US4352684A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filter bag
Assignee: Dennison Manufacturing Co
•
Filing: 1981-07-06
•
Granted: 1982-10-05
•
Expires: 2001-07-06
Abstract
Abstract A filter bag for dry copiers, i.e. copiers which employ dry toners. The bag comprises a porous cover and a porous filter mass in the form of loose packing within the cover.
Inventors
- 👤 Suresh D. Amberkar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 04:01
CPC Classifications
B; B01; B01D; B01D46/00; B01D46/30; Y; Y10; Y10S; Y10S55/00; Y10S55/02
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
75 words
A filter bag comprising a porous bag cover, and a porous filter mass within said bag cover, said filter mass being in the form of loosely lofted material which has a greater internal surface area than that of said bag cover, and said loosely lofted material being puff expanded to completely fill said bag and having a density in the range from about 75 grams per cubic foot to about 250 grams per cubic foot.
Claim 2
Dependent Claim
75 words
A filter bag comprising a porous bag cover, and a porous filter mass within said bag cover, said filter mass being in the form of loosely lofted material which has a greater internal surface area than that of said bag cover, and said loosely lofted material being puff expanded to completely fill said bag and having a density in the range from about 75 grams per cubic foot to about 250 grams per cubic foot.
Claim 3
Dependent Claim
15 words
A filter bag as defined in claim 1 wherein said cover comprises a filter medium.
Claim 4
Dependent Claim
14 words
A filter bag as defined in claim 1 wherein said filter mass comprises polypropylene.
Claim 5
Dependent Claim
13 words
A filter bag as defined in claim 1 wherein said mass comprises polyester.
Claim 6
Dependent Claim
23 words
A filter bag as defined in claim 1 wherein said filter mass comprises fibers in the range of from 1 to 15 denier.
Claim 7
Dependent Claim
17 words
A filter bag as defined in claim 5 wherein the range is from 3 to 6 denier.
Claim 8
Dependent Claim
14 words
A filter bag as defined in claim 1 wherein the cover comprises polyester material.
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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) | 1985-10-04 | 1986-04-05 | 1986-10-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-10-04 | 1990-04-05 | 1990-10-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-10-04 | 1994-04-05 | 1994-10-05 | $7700.00 | Window Closed / Lapsed |