US3675778A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sludge tank with self-cleaning screen and screen for use therein
Assignee: Rexnord Industries LLC
•
Filing: 1970-09-16
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Granted: 1972-07-11
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Expires: 1990-09-16
Abstract
Abstract A conveyorized sludge tank is provided with a screen mounted at the bottom of the tank for swinging motion toward and away from the flights of the conveyor and adapted to lean against a course of the conveyor to cause the conveyor flights to continuously wipe the filtering surface of the screen. The screen is preferably formed in sections, each of which has spaced filtering strips and the filtering strips of adjacent sections diverge to form a herringbone pattern that minimizes and equalizes wear on the conveyor flights.
Inventors
- 👤 Don H Hoag
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:23
CPC Classifications
B; B01; B01D; B01D35/00; B01D35/28; B01D21/00; B01D21/0012; B01D21/02; B01D21/04; B01D21/0006
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
169 words
In filtering apparatus for separating relatively coarse objects from a liquid in which they are suspended, said apparatus being of the type that comprises a tank for containing the liquid suspension to be filtered, an endless conveyor at least partially immersed in said suspension and carrying a series of transverse wiper elements, an upstanding elongated filter member positioned in said tank with its filtering surface confronting said conveyor and being in contact with wiper elements of said conveyor, and means for driving said conveyor to cause the wiping elements thereof to move along the filtering surface of said filtering element to wipe said filtering surface, the improvement which comprises forming said filter member of a grid of elongated, straight, substantially parallel filtering strips secured to transverse supporting bars, said filtering strips being closely spaced to prevent said objects from passing therethrough and being arranged at a small angle with respect to the longitudinal dimension of said grid to prevent said filtering strips from wearing grooves in said wiper elements.
Claim 2
Dependent Claim
169 words
In filtering apparatus for separating relatively coarse objects from a liquid in which they are suspended, said apparatus being of the type that comprises a tank for containing the liquid suspension to be filtered, an endless conveyor at least partially immersed in said suspension and carrying a series of transverse wiper elements, an upstanding elongated filter member positioned in said tank with its filtering surface confronting said conveyor and being in contact with wiper elements of said conveyor, and means for driving said conveyor to cause the wiping elements thereof to move along the filtering surface of said filtering element to wipe said filtering surface, the improvement which comprises forming said filter member of a grid of elongated, straight, substantially parallel filtering strips secured to transverse supporting bars, said filtering strips being closely spaced to prevent said objects from passing therethrough and being arranged at a small angle with respect to the longitudinal dimension of said grid to prevent said filtering strips from wearing grooves in said wiper elements.
Claim 3
Dependent Claim
42 words
A filter member according to claim 1 wherein said small angle is of a magnitude such that the opposite ends of said filtering strips are laterally displaced by an amount approximately equal to the distance between the centers of said filtering strips.
Claim 4
Dependent Claim
21 words
A filter member according to claim 1 wherein said filtering strips are the cross-members of T-bars seCured to said transverse bars.
Claim 5
Dependent Claim
34 words
A filter member according to claim 1 wherein said grid is provided at one end with lifting lugs to facilitate removal of said filter member from a filter tank in which it is positioned.
Claim 6
Dependent Claim
185 words
In filtering apparatus for separating relatively coarse objects from a liquid in which they are suspended, said apparatus being of the type that comprises a tank for containing the liquid suspension to be filtered, an endless conveyor at least partially immersed in said suspension and carrying a series of transverse wiper elements, an upstanding elongated filter member positioned in said tank with its filtering surface confronting said conveyor and being in contact with wiper elements of said conveyor, and means for driving said conveyor to cause the wiping elements thereof to move along the filtering surface of said filtering element to wipe said filtering surface, the improvement which comprises forming said filter member of two or more interconnected sections, each of which comprises a grid of elongated, straight, substantially parallel filtering strips secured to transverse supporting bars, said filtering strips being closely spaced to prevent said objects from passing therethrough, the parallel filtering strips of adjacent sections diverging slightly from one end of said grid to the other to form a herringbone pattern to prevent said filter strips from wearing grooves in said wiper elements.
Claim 7
Dependent Claim
185 words
In filtering apparatus for separating relatively coarse objects from a liquid in which they are suspended, said apparatus being of the type that comprises a tank for containing the liquid suspension to be filtered, an endless conveyor at least partially immersed in said suspension and carrying a series of transverse wiper elements, an upstanding elongated filter member positioned in said tank with its filtering surface confronting said conveyor and being in contact with wiper elements of said conveyor, and means for driving said conveyor to cause the wiping elements thereof to move along the filtering surface of said filtering element to wipe said filtering surface, the improvement which comprises forming said filter member of two or more interconnected sections, each of which comprises a grid of elongated, straight, substantially parallel filtering strips secured to transverse supporting bars, said filtering strips being closely spaced to prevent said objects from passing therethrough, the parallel filtering strips of adjacent sections diverging slightly from one end of said grid to the other to form a herringbone pattern to prevent said filter strips from wearing grooves in said wiper elements.
References Cited (Backward Citations)
US1375499A
Cited
US2996189A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-11 | 1976-01-10 | 1976-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-11 | 1980-01-10 | 1980-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-11 | 1984-01-10 | 1984-07-11 | $7700.00 | Window Closed / Lapsed |