US2944412A - Method of making pile fabrics - Google Patents

Description

July 12, 1960 4 w. A. RICE 2,944,412

METHOD OF MAKING PILE FABRICS Original Filed Dec. 4, 1957 3 Sheets-Sheet 1 Q BY a 6 PZWZ %47 ATTORNEYi July 12, 1960 w. A. RICE METHOD OF MAKING PILE FABRICS 3 Sheets-Sheet ,2

Original Filed Dec. 4, 1957 FIG. 2 f r I N V EN OR. A

July 12, 1960 w. A. RICE 2,944,412

METHOD OF MAKING FILE FABRICS Original Filed Dec. 4, 1957 3 Sheets-Sheet 3 FIG. 3

IN/IgNTOR. 4 ca ATTORNEY? 2,944,412 METHOD or MAKING min FABRICS.

Walter A. Rice, Amsterdam, N.Y., assignor to Mohasco Industries, Inc., Amsterdam, N.Y., a corporation of New York Original application Dec. 4, 1957, Ser. No. 760,655. Di-

vided and. this 2 Claims. (CI. 66-85) This invention relates tothe'production ofpile fabrics application Oct. 7, 1 958,'Scr. No.

ate:

and is concerned more particularly witl a novel method of knitting such fabrics which are especiallyladapted for use as floor coverings, The fabrics "made bly tlie practice 0f the. method have .a .dense pile made of loops and the, loops 7 are of, different heights and disposed" in accordance with a pattern so that the pile ,ha'sfian interesting sculptured appearance. I v I The method ofthe invention produces fabrics of the warp type, which include a base or backing made up of a plurality of chains of stitchesqof warp yarns connected by back weft threads. The stitches in the chains are. aligned in courses extending transversely of the fabric and the backweftthreads extend laterally back and forth and are laid in stitches in the same course in adjacent chains. The pile surfaceof the fabric is made of heavy pile'weft yarns, which are laid in the stitches of the chains and are raised between adjacent chain inaltethe pile r are laid in thesti'tch from areservoir and laid in stitches inadja'cent ehains with the portions of th'e yarns betw'eengthe chains held l t of the plane of the chains to fforhi'loops. "The "yarns are fed from sources of supply toward the res in increments, which vary in length in accordance witha pattern, and at the end of each knitting cycle carried out on the machine, the'pile loops-between adjacent chains are released and fixed uniform lengthsef the yarns fed inincre nents are directed into the reservoir. ihe increments of pile-weft yarns fed as determined by-the pattern are, in some instances,-of less lengththan-the fixed uniform lengths, and, ,in any cycle, infwhich 'an increnrade of cotton 'andthe chain's lie close'together with the stitcheslqf'the chains "aligned incourses transversely of the fabric. V I

"ljhe warp'chains are connected and held in proper spaced relation by back Weft threads 12, which are preferabiy stiff and made of jute or paper. Each back weft thread is of regular sinuous form and it is laid in the stitches in the same course of a plurality of adjacent chains. In the construction shown, each lateral stretch 12a of a backweft thread passes through stitches in four chains and reverses direction'and passes through stitches in the next course infour chains, after which the thread again reverses direction. At each point of reversal of a back weft thread, "it tightlyengages and is bound in successive stitches in a single chain. Thela terally extending stretches of adjacentweft threads overlap, so that each warp chain is connected in each'course to the adjacent warp chains on either side'thereof by three back weft threads and four 'backw'eft threads pass through each chain stitch. If desired, each stretch of each back weft thread'may cross more or less than three warp chains and the strength and a stability of the fabric vary directly with the number of warp chains crossed. Preferably, each back weft thread crosses at least'three warp chains.

v The pile ofthe fabric is provided by heavy multi-ply yarns 13, 14, 15, 16, which are made of wool or 'ofa'lny o'fthe fibres ordinarily used in the pile yarns of floor covering' fabric's. Each pile yarn is laid back and forth in the stitche's' o'f -a plurality of adjacent chains and, in the fabric 'shown, each pile yarn is of regular sinuous "f'orni and crosses and connects. three adjacent chains. Thus, "as shown in Fig. l, the top stretch of the pile Weft cha'in'siltlb, 1'0q,"10,reverses' direction and passes through "stit'ches in the next. lower coursei'n the chains '10, 10a,

"adjacent yains 'tw er'lap"andstretches of at least three different p'i'le yarns are-laid in each warpchain stitch.

'In each lateral stretchof eachpile yarn in the fabric ijllustratedja portion'of the yarn'israised out'o'f the fabmerit of a yarnfed is shorter than the fixed hni form-length of the yarn directed into the reservoir, the movement of suchlength o'f yarn into'the reservoir causes yarn to be drawn from the last-formed loop thereof "and the loop is shortened. The height of the pile loop formed of any yarn in a knitting cycle thus depends on the length of the increment of that yarn fed during the cycle. I

For a better understanding of the invention, reference may be made to the accompanying drawings in which Fig. 1 isan expanded diagrammatic plan View on an enlarged scale of one fo-rnroffabric knitted by the method of the invention; i 7

Fig. 2 is a vertical sectional view of a {knitting machine, on whichthe method of the invention can be practiced;

Fig. 3f view in side elevation "of one element of a pattern chain employed on the machine of Fig. 2; and a ric'to forma pil'e'loop'lyin'g between two of the three chains crossed by the yarn and, in the next lateral stretch of 'they'a'rn, a portion of the yarn is raised to form a loop lying between'the-other two chains of the three crossed by the yarn. Thus, the yarn' 13 is'raised between the stitches in chains 10, 10a to form a loop 17 and the portion of the same stretch of the yarn, which connects stitches" ofchains 10a, 1%, lies buried in the fabric. In

the next lateral stretch of the yarn 13, the portion lying between the stitches in the chains 10, ltla lies buried in v the fabric, while the portion between the stitches in the chains 10a, 10b is raised to form the loop 17a; 'The other pile yarns form loops in the same manner with the resnlt that, in any longitudinal 'row of loops, adjacent loops are made of different yarns frhus, the loop -1' 7aof yarn 1'3 in the fabric the-height of the loops varies in accordance with a pattern and; in the section of the fabric 'iShQWnin Big: 1; all of the loops in the outer longitudinal rows are high cloops, while all the loops 17a, 18af form s n eda 1a 0' 3 extends from'ri'ght to left through stitches inthfe elaborate and intricate pattern effects may be obtained in the pile.

The method of the invention may best be practiced on warp knitting machines of the Raschel type, which have a row of needles and a row of points mounted for pattern and, at the end of each knitting cycle, the lengths of yarn fed in increments are directed into the reservoir. The lengths of certain of the increments drawn from the supplies are shorter than the fixed uniform lengths required for laying about the points and, in any cycle, in

which the length ofa yarn increment fed is shorter than the fixed uniform length of the yarn directed into the reservoir, yarn is drawn from the loop of. that yarn formed in the cycle and the loop is correspondingly reduced in height. The height of the loops throughout the fabric thus depends on the lengths of pile yarn fed in increments in the cycle, in which the loops were produced.

The pile yarns maybe fed in increments varying in length in accordance with a pattern by feeding apparatus .of various types. such as the apparatus disclosed in the US. patents of Crawford 2,853,034, Thompson 2,781,007, or MacCalfray 2,784,689, or the British patent to Card 735,019. The Crawford feeder is preferred and a Raschel machine, which may be used in the practice of the method and is provided with the Crawford apparatus, is illustrated in Figs. 2-4, incl. The machine includesa row of needles 19 mounted in leads 20 attached to a bar 21'which is mounted on levers 22 oscillated by a cam-actuated link 23 to reciprocate the needles in a substantially vertical plane. The individual needles lie in slots in a trick plate 24 and, in the operation of the machine, the needles are projected above the top of the plate and later retracted to the positions shown .in Fig. 2. YA second trick' plate 25 lies spaced from plate 24 and a row of points 26 mounted in leads 27 attached to a bar 28, are movable in the slots in plate 25. 'The bar 28 ,is secured to a lever 29, which is mounted on shaft 30 oscillated by suitable means. The points 26 lie at the same spacing as the needles and are aligned with the needles.

A rock shaft 31 mounted above the trick plates, carries arms 32 connected by rods 33, on which are mounted bars carrying the guides for the threads. The bar 34 carries guides 35 for the back weft yarns 12, the guides being mounted in leads attached to the bar 34. .The guide bar 36 carries a row of guides 37 for the pile yarns P while the bar 38 carries guides 39 for the yarns C for the chain stitches. Each bar carries as many guides as there are needles and the guides on each bar are spaced a distance equal to the spaces between adjacent needles and points.

The pile yarns P are drawn from individual sources of supply in the form of packages in a creel and the yarns pass beneath a guide rod 40 to the feeder, in which the yarns pass between a series of bars 41 mounted on parallel chains 42 and a second series of bars 43 mounted on parallel chains 44. The chains 42 are trained about a plurality of sprocket wheels 45 and one of the sprocket wheels marked 45a is mounted on a shaft '46 carrying a sprocket wheel 47 driven by a chain 48 from a suitable moving part of the knitting machine. The chains 44 are similarly trained about sprocket Wheels 49 and one of the sprocket wheels marked 49a is mounted on a shaft 50 driven in unison with shaft 46 by appropriate means. The chains 42 and 44 have parallel stretches, in which the bars 41 intermesh with the bars 43, and the yarns P pass between the outer ends of the bars in these stretches and are gripped and fed by the barsfi The bars 43 are of uniform height from .end to end while the bars 41 have sections indicated at a, b, c, d, e,

etc., the sections varying in height in accordance with a pattern and each section having a width to be engaged by single yarns. In passing between the intermeshing bars 41, 43, each yarn is deviated from a. straight line across the ends of bars 43 by its engagement with the outer edges of the bars 41 and the amount of such deviation between each two bars 43 depends on the height of the pattern section on the bar 41 engaged by the yarn between the two bars 43. The chains 42, 44 are driven in unison during the operation of the machine at such a rate that each chain advances by one bar during each knitting cycle. As a consequence, an increment of yarn is released from'between successive bars 43 at the lower end of the parallel stretches of the chains 42, 44 during each cycle and the length ofthe increment is the length of the deviated yarn lying between the pair of bars 43. The length of such an increment of each yarn varies with the pattern section on the bar 41, which produces deviation of the increment, and the amounts of the yarns fed in successive cycles thus vary in accordance with the pattern as determined by the shape of the bars 41.

i The yarns fed in increments by the bars 41, 43 pass beneath a guide rod 51 carried by brackets 52 attached to a longitudinal member 53 of the knitting machine structure. Each bracket 52 carries a pivot 54, on which is mounted a lever 55, and the levers are connected by a rod 56, which is square in cross-sectionand lies at one side of the pivot, and a rod 57, which is round in crosssection and lies at the other side of the pivot. The levers 55 are rockable by links 58, which are adjustable in length and connect the levers 55 to one end of levers 59 fast on a shaft 60 mounted for oscillation on the machine framework. Shaft 60 carries an arm 61 having a roller 62 engaging the edge of a cam 63 mounted on a shaft 64 and a spring 65 connected to a bracket 52 and a lever 59 maintains roller 62 against the edge of cam 63. When the roller 62 is on the low part of cam 63, the levers 55 are held at such an angle that the yarns fed by bars 41, 43 may pass in-a straight line from beneath guide rod 51 to and over guide rod 57. When the high spot of cam 63 causes shaft 60 torock counter-clockwise, the levers 55 are rocked'clockwise with the result that the rod 56 engages the yarns from above and deviates them out of the direct path from between the guide rods 51, 57. The increase in length in each yarn between guide rods 51, 57 resulting from deviation of the yarn by rod 56 constitutes a reservoir of the yarn for use in the knitting operation.

In the production of the fabric in accordance with the method of the invention on the knitting machine shown, the first step in each knitting cycle is the vertical movement of the point bar 28 to the position shown in Fig. 2. The shaft 31 is then swung to cause the guides 37 for the pile yarns to move to a position in front of the plane of the points, after which the guides are moved laterally or shogged to cause the pile yarns to be lapped about respective points. During the occurrence of these operations, the levers 55 have been moved to the inclined position shown in Fig. 2, so that the guide rod 56 is out of contact with the yarns between the guide rods 51, 57. The fixed uniform lengths of pile yarn previously deviated by rod 56 between rods 51, 57 are thus made available for lapping about the points and may be just suflicient for this purpose. The usual knitting steps are then carried out, during which the guides all swing to the rear of the points, the back weft yarn guides are shogged, the guides all swing forward of the points, and the needles .are raised. Thereafter, the guides all swing to the rear of the needles, the chain yarn guides are shogged to lap the warp chain yarns about respective needles, and the guides all swing forward. At this stage, the pile yarns are lapped about respective points and are laid across a plurality. of chains, the back weft yarns are each laid across a plurality-0f chains, and each chain yarnis lapped about aneedle. ,The needles then descend to'draw new loops through the. old ones at the edge .of the fabric and,

. rality of chains.

when this action has been completed, each pile yarn and each back Weft yarn are bound in stitches in a plu- Thereafter, the points descend to free the loops of pile yarn. The final step in the cycle is the restoration of the reservoir of pile yarns and, for this purpose, the levers 55 are swung clockwise so that the guide rod 56 engages the yarns from above and deviates them downward between the guide rods 51, 57 to place fixed uniform lengths of the yarns in the reservoir. 7

During the knitting cycle, the chains 41, 44 have advanced by one bar each to release an increment of each pile yarn from between the parallel stretches of the chains. If this increment is equal to the fixed uniform length of such yarn in the reservoir and is thus-sutficient to permit the formation of a pile yarn loop of maximum height therefrom, that is, a loop lapped about a point, the downward deviation of the yarns by the action of rod 56 will just take up the increment. However, if the increment of any yarn is less than the fixed uniform length and insufiicient for formation of a loop of maximum height therefrom, the deviatingaction of bar 56 will 7 ing on the side of at least one of said points remote from cause a fixeduniform length of the yarn to be placed in the reservoir 'and'the difference between the increment fed and the length of yarn required for the formation of a loop of maximum height will be drawn fromthe loop of that yarn'just formed. Accordingly, in the practice of the method, a pile loop of maximum height is initially formed in each knitting cycle with the yarn required for such loop made available by release of the fixed uniform length of the yarn in the reservoir andby the feeding of an increment of yarn in the cycle. At the end of each knitting cycle, a fixed uniform length of each yarn is restored to the reservoirand such action may reduce the height of a pile loop formed and boundin. the stitches of the chains in the cycle. The height of the loops of pile throughout-the fabric thus depends on the length of. successive increments of the pile yarn fed and. is determined by the formation of the bars 41 on. the pattern chains 42.

In the fabric illustratedfthe pile 'yarnsi'a re laid in stitches in the samecourse in three adjacent'chains with Y the yarn raised'betwee'n .two of the chains toforma 100p "and lying buried between the other'twochains this arrangement, the loops in any longitudinal row throughout the fabric are formed alternately of two different yarns with attendant advantages in avoidanceof .formation of. streaks. However, ,itis not necessaryfthat With I the needles to lap the yarn about the point and form a loop and on the needle side of the rest of 'said points, the

pile weft yarns being longitudinally offset by the distance between adjacent points and all the pile weft yarns being lapped about different points and being laid in opposite directions in successive cycles, laying a plurality of back weft yarns along the row of points on the needle side thereof with each back weft yarn extending across at least three points andadjacent back weftryarns longitudinally offset by the distance between adjacent points, the back weft yarns being laid in opposite directions in successive I cycles, advancing the needles, lapping chain warp yarns simultaneously about'respective needles with each chain yarn overlying a plurality of pile andlback weft yarns, retracting the needles to form stitches in respective chains.

with a plurality of pile and back weft yarns bound in each of the stitches, each pile weft yarn being bound in chain yarn stitches on opposite sides of the portion of each yarn forming a loop about a point, retracting the points to release the loops of pile weft yarns thereon, and, after release of the loops,moving into the reservoir increments from the sources of supply, the movement into the reservoir of a fixed uniform length of a pile weft yarn, of which the increment fed during the cycle is shorter'than'the length of yarn required for laying across ence in length between said incr ement and the length of v, the yarn required for lapping about a point.

a portion of each pileyarn be buried ineach course and,

I if preferred, the fabric maybe constructed with the pile yarns laid in stitches in two adjacent chains only in each course. r

This application is a division of my co-pending application Ser. No. 700,655, filed December 4, 1957, now abandoned.

I claim: 7

1. A method of knitting a pile fabric on a knitting 2. The method of claim 1,-in which the pile and weft yarns are laid in stitches in the same course in at least "three chains. 1 I p 1 References Cited in the file of this patent UNITED STATES PATENTS 2,531,718 Rice Nov. 28, 1950 2,718,132 Herrnstadt Sept. 20, 1955 2,842,079 Rice July 8, 1958 2,842,259 Hoeselbarth July 8, 1958 Crawford Sept. 23, 1958

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