US 5,203,998 AGranted

Permanent backwashable filter structure

AssigneeBenian Filter Company, Inc.

InventorRobert Benian

Life of this patent

Estimating the term…

Loading patent…

Abstract

A liquid-cleaning filtering system with distillation capability has twin permanent filter assemblies, each utilizing a wire mesh filter cartridge which is backwashed using an internal sprayer nozzle assembly. During the normal operation of the filter cartridge, which is located in a pressurizable inverted bell housing, contaminates are filtered through a sheet of wire mesh arranged in a star configuration on a frame structure within the filter cartridge. The liquid filtering system is especially adapted for use in dry cleaning operations where a layer of diatomaceous earth and a layer of activated carabon deposited are on the wire mesh at the start of normal forward flow. Contaminates collect on this filter bed, thus cleaning the dry cleaning solvent. During the system's backwash cycle, filtered solvent previously collected in a steel reservoir is pressurized to provide a powerful head of pressure for backflushing each filter cartridge through its own sprayer nozzle assembly which reciprocates inside the cartridge. The high-pressure spray vigorously cleans the wire mesh of all suspended contaminants and filter bed particles. The backflushed dry cleaning solvent is directed to the distillation system which separates the solvent from the contaminants by the evaporation method.

Claims25

Dependent claims

A pressurizable filter cartridge apparatus having a central axis and a sheet of permanent mesh filter bed material arranged in a star configuration for increasing the ratio of surface-area-to-unit-volume of the cartridge apparatus, comprising:

a top cartridge plate provided with at least four elongated openings arranged in a star configuration;
a bottom cartridge plate having at least four elongated finger sections arranged in star configuration;
a plurality of outer tie rods for interconnecting the top and bottom cartridge plates, the outer tie rods being arranged concentrically about the central axis, with each outer tie rod being coupled to the bottom cartridge plate at an outer end portion of an elongated finger section thereof, cartridge plate and coupled to a portion of the top cartridge plate adjacent a respective one of the elongated slots at and outer end thereof;
a plurality of inner tie rods for interconnecting the top and bottom cartridge plates, with each such tie rod being connected to the bottom cartridge plate at a respective interfinger web section thereof and to the top cartridge plate at an inside web between two adjacent openings;
a sheet of permanent filter bed material arranged in a star configuration so as to have a number of pleated sections, the pleated sections passing on the outer sides of the outer tie rods and inner sides of the inner tie rods and forming an enclosed inner volume extending between the top and bottom filter cartridge plates;
and
top sealing means, for closing leakage paths between a top edge of the sheet of filter bed material and the top cartridge plate;
and
bottom sealing means for closing leakage paths between the bottom cartridge plate and a lower edge of the sheet of filter bed material,
the cartridge plates, tie rods, sheet of permanent bed material, and sealing means all being arranged, sized and interconnected in a manner which enables the filter bed material to be backwashed by liquid flowing from the enclosed inner volume through the sheet of filter bed material.

7 more elements

A filter assembly having a central axis and a permanent sheet of metal mesh material arranged in star configuration around the central axis, comprising:

a top frame structure;
a bottom frame structure;
a plurality of inner tie rods concentrically arranged about a central axis and rigidly interconnecting the top and bottom frame structures;
a plurality of outer tie rod members concentrically arranged about the central axis of the apparatus and coupling the top and bottom frame members;
a permanent backwashable sheet of woven metal mesh material having an inner and outer surface and a large generally porous region having myriad openings with a density of no less than about 1,000 openings per square inch, the sheet of woven mesh material being partially wrapped around the adjacent inner and outer tie rods such that the inner surface of the sheet is in contact with the outer tie rods, and the outer surface of the sheet is in contact with the inner tie rods, thereby giving the sheet a star configuration when viewed in a cross-section perpendicular to the central axis;
and
means for sealingly attaching the sheet of woven mesh material to the top and bottom frame structures to form an inner volume within the inner surface of the sheet that is substantially sealed from a volume on the opposite side of the sheet, except through the myriad openings in the porous region of the sheet.

4 more elements

Dependencies are inferred from the claim text.

Facts

Application: 07/900,003Filed 17 Jun 1992
Granted: 20 Apr 1993
Term ends: Not estimatedThe source records don’t support an estimate.

Classification9 codes

D06F 43/085
Reclaiming or recovering the solvent from a mixture of solvent and contaminants, e.g. by distilling: filtering arrangements; Filter cleaning;…
B01D 29/21
Arranged for inward flow filtration: with corrugated, folded or wound sheets
B01D 29/395
With hollow discs side by side on, or around, one or more tubes, e.g. of the leaf type: mounted axially on the tube
B01D 29/60
Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00;…:…