Sub-unit of a smoking article and method for making it

Abstract

A sub-unit of a smoking article includes a tubular wrapper which extends along a main axis of extension and internally defines a containment chamber containing a filling material of the tobacco industry. The tubular wrapper has an access opening on at least one of its ends for access to the containment chamber. The sub-unit also includes at least one closing element applied to the at least one end of the tubular wrapper to define a closing wall for closing the access opening. The closing element extends transversely to the main axis of extension in such a way as to at least partly close the access opening.

1 . A sub-unit of a smoking article comprising a tubular wrapper extending along a main axis of extensions and internally defining a containment chamber containing a filling material of the tobacco industry, the tubular wrapper having an access opening on at least one of its ends for access to the containment chamber;
 wherein it comprises at least one closing element applied to the at least one end of the tubular wrapper to define a closing wall to close the access opening, the closing element extending transversely to the main axis of extension so as to at least partly close the access opening.   
     
     
         2 . The sub-unit according to  claim 1 , wherein the closing element has a substantially circular profile. 
     
     
         3 . The sub-unit according to  claim 1 , wherein the closing element has a substantially square profile. 
     
     
         4 . The sub-unit according to  claim 1 , wherein each closing element is made of flame retardant material. 
     
     
         5 . The sub-unit according to  claim 4 , wherein the flame retardant material is a metallic material. 
     
     
         6 . The sub-unit according to  claim 1 , wherein the at least one closing element is located inside the tubular wrapper and is coupled to an inside surface of the respective end portion of the tubular wrapper. 
     
     
         7 . The sub-unit according to  claim 6 , wherein the at least one closing element is shaped or deformed in such a way as to define a convex surface directed towards the containment chamber. 
     
     
         8 . The sub-unit according to  claim 6 , wherein the closing element has at least one edge portion and the closing element is coupled to the tubular wrapper by interference of the edge portion with an inside wall of the end. 
     
     
         9 . The sub-unit according to  claim 6 , wherein the closing element has at least one edge portion and the closing element is coupled to the tubular wrapper by gluing of the edge portion to an inside wall of the end. 
     
     
         10 . The sub-unit according to  claim 1 , wherein the at least one closing element is applied on the outside of the tubular wrapper and is coupled to an outside surface of the respective end of the tubular wrapper. 
     
     
         11 . The sub-unit according to  claim 10 , wherein the closing element has at least one edge portion and the closing element is coupled to the tubular wrapper by gluing of the edge portion to an outside wall of the end. 
     
     
         12 . The sub-unit according to  claim 1 , wherein the closing element has a surface extension such as to entirely cover the access opening and is provided with at least one hole or perforation for increasing the permeability of the closing element to air or gases. 
     
     
         13 . The sub-unit according to wherein the closing element has a surface extension such as to partly cover the access opening in such a way as to define uncovered portions of the access opening intended to allow air or gas to pass through. 
     
     
         14 . The sub-unit according to  claim 1 , wherein the closing element comprises a piece of sheet material having at least one edge portion which is suitably deformed to adapt to the shape of the end. 
     
     
         15 . The sub-unit according to  claim 1 , wherein the closing element comprises a porous body. 
     
     
         16 . The sub-unit according to  claim 1 , comprising a rod-shaped segment of the tobacco industry, having one end coupled and connected to a first end of the tubular wrapper defining a closing wall, transverse to the wrapping axis, at least partly closing the containment chamber, wherein the closing element is applied to a second end, opposite to the first end, of the tubular wrapper. 
     
     
         17 . (canceled) 
     
     
         18 . The sub-unit according to  claim 16 , wherein the tubular wrapper is made of rigid material and the rod-shaped segment has one end abutted against, and coupled to, a first end of the tubular wrapper defining a closing wall, transverse to the wrapping axis, at least partly closing the containment chamber, wherein the closing element is applied to a second end, opposite to the first end, of the tubular wrapper. 
     
     
         19 . (canceled) 
     
     
         20 . The sub-unit according to  claim 1 , wherein the tubular wrapper has a configuration which, at its first end, is closed by a closing base, transverse to the main axis of extension, to at least partly close the containment chamber, and wherein the closing element is applied to a second end, opposite to the first end, of the tubular wrapper. 
     
     
         21 . The sub-unit according to  claim 20 , wherein the closing base is made as one with the tubular wrapper. 
     
     
         22 . The sub-unit according to  claim 1 , wherein the tubular wrapper has two access openings, opposite to each other, on opposite ends of the tubular wrapper, for access to the containment chamber, and wherein the sub-unit comprises two closing elements, each coupled to a respective end of the tubular wrapper to at least partly close the respective access opening.