CA1105665A - Method and apparatus for forming a material web - Google Patents

Method and apparatus for forming a material web

Info

Publication number
CA1105665A
CA1105665A CA299,679A CA299679A CA1105665A CA 1105665 A CA1105665 A CA 1105665A CA 299679 A CA299679 A CA 299679A CA 1105665 A CA1105665 A CA 1105665A
Authority
CA
Canada
Prior art keywords
particulate material
flow
distribution chamber
chamber
composite flow
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
Application number
CA299,679A
Other languages
French (fr)
Inventor
Lennart Gustavsson
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.)
Svenska Flaktfabriken AB
Original Assignee
Svenska Flaktfabriken AB
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 Svenska Flaktfabriken AB filed Critical Svenska Flaktfabriken AB
Application granted granted Critical
Publication of CA1105665A publication Critical patent/CA1105665A/en
Expired legal-status Critical Current

Links

Classifications

    • DTEXTILES; PAPER
    • D04BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
    • D04HMAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
    • D04H1/00Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
    • D04H1/70Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres
    • D04H1/72Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged
    • D04H1/732Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged by fluid current, e.g. air-lay
    • DTEXTILES; PAPER
    • D04BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
    • D04HMAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
    • D04H1/00Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
    • D04H1/70Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres
    • D04H1/72Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged
    • DTEXTILES; PAPER
    • D04BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
    • D04HMAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
    • D04H1/00Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
    • D04H1/70Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres
    • D04H1/72Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged
    • D04H1/736Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged characterised by the apparatus for arranging fibres

Landscapes

  • Engineering & Computer Science (AREA)
  • Textile Engineering (AREA)
  • Preliminary Treatment Of Fibers (AREA)
  • Dry Formation Of Fiberboard And The Like (AREA)
  • Nonwoven Fabrics (AREA)
  • Paper (AREA)
  • Forging (AREA)
  • Developing Agents For Electrophotography (AREA)
  • Dowels (AREA)

Abstract

METHOD AND APPARATUS FOR FORMING A WEB OF MATERIAL
Lennart Gustavsson ABSTRACT OF THE DISCLOSURE

A web is formed from particulate material, for example, wood fibers, by depositing the fibers on a conveyor surface in a distribution chamber. The particulate material is introduced into the distribution chamber at its top by a carrier air stream which is caused to oscillate across the surface by impulses from separate control blow boxes on the opposite sides of the stream. The particulate material is thoroughly dispersed in the air stream by passage through a transition zone where the carrier air stream is deflected into a zigzag path and its flow velocity is reduced. The effect of static electricity on the particles in the carrier stream is reduced by lining the transition zone with nonconductive material and providing ionizing devices in the blow boxes for the air flow passing through the control boxes, or in the chamber adjacent the boxes.

Description

The present invention relates to a method and apparatus for forming a web and constitutes an improvement on the apparatus shown in my c~-pending Canadian patent application Serial No.
261,048, filed September 13, 1976.
As shown in my prior patent, a web is formed on a conveyDr by carrying particulate materia~ into a distribution chamber by means of a carrier air stream. The air stream is oscillated across-thP-width ~f the,chamber by,imp~lses_fro~
cDntrol jets t~ form a web on the conveyor surface which has 10 ' proved very efficient with a gDod yield with respect to uni- ;~
formity and quality in ~eneral. In certain installations, however, problems have arisen when the composite stream of materials supplied to the distribution chamber!is discharged with sufficient speed to fonm streaks, resulting in irregularities ~' in the web formed. Furthermor'e, static electricity generated by wood particles, in particular particles which have a mois-ture content of ~elow 1~%, causes irregularities in the forming process since the charged particles may deposit on the walLs of the chamber and are droppè'd'randomly,in cl~ps. Under severe conditions the electrostatic charge may `be sufficient to cause sparking. The present invention provides means fGr eliminating these prDblems and thereby enhances the uniformity and quality ,~ , of the web material formed, regardless '~f the problems caused by the materials discussed abDve.
Specifically, the present invention provides a transi-tion zone for the composite flow of carrier air and the particu-late material in ad~ nce of its entry into the distributiDn chamber ,,~, to assure unifor,m dispersiDn of the particulate material through the carrier ~ir stream,and the invention also reduces the static electricity on the particles in the distribution chamber.
All of the objects of the invention are m~re fully setforth hereinafter with reference to the accompanying drawings, wherein:

,. . .
., .. , ., ~

~56!65 Fig. 1 is a lDngitUdinal sectiOn thrDug h a transitiDn ., zone of the web ~rming apparatus;
Fig. 2 is a cross section of the transition zone;
Fig~ 3 illustrates the positioning of ionizing rods disposed in the distribution chamber;
Fig. 4 illustrates ionizing rods mounted in the blow boxes;
Fig. 5 is a perspective view of web forming apparatus embcdying the present invention; and lOFig. 6 is a transve-se section through the distributiDn chamber.
With reference to Fig. 5, the apparatus of the present invention provides a distribution chamber 1 which is open at its bottom to accoL~nodate a running conveyor belt S which forms the deposition surface of the web forming apparatus. At the top of the chamber l,blow boxes 11 and 12 are provided on opposite sides of an inlet nozzle 3 which is connected to a supply conduit 2 through a transition zone 90 (also referred to as a transition c~lamber) having a zigzag-shaped passageway 9l which forms a preferred emYx~DInt of dispersion means. As indicatedin Fig.6 the composite flow fromthepassageway 9l is introduced into cha~ber l through the nozzle 3 ;and is caused to oscillate across the width of the chamber by me~s of impulse jets fr~m ~e flow boxes ll and 12, as described in detail in the prior patent.
In accordance with the present invention, the transition zone 90 provides a th~rough dispersion of the particulate material throughout the carrier air flow. To this end, the crDss section of the transition zone diverges in the direction of the fiber flow and the longitudinal direction of the web bein~ formed.
As further appearS from Figs. 2 and 5, the transition zone 90 provides a zig~ag passag~ ay which thereby deflects the carrier air stream and with the particles therein several times throughout its passave through the transition zone 90. Each de1ection ~f the cDmposite ~LW generates a resistance which is balanced ., 566S ~

with the change in dynamic pressure resulting from the reduction of air velDcity caused by the expanding cross section of the passageway. The combination of the reducing air speed and the deflecting walls of the passageway assures against limited zones of excess speed which m~t cause streaks. Thus, the composite gas/particle stream has a unifonm speed profile as it leaves=the nozzle 3 and flows-into:the distribution~chamber 1.
During the passage of the composite flGw thrDugh thé transition zone, the velocity of the flow is reduced, fGr exampLey from 25 meters per second to L0 meters per second. Preferably the velocity of the composite flow is reduced to at least one half its initial velocity~
In accordance with another feature of the invention, the transition passageway 91 ~s lined with wood material 92, preferably plywood, wood fiberboard or the like,whereby an efficient reduction of the static eLectricity of the particles or fibers is obtained. As an example~ it may be mentioned that tests have proved that the use of this device results in a reduction in electric field strength from to 200,0~ V/m tD about 30,000 V/m. The invention is not limited to this particle configuration of transition zone, but other fonms are possible.
For example, the transition zone may be located remote from the distribution chamber in the distribution conduit 2.
In Figs. 3 and 4, embodiments of blow boxes 11 and 12 are shown in detail. As shown in Fig. 3, ionizing rods 93 are disposed in ~he distribution chamber adjacent the blow boxes in order to further reduce sta~ic electricity. The ionizing r rods are connected to an al~ernating-current source (not shown) to provide an electric voltage which ionizes the ambient gas and thereby reduces any static electricity remaining with the fibers of the composite flow issuing from the no~zle 3~ Preferably the applied voltage is in an alternating-current voltage in the range of 3-20 kv. In Figo 4, ionizing rods 94 are disposed with-i6~5 in the blow boxes 11 and 12 for ionizing the f1DW which generates the impulse jets for controlling the oscillation of the composite flow through the distribution chamber 1. By this arrangement, the impulse jets are ionized and are efficiently mixed into the composite stream The ionizing rods, being disposed in the blow box, are protected against mechanical damage and are also protected against dust loading.~ Furth rmore, the shielding of the rDds within the blow box insures against c-ontac~t~with the ~ --personnel servicing installation.
While particular embodiments of the present invention have been herein illustrated and described, it it apparent that the invention is not limited to the particular embodiments illustrated but the features may be combined and modified, all within the scope of the following claims.

A ~ ;
;

Claims (19)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:
1. In a method of forming a material web com-prising the steps of causing a composite flow of particulate material in a gaseous carrier to flow into a distribution chamber, depositing particulate material from said flow on a carrier surface in the chamber to form a web of the particulate material on said surface, exposing the composite material flow in said distribution chamber to control flows of gaseous medium directed from opposite sides of the com-posite flow to cause the composite flow to oscillate across the width of the carrier surface and to distribute the particulate material across the same, the improvement comprising the additional steps of passing the composite flow of particulate material in the gaseous carrier through a transition zone piror to exposing the flow to control flows in said distribution chamber, and deflecting the composite flow several times throughout its passage through said transition zone whereby the particulate material is dispersed uniformly throughout the gaseous carrier.
2. A method according to claim 1 wherein the transition zone subjects the composite flow to zigzag deflection movements and to an expanding cross sectional passage area in the direction of the travel of the flow toward the carrier surface.
3. A method according to claim 2 wherein the expanded flow area in said transition zone reduces the velocity of the carrier flow to at least one half its initial velocity prior to its flow into said distribution chamber.
4. A method according to claim 1 wherein said particulate material generates static electricity therein, and including the step of passing the composite flow in the transition zone between static-reducing material for reducing the static electricity of the particulate material.
5. A method according to claim 4 wherein said static-reducing material is composed of wood.
6. A method according to claim 1 wherein said particulate material generates static electricity therein, and including the step of reducing the static electricity of the particulate material by exposing the particulate material to ionized gas.
7. A method according to claim 1 including the steps of reducing the static electricity of the particulate material in said composite flow by exposing the particulate material in the distribution chamber to ionized gas, and supplying the ionized gas to said chamber by ionizing the gaseous control medium in the control flows prior to directing them against the composite flow in the chamber.
8. A method according to claim 7 including the step of ionizing the control medium by ionizing rods.
9. A method according to claim 1, including the steps of reducing the static electricity of the particulate material in said composite flow by exposing the particulate material in the distribution chamber to ionized gas, and producing the ionized gas in the distribution chamber by ionizing the composite flow within said chamber after exposure to said control flows while it flows toward the carrier surface.
10. A method according to claim 7 or claim 9 including the step of producing the ionized gas by ionizing rods supplied with an electric alternating-current voltage between 3 and 20 kV.
11. Apparatus for forming a web of particulate material comprising a distribution chamber, a carrier surface provided therein, a nozzle opening within the distribution chamber for supplying a composite flow of particulate material distributed in a carrier gaseous medium, and control gas flow means for supplying control gas streams to opposite sides of said composite flow to impart a variable impulse to cause said composite flow to be distributed across the full width of the distribution chamber and of the carrier surface therein, the improvement wherein a transition chamber for passage of the composite flow is provided upstream of said nozzle, said transition chamber being provided with dispersion means for generally uniform dispersion of the particulate material throughout the carrier gaseous medium.
12. Apparatus according to claim 11 wherein the dispersion means is formed by a zigzag passageway which gradually increases in cross sectional area at cross-sections generally parallel with the carrier surface in the direction of passage of said composite flow through said transition chamber
13. Apparatus according to claim 12, wherein the carrier surface is movable in a predetermined direction, the increase in cross-sectional area being effected by gradual increase in the distance between mutually opposite end walls of the passageway, as measured in the direction of movement of said carrier surface.
14. Apparatus according to claim 13 wherein walls forming the passageway are made of material reducing the charge of static electricity occurring on the particles.
15. Apparatus according to claim 14 wherein said material reducing the charge is wood.
16. Apparatus according to claim 11, further comprising ionizing rods mounted in the path of at least one of said gas streams for reducing static electricity of the particles in the distribution chamber.
17. Apparatus according to claim 16 wherein said control gas stream means comprises blow boxes at mutually opposite sides of said composite flow path for producing im-pulse jets, said ionizing rods being disposed within said blow boxes.
18. Apparatus according to claim 16 wherein said ionizing rods are disposed within said distribution chamber in the path of the composite flow.
19. A device according to claim 16 wherein said ionizing rods are supplied with an alternating-current voltage source in the range of 3-20 kV.
CA299,679A 1977-03-25 1978-03-23 Method and apparatus for forming a material web Expired CA1105665A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE7703460-1 1977-03-25
SE7703460A SE403585B (en) 1977-03-25 1977-03-25 METHODS AND DEVICES FOR FORMING A MATERIAL PATH BY DEPOSITING IN A DISTRIBUTION CHAMBER INTRODUCING IN GASY MEDIUM DISTRIBUTED STREAM OF PARTICLES, EXV FIBERS, ON A DISTRIBUTION CHAMBER ARRANGED

Publications (1)

Publication Number Publication Date
CA1105665A true CA1105665A (en) 1981-07-28

Family

ID=20330842

Family Applications (1)

Application Number Title Priority Date Filing Date
CA299,679A Expired CA1105665A (en) 1977-03-25 1978-03-23 Method and apparatus for forming a material web

Country Status (13)

Country Link
JP (1) JPS53143775A (en)
AU (1) AU517535B2 (en)
CA (1) CA1105665A (en)
DD (1) DD136370A6 (en)
DE (1) DE2812381A1 (en)
FI (2) FI62384C (en)
FR (1) FR2384615A2 (en)
NO (1) NO149537C (en)
PL (1) PL117170B3 (en)
RO (1) RO74099A (en)
SE (1) SE403585B (en)
SU (1) SU882418A3 (en)
YU (1) YU41091B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE450256B (en) * 1983-12-23 1987-06-15 Svenska Traeforskningsinst SET AND DEVICE FOR PREPARING LAYERS OF DRY FIBERS ON A FORM

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3777231A (en) * 1972-09-27 1973-12-04 A Guschin A device for forming a layer of fibrous material of homogeneous structure
GB1550167A (en) * 1975-05-09 1979-08-08 Owens Corning Fiberglass Corp Method and apparatus for producing fibrous packs
SE397943B (en) * 1975-09-26 1977-11-28 Svenska Flaektfabriken Ab METHODS AND DEVICES FOR FORMING A MATERIAL PATH BY DEPOSITING IN A DISTRIBUTION CHAMBER INTRODUCING INTO GASY MEDIUM DISTRIBUTED STREAM OF PARTICLES, FOR EXAMPLE FIBERS, ON A DISTRIBUTION CHAMBER ...

Also Published As

Publication number Publication date
FI62385B (en) 1982-08-31
FR2384615A2 (en) 1978-10-20
NO781028L (en) 1978-09-26
YU69678A (en) 1982-10-31
SU882418A3 (en) 1981-11-15
NO149537B (en) 1984-01-30
DD136370A6 (en) 1979-07-04
JPS6120650B2 (en) 1986-05-23
FI62384B (en) 1982-08-31
AU3368378A (en) 1979-09-06
DE2812381C2 (en) 1989-04-27
FR2384615B2 (en) 1982-01-08
DE2812381A1 (en) 1978-09-28
FI62385C (en) 1982-12-10
FI62384C (en) 1982-12-10
AU517535B2 (en) 1981-08-06
NO149537C (en) 1984-05-09
JPS53143775A (en) 1978-12-14
PL205462A1 (en) 1978-11-06
FI780904A (en) 1978-09-26
SE403585B (en) 1978-08-28
RO74099A (en) 1981-02-28
YU41091B (en) 1986-12-31
PL117170B3 (en) 1981-07-31
FI780905A (en) 1978-09-26

Similar Documents

Publication Publication Date Title
US4269578A (en) Apparatus for forming a web of material
CA2121383C (en) Apparatus for producing a nonwoven spun-filament web of aerodynamically stretched filament of a plastic
US5766646A (en) Apparatus for making a fleece from continuous thermoplastic filaments
US6966762B1 (en) Device for opening and distributing a bundle of filaments when producing a nonwoven textile web
JPH07505687A (en) Thermoplastic filament web manufacturing device and manufacturing method
CA2203137A1 (en) Method and apparatus for forming a pulsed stream of particles for application to a fibrous web
JP2006057233A (en) Mechanism for continuously producing nonwoven fabric web comprising thermoplastic synthetic resin filament
EP1432861B2 (en) Apparatus and method for producing a nonwoven web of filaments
DK161343B (en) PROCEDURE FOR THE PREPARATION OF A MATERIAL COURT AND PLACES FOR EXERCISING THE PROCEDURE
US3296678A (en) Method and apparatus for producing nonwoven webs
CA1137266A (en) System and method for dispersing filaments
WO1981002172A1 (en) System and method for dispersing filaments
US3881653A (en) Powder deposition system
CA1105665A (en) Method and apparatus for forming a material web
GB1597577A (en) Apparatus for the surface treatment of galvanized steel strip
US4197267A (en) Method for forming a web of material
KR0148269B1 (en) Gas management system for closely-spaced laydown jets
US4035870A (en) Fiber distribution and depositing apparatus
US3698610A (en) Process and device for the manufacture of a non-woven matted web from synthetic yarn
JPS6320188B2 (en)
US20040011471A1 (en) Installation for producing a spunbonded fabric web whereof the diffuser in distant form the drawing slot device
US3681169A (en) Apparatus for the continuous manufacture of wicks,threads and screens from thermoplastic materials
US4601741A (en) Method and apparatus for producing a continuous glass filament mat
US2730460A (en) Electrostatic method and apparatus
US4600423A (en) Method and apparatus for producing a continuous glass filament mat

Legal Events

Date Code Title Description
MKEX Expiry