US2862624A - Filter elements - Google Patents

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Publication number
US2862624A
US2862624A US503953A US50395355A US2862624A US 2862624 A US2862624 A US 2862624A US 503953 A US503953 A US 503953A US 50395355 A US50395355 A US 50395355A US 2862624 A US2862624 A US 2862624A
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US
United States
Prior art keywords
lines
filter
pleats
fins
fold
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
US503953A
Inventor
Stokes Edward Arthur
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.)
Vokes Ltd
Original Assignee
Vokes Ltd
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
Priority to GB11554/54A priority Critical patent/GB764702A/en
Application filed by Vokes Ltd filed Critical Vokes Ltd
Priority to US503953A priority patent/US2862624A/en
Application granted granted Critical
Publication of US2862624A publication Critical patent/US2862624A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D46/00Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
    • B01D46/52Particle separators, e.g. dust precipitators, using filters embodying folded corrugated or wound sheet material
    • B01D46/521Particle separators, e.g. dust precipitators, using filters embodying folded corrugated or wound sheet material using folded, pleated material
    • B01D46/522Particle separators, e.g. dust precipitators, using filters embodying folded corrugated or wound sheet material using folded, pleated material with specific folds, e.g. having different lengths
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D29/00Other filters with filtering elements stationary during filtration, e.g. pressure or suction filters, or filtering elements therefor
    • B01D29/11Other filters with filtering elements stationary during filtration, e.g. pressure or suction filters, or filtering elements therefor with bag, cage, hose, tube, sleeve or like filtering elements
    • B01D29/111Making filtering elements
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D29/00Other filters with filtering elements stationary during filtration, e.g. pressure or suction filters, or filtering elements therefor
    • B01D29/11Other filters with filtering elements stationary during filtration, e.g. pressure or suction filters, or filtering elements therefor with bag, cage, hose, tube, sleeve or like filtering elements
    • B01D29/13Supported filter elements
    • B01D29/15Supported filter elements arranged for inward flow filtration
    • B01D29/21Supported filter elements arranged for inward flow filtration with corrugated, folded or wound sheets
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D46/00Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
    • B01D46/54Particle separators, e.g. dust precipitators, using ultra-fine filter sheets or diaphragms
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2201/00Details relating to filtering apparatus
    • B01D2201/12Pleated filters
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00Stock material or miscellaneous articles
    • Y10T428/24Structurally defined web or sheet [e.g., overall dimension, etc.]
    • Y10T428/24628Nonplanar uniform thickness material
    • Y10T428/24669Aligned or parallel nonplanarities
    • Y10T428/24686Pleats or otherwise parallel adjacent folds

Description

'Dec.2,1958 E. A. STOKES 2,862,624
FILTER ELEMENTS Filed April 26, 1955 ABCDaE C D E F U U P [)0 N DOWN 00 UP UP DOWN I 7 I K7 Y Ed 2.
f UP
DOWN Up r ?4 '3 v U P DOWN \/\7\7\7 DOWN 1 DOWN I :00 WN r DOWN 1 DOWN.
m VEMraQ fan/44 04 J;'0K
United StatesPatent 2,862,624 FILTER ELEMENTS Edward Arthur Stokes, Guildford, England, assignor to Vokes Limited, Guildford, England Application April 26, 1955, Serial No. 503,953
- 2 Claims. or. 210-493 such as paper or compressed fibre, which have little inherent rigidity it is often necessary to support the fins by means of wire gauze or by a grid or the like in order to prevent the side walls of adjacent fins from contacting one another and becoming ineffective as they are distended by the pressure of the fluid being filtered. In the case of expendable elements it is not uncommon for the cost of the element supporting medium or structure to exceed by far the cost of the filtering medium itself.
It is the object of the present invention to provide an element of the finned or pleated type, which requires little or no support except at the periphery, but which is capable of maintaining the walls of each fin or pleat in proper spaced relationship under ordinary conditions of use.
According to the invention a finned or pleated filter element is provided with series of corrugations or zig-zag folds substantially normal to the ordinary lines of fold of the fins or pleats, the ordinary lines of fold of the fins or pleats being modified from straight lines to appropriate zig-zag lines so that the apices of the fins or pleats are maintained apart while the walls of the fins or pleats are stiffened by the corrugated or zig-zag folded form thereof.
Put in another way a filter element according to the invention is comprised by at least one sheet of filtering medium formed with pleats or fins by folding the sheet in alternately directed bends in zig-zag fashion, the folded sheet being then folded inv similar zig-zag fashion substantially at right angles to the first lines of fold, the said first lines of fold being then modified from parallel straight lines to parallel zig-zag lines, whereby the fins or pleats are strengthened by folds transverse to their depth and maintained open by the geometrical form of those folds.
The resultant shape is not easy to visualise, but an illustrative model can be easily made in the following manner. Take a rectangular sheet of paper and fold it in half with a light fold parallel to one edge. Now fold the double sheet in zig-zag fashion at right angles to the first fold to form a number of pleats or corrugations. Pull the free edge of the apex of each corrugated half sheet away from its complementary edge by a short distance (say A"), and, maintaining this relationship, impress theresultant modification of fold firmly onto the first made lightfold. This fold will now be found to be modified from a straight line to a zig-zag line, and if the folded sheet is extended concertina-fashion along an axis parallel to the original light fold it will be found that the corrugated free edges are maintained effectively apart. The original light fold is representative of one of the fin edges of an element and the folds at right angles thereto are representative of the stiflt'ening corrugations.
The invention is illustrated in the accompanying drawings of a filter element section and a blank from which it may be folded. In the drawings:
Fig. 1 is a perspective view of a part of an element. Fig. 2 is a plan of a blank from which a part of an element such as shown in Fig. v1 can be folded.
Considering first Fig. l and assuming the right hand side of the drawing to represent the fluid inlet side it will be seen that the element presents to the flow folded edges 2,4, 6 and 8 and a plain edge 10, while the exit side of the element presents a plain edge l'and folded edges 3, 5, 7 and 9. There are, in effect four complete pleats. All of the pleats are formed substantially at right angles to their folds with a zig-zag or corrugated forma-' tion by the impression therein offolds having apices or lines of fold A, B, C, D, E, F, G, H and J.' These folds not only add strength to the pleated element but keep the pleats apart owing to their geometry. Fig. 2 shows Likewise the lines A, B I represent the lines ofzig-zag folding A, B J in Fig. 1.
The fold lines on Fig. 2 are designated Up or Down as the case may be to indicate that the adjacent surfaces are bent upwards or downwards.
Bending the sheet of Fig. 2 in the senses indicated will produce the element of Fig. 1.
The depth and pitch of the corrugations running across the length of the fins can be varied, depending upon the initial rigidity of the filter medium employed; for lower rigidity of filter medium the depth and pitch of the corrugations is reduced to obtain the required stilfness.
It may not generally be possible to fold the full number of fins required to form the filter element in one operation, due to the fact that when applying the corrugations cracking of the filter medium may occur when a number of layers are corrugated in the same operation. Under such circumstances, single sheets or three or four fins, dependent upon the nature of the filter medium, can be corrugated at a time, and having impressed the crease lines, the material may then be opened out. Having corrugated sufiicient sheets or sections to form the complete filter element, the leading and/or trailing edges of adjacent sections are then glued together in jigged relationship by .an adhesive. The edges of the sheets or sections may be coated with a pressure adhesive substance to facilitate this operation. Having performed the sticking operation the element can then readily be closed in on the width and the corrugations throughout the length of the fin will again take shape.
A variety of methods of sealing the filter element into its final housing may be devised, but the cheapest method is to use adhesive to stick the sides of the fins to the walls of the filter housing. Alternatively the Walls of the filter housing may be constructed to have adjacent to them the required number of tapered fingers attached only at one edge of the filter housing. The paper element can then be inserted into the housing in such a way that a tapered finger is situated between each corrugated tin of the element, thus retaining the folded edges of the fins in close contact with the wall of the housing. Dependent upon the rigidity of the medium used it may or may not be necessary to support the fins along the leading and trailing edges at intervals across the width of the element.
little way into the depth of the cavity between the fins, I
can be employed.
I claim:
1. A filter element comprised by a sheet of permeable" filter material, said' sheet being folded in zigzag fashion along one series of parallel straight lines and being folded in zigzag fashion along. another series of alternately inclined straight lines substantially but not precisely at right angles to the said first series of lines, the aberration" from rectangularity being such as to maintain pleats formed by said first folding apart from one another at minor acute angles.
2'. The method of forming a'pleated filter element, comprising folding at least one sheet of filtering medium upon itself in alternately directed folds in zigzag fashion along a first series of straight parallel lines to form first pleats, folding the pleated sheet upon itself in similar zigzag fashion along a second series of straight parallel lines substantially at right angles to said first series of lines to form a plurality of second pleats in each of said first pleats with the secondpleats in interleaved relation,
expanding the folded sheet to dispose said first pleats at minor acute angles relative to each other, and modifying the folds coincident With said first series of straight parallel lines to extend along alternately inclined straight lines generally but not precisely at right angles to said second series of lines, whereby the first pleats are strengthened by folds transverse their depth and main tained Open at minor acute angles by the geometrical form of those folds.
References Cited in the file of this patent UNITED STATES PATENTS
US503953A 1954-04-21 1955-04-26 Filter elements Expired - Lifetime US2862624A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB11554/54A GB764702A (en) 1954-04-21 1954-04-21 Improvements in filter elements
US503953A US2862624A (en) 1954-04-21 1955-04-26 Filter elements

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Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1163293B (en) * 1959-12-23 1964-02-20 Mine Safety Appliances Co Method of manufacturing a zigzag filter element
DE1202762B (en) * 1959-04-27 1965-10-14 Mine Safety Appliances Co Process for the production of a filter insert with filter layers running in a zigzag shape
US3433692A (en) * 1961-08-09 1969-03-18 Marc Wood Materials Sa Pour La Method for forming herringbone configurations for sandwich structures
US5458374A (en) * 1993-03-26 1995-10-17 Vijuk; Robert Universal non-jamming multi-ply multi-fold outsert with compact peripheral edges (and related method)
US5813700A (en) * 1993-03-26 1998-09-29 Vijuk; Joseph M. Methods of folding outserts
US6273411B1 (en) 1999-06-07 2001-08-14 Vijuk Equipment, Inc. Booklet forming method and apparatus
US6506275B1 (en) 2000-05-26 2003-01-14 Vijuk Equipment, Inc. Informational item forming and bonding machine and method
US6645134B2 (en) 2001-09-12 2003-11-11 Vijuk Equipment, Inc. Outsert-forming apparatus
US6656103B1 (en) 2000-11-28 2003-12-02 Vijuk Equipment, Inc. Informational item forming machine and method
US6709374B2 (en) 2002-01-18 2004-03-23 Vijuk Equipment, Inc. Booklet-forming machine and method
US6808480B2 (en) 2001-09-12 2004-10-26 Vijuk Equipment, Inc. Outsert-forming apparatus with glue verification
US20060211560A1 (en) * 2005-03-21 2006-09-21 Roger Mattila Methods of forming outserts
US20080283476A1 (en) * 2007-05-14 2008-11-20 Global Finishing L.L.C. Fluid filter and filtering method
EP2042359A1 (en) * 2007-09-28 2009-04-01 Valeo Systemes Thermiques Filter device and motor-vehicle air-conditioning system which employs the same
EP2240255A2 (en) * 2007-12-21 2010-10-20 3M Innovative Properties Company Joined filter media pleat packs
US10105632B2 (en) 2014-04-09 2018-10-23 Donaldson Company, Inc. Self-supporting folded sheet material, filter elements, and methods
US10112130B2 (en) 2012-10-09 2018-10-30 Donaldson Company, Inc. Self-supporting folded sheet material, filter elements, and methods
US10363766B2 (en) 2013-03-15 2019-07-30 G&K-Vijuk Intern. Corp. Information item forming machine with visual inspection unit and method for forming and sorting informational items
US11224833B2 (en) 2019-03-27 2022-01-18 Donaldson Company, Inc. Particle separator filter with an axially extending flow face
US11364462B2 (en) 2018-09-25 2022-06-21 Donaldson Company, Inc. Filter assembly

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2556521A (en) * 1946-11-14 1951-06-12 Fram Corp Filter element
US2683537A (en) * 1949-06-11 1954-07-13 Fram Corp Pleated filter element
FR1094978A (en) * 1953-11-28 1955-05-25 Filter cartridge for liquids or gases and processes for its constitution

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2556521A (en) * 1946-11-14 1951-06-12 Fram Corp Filter element
US2683537A (en) * 1949-06-11 1954-07-13 Fram Corp Pleated filter element
FR1094978A (en) * 1953-11-28 1955-05-25 Filter cartridge for liquids or gases and processes for its constitution

Cited By (62)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1202762B (en) * 1959-04-27 1965-10-14 Mine Safety Appliances Co Process for the production of a filter insert with filter layers running in a zigzag shape
DE1163293B (en) * 1959-12-23 1964-02-20 Mine Safety Appliances Co Method of manufacturing a zigzag filter element
US3433692A (en) * 1961-08-09 1969-03-18 Marc Wood Materials Sa Pour La Method for forming herringbone configurations for sandwich structures
US6158778A (en) * 1993-03-26 2000-12-12 Joseph M. Vijuk Methods of folding outserts
US5458374A (en) * 1993-03-26 1995-10-17 Vijuk; Robert Universal non-jamming multi-ply multi-fold outsert with compact peripheral edges (and related method)
US5813700A (en) * 1993-03-26 1998-09-29 Vijuk; Joseph M. Methods of folding outserts
US5909899A (en) * 1993-03-26 1999-06-08 Vijuk; Joseph M. Methods of folding outserts
US6068300A (en) * 1993-03-26 2000-05-30 Joseph M. Vijuk Methods of forming printed informational items
US6902197B2 (en) 1993-03-26 2005-06-07 Joseph M. Vijuk Methods of forming informational items
US6349973B1 (en) 1993-03-26 2002-02-26 Joseph M. Vijuk Methods of folding outserts
US20040033876A1 (en) * 1993-03-26 2004-02-19 Vijuk Joseph M. Methods of forming informational items
US6669235B2 (en) 1993-03-26 2003-12-30 Joseph M. Vijuk Methods of forming informational items
US6752429B2 (en) 1993-03-26 2004-06-22 Joseph M. Vijuk Methods of forming informational items
US6964413B2 (en) 1999-06-07 2005-11-15 Vijuk Equipment, Inc. Booklet forming method and apparatus
US6273411B1 (en) 1999-06-07 2001-08-14 Vijuk Equipment, Inc. Booklet forming method and apparatus
US20040256781A1 (en) * 1999-06-07 2004-12-23 Vijuk Joseph M. Booklet forming method and apparatus
US20030037884A1 (en) * 2000-05-26 2003-02-27 Vijuk Joseph M. Informational item bonding machine
US6506275B1 (en) 2000-05-26 2003-01-14 Vijuk Equipment, Inc. Informational item forming and bonding machine and method
US6837290B2 (en) 2000-05-26 2005-01-04 Vijuk Equipment, Inc. Informational item bonding machine
US7396322B2 (en) 2000-11-28 2008-07-08 Vijuk Equipment, Inc. Informational item forming machine and method
US6793614B2 (en) 2000-11-28 2004-09-21 William C. Neubauer Outsert-forming machine and method
US8485558B2 (en) 2000-11-28 2013-07-16 G&K-Vijuk Intern. Corp. Informational item forming method
US9592990B2 (en) 2000-11-28 2017-03-14 G&K-Vijuk Intern. Corp. Informational item forming method
US9624065B2 (en) 2000-11-28 2017-04-18 G&K-Vijuk Intern. Corp. Informational item forming method
US20060063656A1 (en) * 2000-11-28 2006-03-23 Neubauer William C Informational item forming machine and method
US20050037907A1 (en) * 2000-11-28 2005-02-17 Neubauer William C. Modular folding and pressing apparatus
US20050043162A1 (en) * 2000-11-28 2005-02-24 Neubauer William C. Informational item final folding apparatus
US20050043160A1 (en) * 2000-11-28 2005-02-24 Neubauer William C. Booklet forming method and apparatus
US20050096204A1 (en) * 2000-11-28 2005-05-05 Neubauer William C. Outsert-forming method
US20040038797A1 (en) * 2000-11-28 2004-02-26 Neubauer William C. Informational item forming machine and method
US6656103B1 (en) 2000-11-28 2003-12-02 Vijuk Equipment, Inc. Informational item forming machine and method
US9624064B2 (en) 2000-11-28 2017-04-18 G&K-Vijuk Intern. Corp. Informational item forming method
US8029430B2 (en) 2000-11-28 2011-10-04 Vijuk Equipment, Inc. Outsert-forming method
US7121992B2 (en) 2000-11-28 2006-10-17 Vijuk Equipment, Inc. Informational item forming machine and method
US20100069214A1 (en) * 2000-11-28 2010-03-18 Vijuk Equipment, Inc. Outsert-Forming Method
US7182723B2 (en) 2000-11-28 2007-02-27 Vijuk Equipment, Inc. Informational item final folding apparatus
US7621862B2 (en) 2000-11-28 2009-11-24 Vijuk Equipment, Inc. Outsert-forming method
US7247129B2 (en) 2000-11-28 2007-07-24 Neubauer William C Outsert-forming method
US7476193B2 (en) 2000-11-28 2009-01-13 Vijuk Equipment, Inc. Modular folding and pressing apparatus
US20070281846A1 (en) * 2000-11-28 2007-12-06 Vijuk Equipment, Inc. Outsert-Forming Method
US6645134B2 (en) 2001-09-12 2003-11-11 Vijuk Equipment, Inc. Outsert-forming apparatus
US6808480B2 (en) 2001-09-12 2004-10-26 Vijuk Equipment, Inc. Outsert-forming apparatus with glue verification
US6852072B2 (en) 2002-01-18 2005-02-08 Vijuk Equipment, Inc. Booklet-forming machine
US6709374B2 (en) 2002-01-18 2004-03-23 Vijuk Equipment, Inc. Booklet-forming machine and method
US20040162208A1 (en) * 2002-01-18 2004-08-19 Vijuk Equipment, Inc. Booklet-forming machine
US20060211560A1 (en) * 2005-03-21 2006-09-21 Roger Mattila Methods of forming outserts
US20070126228A1 (en) * 2005-03-21 2007-06-07 Vijuk Equipment, Inc. Methods of Forming Outserts and Outserts Formed Thereby
US7175586B2 (en) 2005-03-21 2007-02-13 Vijuk Equipment, Inc. Methods of forming outserts
US7896796B2 (en) 2005-03-21 2011-03-01 Vijuk Equipment, Inc. Methods of forming outserts and outserts formed thereby
US7771517B2 (en) * 2007-05-14 2010-08-10 Global Finishing Solutions, L.L.C. Filtering method
US20080283476A1 (en) * 2007-05-14 2008-11-20 Global Finishing L.L.C. Fluid filter and filtering method
JP2009083668A (en) * 2007-09-28 2009-04-23 Valeo Thermal Systems Japan Corp Filter device and motor-vehicle air-conditioner using the same
EP2042359A1 (en) * 2007-09-28 2009-04-01 Valeo Systemes Thermiques Filter device and motor-vehicle air-conditioning system which employs the same
EP2240255A4 (en) * 2007-12-21 2011-05-04 3M Innovative Properties Co Joined filter media pleat packs
US20100269463A1 (en) * 2007-12-21 2010-10-28 Duffy Dean R Joined filter media pleat packs
US8491689B2 (en) 2007-12-21 2013-07-23 3M Innovative Properties Company Joined filter media pleat packs
EP2240255A2 (en) * 2007-12-21 2010-10-20 3M Innovative Properties Company Joined filter media pleat packs
US10112130B2 (en) 2012-10-09 2018-10-30 Donaldson Company, Inc. Self-supporting folded sheet material, filter elements, and methods
US10363766B2 (en) 2013-03-15 2019-07-30 G&K-Vijuk Intern. Corp. Information item forming machine with visual inspection unit and method for forming and sorting informational items
US10105632B2 (en) 2014-04-09 2018-10-23 Donaldson Company, Inc. Self-supporting folded sheet material, filter elements, and methods
US11364462B2 (en) 2018-09-25 2022-06-21 Donaldson Company, Inc. Filter assembly
US11224833B2 (en) 2019-03-27 2022-01-18 Donaldson Company, Inc. Particle separator filter with an axially extending flow face

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