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US3810477A Expired / Lapsed US ⏱️ 0.0 years remaining

Tobacco smoke filter

Assignee: Filtrona Richmond Inc
•
Filing: 1973-04-05
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Granted: 1974-05-14
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Expires: 1993-04-05
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Abstract

Abstract Tobacco smoke filter means, particularly for use with cigarettes and the like, having improved filtration efficiencies and/or reduced costs. One embodiment increases filtration efficiency by minimizing the crimped portion of the filtering material thereby maximizing the effective filtering area. Another embodiment reduces total weight of filtering material, and thereby costs of manufacture, while still producing high level filtration efficiency by utilizing a ''''double crimp'''' thereby forming an enclosed intermediate cavity means so that the smoke must pass through the filtering material twice.

Inventors

  • 👤 R Berger
  • 👤 E Brooks

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 04:57
CPC Classifications
A; A24; A24D; A24D3/00; A24D3/04

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 398 words
A filter means including a filter element comprising: a. an axially elongated, hollow, outer member; b. an axially elongated, hollow, inner member disposed within said outer member; c. said outer member including an inner surface and an outer surface and having spaced end portions; d. said inner member comprising a filtering material and including an inner surface and an outer surface and having spaced end portions; e. integral peripheral portions of said outer surface of said inner member in juxtaposition to one end portion of said inner member being juxtaposed to portions of said inner surface of said outer member to at least substantially preclude axial passage of smoke across the area therebetween; f. the major portions of said outer surface of said inner member being spaced from said inner surface of said outer member to define first elongated cavity means therebetween; g. integral first portions of said inner member defining a first area extending across the interior of said inner member in juxtaposition to the other end portion of said inner member which offers at least as much resistance to passage of smoke as said filtering material; h. integral tapered portions of said inner member extending outwardly from said other end portion of said inner member toward said inner surface of said outer member; i. axially extending, circumferentially spaced, integral fin means surrounding said tapered portions of said inner member and including axially extending edge portions juxtaposed to said inner surface of said outer member, said fin means extending axially from said other end portion of said inner member over substantially the full axial extent of said tapered portions of said inner member; j. second portions of said inner member in juxtaposition to said one end portion of said inner member defining a second area extending across the interior of said inner member which offers less resistance to passage of smoke than the area between said peripheral portions of said inner member and said inner surface of said outer member; k. the interior of said inner member between said first and second portions defining second elongated cavity means, whereby smoke passing through said filter element between opposite ends thereof must travel through both said cavity means and through said filtering material; and l. the axial length of said fin means being from about 5 to about 25 percent of the total axial length of said inner member.
Claim 2
Dependent Claim 398 words
A filter means including a filter element comprising: a. an axially elongated, hollow, outer member; b. an axially elongated, hollow, inner member disposed within said outer member; c. said outer member including an inner surface and an outer surface and having spaced end portions; d. said inner member comprising a filtering material and including an inner surface and an outer surface and having spaced end portions; e. integral peripheral portions of said outer surface of said inner member in juxtaposition to one end portion of said inner member being juxtaposed to portions of said inner surface of said outer member to at least substantially preclude axial passage of smoke across the area therebetween; f. the major portions of said outer surface of said inner member being spaced from said inner surface of said outer member to define first elongated cavity means therebetween; g. integral first portions of said inner member defining a first area extending across the interior of said inner member in juxtaposition to the other end portion of said inner member which offers at least as much resistance to passage of smoke as said filtering material; h. integral tapered portions of said inner member extending outwardly from said other end portion of said inner member toward said inner surface of said outer member; i. axially extending, circumferentially spaced, integral fin means surrounding said tapered portions of said inner member and including axially extending edge portions juxtaposed to said inner surface of said outer member, said fin means extending axially from said other end portion of said inner member over substantially the full axial extent of said tapered portions of said inner member; j. second portions of said inner member in juxtaposition to said one end portion of said inner member defining a second area extending across the interior of said inner member which offers less resistance to passage of smoke than the area between said peripheral portions of said inner member and said inner surface of said outer member; k. the interior of said inner member between said first and second portions defining second elongated cavity means, whereby smoke passing through said filter element between opposite ends thereof must travel through both said cavity means and through said filtering material; and l. the axial length of said fin means being from about 5 to about 25 percent of the total axial length of said inner member.
Claim 3
Dependent Claim 35 words
A cigarette comprising, in combination, a tobacco rod and a filter means secured in end-to-end relationship to one end of said tobacco rod, said filter means including a filter element as defined in claim 1.
Claim 4
Dependent Claim 14 words
A filter means according to claim 1 wherein said filtering material comprises cellulose acetate.
Claim 5
Dependent Claim 97 words
The filter means of claim 1 wherein said inner member is tubular, the outer surface of one end portion of said inner member defining said peripheral portions, the other end portions of said inner member being crimped and sealed together to define said first area, spaced parts of the periphery of said crimped portions defining said fin means and contacting said inner surface of said outer member to assist in centering said inner member within said outer member, the inner surface of said one end portion of said inner member being open to define said second area.

References Cited (Backward Citations)

US3533416A Cited
US3599646A Cited
US3648711A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1977-05-13 1977-11-12 1978-05-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1981-05-13 1981-11-12 1982-05-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1985-05-13 1985-11-12 1986-05-14 $7700.00 Window Closed / Lapsed

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