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Patent US4033362A successfully refreshed from Google Patents.
US4033362A
Expired / Lapsed
US
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Filter for tobacco smoke
Assignee: F J BURRUS AND CIE
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Filing: 1975-02-26
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Granted: 1977-07-05
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Expires: 1995-02-26
Abstract
Abstract The present invention relates to a new type of filter for tobacco smoke, which filter has a diffusion portion, in which the smoke stream is separated from the outer air by means of a membrane, which is permeable to low molecular smoke constituents.
Inventors
- 👤 Sven-Olof Almqvist
- 👤 Curt R. Enzell
- 👤 Lasse O. Hjern
- 👤 Antoine Artho
- 👤 Robert Koch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 19:43
CPC Classifications
A; A24; A24D; A24D3/00; A24D3/04; A24D3/043
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
49 words
Filter for tobacco smoke, comprising a diffusion portion consisting of a membrane separating the smoke stream from the outer air and being permeable to low molecular compounds in the gaseous phase of the smoke for selective removal of low molecular compounds from said tobacco smoke to the surrounding air.
Claim 2
Dependent Claim
49 words
Filter for tobacco smoke, comprising a diffusion portion consisting of a membrane separating the smoke stream from the outer air and being permeable to low molecular compounds in the gaseous phase of the smoke for selective removal of low molecular compounds from said tobacco smoke to the surrounding air.
Claim 3
Dependent Claim
38 words
Filter according to claim 1 characterized in that it contains an insert, which forces the smoke to pass along the walls of the diffusion portion to subject as much as possible of the smoke to the diffusion process.
References Cited (Backward Citations)
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US3324861A
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US3351072A
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CH431169A
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US3512537A
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US3602232A
Cited
US3596663A
Cited
US3714949A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-07-04 | 1981-01-03 | 1981-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-04 | 1985-01-03 | 1985-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-04 | 1989-01-03 | 1989-07-05 | $7700.00 | Window Closed / Lapsed |