Variable dilution filter

Abstract

Smoking article (10) has a filter mouthpiece (14) with a first stage filter element (18) and second stage filter element (19). First stage filter element (18) is rigidly attached to tipping paper (22). Second stage filter element (19) is free to move longitudinally in mouthpiece (14) and may be made to move axially by tapping the cigarette, thus, covering some of the ventilation holes (16) and changing the smoke to air ratio and the flavor.

I claim: 
     
       1. In a smoking article the improvements which comprise: a filter mouthpiece attached to one end of said smoking article by air impervious tipping paper.[.;.]. .Iadd.having .Iaddend.   a second stage filter means mounted in said mouthpiece behind the tobacco portion of said smoking article and free to move in an axial direction in said mouthpiece in response to tapping said mouthpiece on a hard surface;   a first stage filter means rigidly mounted in said mouthpiece behind said second stage filter means such that there is space for axial movement of said second stage filter; and   ventilation holes in said air impervious tipping paper forward of said first stage filter and behind the tobacco portion of said smoking article.   
     
     
       2. A smoking article as in claim 1 wherein a third stage filter means is rigidly mounted in said mouthpiece forward of said second stage filter means and behind the tobacco portion of said smoking article. 
     
     
       3. A smoking article as in claim 1 wherein said ventilation holes are located immediately behind the tobacco portion of said smoking article. 
     
     
       4. A smoking article as in claim 1 or 2 wherein said filter means are enclosed in a porous plug wrap. 
     
     
       5. A smoking article as in claim 1 or 2 wherein said filter means are non-wrapped acetate filters. 
     
     
       6. A filter mouthpiece comprising: an air impervious outer shell;   a third stage filter means rigidly mounted near one end of said outer shell;   a first stage filter means rigidly mounted near the opposite end of said outer shell;   a second stage filter means mounted in said mouthpiece between said first and third stage filter means and free to move axially in said mouthpiece in response to tapping said mouthpiece on a hard surface; and   ventilation holes in said air impervious outer shell between said first stage and third stage filter means.   
     
     
       7. A smoking article as in claim 1 or 2 .[.or 6.]. wherein said ventilation holes are located immediately forward of said first stage filter means. 
     
     
       8. A smoking article as in claim 2 .[.or 6.]. wherein said ventilation holes are located immediately behind said third stage filter means. .Iadd. 
     
     
       9.  A filter mouthpiece as in claim 6 wherein said ventilation holes are located immediately forward of said first stage filter means. .Iaddend. .Iadd.10. A filter mouthpiece as in claim 6 wherein said ventilation holes are located immediately behind said third stage filter means. .Iaddend. .Iadd.11. A filter mouthpiece as in claim 6 wherein said filter means are enclosed in a porous plug wrap. .Iaddend. .Iadd.12. A filter mouthpiece as in claim 6 wherein said filter means are non-wrapped acetate filters. .Iaddend. .Iadd.13. A filter mouthpiece for a smoking article, said mouthpiece having a forward end to be disposed to receive smoke drawn into the mouthpiece, and a rearward end to be received in the mouth, consisting essentially of: tipping paper formed into a cylinder and adapted to be attached to a smoking cylinder at its forward end and to define the exterior wall of said mouthpiece;   a first cylindrical filter element that is disposed in the cylinder formed by said tipping paper at the rearward end of said mouthpiece and that is rigidly secured to the inner surface of the tipping paper,   a second cylindrical filter element that is disposed in the cylinder formed by said tipping paper at its forward end, in spaced relation to at least one of said forward end of the mouthpiece and said first filter element, to define a cylindrical chamber within said mouthpiece that is bounded by and extends to the inner surface of said tipping paper,   said second filter element is free to move in an axial direction within said cylindrical tipping paper, in response to tapping said mouthpiece on a hard surface, and   said tipping paper having at least one aperture that can communicate with said chamber to admit air to said chamber. .Iaddend. .Iadd.14. The filter mouthpiece of claim 13 wherein both of said filter elements are enclosed respectively in a cylindrical porous plug wrap, wherein the plug wrap about said first filter element is rigidly secured to the inner surface of said tipping paper. .Iaddend. .Iadd.15. The mouthpiece of claim 13 wherein said second filter element is spaced from said first filter element, to define said chamber between said two filter elements. .Iaddend. .Iadd.16. The filter mouthpiece of claim 13 wherein said second filter element is free to move in an axial direction within said cylindrical tipping paper, in response to tapping the rearward end of said mouthpiece on a hard surface, and wherein after causing such movement to occur, said second filter element has been moved toward said first filter element and is spaced from a said smoking cylinder and from the forward end of said mouthpiece. .Iaddend. .Iadd.17. The filter mouthpiece of claim 16 wherein said second filter element is free to move in an axial direction within said cylindrical tipping paper, in response to tapping the forward end of either of said mouthpiece or of an attached smoking cylinder, on a hard surface. .Iaddend. .Iadd.18. The filter mouthpiece of claim 13 comprising a third cylindrical filter element that is rigidly secured in place inside said cylindrical tipping paper, at the forward end of said mouthpiece, for abutment against the smoking material in an attached smoking cylinder. .Iaddend. .Iadd.19. A filter cigarette comprising a smoking cylinder and, attached to one end of said smoking cylinder, a filter mouthpiece according to claim 13. .Iaddend.