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US 4,357,950 AGranted
Tobacco smoke filter having improved tar/carbon monoxide ratio
AssigneeAmerican Filtrona Corporation
InventorRichard M. Berger
Life of this patent
Estimating the term…
Abstract
A tobacco smoke filter having an improved tar/carbon monoxide ratio is disclosed. The filter is obtained by sealing off the center portion of the filter with an inner member which is impermeable to the passage of smoke, thus directing all of the smoke to the periphery of the filter. In one embodiment, the inner member is formed as a thin walled tube of a material such as polypropylene, with the tube being crimped to seal one end of the tube. The crimped tube is then overwrapped with a smoke permeable material.
Claims35
Filtering means for filtering undesirable constituents from smoke comprising a filter element including:
- (a) an axially elongated outer member having an axial passage therein, said outer member consisting essentially of a filtering material and having a smoke receiving end spaced from a smoke discharging end;
- (b) sealing means for sealing off the passage to substantially prevent the axial movement of smoke through said passage and for directing the smoke entering at the smoke receiving end to pass through the filtering material of the outer member, said sealing means comprising an axially elongated inner member of smoke impermeable material coaxially disposed in relation to said outer member within said axial passage to substantially preclude the axial movement of smoke between the outer surface of said inner member and the inner surface of said outer member, said inner member being co-extensive with said axial passage;
- and
- (c) wrapping means for retaining smoke within the filtering material of the outer member as it is drawn from the smoke receiving end to the smoke discharging end, said wrapping means comprising an outer wrap disposed on the outer surface of said outer member.
1 more element
A smoke filter means including a filter element comprising:
- (a) an axially elongated, hollow outer member;
- (b) an axially elongated inner member disposed within said outer member;
- (c) said outer member comprising a filtering material and including an inner surface and an outer surface and having spaced end portions;
- (d) said inner member comprising a self-sustaining dimensionally stable reconstituted tobacco member in the form of a rod-like body comprising a coherent sheet of reconstituted tobacco compacted and bonded together;
- (e) said inner member including an outer surface and having spaced end portions, one end portion being shorter than the corresponding end of said outer member to define cavity means within said outer member and wherein said cavity is filled with the filtering material of said outer member so that said inner member is not visible at the corresponding end of said filter element;
- (f) said outer surface of said inner member being juxtaposed to said inner surface of said outer member to at least substantially preclude axial passage of smoke across the area therebetween.
3 more elements
A filtered cigarette comprising a tobacco rod and filtering means for filtering undesirable constituents from the tobacco smoke and for obtaining an improved tar/CO ratio, said filtering means comprising a filter element including:
- (a) an axially elongated outer member having an axial passage therein, said outer member consisting essentially of a filtering material and having a smoke receiving end spaced from a smoke discharging end;
- (b) sealing means for sealing off the passage to substantially prevent the axial movement of smoke through said passage and for directing the smoke entering at the smoke receiving end to pass through the filtering material of the outer member, said sealing means comprising an axially elongated inner member of smoke impermeable material coaxially disposed in relation to said outer member within said axial passage to substantially preclude the axial movement of smoke between the outer surface of said inner member and the inner surface of said outer member, said inner member being co-extensive with said axial passage;
- and
- (c) wrapping means for retaining smoke within the filtering material of the outer member as it is drawn from the smoke receiving end to the smoke discharging end, said wrapping means comprising an outer wrap disposed on the outer surface of said outer member.
1 more element
A filter rod comprising a plurality of filter elements each including:
- (a) an axially elongated outer member having an axial passage therein, said outer member comprising a filtering material and having a smoke receiving end spaced from a smoke discharging end;
- and
- (b) sealing means for sealing off the passage to prevent the axial movement of smoke from the smoke receiving end through said passage to said smoke discharging end and for directing the smoke entering said smoke receiving end to pass through the filtering material of the outer member, said sealing means comprising an axially elongated inner member of smoke impermeable material disposed within said passage to substantially preclude the axial movement of smoke between the outer surface of said inner member and the inner surface of said outer member, said inner member being co-extensive with said axial passage;
- and said filter elements being integrally connected so that the smoke receiving ends of alternating filter elements in said rod are juxtaposed to each other and the smoke discharging ends of alternating filter elements in said rod are juxtaposed to each other.
1 more element
An axially elongated smoke filter element, said filter element having a smoke receiving end for receiving smoke from a tobacco rod and a smoke discharging end for discharging this smoke, and comprising
- (a) an axially elongated outer member consisting essentially of a filtering material and having an axial passage therein;
- (b) an axially elongated hollow inner member of smoke impermeable material having an inner surface defining an internal cavity and an outer surface, said inner member being sealed at one end thereof and open at the other end thereof and coaxially disposed in relation to said outer member within said axial passage to substantially preclude the axial movement of smoke between the outer surface of the inner member and the inner surface of the outer member;
- (c) regulating means for regulating the filtration of smoke passing through said filter element comprising passage means through said inner member providing direct communication between said inner and outer surfaces of said inner member to permit passage of a limited amount of smoke directly through said inner member, said passage means being partially occluded by the filtering material of said outer member as said filter element is used, to reduce the amount of smoke passing directly through said inner member with subsequent puffs and force more of such smoke through the filtering material of said outer member;
- and
- (d) wrapping means for retaining smoke within the filtering material of the outer member as it is drawn from the smoke receiving end of the filter element to the smoke discharging end.
2 more elements
Filtering means for filtering undesirable constituents from smoke comprising a filter element including:
- (a) an axially elongated outer member having an axial passage therein, said outer member consisting essentially of a filtering material and having a smoke receiving end spaced from a smoke discharging end;
- (b) sealing means for sealing off the passage to substantially prevent the axial movement of smoke through said passage and for directing the smoke entering at the smoke receiving end to pass through the filtering material of the outer member, said sealing means comprising an axially elongated inner member of smoke impermeable material less than co-extensive with said axial passage and disposed within said axial passage to substantially preclude the axial movement of smoke between the outer surface of said inner member and the inner surface of said outer member and to leave a forward portion of the passage at the smoke discharging end of the outer member vacant;
- (c) a plug of filtering material disposed against said inner member within the vacant forward portion of said axial passage so that the plug and inner member are co-extensive with said axial passage;
- and
- (d) wrapping means for retaining smoke within the filtering material of the outer member as it is drawn from the smoke receiving end to the smoke discharging end, said wrapping means comprising an outer wrap disposed on the outer surface of said outer member.
2 more elements
Filtering means for filtering undesirable constituents from smoke comprising a filter element including:
- (a) an axially elongated outer member having an axial passage therein, said outer member consisting essentially of a filtering material and having a smoke receiving end spaced from a smoke discharging end;
- (b) sealing means for sealing off the passage to substantially prevent the axial movement of smoke through said passage and for directing the smoke entering at the smoke receiving end to pass through the filtering material of the outer member, said sealing means comprising an axially elongated inner member of smoke impermeable material coaxially disposed in relation to said outer member within said axial passage to substantially preclude the axial movement of smoke between the outer surface of said inner member and the inner surface of said outer member, said inner member being substantially co-extensive with said axial passage and comprising a tube having one end crimped and sealed together;
- and
- (c) wrapping means for retaining smoke within the filtering material of the outer member as it is drawn from the smoke receiving end to the smoke discharging end, said wrapping means comprising an outer wrap disposed on the outer surface of said outer member.
1 more element
A filtered cigarette comprising a tobacco rod and filtering means for filtering undesirable constituents from the tobacco smoke and for obtaining an improved tar/CO ratio, said filtering means comprising a filter element including:
- (a) an axially elongated outer member having an axial passage therein, said outer member consisting essentially of a filtering material and having a smoke receiving end spaced from a smoke discharging end;
- (b) sealing means for sealing off the passage to substantially prevent the axial movement of smoke through said passage and for directing the smoke entering at the smoke receiving end to pass through the filtering material of the outer member, said sealing means comprising an axially elongated inner member of smoke impermeable material coaxially disposed in relation to said outer member within said axial passage to substantially preclude the axial movement of smoke between the outer surface of said inner member and the inner surface of said outer member, said inner member being substantially co-extensive with said axial passage and comprising a tube having one end crimped and sealed together;
- and
- (c) wrapping means for retaining smoke within the filtering material of the outer member as it is drawn from the smoke receiving end to the smoke discharging end, said wrapping means comprising an outer wrap disposed on the outer surface of said outer member.
1 more element
Dependencies are inferred from the claim text.