US3825124A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filter elements for continuous filters
Assignee: Envirotech Corp
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Filing: 1970-07-27
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Granted: 1974-07-23
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Expires: 1990-07-27
Abstract
Abstract A plurality of concave filtering elements are fixed about the periphery of a rotary filter drum so that the mouths of the elements are open and the closed ends of the elements are directed substantially radially inward of the drum. As the drum rotates in submergence in a slurry, solids are collected in the elements by applying suction to the elements to draw the liquid therethrough; to discharge the collected solids, the elements are everted by reversing the pressure thereon.
Inventors
- 👤 S Davis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 06:27
CPC Classifications
B; B01; B01D; B01D33/00; B01D33/27; B01D33/44; B01D33/48; B01D33/52; B01D2201/00; B01D2201/02; B01D2201/28; B01D2201/282
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
164 words
A rotary drum filter comprising: a. a tank adapted to hold a body of slurry; b. a drum mounted in said tank for rotation therein about the drum axis; c. a plurality of apertures formed through the curved sidewall of said drum between the ends thereof and in spaced relationship; d. a plurality of individual filtering elements each of which has an elongate concave body which is made from flexible filter medium and which has one open end whose diameter is less than the length of said body; e. means securing said open end of one of said elements into each of said apertures in said sidewall so that said bodies of said elements may extend substantially radially inward of the drum; f. means for establishing a pressure differential across said aperture between the outside of said drum and the inside thereof; and g. means for selectively reversing said pressure differential thereby to evert said bodies of said filtering elements through their respective apertures.
Claim 2
Dependent Claim
164 words
A rotary drum filter comprising: a. a tank adapted to hold a body of slurry; b. a drum mounted in said tank for rotation therein about the drum axis; c. a plurality of apertures formed through the curved sidewall of said drum between the ends thereof and in spaced relationship; d. a plurality of individual filtering elements each of which has an elongate concave body which is made from flexible filter medium and which has one open end whose diameter is less than the length of said body; e. means securing said open end of one of said elements into each of said apertures in said sidewall so that said bodies of said elements may extend substantially radially inward of the drum; f. means for establishing a pressure differential across said aperture between the outside of said drum and the inside thereof; and g. means for selectively reversing said pressure differential thereby to evert said bodies of said filtering elements through their respective apertures.
Claim 3
Dependent Claim
46 words
A rotary drum filter according to claim 1 wherein said means securing said open ends into said apertures includes outwardly extending flanges fixed to the drum sidewall surrounding each of said apertures and said open ends are wrapped back over said flanges and are fixed thereto.
Claim 4
Dependent Claim
52 words
A rotary drum filter according to claim 1 further including means for supporting the bodies of each of said filtering elements when said elements are extended inward of the drum, said support means comprising a perforate, substantially inelastic sheath which surrounds said filtering element and which is supported from said drum sidewall.
Claim 5
Dependent Claim
32 words
A rotary drum filter according to claim 1 wherein said means for establishing a pressure differential across said apertures comprises piping disposed within said drum to communicate vacuum to said filtering elements.
Claim 6
Dependent Claim
51 words
A rotary drum filter according to claim 1 further including means for supporting the bodies of each of said filtering elements when said elements are extended inward of the drum, said support means comprising a conical spring which surrounds said filtering element body and which is fixed at side drum sidewall.
Claim 7
Dependent Claim
23 words
A rotary drum filter according to claim 1 wherein said drum is mounted for total submergence in the slurry held in said tank.
Claim 8
Dependent Claim
68 words
A rotary drum filter according to claim 1 in which said means for establishing a pressure differential across said apertures comprises a plurality of chambers formed inside said drum with at least one of said apertures providing communication between the interior of one of said chambers and the outside of said drum, and there is provided pipiNg interconnecting each of said chambers with a source of reduced pressure.
Claim 9
Dependent Claim
26 words
A rotary drum filter according to claim 7 in which communication between each chamber and the exterior of said drum is provided through a single aperture.
Claim 10
Dependent Claim
27 words
A rotary drum filter according to claim 7 in which each of said chambers communicates with the exterior of said drum simultaneously through a plurality of apertures.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-07-22 | 1978-01-21 | 1978-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-22 | 1982-01-21 | 1982-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-22 | 1986-01-21 | 1986-07-23 | $7700.00 | Window Closed / Lapsed |