US3691736A - Pocket filter for air and gas purification - Google Patents

Pocket filter for air and gas purification Download PDF

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Publication number
US3691736A
US3691736A US12941A US3691736DA US3691736A US 3691736 A US3691736 A US 3691736A US 12941 A US12941 A US 12941A US 3691736D A US3691736D A US 3691736DA US 3691736 A US3691736 A US 3691736A
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US
United States
Prior art keywords
filter assembly
sidewalls
housing
strips
housings
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US12941A
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English (en)
Inventor
Gerhard Max Neumann
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Delbag Luftfilter GmbH
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Delbag Luftfilter GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Delbag Luftfilter GmbH filed Critical Delbag Luftfilter GmbH
Application granted granted Critical
Publication of US3691736A publication Critical patent/US3691736A/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D46/00—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
    • B01D46/02—Particle separators, e.g. dust precipitators, having hollow filters made of flexible material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D46/00—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
    • B01D46/02—Particle separators, e.g. dust precipitators, having hollow filters made of flexible material
    • B01D46/023—Pockets filters, i.e. multiple bag filters mounted on a common frame
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D46/00—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
    • B01D46/02—Particle separators, e.g. dust precipitators, having hollow filters made of flexible material
    • B01D46/06—Particle separators, e.g. dust precipitators, having hollow filters made of flexible material with means keeping the working surfaces flat

Definitions

  • V-shaped clamps 12 l M% 5x54 5 a v 5 03% ,M09 9 54 O B74 a fit within the pockets to hold a strip of filter material in place.
  • My present invention relates to a pocket filter for air and gas purification.
  • a known pocket filter utilizes large-surface-area multiple sack pockets arranged in a reception housing of suitable shape.
  • the manufacture of these sack pockets, which one also closed at the sides, and the joining of several sack pockets by sewing or glueing the outer edges to adjacent pockets is very expensive and accordingly uneconomical, since the air-filter sacks are mostly throw-away articles.
  • pocket filters of this type a dry filter material in strip form.
  • zig-zag wire grids are welded between upright sheet walls to receive a V-shape strip material, consisting of glass wool, cotton wool or textile thread, held in place by resilient removable frames.
  • the filter material cannot be satisfactorily sealed against the sheet wall since, on welding in the zig-zag wire grid, the sheet walls are subject to deformation. If several pocket filters of this type arranged one above or alongside the other to form built-in filter walls satisfactory sealing between individual, upright adjacent sheets of the housing is not obtainable at a high rate of dust removal.
  • These known filters are accordingly usable only for coarse filtering; however, the cost of equipment in relation to the degree of dust removal is very high.
  • the present invention has for its object to provide a pocket filter which affords a good seal between the individual housings and between the filter medium and the individual housings. It should be suitable for selective installation in filter ducting or in brickwork openings.
  • I provide a plurality of juxtaposed filtering units each comprising at least one housing with two end plates, a support grid of generally V-shaped cross-section bracketed by the two end plates to define a pair of apertured, rearwardly converging walls of a cell or pocket, and two parallel side members also extending between the end plates to define a pair of longitudinal edges for the rectangular insertion end of the pocket; each side member has an outer edge bent forward to constitute a connecting member or rib for attachment to a similar adjacent housing.
  • At least one end plate may be bent back'out of its plane at right angles to provide a cross-wall coplanar with the adjoining side members defining therewith a rectangular peripheral flange which frames the insertion end of the pocket.
  • a preferred special configuration of side member designed to provide both easy interconnection between housings and good sealing within the housing, is a strip bent along three longitudinal fold lines, i.e. (a) orthogonally forwardly at a first line near one edge of the insertion end to define the connecting rib; (b) backwardly along a second, intermediate, line through 360 to form a doubled-over portion; and (c) outwardly through less than along a third line from the back of this doubled-over portion so as to extend backwardly, at an acute angle to that portion the inwardly projecting doubled-over portion constitutes a shoulder for I retaining an internal filter clamp within the housing,
  • this backwardly extending portion forms a' sealing strip to which the support grid is connected.
  • this backwardly extending portion will conveniently be so oriented as to be in line with the arms of the V-shaped grid defining the apertured walls of the housing.
  • each side member extends beyond the end plate, by a distance corresponding to the height of the cross-wall, and is recessed beyond the end plate by removing the doubled-over portion to accommodate the cross-wall, the side members and cross-wall being joined together by welding to form the peripheral flange.
  • edges of the support grid may be bent over toform hookl-like flanges, or cuffs complementary cuffs being provided on the side members and/or the end plates to fasten the support grid.
  • Such cuffs' may of course be located on the end of the backwardly extending portion of the side member, and/or on the bottom of the inwardly bent portions of the end plate.
  • the side of members may span two or more like housings of a filtering unit separated by internal partitions which will not normally possess bent-cover edges and which can be lodged face-to-face in slits of suitable thickness in these side members.
  • the slits may correspond in depth to the width of the remaining doubled-over portion.
  • the clamp consists of two similar, generally planar wire frames interconnected at the free edges of the V by a spring member and at the apex of the V by welding or hinging.
  • the spring may be a leaf spring; by using a generally inwardly convex leaf spring provided with outwardly projecting bent portions, which can be manually compressed to facilitate insertion and removal of the clamp, it is possible to dispense with projections on the frame for this purpose.
  • the same advantage applies to the use of a generally outwardly convex wound wire spring, whose limbs can be pressed inward manually.
  • each end plate is of a V-shape conforming to I the cross-section of the support grid and has inwardly
  • I provide a mounting unit wherein a plurality of filter unit as described above lie side-by-side with their connecting members joined together.
  • Such a frame may have a rectangular central aperture, surrounded by an internally projecting web, in which the housings can be mounted and fixedly attached by their peripheral flanges to the web.
  • Such mounting-units are preferably assembled first by welding together the individual housings and subsequently by welting the resulting assembly to the mounting frame; in each instance the welding is best carried out as step-spot weldingusing point welding paste.
  • a filter assembly according to my invention may consist of two or more of such mounting units of generally rectangular shape mounted side-by-side.
  • a mounting unit can be disposed in an air duct and be provided with a sealing member (endless rubber tube, or plastic caulking compound) in the peripheral groove; additional sealing devices can be provided if necessary.
  • a sealing member endless rubber tube, or plastic caulking compound
  • FIG. 1 is a perspective exploded representation of a mounting unit according to my invention
  • FIG. 2 is an illustrationsimilar to FIG. 1 showing the filter material and an associated clamp
  • FIG. 3 is a fragmentary perspective of two individual housings joined together
  • FIGS. 4 to 6 are cross-sections of joined housings with differently constructed spring members
  • FIG. 7 is a fragmentary perspective view of a modified embodiment of a mounting unit.
  • FIG. 8 is a similar view of two mounting units set in a masonry opening.
  • FIGS. 1, 3 and 4 to 6 show a housing assembly 1 carried in a mountingframe 3 and constituting with it a mounting unit, the assembly 1 consisting of seven individual housings 2 arranged alongside.
  • Each individual housing 2 has a support member 4 formed of a wire grid.
  • FIG. 2 shows a filter mat or strip ,5, bent in a V-shape, which is inserted in the individual housing 2 and held by a clamp 6.
  • the individual housing 2 consists of an upper and a lower end'plate 7 between which the support grid 4 is mounted.
  • the insertion opening of the housing 2 is surrounded by a peripheral flange 8 including two longitudinal side members 9 which have upright forwardly bent portions or ribs 10.
  • the ribs 10 of two adjacent side members 9 are sealingly interconnected by steppoint welding.
  • the side member 9 has a blocking strip or abutment means formed by a fold or doubled-over portion 1], projection into the insertion opening, joined to an inwardly bent resilient sealing strip 12 to which the support grid 4 is attached.
  • An outwardly bent transverse edge of each end plate 7 forms a cross-wall l3 constituting one of the minor sides of the rectangular peripheral flange 8.
  • the cross-walls 13 are placed in complementary cutouts 14 of the longitudinal side members coplanar therewith, the depth of each cutout being equal to the width of the folded strip portion 11.
  • a continuous housing edge is formed by the completed flange 8 upon welding the cross-walls 13 to the side members 9.
  • Cuffs flanging 15 are provided on the edge of the sealing strip 12 for receiving the support grid 4.
  • the free edges of the end plates 7 haveorthogonally bent back portions 16, which are also provided with cuffs 17.
  • the support grids 4 have complementary inwardly directed cuffs 18 at their free edges.
  • the cuffs 18 of the support grid 4 are engaged with the cuffs l5, l7 and secured thereto by a flanging tool.
  • the support grids 4 may for instance also be connected to the individual housing 2 by spot welding or in some other manner.
  • a mounting frame 3 has a peripheral edge 19 and an inwardly projecting web 20 which forms an opening 21 corresponding to the total cross-section of the housing assembly 1.
  • the mounting frame 3 is pushed from the rear over the assembly lso that the cross-walls 13 come to rest on the web 20. They are then connected to the web by step point welding. The same thing takes place with the outermost side members 9 of the assembly 1 so that an assembly l is obtained which is sealed off completely against air leakage and seated in the mounting frame 3.
  • FIG. 2 shows, a mat of filter material 5, folded in a V-shape, is placed in each individual housing followed form a pair of rear legs 24 integral with transverse legs 25 and front legs 26. Projections 27, through which the two individual frames 22 are welded or held together by eyes not shown, are offset from the legs 24. Between the legs 26 lies'a resilient spring member 28. To insert the clamp 6, the free front legs 26 are pressed together and the clamp 6 is thrust into the opening of the housing. As FIGS. 4 to 6 show, when this takes place the legs 26 of the clamp 6 press outwardly against the sealing strip 12 of the housing. Simultaneously the blocking strips 11 prevent the clamp 6 from undergoing any unintended change of position, so that satisfactory sealing of the filter mat 5 into the individual housing 2 is maintained.
  • FIG. 5 shows a spring member in the form of an inwardly curved leaf spring 28 which has eye-like outwardly projecting bent-back portions 29, its ends being fixed to the clamp legs 26.
  • FIG. 4 shows a modified embodiment, in which legs 26 of clamp 6 are bent outwardly at 30 to facilitate compression of the clamp frame and wherein the spring member is an outwardly curved leaf spring 31 fastened to the legs 26.
  • FIG. 6 shows a further modification in which an outwardly curved wire spring 32, having two turns and leg portions 33 which can be gripped for the compression of the clamp 6, is fixed to the legs 26 as the resilient clamp spreader.
  • the periphery 19 of the mounting frame 3 has a peripheral stiffening groove 34 in which, as FIG. 8 shows, a seal 35 is placed when two or more mounting frames 3 are connected to one another by screws passing through bores 36.
  • FIG. 7 shows a modified embodiment in which there are continuous side members 37 extending over the height of several individual housings 2 forming part of a plurality of juxtaposed filtering units.
  • the outermost end plates 7 of the stack of individual housings 2 are each equipped in the aforedescribed way with the cross-wall 13, but the intermediate partitions 39 parallel to and coextensive with these end plates do not pos- 5 sess such cross-walls 13.
  • Members 37 have notches 38 extending over the width of the doubled-over blocking strip 11 and having a depth amounting to double the wall thickness of the end plates 39 which can therefore be held in pairs in the notches 38, and welded and sealed to each other and (at the notches 38) to the longitudinal side members 37.
  • a surrounding sealing lip is provided at the front edge of the rim 19 of the frame 3.
  • a filter comprising:
  • a plurality of juxtaposed filtering units each including at least one housing with an insertion opening framed by a rectangular planar flange, two parallel end plates extending rearwardly from the minor sides of the rectangular flange and terminating in the plane of the flange in two outwardly bent edges defining said minor sides, and a pair of apertured sidewalls extending rearwardly from the major sides of the rectangular flange to define a unitary grid in engagement with said end plates, the major sides of said rectangular flange being defined by a pair of parallel strips coplanar with said outwardly bent edges, said strips being orthogonally bent forwardly from said major sides beyond said sidewalls to form a pair of ribs transverse to said end plates, said ribs being bonded in fluidtight manner to corresponding neighboring ribs of adjacent housings;
  • clamping means in each housing removably retaining said sheet of filter material therein in contact with said sidewalls, said strips having portions projecting inwardly past said sidewalls to form a pair of 45 shoulders holding said clamping means in position within each housing;
  • each of said units comprises a plurality of stacked housings bracketed by said end plates, said strips being common to all the housings of a unit.
  • a filter assembly as defined in claim 1 whereiri said clamping means comprises a wire structure with separable halves and resilient means urging said halves apart toward said sidewalls.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Filtering Of Dispersed Particles In Gases (AREA)
US12941A 1969-02-26 1970-02-02 Pocket filter for air and gas purification Expired - Lifetime US3691736A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE6908374U DE6908374U (de) 1969-02-26 1969-02-26 Taschenfilter zur luft- und gasreinigung

Publications (1)

Publication Number Publication Date
US3691736A true US3691736A (en) 1972-09-19

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Family Applications (1)

Application Number Title Priority Date Filing Date
US12941A Expired - Lifetime US3691736A (en) 1969-02-26 1970-02-02 Pocket filter for air and gas purification

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US (1) US3691736A (enrdf_load_stackoverflow)
CH (1) CH505640A (enrdf_load_stackoverflow)
DE (1) DE6908374U (enrdf_load_stackoverflow)
FR (1) FR2032410B1 (enrdf_load_stackoverflow)
GB (1) GB1305812A (enrdf_load_stackoverflow)

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3830042A (en) * 1972-09-13 1974-08-20 Allied Filter Eng Inc Rectangular filter bag
US3960508A (en) * 1974-11-04 1976-06-01 Exxon Research And Engineering Company Trough-type scale traps
US4193780A (en) * 1978-03-20 1980-03-18 Industrial Air, Inc. Air filter construction
US4636232A (en) * 1985-12-16 1987-01-13 Amway Corporation Filter stack
US4743280A (en) * 1986-03-24 1988-05-10 Pappas Phillip M Air filter apparatus
US5800585A (en) * 1997-04-03 1998-09-01 Choi; Kyung-Ju Self-supporting pocket fluid filter
US6294004B1 (en) 1999-12-21 2001-09-25 Engineering Dynamics Ltd. Structures for electrostatic V-bank air filters
US6579336B1 (en) 2000-06-16 2003-06-17 Tri-Dim Filter Corporation Reversed cube air filter assembly
US20040144254A1 (en) * 2003-01-27 2004-07-29 Engineering Dynamics Ltd. Integrated air filtration unit
US20050252075A1 (en) * 2004-05-11 2005-11-17 Blue Rhino Global Sourcing, Llc Wave shaped screen for insect trap
US20070186774A1 (en) * 2000-06-02 2007-08-16 Donaldson Company, Inc. Multistage air cleaner including pulse cleaning system
USD597189S1 (en) * 2006-01-20 2009-07-28 Aaf-Mcquay Inc. Filter cassette
US20100031616A1 (en) * 2005-03-31 2010-02-11 Donaldson Company, Inc. Pulse Jet Air Cleaner Components; Features; Assemblies; and, Methods
US20100251681A1 (en) * 2009-04-02 2010-10-07 Richard Gebert Filter assembly and mounting flange extension for gas turbine filter assembly
US20120174788A1 (en) * 2011-01-11 2012-07-12 Carl Freudenberg Kg Wedge-shaped filter element with two leaf filters
CN102665855A (zh) * 2009-12-18 2012-09-12 卡菲尔有限公司 用于设备的空气吸入器
US8317890B2 (en) 2008-08-29 2012-11-27 Donaldson Company, Inc. Filter assembly; components therefor; and, methods
USD692543S1 (en) * 2011-02-10 2013-10-29 Camfil Farr, Inc. Multi-pocket bag filter
US9140492B1 (en) * 2008-06-23 2015-09-22 Scott E. Gunsaullus Paint disposal or recovery system
US20170056800A1 (en) * 2015-05-05 2017-03-02 Airgle Corporation Filter assembly for providing purified air
WO2017107092A1 (en) * 2015-12-23 2017-06-29 Shell Internationale Research Maatschappij B.V. System and method for filtering a gas-solids mixture
US10058810B2 (en) 2013-02-07 2018-08-28 Mann+Hummel Gmbh Filter device, in particular air filter
US20210069629A1 (en) * 2015-07-15 2021-03-11 Baldwin Filters, Inc. Filter with shield features
US11052342B2 (en) 2017-09-07 2021-07-06 Carl Freudenberg Kg Pocket filter element
US20220331729A1 (en) * 2021-04-19 2022-10-20 B/E Aerospace, Inc. Clogged air filter detection for galley inserts

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2011000437A1 (en) * 2009-07-03 2011-01-06 Camfil Ab Camflo gt wireframe
DE102014004810A1 (de) * 2014-04-03 2015-10-08 Carl Freudenberg Kg Taschenfilter

Cited By (37)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3830042A (en) * 1972-09-13 1974-08-20 Allied Filter Eng Inc Rectangular filter bag
US3960508A (en) * 1974-11-04 1976-06-01 Exxon Research And Engineering Company Trough-type scale traps
US4193780A (en) * 1978-03-20 1980-03-18 Industrial Air, Inc. Air filter construction
US4636232A (en) * 1985-12-16 1987-01-13 Amway Corporation Filter stack
US4743280A (en) * 1986-03-24 1988-05-10 Pappas Phillip M Air filter apparatus
US5800585A (en) * 1997-04-03 1998-09-01 Choi; Kyung-Ju Self-supporting pocket fluid filter
US6294004B1 (en) 1999-12-21 2001-09-25 Engineering Dynamics Ltd. Structures for electrostatic V-bank air filters
US20070186774A1 (en) * 2000-06-02 2007-08-16 Donaldson Company, Inc. Multistage air cleaner including pulse cleaning system
US8444748B2 (en) 2000-06-02 2013-05-21 Donaldson Company, Inc. Multistage air cleaner including pulse cleaning system
US6579336B1 (en) 2000-06-16 2003-06-17 Tri-Dim Filter Corporation Reversed cube air filter assembly
US6902603B2 (en) * 2003-01-27 2005-06-07 Engineering Dynamics Ltd. Integrated air filtration unit
US20040144254A1 (en) * 2003-01-27 2004-07-29 Engineering Dynamics Ltd. Integrated air filtration unit
US20050252075A1 (en) * 2004-05-11 2005-11-17 Blue Rhino Global Sourcing, Llc Wave shaped screen for insect trap
US20100031616A1 (en) * 2005-03-31 2010-02-11 Donaldson Company, Inc. Pulse Jet Air Cleaner Components; Features; Assemblies; and, Methods
US8951321B2 (en) 2005-03-31 2015-02-10 Donaldson Company, Inc. Pulse jet air cleaner components; features; assemblies; and, methods
USD597189S1 (en) * 2006-01-20 2009-07-28 Aaf-Mcquay Inc. Filter cassette
US9140492B1 (en) * 2008-06-23 2015-09-22 Scott E. Gunsaullus Paint disposal or recovery system
US8317890B2 (en) 2008-08-29 2012-11-27 Donaldson Company, Inc. Filter assembly; components therefor; and, methods
US9527027B2 (en) 2008-08-29 2016-12-27 Donaldson Company, Inc. Filter assembly; components therefor; and, methods
US8721757B2 (en) 2008-08-29 2014-05-13 Donaldson Company, Inc. Filter assembly; components therefor; and, methods
US20100251681A1 (en) * 2009-04-02 2010-10-07 Richard Gebert Filter assembly and mounting flange extension for gas turbine filter assembly
US8753414B2 (en) * 2009-04-02 2014-06-17 W. L. Gore & Associates, Inc. Filter assembly and mounting flange extension for gas turbine filter assembly
CN102665855A (zh) * 2009-12-18 2012-09-12 卡菲尔有限公司 用于设备的空气吸入器
CN102665855B (zh) * 2009-12-18 2015-11-25 卡菲尔有限公司 用于设备的空气吸入器
US9056270B2 (en) 2009-12-18 2015-06-16 Camfil Ab Air intake for a plant
US8858668B2 (en) * 2011-01-11 2014-10-14 Carl Freudenberg Kg Wedge-shaped filter element with two leaf filters
US20120174788A1 (en) * 2011-01-11 2012-07-12 Carl Freudenberg Kg Wedge-shaped filter element with two leaf filters
USD692543S1 (en) * 2011-02-10 2013-10-29 Camfil Farr, Inc. Multi-pocket bag filter
US10058810B2 (en) 2013-02-07 2018-08-28 Mann+Hummel Gmbh Filter device, in particular air filter
US20170056800A1 (en) * 2015-05-05 2017-03-02 Airgle Corporation Filter assembly for providing purified air
US20210069629A1 (en) * 2015-07-15 2021-03-11 Baldwin Filters, Inc. Filter with shield features
US12168193B2 (en) * 2015-07-15 2024-12-17 Baldwin Filters, Inc. Filter with shield features
WO2017107092A1 (en) * 2015-12-23 2017-06-29 Shell Internationale Research Maatschappij B.V. System and method for filtering a gas-solids mixture
US10293295B2 (en) 2015-12-23 2019-05-21 Air Products And Chemicals, Inc. System and method for filtering a gas-solids mixture
US11052342B2 (en) 2017-09-07 2021-07-06 Carl Freudenberg Kg Pocket filter element
US20220331729A1 (en) * 2021-04-19 2022-10-20 B/E Aerospace, Inc. Clogged air filter detection for galley inserts
US12390755B2 (en) * 2021-04-19 2025-08-19 B/E Aerospace Inc. Clogged air filter detection for galley inserts

Also Published As

Publication number Publication date
DE6908374U (de) 1969-07-10
CH505640A (de) 1971-04-15
GB1305812A (enrdf_load_stackoverflow) 1973-02-07
FR2032410B1 (enrdf_load_stackoverflow) 1973-08-10
FR2032410A1 (enrdf_load_stackoverflow) 1970-11-27

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