Device for closing containers made of plastic

Abstract

A system of sealing containers of plastic material for the sealing of containers having a mouth surrounded by a peripheral flap, consisting of arranging a sealing sheet on the mouth of the container to be sealed, supporting the peripheral flap on a welding mold, and applying ultrasonic vibrations on the sealing sheet, in coincidence with a mold, by means of independent sonotrodes, said mold comprising two concentric walls situated in coincidence with the peripheral flap surrounding the mouth of the container to be sealed, an internal wall allowing for the welding between the sealing sheet and the peripheral flap of the mouth, and another outer wall, of a slightly larger height, finished in an angled edge profile to cause the cutting of the sealing sheet and of said peripheral flap at a certain variable distance from the weld line between said sheet and peripheral flap.

1 . A system for sealing containers of plastic material, especially for sealing containers the mouth of which is surrounded by a peripheral flap in extension of the wall, consisting of arranging a sealing sheet on the mouth of the container or containers to be sealed, supporting the peripheral flap on a welding mold, and applying ultrasonic vibrations on the sealing sheet, in coincidence with a mold, by means of independent sonotrodes, characterized in that the mold comprises two concentric walls situated in coincidence with the peripheral flap surrounding the mouth of the container or containers to be sealed, an inner wall allowing for the welding between the sealing sheet and the peripheral flap of the mouth, and another outer wall, of a slightly larger height, finished in an angled edge profile to cause the cutting of the sealing sheet and of said peripheral flap at a certain variable distance from the weld line between said sheet and peripheral flap.  
     
     
         2 . A device for sealing containers of plastic material according to  claim 1 , characterized in that the inner wall has a continuous linear edge.  
     
     
         3 . A device for sealing containers of plastic material according to  claim 1 , characterized in that the inner wall has a broken edge.  
     
     
         4 . A device for sealing containers of plastic material according to  claim 1 , characterized in that the inner wall and the outer wall are separated and are independent.  
     
     
         5 . A device for sealing containers of plastic material according to  claim 1 , characterized in that the inner wall and the outer wall are joined, forming a single wall.  5 , characterized in that two areas are arranged between the inner profile and the outer profile, parallel to said  
     
     
         6 . A device for sealing containers of plastic material according to  claim 3 , characterized in that two areas are arranged between the inner profile and the outer profile, parallel to said profiles and inwardly from the inner profile, throughout which areas cavities are arranged in which the plastic material accumulates once it has been melted.  
     
     
         7 . A device for sealing containers of plastic material according to  claim 3 , characterized in that the edge of the inner wall is transversally located in extension of the edge of the outer wall.  
     
     
         8 . A device for sealing containers of plastic material according to  claim 5 , characterized in that two areas are arranged between the inner profile and the outer profile, parallel to said profiles and inwardly from the inner profile, throughout which areas cavities are arranged in which the plastic material accumulates once it has been melted.  
     
     
         9 . A device for sealing containers of plastic material according to  claim 5 , characterized in that the edge of the inner wall is transversally located in extension of the edge of the outer wall.