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Publication numberUS3512218 A
Publication typeGrant
Publication dateMay 19, 1970
Filing dateJan 19, 1968
Priority dateJan 19, 1968
Also published asDE1815021A1, DE1815021B2, DE1815021C3
Publication numberUS 3512218 A, US 3512218A, US-A-3512218, US3512218 A, US3512218A
InventorsLangdon Howard H
Original AssigneeCurlator Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Machine for forming random fiber webs
US 3512218 A
Abstract  available in
Images(5)
Previous page
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Claims  available in
Description  (OCR text may contain errors)

I H. H. LANGDON I MACHINE FOR FORMING RANDOMFIBER WEBS 5 Sheets-Sheet l Fiied Jan. 19, .1968

INVENTOR HOWARD H. LANGDON IGOJ FIG. 1

BY T

ATTORNEY MACHINE FOR FORMING RANDOM FIBER WEBS' Filed Jan. 19, 1968 5 Sheets-Sheefif:

FIG. 5

HOWARD H. LANGDON BY ATTORNEY IN VEN TOR [M5 19,1970; .H.H.Lmno- 7 ''3,512,21s

, I MACHINE FOR FORMING} RANDOM FIBER WEBS Filed Jan. 19, 1868 v 5 Shee t s -Sheet 5 :34 use FIG. 4

IINVE'NTOR HOWARD H LANGDON FIG. 5

' BY H mT ORNEY 'M ay'l alwo H-I'LLANGDON 3,512,218

' MACHINE FOR FORMING RANDOM FIBE'IR WEBS Filed Jan. 19, 1968 5 Sheets-Shee 4 FIG. 6

FIG. 7

INVENTOR HOWARD H. LANGDON @TORNEY HQH. LANGDQN mamas FOR FORMING RANDOM FIBER WEBS May 19, 1970 Filed Jan. 19, 1968 5 Shet-Sheet s INVENTOR HOWARD H. LANGDON ATTORNEY United States Patent US. Cl. 19-1563 8 Claims ABSTRACT OF THE DISCLOSURE In this machine fibers or tufts of fibers are fed to two rotating condensers on which the fibers are laid down by suction and from which the mats of fibers formed are dotted by doffing rolls, and fed over feed plates by feed rolls to two rotating lickerins which comb the fibers from the mats. The fibers are doifed from the lickerins by centrifugal force and by an air stream flowing through a balancing chamber disposed centrally between the two condensers and their feed plates. This stream is split by a saber, which is disposed between the two lickerins, so that it flows past the two lickerins. The split air stream (now two streams) delivers the fibers doffed from the lickerins onto an endless condenser belt on which the fibers are laid down in random fashion to form the random fiber web.

This invention relates to apparatus for producing random fiber webs, that is, for producing textile articles without spinning, Weaving, or knitting operations. In a more specific aspect, the invention relates to organized machines of the general type disclosed in the patents of Buresh and Langdon Nos. 2,700,188, 2,744,294, 2,876,- 500 and of Langdon et a1. 2,890,497.

One object of the present invention is to provide a machine capable of forming random fiber webs faster than prior such machines. To this end it is an object of the invention to provide apparatus for more efficiently producing random fiber webs, in which the product flow rate is increased.

Another object of the invention is to provide a machine of the character described suited to form random fiber webs With the best widthwise uniformity.

Other objects of the invention will be apparent hereinafter from the specification and from the recital of the appended claims, particularly when read in conjunction with the accompanying drawings.

In the drawings:

FIG. 1 is a fragmentary side elvational view, with parts broken away and shown in section, showing a random fiber web forming machine built according to one embodiment of this invention;

FIG. 2 is an elevational view, taken at right angles to FIG. 1 and partly broken away, showing fragmentarily the pneumatic feed system for supplying fibers to this machine;

FIG. 3 is an enlarged fragmentary sectional view showing, somewhat diagrammatically and on an enlarged scale, the structure of the lower part of the machine of FIG. 1;

FIG. 4 is a side elevation on a somewhat reduced scale of the machine;

FIG. 5 is a plan view of this machine;

FIG. 6 is a fragmentary View on an enlarged scale taken at the base of the machine and illustrating the mounting of the condenser screen on which the random fiber web is laid down;

FIG. 7 is a fragmentary sectional view on a still further enlarged scale showing the connection of the air exhaust duct to the condenser; and

FIG. 8 is a side elevation, with parts broken away, showing how hopper type feed mechanisms, instead of a pneumatic feed system, may be connected to the machine for feeding fibers to the machine.

Referring now to the drawings and first to FIGS. 1 to 7 inclusive, 10 denotes a pneumatic system for supplying fibers to the random fiber web forming machine, designated as a whole at 11. This fiber supply system may be similar to that disclosed in applicants pending application, Ser. No. 521,267, filed Jan. 18, 1966. It comprises a main line duct 12 which may be used to supply a line of machines, and which is connected by supply ducts 13 and 14 and by return ducts 15 and 16 to machine 11. The main duct 12 may be fed from any suitable source as, for instance, a conventional opener.

The ducts 13 and 14 deliver the air-conveyed fibers to trumpets 17 and 18, which form parts of the air bridge system conveying the fibers from the fiber supply source to rotary feed condensers 20 and 22.

The condensers may be of conventional construction, and comprise rotary screens 24 and 26 (FIG. 3) carried by end plates 28 and 30, respectively (FIG. 1) which revolve about fixed suction tubes 32 and 34, respectively. Each tube is slotted, as indicated at 35 (FIG. 3) in the case of the tube 32, along its length to suck the air through the screen 20 into the tube. The fibers are deposited on the screen.

Doffing rolls 36 and 38 are disposed in co-ntiguity to the condenser screens to doif from the screens onto feed plates 44 and 46' (FIG. 3), the mats of fibers laid down on the screens. Feed plates 44 and 46 are extensions of the plates that bound one side of the trumpets 17 and 18.

The mats are picked up by feed rolls 40 and 42, which feed the mats over the feed plates 44 and 46, and nose bars 48 and 50, respectively, to the rotary lickerins 52 and 54, respectively. These lickerins are of standard construction, as are the feed plates and the feed rolls.

The lickerins have peripheral teeth which comb fibers from the mats as the lickerins revolve. The lickerins are driven at high speed according to conventional practice; and the fibers are dotted from the teeth of the lickerins by centrifugal force and by air streams flowing over the teeth.

' The air streams for dotting the fibers from the lickerins are supplied through an intake duct 60 (FIG. 3) which passes through each side wall of the machine and may be fed by a pressure fan or fans. A restrictive slot 62 is provided in this duct 60 to equalize the widthwise flow into the chamber 64 through which the duct 60 extends. This chamber is of generally rectangular cross-section, and has ports 66 in its bottom through which the air flows to a balancing chamber 70 that is bounded by the downwardly converging walls 71, 72, and the side walls of the machine.

Mounted at the bottom of the chamber 70 is a saber 74, which is cylindrical in shape and is removable endwise.

The air flowing from duct 60 through chamber 70, splits at the saber 74, passes between the lickerins and the saber, and doffs the fibers from the lickerins. The air velocity is a maximum normal to the lickerins to aid in dofling of the fibers from the teeth of the lickerins. The fibers are then carried by the air streams through passages and 76 formed between cover plates 77 and 78 and the side walls 80, 82, respectively, of a chamber 83. The cover 77 may be relatively fixed but may be pivoted for cleaning about the axis of a doffing roll 84 that is contiguous to lickerin 52. The cover 78 is made in two parts hingedly connected to one another. It pivots at one end about the axis of a doffing roll 86; and it pivots intermediate at its ends on hinge 79. It is adjustable by adjustment of its lower part 81 for thickness or weight of the web being formed. Both covers preferably have Plexiglas or other transparent windows in them for observation purposes during operation, or may be made completely of Plexiglas. The dofiing rolls 84 and 86 aid in conventional manner the doffing of the fibers from the lickerins. They set up rotating swirls of air currents which materially aid the dofling of the fibers from the teeth of the lickerins.

The fibers doffed from the lickerins are deposited by the air stream on a condenser 85 which comprises an endless screen belt 90 that may be made of Fourdrinier screening and that travels over two pulleys 92 and 94 (FIG. 1) carried by rotary shafts 96 and 98, respectively. The undersurface 100 of cover section 81 has sealing engagement on its bottom surface with the top of the web carried by screen 90.

Mounted within the screen 90 is a suction box 102 which extends between the pulleys 92 and 94 (FIG. 1). It has sealing pads 104 on its upper surface which engage the inside of the screen as its upper reach moves over them, to insure optimum suction through the screen. It has a port 106 in its top into which the air streams flow by operation of a suction fan.

The rolls 92, 94, over which the condenser screen 90 travels are journaled by their shafts in frame plates 167 (FIG. 6) which carry stub shafts 171 on which are journaled rollers 173 that ride on rails 175 which are secured on top of the base of the machine. Thus, the random fiber web condenser can be slid, as a unit, out of the machine for cleaning or replacement.

The drive motor 170 (FIGS. 4 and for the condenser belt 90 is preferably a variable speed motor (FIG. 5) and may drive the belt through a belt and pulley, or chain and sprocket drive, or through gearing.

Fans mounted in housings 110 and 112 (FIGS. 4 and 5) create the high velocity air stream for doffing the fibers from the lickerins 52, 54 and for depositing the fibers in random fashion on the product condenser screen 90. These fans are connected to opposite sides of the suction box 102 (FIG. 3) by ducts 114 (FIG. 4), and deliver the air by ducts 116 and 118, respectively (FIG. 5) to opposite ends of the tube 60 (FIG. 3).

Through the side walls of the machine the air from these fans is also delivered through openings 120 (FIG. 3) in these side walls to the chamber 83. Air flows from chamber 83 in the form of air jets through openings 122, 124 beneath the saber 74 at each side thereof.

The air box 83 serves to aid in streamlining the airfiber flow from the saber to the condenser 90. If this air box were not provided there could be a serious turbulence pocket below the saber, upsetting the product web quality. This air box, due to clearance at 122, 124- between the saber tube and the side plates 80 and 82 of the air box also performs an important function with respect to product web quality. The clearance between the plate end and the saber is adjustable on each side of the saber and ordinarily is from .016" to .062". The air jets using full air pressure from the fans act to spill this turbulence pocket, with marked improvement in total air flow as well as in web quality.

The fans are driven by direct connected motors 126, 128. 1

Many of the parts used in the random fiber web machines illustrated in the Buresh and Langdon Pat. No. 2,876,500, granted Mar. 10, 1959, and in the Langdon et al. Pat. No. 2,890,497, granted June 16, 1959 may be used in the machine of the present application.

The lickerins 52, 54 are driven by separate directconnected motors 130, 132 (FIG. 5). The variable-speed, feed roll drive motor unit 176, 178 (FIG. 5) is located on top of the air box 64 and is connected to the feed rolls 40, 42 (FIG. 3) through gearing (not shown).

The suction on the feed condensers, which assists in deposit of the fibers thereon from the trumpets 17 and 18 (FIG. 3), is generated by fans 134, 136, respectively,

(FIG. 2) driven by motors 138 and 140, respectively, which are mounted on top of the chamber 64. The fans 134,136 suck the air through each of the feed condensers 20, 22 to one end thereof, and then through the ducts 142, 144 (FIG. 4), respectively; and the exhaust air is delivered by the fans 134, 136 to ducts 15 and 16 (FIG. 1), respectively, which return the air through connecting ducts 145, 146, respectively, to ports 147, 148, respectively, which communicate with the main duct 12 at the top thereof. A vane or damper (FIG. 1) pivotally mounted in the main duct 12 upstream of each supply duct 13, 14 determines whether fibers will be delivered to a particular supply duct, or carried on further to another machine in the line, as described with reference, for instance, to the machine of my application Ser. No. 521,267, above mentioned. By conducting the exhaust air into the main duct upstream of the associated supply duct, the returning air adds its pressure to the pressure of the main air flow in the duct 12 to prevent settling of fibers on the lower wall of the main duct. Further, this replaces the air Withdrawn from the duct 12 by the ducts 13 and 14, thereby to continue full circulating air in duct 12.

In the machine shown in FIG. 3, the feed plates-48 and 50 are of so substantial depth and are disposed to constitute extensions of trumpets 17 and 18, respectively, and of side walls 71 and 72, respectively, of balancing chamber 70. They form stabilizing members between the side plates 71 and 72 of the balancing chamber 70 and the opposed walls 73 and 75, respectively, of the trumpets 17 and 18, respectively.

The base section of the machine has a box section framework with cover plates top and bottom; and the longitudinal box sections are used as suction air ducts from the condenser unit to the inlets of the webber fans 110 and 112.

The mounting of the heavy side plates 162, 164 (FIG. 6) of the machine to the base section 160 by brackets 166, 168 along with the heavy section of the feed plates 44 and 46 (FIG. 3) provides structural stability.

The return air stream may be humidified with spray jets to eliminate static electricity so far as possible in the fiber flow, similar to the arrangement disclosed in the Buresh and Langdon Pat. No. 2,700,188, granted Jan. 25, 1955.

'FIG. 8- discloses alternate methods for feeding the random fiber web machine. Here two different hopper feeders 190, 192 are shown to illustrate the scope of possible use of the machine. Each hopper feeder is similar, in general, to the feed mechanism disclosed in the Langdon et al. Pat. No. 2,890,497, granted June 16, 1959. Each feed mechanism comprises a hopper 194, an endless floor apron or conveyor belt 195, traveling over pulleys 196 and 197. This conveyor belt carries the stock material in the hopper to an elevating apron or conveyor 198 which is mounted to travel over pulleys 200, 201, and which may be made of a plurality of slats in which there are embedded pins 202. A stripping apron 204, which travels over pulleys 205 and 206, and which is also provided with slats that carry pins, is mounted in cooperative relation to the elevator to strip fibers from the elevator apron.

The principal difierence between feeders and 192 is that feeder 190 incorporates feed rolls 222 and 224 and an oscillating gate 225, which is pivotally mounted in the side walls of this feeder, which is actuated by pressure of stock in the feeder to effect closure of a clutch to drive the feed rolls 222, 224 to cause these rolls to feed stock from the reserve box 220 into the hopper 194 in a manner similar to the feed rolls 46 of the Auten and Langdon Pat. No. 3,326,609, granted June 20, 1967.

The fibers are stripped from the elevating aprons 198 by an air stream traveling over the pins 202 by the suction in the ducts 13', 14' which deliver the fibers to the condensers 20', 22'.

Parts of the machine shown in FIG. 8, which are similar to the parts of the machine previously described are designated by the same reference numerals but primed. Here, however, the air is drawn by suction from the base 160' of the machine through ducts 210 to the pressure fans 212, which are connected by ducts 214 to the two ends of the air duct'60 in the balancing chamber 64'. The ducts 142 and 144 connect to motor driven fans 134, 136', respectively; but these merely exhaust to atmosphere. As before, a humidifier may be put in the box 161'. The stock material may be dumped into feeder 192. It may be fed to feeder 190 pneumatically through the reserve box 220.

With the machine described, for a given thickness of web, the product flow rate can be doubled as compared with prior machines through use of two feed systems, two rotaryv condensers, two lickerins, a single air stream split to doff fibers from the two lickerins, and a single product web.

With the present machine, moreover, the web weight is readily adjustable by adjustment of the position of cover section 81 (FIG. 3) with reference to the product condenser screen 90.

With the machine illustrated in FIG. 8 the feed con densers 24, 26 are part of the web-forming unit instead of, as previously, being part of feeder mechanism, such as shown at 190, 192'. This change makes it possible to form the feed mats close to the feed rolls. The air bridges function to strip the fiber tufts from the elevator aprons as needed, and these tufts drop vertically by combined gravity and air flow to the trumpets 17, 18. This insures widthwise uniformity in the product. This arrangement contrasts with prior constructions in which the feed condenser and associated parts are disposed at the air bridge and the feed mat has then to be transferred by conveying means to the feed roll for the lickerin. The separation of the air bridge and trumpet as shown in FIG. 8 makes it possible to form a very uniform feed mat, and hence a very uniform product web.

While the invention has been described in connection with diiferent embodiments thereof, it will be understood that it is capable of further modification, and this application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice in the art to which the invention pertains and as may be applied to the essential features hereinbefore set forth, and as fall within the scope of the invention or the limits of the appended claims.

Having thus described my invention, what I claim is:

1. A machine for forming a random fiber web comprising:

two spaced feed condensers mounted to rotate about spaced, parallel axes,

separate means for conducting tufts of fibers in air streams to said two feed condensers, to deposit fibers in mats thereon,

a feed plate disposed adjacent each condenser,

means for doffing the mat from each condenser onto the associated feed plate,

two rotary lickerins rotatable aboutaxes parallel to the axes of rotation of said feed condensers,

means for feeding the mats from said feed plates to the two lickerins so that the lickerins in their rotation comb fibers from the mats,

a chamber,

means for conducting an air stream into said chamber,

means for splitting said air stream into two separate air streams and directing the two streams past said two lickerins so that fibers are dotfed from the two lickerins by said air streams and by centrifugal force,

a movable product condenser disposed downstream of said lickerins, and

means for conducting said two separate air streams with the fibers dolfed from the two lickerins to said product condenser to deposit the fibers in random fashion on said product condenser to form thereon a single random fiber web.

2. A machine for forming a random fiber web comprising:

two spaced feed condensers,

separate means for delivering tufts of fibers to said two feed condensers, to deposit fibers in mats thereon,

a feed plate disposed adjacent each condenser,

means for dofling the mat from each condenser onto the associated feed plate,

two rotary lickerins,

means for feeding the mats from said feed plates to the two lickerins so that the lickerins in their rotation comb fibers from the mats,

means for directing an air stream past said two lickerins so that fibers are dolfed from the two lickerins by said air stream and by centrifugal force,

a movable product condenser disposed downstream of said lickerins on which the fibers doffed from the two lickerins are deposited in random fashion to form thereon a single random fiber web,

said air stream directing means comprising a chamber disposed between said condensers and into which air is flowed and opening at its bottom between said lickerins, and

a saber disposed at the bottom of said chamber to split the air stream flowing from said chamber into two streams flowing, respectively, past the two lickerins.

3. A machine as claimed in claim 2, wherein:

a second chamber is disposed beneath said saber,

means is provided for delivering a separate air stream to said second chamber, and

ports are provided in said second chamber adjacent opposite sides of said saber to direct jets of air at spaced points against said saber.

4. In combination,

a mainline duct for carrying air and fibers,

a random fiber web forming machine comprising two feed condensers rotatable about spaced, parallel axes,

two feed ducts connected separately to said mainline duct for conducting fibers and air to said condensers to lay down fibers on said condensers to form mats of fibers thereon,

a trumpet associated with each feed duct and constituting a prolongation thereof,

a feed plate associated with each trumpet and constituting a prolongation of one wall of the trumpet,

a fan for sucking air through each condenser from the associated feed duct and trumpet,

a duct connecting each fan to said mainline duct to return the air thereto,

a dofiing roll associated with each feed condenser for dotfing the mat of fibers therefrom,

a pair of lickerins rotatable on spaced parallel axes disposed below said two feed condensers, respectively,

a feed roll associated with each feed plate for feeding a mat therefrom to the associated lickerin so that the lickerin in its rotation will comb fibers from the mat,

a chamber disposed between said feed condensers, said chamber being open at its lower end,

means for directing a stream of air into said chamber that flows out its lower end,

a saber disposed at the open lower end of said chamber between said lickerins to divide the air stream issuing from the chamber and pass it by the two lickerins,

a product condenser disposed downstream of the lickerins,

walls bounding the space between the lickerins and said product condenser to conduct the divided airstream to said product condenser, and

means for sucking the air in the divided air stream through said product condenser and returning it to said chamber.

5. The combination claimed in claim 4, wherein:

opposite walls bounding said chamber converge downwardly, and

a portion, at least, of one of the walls bounding the space between said lickerin and said product condenser is adjustable relative to said product condenser to control the thickness of the web laid down on said product condenser.

6. The combination claimed in claim 4, wherein means is provided for projecting spaced jets of air at the under surface of said saber in the vicinities of said lickerins.

7. The combination with a machine for forming random fiber webs and:

comprising two feed condensers rotatable on parallel axes,

a feed plate associated with each feed condenser,

a duct for delivering air-borne fibers to each condenser,

a hopper associated with each duct for holding a supply of fibers,

means for delivering fibers from a hopper to the associated duct,

means for sucking air through each duct and its associated feed condenser to cause a mat of fibers to be laid down on each condenser,

two lickerins rotatable on parallel axes disposed below said feed condensers, respectively,

a rotary feed roll associated with each feed plate to feed the mat of fibers from the associated feed condenser over said feed plate to the associated lickerin to comb fibers from the mat,

r. saber disposed between the lickerins,

a chamber disposed between the feed condensers,

a product condenser disposed below said lickerins,

and means for sucking air serially through said chamber, past said saber, through said product condenser, and returning it back into said chamber,

said saber operating to divide the air sucked bysaid means into two air streams flowing past the two lickerins to doff fibers therefrom.

8. The combination claimed in claim 7, wherein :ad-

justable means is provided for controlling the thickness of the webs laid down on said product condenser.

References Cited- UNITED STATES PATENTS DORSEY NEWTON, Primary Examiner U.S. Cl. X.R. 19205

Patent Citations
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US3010161 *Feb 16, 1954Nov 28, 1961Wood Conversion CoMethod and means for producing mixed fiber suspensions in air and felts therefrom
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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3768118 *Jan 21, 1971Oct 30, 1973Johnson & JohnsonWeb forming process
US3772739 *Jan 21, 1971Nov 20, 1973Johnson & JohnsonWeb forming apparatus
US3862472 *Jan 5, 1973Jan 28, 1975Scott Paper CoMethod for forming a low basis weight non-woven fibrous web
US3914822 *Mar 14, 1974Oct 28, 1975Rando Machine CorpMachine for forming random fiber webs
US3972092 *Nov 26, 1974Aug 3, 1976Rando Machine CorporationMachine for forming fiber webs
US4223677 *May 11, 1979Sep 23, 1980Scott Paper CompanyAbsorbent fibrous structure and disposable diaper including same
US4240180 *Feb 7, 1979Dec 23, 1980Rando Machine CorporationFiber feeding apparatus for carding machines and the like
US4519114 *Dec 15, 1982May 28, 1985Rhyne Fibers, Inc.Apparatus and method for cleaning textile fiber
US4904439 *Jul 18, 1988Feb 27, 1990Johnson & JohnsonMethod of making a non-woven fiber web using a multi-headed ductless webber
US4921659 *Jan 17, 1989May 1, 1990ChicopeeMethod of forming a fibrous web using a variable transverse webber
US20020007169 *Mar 23, 2001Jan 17, 2002Weyerhaeuser CompanyAbsorbent composite having improved surface dryness
CN1789534BDec 15, 2005May 5, 2010阿瑟兰-蒂博公司Method and device for the transport of nonwovens
DE2202955A1 *Jan 21, 1972Aug 10, 1972Johnson & JohnsonBahn,insbesondere Faservliesbahn,und Verfahren zu ihrer Herstellung
DE3824569B4 *Jul 19, 1988Jul 15, 2004Johnson & JohnsonVorrichtung zur Herstellung einer Faserbahn
DE3824570B4 *Jul 19, 1988Jul 15, 2004Johnson & JohnsonVorrichtung zur Herstellung einer Faserbahn
DE3832098A1 *Sep 21, 1988May 3, 1989Johnson & JohnsonApparatus and process for the production of a fibre pad
EP1672110A1Oct 24, 2005Jun 21, 2006Asselin-ThibeauMethod and device for the transport of carded or air-laid nonwovens
WO2002088441A1 *Mar 28, 2002Nov 7, 2002ThibeauMachine for making a nonwoven by airlay technique, comprising a fibre dispersing chamber whereof the front wall is porous in the lower part
Classifications
U.S. Classification19/306, 425/82.1, 19/205
International ClassificationD04H1/72, D04H1/70
Cooperative ClassificationD04H1/72
European ClassificationD04H1/72