Aerosol generating article with retractable heat source

Abstract

An aerosol generating article (100) having a proximal end (102) and a distal end (104), comprising an inner tubular element (105) having a mouthpiece end (107) and an opposed heat source end positioned at the distal end of the aerosol generating article, and an outer tubular element (130) extending from the proximal end of the aerosol generating article towards the distal end thereof. The inner tubular element comprises an inner wrapping sheet (109) circumscribing, in a co-axial arrangement: a combustible heat source (115) positioned towards the distal end of the aerosol generating article; an aerosol-forming substrate (120) downstream of the combustible heat source; and, typically, a void space (125) between the aerosol-forming substrate and the mouthpiece end. The outer tubular element typically circumscribes at least the mouthpiece end of the inner tubular element and the void space and terminates downstream of the heat source. The inner wrapping sheet includes a pre-twisted portion (109b) at least in the region circumscribing the void space. The arrangement provides that the distal end including the combustible heat source and the aerosol-forming substrate is readily slideable relative to the outer tubular element from an extended position having a first article length (L1), to a retracted position having a second article length (L2) that is less than the first article length and in which the void space is at least partially collapsed to an axially contracted configuration.

1 . An aerosol generating article having a proximal end and a distal end, comprising:
 an inner tubular element comprising an inner wrapping sheet circumscribing, in a co-axial arrangement:   a combustible heat source positioned towards the distal end of the aerosol generating article; and   an aerosol-forming substrate downstream of the combustible heat source; and   an outer tubular element circumscribing at least a portion of the inner tubular element;   wherein the inner wrapping sheet includes a pre-twisted portion;   
       whereby the pre-twisted portion enables deformation of the inner tubular element so that the distal end of the inner tubular element is slideable relative to the outer tubular element. 
     
     
         2 . The aerosol generating article according to  claim 1 , further comprising a mouthpiece filter at the proximal end, wherein a mouthpiece end of the inner tubular element is mounted to the mouthpiece filter. 
     
     
         3 . The aerosol generating article according to  claim 2 , further comprising a void space between the aerosol-forming substrate and the mouthpiece end. 
     
     
         4 . The aerosol generating article according to  claim 3 , wherein the outer tubular element extends from the proximal end of the aerosol generating article towards the distal end thereof, and circumscribes at least the mouthpiece end of the inner tubular element and the void space and terminates downstream of the heat source, and wherein the pre-twisted portion is at least in the region circumscribing the void space. 
     
     
         5 . The aerosol generating article according to  claim 3 , wherein the inner tubular element is slideable from an extended position having a first article length, to a retracted position having a second article length that is less than the first article length and in which the void space is at least partially collapsed to an axially contracted configuration. 
     
     
         6 . The aerosol generating article according to  claim 5 , wherein the second article length is about 90% or less than the first article length, or about 80% or less than the first article length, or about 70% or less than the first article length. 
     
     
         7 . The aerosol generating article according to  claim 2 , wherein the outer tubular element comprises an outer wrapping sheet joined to the inner tubular element only at the mouthpiece end thereof for a first circumferential wrap and joined to itself for a second wrap. 
     
     
         8 . The aerosol generating article according to  claim 7 , wherein the outer wrapping sheet is joined to itself along substantially the whole length thereof for the second wrap. 
     
     
         9 . The aerosol generating article according to  claim 1 . wherein a portion of the inner tubular element downstream of pre- twisted portion is rotationally offset relative to a portion of the inner tubular element upstream of pre-twisted portion by about 5 degrees or more, or about 15 degrees or more, or about 45 degrees or more. 
     
     
         10 . A method of manufacturing an aerosol generating article having a proximal end and a distal end, comprising:
 providing an inner tubular element comprising an inner wrapping sheet circumscribing, in a co-axial arrangement:   a combustible heat source positioned towards the distal end of the aerosol generating article; and   an aerosol-forming substrate downstream of the combustible heat source;   
       wherein the inner wrapping sheet includes a pre-twisted portion; and
 overwrapping at least a portion of the inner tubular element with an outer wrapping sheet, whereby the pre-twisted portion enables deformation of the inner tubular element so that the distal end of the inner tubular element is slideable relative to the outer tubular element. 
 
     
     
         11 . The method of  claim 10 , wherein overwrapping the outer wrapping sheet comprises, starting from a first edge of the outer wrapping sheet, adhesively joining the outer wrapping sheet to the inner tubular element only at a mouthpiece end thereof for a first circumferential wrap and adhesively joining the first wrap and a second wrap of the outer wrapping sheet along substantially the whole length of the outer wrapping sheet, thereby forming an outer tubular element extending from the proximal end of the aerosol generating article towards the distal end thereof, circumscribing at least the mouthpiece end of the inner tubular element. 
     
     
         12 . The method of  claim 10 , wherein the pre-twist is applied to the inner tubular element during the overwrapping procedure. 
     
     
         13 . The method of  claim 12 , wherein the overwrapping procedure comprises applying the outer wrapping sheet using a rotating drum. 
     
     
         14 . The method of  claim 13 , wherein the overwrapping comprises rolling the inner tubular element through a pinch between the rotating drum on which the sheet is temporarily attached and a stationary guide plate, the sheet wrapping around the inner tubular element and adhering thereto during passage through the pinch, wherein the distal end of the inner element that is not overwrapped rotates at a different rate to the more proximal end thereof circumscribed by the outer wrapping sheet, thereby inducing the twist in the inner wrapping sheet of the inner tubular element. 
     
     
         15 . The method of  claim 10 , comprising manufacturing a pair of aerosol generating articles back-to-back, including providing a singular mouthpiece filter element having first and second ends corresponding to initially conjoined first and second mouthpiece filters, wherein providing an inner tubular element comprises providing first and second inner tubular elements which are mounted to the respective first and second ends of the singular mouthpiece filter element, wherein the overwrapping of the first and second inner tubular elements is simultaneous, using a single outer wrapping sheet symmetrical about the centre of the mouthpiece filter element to form initially conjoined first and second outer tubular elements, the method including cutting through the conjoined outer tubular elements and the mouthpiece filter element to separate the conjoined articles into first and second aerosol generating articles.