Back to results
US 4,508,525 AGranted
Method and apparatus for producing tobacco smoke filter having improved tar/carbon monoxide ratio
AssigneeAmerican Filtrona Corporation
InventorRichard M. Berger
Life of this patent
Estimating the term…
Abstract
A method and apparatus for producing 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.
Claims14
A method of making smoke filters comprising the steps of:
- (a) providing an axially elongated inner member of a material which is impermeable to the passage of smoke;
- (b) providing a filtering material including a multiplicity of fibrous elements;
- (c) continuously passing said inner member through an elongated bonding zone and defining an annular space around said inner member in said bonding zone;
- (d) continuously passing said filtering material into and through said annular space and, intermediate the passage of said filtering material through said bonding zone, contacting same with a bond activating agent to bond said fibrous elements of said filtering material to each other at spaced contact points, thereby forming an elongated, smoke-permeable outer member defining a tortuous path for passage of smoke therethrough;
- and
- (e) transversely severing the resulting product at selected locations to form filter elements.
3 more elements
A method of making smoke filters comprising:
- (a) providing an axially elongated inner member of a material which is impermeable to the passage of smoke;
- (b) providing a filtering material in the form of a filter paper overwrapping material in sheet form;
- (c) overwrapping said inner member with said filtering material to form an outer member around the circumference of said inner member;
- and
- (d) transversely severing the resulting product at selected locations to form filter elements.
2 more elements
A method of making smoke filters comprising the steps of:
- (a) providing a multiplicity of axially elongated inner members each of said inner members being in the form of a self-sustaining dimensionally stable reconstituted tobacco member comprising a coherent sheet of reconstituted tobacco compacted and bonded together;
- (b) providing a filtering material including a multiplicity of fibrous elements;
- (c) continuously passing said discrete inner members in axially spaced relationship through an elongated bonding zone and defining an annular space around said inner members in said bonding zone;
- (d) continuously passing said filtering material into and through said annular space and, intermediate the passage of said filtering material through said bonding zone, contacting same with a bond activating agent to bond said fibrous elements of said filtering material to each other at spaced contact points, thereby forming an elongated, smoke-permeable outer member defining a tortuous path for passage of smoke therethrough and with said bonded fibrous material also filling the spaces between the successive discrete inner members;
- and
- (e) transversely severing the resulting product at selected locations to form filter elements.
3 more elements
Apparatus for making smoke filters comprising:
- (a) means for providing an axially elongated inner member of a material which is impermeable to the passage of smoke;
- (b) means for providing a source of a filtering material including a multiplicity of fibrous elements;
- (c) means for continuously passing said inner member through an elongated bonding zone and defining an annular space around said inner member in said bonding zone;
- (d) means for continuously passing said filtering material into and through said annular space in said bonding zone;
- (e) means for feeding a bond activating agent into said bonding zone and into contact with said filtering material to bond said fibrous elements to each other at spaced contact points thereby forming an elongated, smoke-permeable, outer member defining a tortuous path for passage of smoke therethrough;
- and
- (f) means for transversely severing the resulting product at selected locations to form filter elements.
4 more elements
Apparatus for making smoke filters comprising:
- (a) means for providing an axially elongated inner member of a material which is impermeable to the passage of smoke;
- (b) means for providing a filtering material in the form of a filter paper overwrapping material in sheet form;
- (c) means for overwrapping said inner member with said filtering material to form an outer member around the circumference of said inner member;
- and
- (d) means for transversely severing the resulting product at selected locations to form filter elements.
2 more elements
Apparatus for making smoke filters comprising:
- (a) means for providing a multiplicity of axially elongated inner members, each of said inner members being in the form of a self-sustaining dimensionally stable reconstituted tobacco member comprising a coherent sheet of reconstituted tobacco compacted and bonded together;
- (b) means for providing a filtering material including a multiplicity of fibrous elements;
- (c) means for continuously passing said discrete inner members in axially spaced relationship through an elongated bonding zone and defining an annular space around said inner members in said bonding zone;
- (d) means for continuously passing said filtering material into and through said annular space and, intermediate the passage of said filtering material through said bonding zone, contacting same with a bond activating agent to bond said fibrous elements of said filtering material to each other at spaced contact points, thereby forming an elongated, smoke-permeable outer member defining a tortuous path for passage of smoke therethrough and with said bonded fibrous material also filling the spaces between the successive discrete inner members;
- and
- (e) means for transversely severing the resulting product at selected locations to form filter elements.
3 more elements
Dependencies are inferred from the claim text.