US3381069A - Method for producing a fibrous mat - Google Patents

Method for producing a fibrous mat Download PDF

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Publication number
US3381069A
US3381069A US472100A US47210065A US3381069A US 3381069 A US3381069 A US 3381069A US 472100 A US472100 A US 472100A US 47210065 A US47210065 A US 47210065A US 3381069 A US3381069 A US 3381069A
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United States
Prior art keywords
fibers
air
binder
stream
mat
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
US472100A
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English (en)
Inventor
Allen L Simison
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.)
Owens Corning
Original Assignee
Owens Corning Fiberglas Corp
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 NL131118D priority Critical patent/NL131118C/xx
Application filed by Owens Corning Fiberglas Corp filed Critical Owens Corning Fiberglas Corp
Priority to US472100A priority patent/US3381069A/en
Priority to FR69036A priority patent/FR1486364A/fr
Priority to BE683958D priority patent/BE683958A/xx
Priority to DE1635572A priority patent/DE1635572C3/de
Priority to NL6609795A priority patent/NL6609795A/xx
Priority to LU51552D priority patent/LU51552A1/xx
Priority to SE09660/66A priority patent/SE332137B/xx
Priority to GB31699/66A priority patent/GB1141815A/en
Priority to US708462A priority patent/US3544414A/en
Application granted granted Critical
Publication of US3381069A publication Critical patent/US3381069A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • 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
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29BPREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
    • B29B15/00Pretreatment of the material to be shaped, not covered by groups B29B7/00 - B29B13/00
    • B29B15/08Pretreatment of the material to be shaped, not covered by groups B29B7/00 - B29B13/00 of reinforcements or fillers
    • B29B15/10Coating or impregnating independently of the moulding or shaping step
    • B29B15/12Coating or impregnating independently of the moulding or shaping step of reinforcements of indefinite length
    • 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

Definitions

  • ABSTRACT OF THE DISCLOSURE A method for making a fibrous mat from Waste gatherings of fibers which are horizontally discharged from a toothed cylinder and joined with a merging air stream mixing with the fibers to carry them through a horizontal guiding spout.
  • a binder suspension is sprayed from above and below on the emerging stream of air and fibers which pass to a foraminous receiving surface having suction means therein to draw the fibers and binder into a composite mat.
  • This invention relates to a method for producing a fibrous mat. Vfhile the invention is particularly concerned with the production of relatively thick bonded mats of fibrous glass, it is also applicable to forming thin felted structures and mats composed of other fibers both natural and synthetic, or a combination of various fibers.
  • An outstanding characteristic which this invention contributes to the products thereof is thorough and uniform integration, derived from the fine and eifective distribution of the binder particles through the body of fibers.
  • This feature is of high value in many forms of blankets and boards for heat and sound insulation, cushioning, padding and fil ering.
  • the range of specific uses for the products include roofing insulation; duct lining; insulating automobiles, trucks, trailers, and railroad cars; mattresses; and blanketing of concrete during curing.
  • the practice of the invention has been found highly useful in producing bonded mats from a blend of reprocessed fibrous glass including strands originally intended for textile processing and trimmings and rejected material from various fibrous glass mat forming operations.
  • the main object of this invention is to provide a method for producing an improved bonded fibrous mat.
  • a further object is a method for refiberizing fibrous bodies and forming a mat therefrom, and economically and etliciently dispersing binder particles among the fibers of the mat.
  • an object of the invention is to produce an airborne stream of fibers from fibrous material and to introduce into the stream of fibers finely atomized airborne binder particles in a liquid carrier.
  • Another object of the invention is to form a wide, smooth surfaced, fibrous mat of uniform thickness and density.
  • a still further object is to efiectively and uniformly combine a mixture of different fibrous components in a fibrous mat after first fiberizing such components.
  • the fibrous glass strands are removed from the cylindrical holders on which they are originally packaged for textile use by splitting the body of strands with a knife.
  • the bulk strands are then fed through a chopper and cut to an average length of one and one half inches. If the water size ordinarily applied to textile strands has not dried, heat is then applied to the chopped strands.
  • the chopped strands are subsequently delivered at a weight controlled rate to a raw material conveyor by a picker feeder.
  • a similar picker feeder adds a weight controlled proportion of the admix of waste fibrous glass mat material to the cut strands on the conveyor.
  • the mat material may in one instance constitute thirty percent of the full batch.
  • the combined components are mixed and further shredded by being passed through a picker from which the batch is delivered through an air duct to the feeder of a garnett machine.
  • the toothed cylinders and worker rolls of this machine separate, straighten and arrange the fibers uniformly in a loose progressing web.
  • This web is disintegrated in being discharged through a guiding spout from the garnett machine in an air stream and the fibers are airborne as a spreading cloud.
  • the fibers with the binder particles intermixed therewith fall within the chamber through gravitation and as influenced by a downward air draft drawn down through the foraminous conveyor, and settle on the conveyor which is traveling in line with the discharge path of the fibers.
  • the fibers with the binder particles precipitated thereon accumulate in a low density pack in a thickness depending upon various factors including the speed of the conveyor and which is generally established in a range between six and eight inches.
  • the pack is carried into a curing oven between conveyor flights which compress the pack to the thickness desired in the final mat product which is usually between one and three inches. With the pack so compressed the binder is cured to permanently establish the flexibility, thickness and density of the product.
  • the mat On leaving the oven the mat is cut lenghtwise into desired widths and the edges trimmed.
  • the action of a cross chopping knife determines the length of the iridividual mats which are then rolled up on a mandrel for storage, further processing or shipment.
  • FIGURE 1 of the drawings the outlet end of a garnett machine and the entering end of an associated forming hood are shown in side elevation;
  • FiGURE 2 is a plan view of the apparatus of FIG- URE 1;
  • FIGURE 3 is an enlarged side elevation largely in section of the fiber discharging portion of the garnett machine of FIGURES 1 and 2, as viewed from the opposite side thereof;
  • FIGURE 4 is a side elevation on a reduced scale of the outlet end of the garnett. machine and the main section of the forming hood;
  • FIGURE 5 is a planview of the apparatus of FIG- URE 4.
  • the outlet end of the garnett machine 11 is supported upon a base 10.
  • a low speed doffer cylinder 12 removes the web of worked fibers from the first main cylinder (not illustrated) of the garnett machine.
  • the garnettmachine here utilized forms a web six feet in width.
  • the small stripper roll 16 cooperates in the transfer of the web from the doifer cylinder 12 to the final high speed main cylinder 14, while a relatively slow worker roll 17 combs the fibers of the web before the web is propelled from the cylinder 14 into the path of the air air spouts 18.
  • the cylinder '14 is thirty inches in diameter and is driven at an r.p.m.
  • FIGURE 3 there is an open area 23 above a top portion of the cylinder 14 into which the web of fibers is thrust.
  • the web in disintegrated form then travels through the guiding spout 20.
  • the top wall 21 of the spout may be positioned to establish the desired height of the air channel therethrough.
  • a small two inch roller 24 is mounted adjacent thereto. This may be forcibly rotated as indicated by the arrow thereon at a speed for instance of 100 r.p.m. However, freely mounted it has been found to rotate under the action of the air stream thereover and to thus satisfactorily fulfill its function.
  • the guiding spout 20 is preferably composed of Lu-. cite, an acrylic plastic produced by the E. I. du Pont Company or of other electrical insulating material. Because of electrical charges apparently accumulated 0n the glass fibers during their travel through the garnett machine the fibers have been found to collect on metal walls of such a spout. The insulating character of Lucite overcomes this attraction and surfaces thereof remain clean of fibers.
  • the guiding spout 20 in the present embodiment is dimensioned to provide an air passage therethrough approximately two inches high, six feet wide and two feet long. The air in an estimated volume of forty five hundred cubic feet per minute flows through spout 20 at a velocity of forty five hundred feet per minute.
  • the air borne stream of fibers is directed into the expanding spout 27 which is also composed of Lucite for reduction of electrostatic attraction.
  • a con siderable volume of additional air is drawn therein from the spacing between the spouts.
  • Upper and lower louvers 29 and 30 at the outlet of the spout 27 are set to constrict and direct the air borne stream of fibers in a path found most effective in propelling the fibers into the forming hood 34.
  • the passage through the expanding spout 27 is six inches high, six and one half feet wide, and four feet long.
  • the larger cross sectional area of spout 27 permits the volume of air to be greatly expanded by induction with some decrease in the velocity of the air stream as projected from spout 20.
  • the binder through each nozzle is reduced to an amount that may be thoroughly and finely atomized.
  • this provides very uniform and effective dispersion of the binder particles among the fibers.
  • the fine atomization of the bindersolution results in the binder particles averaging only ten microns in diameter with very few reaching a diameter of one hundred microns.
  • a preferred binder composition is a ten percent phenol formaldehyde water solution with the resin in A state of polymerization. This may be introduced by the atomizing nozzles at a rate supplying a residual binder component of fifteen percent of the total weight of the final mat product. Under a comparatively high production schedule approximately six ounces of the water suspension of binder per minute is then atomized by each nozzle. However, more or less binder may be utilized according to the degree of stiifness and integrity desired in the final product. Many other binder materials of natural or synthetic origin may of course be utilized in place of the specific presently preferred resin.
  • the fine binder particles enter and spread through the flowing stream of air and fibers.
  • the high volume of air including that'directly from spout 27 and that induced into immediate joinder therewith adjacent the outlet of spout 27 probably exceeds twenty thousand cubic feet of air per minute.
  • Dispersed evenly through this mass of air, constituting approximately only one part by volume to three hundred thousand parts of air are the glass fibers, mostly as individual fibers in spaced relation, but also in small clumps rarely containing as many .as fifty fibers.
  • the dispersion however, of the fibers and tiny binder droplets in the air is so thorough that each cubic inch of air will usually contain about twenty five or more fibers and roughly two hundred droplets of binder.
  • the fibers 32 with the intermingled particles of binder are drawn down upon the nine foot wide conveyor 36 by gravity and the downward flow of air through the conveyor into the suction chamber 38.
  • Groups'of lateral air ducts 39, 49, 51 and 53 provide paths for air drawn from the chamber 38 by suitable air blowers into the common air plenum 54.
  • dampers 37 "in the air ducts the air suction may be varied along the chamber 38.
  • Air flow into the forming hood 34 is derived fromt'he air from spouts 18 greatly augmented by air projected from'the peripheral surface of cylinder 14, extra air induced into the second guiding spout 27, to a minor extent from the atomizing air from nozzles 40, andmajorly from air entering the open'face of the forming hood. Additional air moves into the forming'hood through openings 58 in the ceiling panel 59 of the forming hood and through openings 55 above side panels 56 of the hood.
  • top panels 60 and side panels 62 Further sections of the forming hood are closed by top panels 60 and side panels 62.
  • This added air while slowing and somewhat expanding the fiber movement helps bring the fibers and binder particles down upon the conveyor as such added air moves downwardly in response to the air suction.
  • This suction of air into the chamber 38 below the conveyor is at such negative pressure and in sufficient volume to rapidly draw the main mass of fibers down upon the first portion of the conveyor surface.
  • the closed sides of the hood along the borders of the fiber stream as well as the suction at the edges of the conveyor spreads the deposit of fibers and binder particles across the conveyor.
  • the air passes down through the screen conveyor which in effect thus filters the fibers from the air.
  • the fibers in turn serve as a filtering body for the binder particles intermingled therewith.
  • the thirty foot long forming hood 34 extends four feet above the surface of the conveyor 36 and is approximately as wide as the nine foot width of the conveyor.
  • the openings 57 and 58 in the fore part of the top of the forming hood are five feet long and three feet wide while the openings 55 above the side panels 56 are ten feet long and one foot Wide.
  • the top and sides of the hood are otherwise closed up to the discharge end of the hood.
  • the mat of fibers and binder particles is transported through a curing oven of conventional design.
  • the mat is there compressed to the desired thickness (unlikely to exceed three inches) and density (as high as ten pounds per cubic foot but usually below three pounds) between opposed flights of upper and lower conveyors while air heated to 350 F. is driven through the foraminous conveyor flights and the compressed mat to cure the binder particles and thus integrate and set the mat in the selected thickness and density.
  • the mat moves through edge trimmers, longitudinal slitters, and cross cutting devices to form units of desired widths and lengths.
  • a mat eight feet wide remains after the edge trimming operation and is slit in half to form four foot rolls wound on stocking mandrels.
  • the edge trimmings are salvaged and added to the raw material to be subsequently processed.
  • the final products have unusual integrity and homogeneous characteristics. While different proportions of the binder may be utilized depending upon the degree of strength and rigidity required, because of its original liquid nature and its even distribution a minimum amount is effective and is highly economical. This superior performance is especially valuable where a mixture of fibers of dilferent lengths and sizes is involved as in the processing with which this invention is particularly concerned.
  • the principal features which contribute to the success of this invention include the spout means for directing and expanding the high velocity air borne stream of fibers, the discharge of the fibers through an open area before they enter the forming hood, the projection of atomized liquid binder upon opposite sides of the planar stream of fibers in the open area, the metered supply of the binder to a high number of closely arranged nozzles, and the controlled air flow into the open face of the hood and through openings in the sides and top thereof down through the foraminous conveyor.
  • a method for producing a bonded fibrous mat which comprises separating and combing gatherings of fibers in a garnett-type machine, discharging the fibers horizontally and tangentially from the upper surface of a toothed cylinder of the machine, directing a stream of substantially unheated air over the upper surface of the cylinder into traveling association with the fibers, directing the combined stream of air and fibers through a fiat horizontal guiding spout, projecting binder particles in a liquid carrier into the upper and lower sides of the horizontal stream of air and fibers issuing from the spout, and drawing the fibers and binder particles by suction downwardly for deposit upon a receiving surface.
  • a method according to claim 1 in wr ich the binder particles are projected from upper and lower series of closely arrayed nozzles spaced on the average no more than five inches apart.
  • a method according to claim 1 in which an open faced hood is positioned in generally enclosing relation over the receiving surface, and the stream of air and fibers is directed through an open area before entering the hood and being deposited upon the receiving surface, whereby additional air is induced by the stream to flow along with it into the hood, and the binder particles are directed into the stream of air and fibers immediately before the stream enters the hood.
  • a method for producing a fibrous mat from gatherings of fibers which comprises combing and separating the fibers of such gatherings, propelling the fibers in a high velocity stream horizontally and tangentially from the upper surface of a toothed cylinder, directing a blast of substantially unheated air at a velocity lower than the velocity of said fiber stream over the upper surface of the cylinder into merging relation with the stream of fibers, directing fine particles of a liquid binder into the combined stream of air and fibers and drawing the combined stream of air, fibers and binder particles down upon a foraminous receiving surface.

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  • Engineering & Computer Science (AREA)
  • Textile Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Nonwoven Fabrics (AREA)
US472100A 1965-07-15 1965-07-15 Method for producing a fibrous mat Expired - Lifetime US3381069A (en)

Priority Applications (10)

Application Number Priority Date Filing Date Title
NL131118D NL131118C (pt) 1965-07-15
US472100A US3381069A (en) 1965-07-15 1965-07-15 Method for producing a fibrous mat
BE683958D BE683958A (pt) 1965-07-15 1966-07-11
FR69036A FR1486364A (fr) 1965-07-15 1966-07-11 Procédé et installation pour la fabrication de nappes fibreuses
DE1635572A DE1635572C3 (de) 1965-07-15 1966-07-12 Verfahren zur Herstellung von Glasfaservliesstoffen und Vorrichtung zur Durchführung des Verfahrens
NL6609795A NL6609795A (pt) 1965-07-15 1966-07-12
LU51552D LU51552A1 (pt) 1965-07-15 1966-07-13
SE09660/66A SE332137B (pt) 1965-07-15 1966-07-14
GB31699/66A GB1141815A (en) 1965-07-15 1966-07-14 Method and apparatus for producing a fibrous mat
US708462A US3544414A (en) 1965-07-15 1967-12-06 Apparatus for producing a fibrous mat

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US472100A US3381069A (en) 1965-07-15 1965-07-15 Method for producing a fibrous mat

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US3381069A true US3381069A (en) 1968-04-30

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US472100A Expired - Lifetime US3381069A (en) 1965-07-15 1965-07-15 Method for producing a fibrous mat

Country Status (8)

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US (1) US3381069A (pt)
BE (1) BE683958A (pt)
DE (1) DE1635572C3 (pt)
FR (1) FR1486364A (pt)
GB (1) GB1141815A (pt)
LU (1) LU51552A1 (pt)
NL (2) NL6609795A (pt)
SE (1) SE332137B (pt)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3791783A (en) * 1971-06-28 1974-02-12 Structural Fibers Apparatus for forming fiber preforms
US3882211A (en) * 1970-07-02 1975-05-06 Union Carbide Corp Method for the high speed production of non-woven fabrics
US4265979A (en) * 1978-06-05 1981-05-05 United States Gypsum Company Method for the production of glass fiber-reinforced gypsum sheets and gypsum board formed therefrom
US4950444A (en) * 1982-07-06 1990-08-21 Saint-Gobain Recherche Process for the formation of fiber felt containing an additional product
US4952128A (en) * 1987-09-22 1990-08-28 Chicopee Transverse web forming apparatus
US5143680A (en) * 1990-05-17 1992-09-01 Nordson Corporation Method and apparatus for depositing moisture-absorbent and thermoplastic material in a substrate

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB8527887D0 (en) * 1985-11-12 1985-12-18 Smith Eng Projects Ltd Web former

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA517591A (en) * 1955-10-18 W. Brooks Frank Brake
CA633360A (en) * 1961-12-26 Johns-Manville Fiber Glass Inc. Process and apparatus for producing a glass fiber mat
CA634668A (en) * 1962-01-16 Labino Dominick Process and machine for producing fibrous mats
US3081207A (en) * 1963-03-12 Fibrous mat and method of manufacture

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA517591A (en) * 1955-10-18 W. Brooks Frank Brake
CA633360A (en) * 1961-12-26 Johns-Manville Fiber Glass Inc. Process and apparatus for producing a glass fiber mat
CA634668A (en) * 1962-01-16 Labino Dominick Process and machine for producing fibrous mats
US3081207A (en) * 1963-03-12 Fibrous mat and method of manufacture

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3882211A (en) * 1970-07-02 1975-05-06 Union Carbide Corp Method for the high speed production of non-woven fabrics
US3791783A (en) * 1971-06-28 1974-02-12 Structural Fibers Apparatus for forming fiber preforms
US4265979A (en) * 1978-06-05 1981-05-05 United States Gypsum Company Method for the production of glass fiber-reinforced gypsum sheets and gypsum board formed therefrom
US4950444A (en) * 1982-07-06 1990-08-21 Saint-Gobain Recherche Process for the formation of fiber felt containing an additional product
US4952128A (en) * 1987-09-22 1990-08-28 Chicopee Transverse web forming apparatus
US5143680A (en) * 1990-05-17 1992-09-01 Nordson Corporation Method and apparatus for depositing moisture-absorbent and thermoplastic material in a substrate

Also Published As

Publication number Publication date
DE1635572B2 (de) 1974-05-16
DE1635572C3 (de) 1975-01-09
NL131118C (pt) 1900-01-01
NL6609795A (pt) 1967-01-16
FR1486364A (fr) 1967-06-23
LU51552A1 (pt) 1967-01-13
DE1635572A1 (de) 1972-03-23
GB1141815A (en) 1969-02-05
SE332137B (pt) 1971-01-25
BE683958A (pt) 1967-01-11

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