Patent US3697692A successfully refreshed from Google Patents.
Patent US3721072A successfully refreshed from Google Patents.
US3721072A
Expired / Lapsed
US
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Bonded activated carbon air filter
Assignee: Calgon Carbon Corp
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Filing: 1970-07-13
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Granted: 1973-03-20
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Expires: 1990-07-13
Abstract
Abstract A filter for removing odors, hydrocarbons, and other contaminants from air comprising activated carbon granules bonded together into a monolithic extended surface shape in the form of a wave. This type of filter is particularly useful in air handling systems where pressure drop is critical.
Inventors
- 👤 T Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 07:03
CPC Classifications
B; B01; B01D; B01D46/00; B01D46/52; B01D46/521; B01D39/00; B01D39/14; B01D39/20; B01D39/2055; B01D39/2058; B01D39/2062; B01D46/0027; B01D46/0036; B01D46/10; B01D46/30; B01D2239/00; B01D2239/06; B01D2239/069; B01D2239/08; B01D2239/086; B01D2239/12; B01D2239/1241
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
20 words
A filter as in claim 1 wherein the monolithic extended surface shape is in the form of a sine wave.
Claim 2
Dependent Claim
22 words
A filter device as in claim 1 wherein the frame is a member selected from the group of rigid and semi-rigid materials.
Claim 3
Dependent Claim
14 words
A filter device as in claim 3 wherein the frame is a semirigid material.
Claim 4
Dependent Claim
12 words
A filter device as in claim 4 wherein the frame is paperboard.
Claim 5
Dependent Claim
26 words
A filter device as in claim 1 wherein the bonding agent is a member selected from the group consisting of thermoplastic, thermosetting and solvent responsive materials.
Claim 6
Dependent Claim
15 words
A filter device as in claim 6 wherein the bonding agent is a thermoplastic material.
Claim 7
Dependent Claim
13 words
A filter device as in claim 7 wherein the bonding agent is polyethylene.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-19 | 1976-09-18 | 1977-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-19 | 1980-09-18 | 1981-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-19 | 1984-09-18 | 1985-03-20 | $7700.00 | Window Closed / Lapsed |