US3767050A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filtration system for liquids
Assignee: Coleco Industries Inc
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Filing: 1972-01-04
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Granted: 1973-10-23
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Expires: 1992-01-04
Abstract
Abstract A filtration system for liquids employs a sealed tank that is partially filled with sand or the like to provide a filtration bed in the lower portion thereof. An underdrain device is buried in the bed of sand and prevents particles from passing outwardly from the bed with the liquid flowing through the system. One end of a vent conduit is attached to the underdrain device from which it passses upwardly through the sand to a point near the top of the tank. Air introduced into the tank escapes automatically through the vent conduit, thus eliminating the need for the valves which are conventionally provided in the upper portion of such tank filters for the same purpose. The filtration system includes a particulate or sand filter unit coupled with a fabric type filter to remove very fine particles from the liquid removed from the liquid treated in the sand filter unit. The system is particularly adapted for use with swimming pools, and is capable of removing very fine particles from water flowing at high rates through the system.
Inventors
- 👤 N Reiner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 06:45
CPC Classifications
B; B01; B01D; B01D36/00; B01D36/02; B01D24/00; B01D24/02; B01D24/10; B01D24/12; B01D24/46; B01D24/4631; B01D35/00; B01D35/30; B01D36/001; B01D2201/00; B01D2201/08; B01D2201/087
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
464 words
In a filtration system for liquids, the combination comprising: a. a tank filter unit comprising a substantially sealed tank providing a chamber partially filled with a particulate medium to provide a filtration bed in a lower portion thereof, said tank having inlet and outlet passages from said chamber to the exterior thereof with said inlet passage opening into said chamber at a location above the normal upper surface of said filtration bed; b. a filter underdrain device having a porous filtration portion normally buried in said filtration bed and being adapted to permit liquid flow therethrough while preventing the entry of particles of said bed thereinto, and an elongated, substantially nonporous connecting portion providing a conduit extending from said filtration portion and connected to said outlet passage to provide communication therewith from the interior of said filtration portion; c. a vent conduit extending from a point adjacent the upper surface of said chamber and downwardly through said filtration bed into connection with said underdrain device, said vent conduit being open at its upper end to the upper portion of said chamber and opening at its other end into said connecting portion of said underdrain device substantially perpendicularly to the longitudinal axis of said conduit and providing an outlet for gas from said tank into fluid being discharged through said outlet passage, whereby at the point of passage past said other end of said vent conduit, water flowing therethrough has a substantial flow vector velocity along the axis of said connecting portion tending to reduce pressure within said vent conduit to facilitate escape of gas from the vicinity of said tank top, thereby eliminating pressure buildup in the upper portion of said chamber; d. a cartridge filter unit comprising a substantially sealed housing having an internal chamber with an inlet passage thereinto and an outlet passage therefrom, and a replaceable cartridge member within said housing, said cartridge member including an elongated perforated core and an axially pleated filtration element of porous fabric having pores about 2 to 22 microns in diameter, said filtration element extending about and axially along said core over the perforations thereof with the pleats of said fabric extending radially outwardly from said core, said core being closed at one end and in communication at its other end with said outlet passage of said housing so that liquid entering through said inlet passage into said housing must pass through said filtration element of said cartridge member to pass into said core and outwardly through said outlet passage; e. an interconnecting conduit between the other end of said outlet passage of said tank filter unit and said inlet passage of said cartridge unit to permit the flow of liquids therebetween; f. pump means for forcing a liquid through said system for filtration thereby.
Claim 2
Dependent Claim
464 words
In a filtration system for liquids, the combination comprising: a. a tank filter unit comprising a substantially sealed tank providing a chamber partially filled with a particulate medium to provide a filtration bed in a lower portion thereof, said tank having inlet and outlet passages from said chamber to the exterior thereof with said inlet passage opening into said chamber at a location above the normal upper surface of said filtration bed; b. a filter underdrain device having a porous filtration portion normally buried in said filtration bed and being adapted to permit liquid flow therethrough while preventing the entry of particles of said bed thereinto, and an elongated, substantially nonporous connecting portion providing a conduit extending from said filtration portion and connected to said outlet passage to provide communication therewith from the interior of said filtration portion; c. a vent conduit extending from a point adjacent the upper surface of said chamber and downwardly through said filtration bed into connection with said underdrain device, said vent conduit being open at its upper end to the upper portion of said chamber and opening at its other end into said connecting portion of said underdrain device substantially perpendicularly to the longitudinal axis of said conduit and providing an outlet for gas from said tank into fluid being discharged through said outlet passage, whereby at the point of passage past said other end of said vent conduit, water flowing therethrough has a substantial flow vector velocity along the axis of said connecting portion tending to reduce pressure within said vent conduit to facilitate escape of gas from the vicinity of said tank top, thereby eliminating pressure buildup in the upper portion of said chamber; d. a cartridge filter unit comprising a substantially sealed housing having an internal chamber with an inlet passage thereinto and an outlet passage therefrom, and a replaceable cartridge member within said housing, said cartridge member including an elongated perforated core and an axially pleated filtration element of porous fabric having pores about 2 to 22 microns in diameter, said filtration element extending about and axially along said core over the perforations thereof with the pleats of said fabric extending radially outwardly from said core, said core being closed at one end and in communication at its other end with said outlet passage of said housing so that liquid entering through said inlet passage into said housing must pass through said filtration element of said cartridge member to pass into said core and outwardly through said outlet passage; e. an interconnecting conduit between the other end of said outlet passage of said tank filter unit and said inlet passage of said cartridge unit to permit the flow of liquids therebetween; f. pump means for forcing a liquid through said system for filtration thereby.
Claim 3
Dependent Claim
48 words
The system of claim 1 wherein said filtration portion of said underdrain device comprises a tubular strainer body having a perforated sidewall, and a fabric covering of filaments plaited directly upon the exterior surface of said strainer body and extending entirely thereabout over substantially the entire length thereof.
Claim 4
Dependent Claim
16 words
The system of claim 2 wherein said fabric covering is fabricated of a synthetic resinous material.
Claim 5
Dependent Claim
16 words
The assembly of claim 3 wherein said synthetic resinous material of said fabric is a polyester.
Claim 6
Dependent Claim
33 words
The system of claim 1 wherein the top wall of said tank is generally dome-shaped, and wherein there is provided thereon a point of support adjacent the apex thereof for said vent conduit.
Claim 7
Dependent Claim
57 words
The system of claim 5 wherein said vent conduit includes a strainer head engaged in said one end thereof, said strainer head having a plurality Of openings therethrough providing a flow passage into said vent conduit, said openings being dimensioned to admit liquids while being sufficiently small to prevent passage of particles of said particulate medium therethrough.
Claim 8
Dependent Claim
228 words
The system of claim 1 additionally including a backflush valve comprising a substantially sealed valve body and a flow directing valve member moveable therewithin between filtration and backflush positions, said valve being connected to said tank filter unit, said cartridge filter unit, and said pump means, and having a waste passage outlet therefrom, in said filtration position said valve interconnecting said inlet passage of said tank filter unit with the outlet side of said pump means and said outlet passage of said tank filter unit with said inlet passage of said cartridge unit while blocking said waste passage outlet, and in said backflush position said valve interconnecting said inlet passage of said tank unit with said waste passage outlet and said outlet passage of said tank unit with said outlet side of said pump means while blocking said inlet passage of said cartridge unit, so that in said filtration position said valve directs flow along a sequential path through said inlet passage, filtration bed, and outlet passage of said tank filter unit, said interconnecting conduit, and said inlet passage, cartridge member, and outlet passage of said cartridge filter unit, and in said backflush position said valve directs flow into said outlet passage and out of said inlet passage of said tank unit without passing through said cartridge filter unit and without reversal of direction of said pump means.
Claim 9
Dependent Claim
95 words
The system of claim 1 additionally including a vent conduit within said tank filter unit extending from a point adjacent the upper surface of said chamber and downwardly through said filtration bed into connection with said underdrain device, said vent conduit being open at its upper end to the upper portion of said chamber of said tank and opening at its other end into said underdrain device and providing an outlet for gas from said tank into fluid being discharged through said outlet passage, thereby eliminating pressure buildup in the upper portion of said chamber.
Claim 10
Dependent Claim
101 words
The system of claim 7 wherein said valve body has a generally cylindrical sidewall having a multiplicity of ports equidistantly spaced axially along the length thereof, and wherein said flow directing valve member comprises a piston assembly seated, in said valve body for axial sliding movement therein between said filtration and backflush position, said piston assembly including a pair of axially spaced, disk-shaped sealing elements in sealing engagement with said sidewall, the spacing between said sealing elements causing them to encompass only two adjacent ports, establishing communication therebetween and isolating said two ports from the other ports of said valve body.
Claim 11
Dependent Claim
24 words
The system of claim 1 wherein said pleated filtration element is of a porous fabric having pores about 5 to 10 microns in diameter.
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) | 1976-10-22 | 1977-04-23 | 1977-10-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-22 | 1981-04-23 | 1981-10-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-22 | 1985-04-23 | 1985-10-23 | $7700.00 | Window Closed / Lapsed |