid foil facing away from the containers during the closing. 
     
     
         5 . The method according to  claim 1  wherein for each container the deep-drawing is performed such that at least one concave and/or one convex section is formed on a side of the lid foil facing the container during the closing. 
     
     
         6 . The method according to  claim 1  wherein the deep-drawing is carried out in the closing station. 
     
     
         7 . The method according to  claim 1  wherein the lid foil comprises a flexible foil or a hard foil. 
     
     
         8 . The method according to  claim 1  wherein the lid foil comprises a multilayer foil. 
     
     
         9 . The method according to  claim 1  wherein for each container the closing comprises placing the lid foil onto the container by a form fit. 
     
     
         10 . The method according to  claim 1  wherein for each container the closing comprises sealing the lid foil onto the container. 
     
     
         11 . The method according to  claim 10  wherein, after sealing the lid foil onto the containers, the lid foil is moved along by movement of the closed containers. 
     
     
         12 . A packaging machine for closing already preformed and separated containers with a lid foil, the packaging machine comprising:
 a forming device configured to deep draw the lid foil to form lid sections; and   a closing station for closing the containers with the lid sections;   wherein the packaging machine is operated such that, for each container, a lid section is formed prior to closing the container with the lid section.   
     
     
         13 . The packaging machine according to  claim 12  wherein, for each container, the forming device is configured to form at least one concave and/or one convex section on a side of the lid foil facing the container during the closing of the container at the closing station. 
     
     
         14 . The packaging machine according to  claim 12  wherein the forming device comprises an exchangeable insert for deforming the lid foil. 
     
     
         15 . The packaging machine according to  claim 12  further comprising a conveyor device for conveying the lid foil, and a transport device for transporting the containers. 
     
     
         16 . The packaging machine according to  claim 15  wherein the conveyor device comprises a clamp chain. 
     
     
         17 . The packaging machine according to  claim 12  wherein the closing station comprises a tool for placing and/or sealing the lid foil onto the containers. 
     
     
         18 . The packaging machine according to  claim 17  wherein the tool comprises a lower tool and an upper tool, wherein at least one of the lower tool and the upper tool is movable with respect to the other of the lower tool and the upper tool. 
     
     
         19 . The packaging machine according to  claim 18  wherein the lower tool and the upper tool are configured to be spaced apart by the relative movement at least far enough to correspond to the sum of a height of a container and a height of a lid section of the lid foil. 
     
     
         20 . The packaging machine according to  claim 12  wherein the forming device is located at the closing station.