US2855879A - Tufting machine - Google Patents

Description

- TUFYTING MACHINE Filed March 23, 1956 4 Sheets-Sheet 1 HYDE AULJC VAQlAB I INVENTORS 050/705 MANN/N6 m [00/10 H. man/0mm ATTORNEYS Oct. 14, 1958 G. MANNING ETAL 2,855,879

TUFTING MACHINE Filed March 23, 1956 4 Sheets-Sheet 2 I jg l8 HYDQAULIC vmzwauz SPEED famuemgslcm INVENTORS GEORGE MA/V/Vl/VG 36 Y 3 7 EDGAR H. GRA/VBERRY ATTORNEYS Oct. 14, 1958 G. MANNING ETAL 2,355,879

- TUFTING MACI-IiNE Filed March 25, 1956 v 4 Sheets-Sheet 3 FIG. 4.

mvENToRS FIG 5 GEORGE MANN/N6 506/] R H. Gl-PA/VBERRY ATTORNEYS Oct. 14, 1958 G. MAN NING ETAL TUFTING MACHINE Filed March 23, 1956 i 4 Sheets-Sheet 4 INVENTORS ATTORI- IEYS GEORGE MANN/N6 EDGARMGRAIVBERRY United States Patent TUFTlNG MACHINE George'Manning, Gastonia, N. C., and Edgar H. Granberry, Shawrnut, Ala, assignorsto West Point Manufactoring Company, West Point, Ga., a corporation of Georgia Application March 23, 1956, Serial No. 573,408

9 Claims. (Cl. 112-79) This invention relates to tuftingmachines, such asl'are commonly employed in the production of bed-spreads, chenille cloth, rugs and the like. In particular, the invention relates to tufting machines adapted to'apply simultaneously to a base fabric multiple'rows-of chenille tufts or stitches in sinuous lines, to produce decorative and attractive overall tuft patterns or designs on the base fabric.

Multiple needle tuftingmachines, provided with one or more reciprocating needle bars' having sufiicient needles therein to cover the width of'a base fabric, are well known, a machine of this type being'illustrated and described in Patent No; 2,335,487 to Cobble et al. It is also knownto provide in conjunction with multiple needle machines feed mechanism for feeding extended lengths of material past the needle bars,-and to mount the cloth feed mechanism on acarriage movable transversely of the needle bars, whereby the base fabric may be displaced from side to-Side in passage through the machine in such manner that the needles stitch along sinuous lines. Typical mechanism of thisv type is disclosed in Patent. No. 2,513,261 to Beh-rens. Patterning operation oftuftingmachines involves the problems of suitablycoo-rdinating the forward-speed of the basefabric and its speed of movement in lateral direction with the operation of the needle'bars, and unless the fabric movements in both directions vary constantly with respect to the needle bar speed, the spacing between successive tufts or stitches appliedby any needlenecessarilyvaries. For example, if the forward feed of'the fabric is maintained constant with respect to theneedle. bar operation, the spaces between successive stitches applied in alineinecessarily varies whenever the rate oftransverse movement of the fabric changes.

It is a principal object of the present invention to pro-- verse directions, wherein the base-fabric feed'in both i directions is coordinated by means of a hydraulic variable. speed transmission, the speed ratio of which is controlled through a unique feed back arrangement.

A further object of the invention is to provide an improved multiple needle tufting machine of simplified and rugged construction, requiring minimum maintenance and attention: I

Still another object is the provisionof a versatile tufting machine of thepatterningtype, incorporatingpro- Ice vision forsimplified quick. changezof the-patternapplied,

needle tuning-machine, irrrwhich. the presentiinvention is incorporated;

Figure 2 is a perspectiveview ofthe deviceeofFigure I; viewed from the right and somewhat rearwardly; showing the drive connection to theforward-fabrio feeds;

Figure 3is a schematic diagram of the.invention-,'.the drive train-being modified for thesakc of simplicity;

Figure 4 illustrates an exemplary pair ofrcamsuseful in the invention, and the sinuoussingle-meedle stitch line resulting from its-use;

Figure 5 illustrates adiife rent pair of cam's-useful ln place of .the cams of Figure 4, and the distinctivesinuous singlelneedle stitch line achieved byits'use;

Figure .6 illustrates. the overall pattern resultingpfrom multiple needle operation with the cams offigurefi; I Figure 7 illustrates.aasinglewcurved stitching line; and constant stitch spacing thereal0ng,.;and t Figure .8 diagrammaticallyillustratestheessential I613!- tionship in maintaining uniform stitch spacing along a curved line such as that of Figure 7.- I r The drawings, and in particulanFigures land 3, illustrate. the invention as appliedto a conventional multiple needle tufting machine,.iticludingtheusual frame.l0-sur'- mounted by amain driveshaft 12,..the "latter being driven byany suitable source of power such-aselectric motor14. As. will be understood, the vmainadrive.slriaft. .lZ-mayrbe eccentrically linked to .the/needle bars f the-machine in conventional manner,,whereby rotation ofinthei drive shaft effects reciprocation of the needle bars with respect to the base fabric. The machine may also include the usual throat plate (not shown) on which thefabricrests to be pierced by the needles, andlooping andcuttinggmechanisms driven in timed relatio-nto the "needle. bars,- preferably from themain drive shaft. As indicatedvin Fig re 3, the exemplary. machine is :provided with fourneedlebars 16, each mounting a row of needles,-although 'it wil-lrbe as well. I I

In the illustrative embodiment,v meansforfeeding the base fabric past .theneedle' bars andsmeansforrrnoving the fabric transversely thereofare both driven :in;-coo rdi understood that more orfewerneedle bars maybe utilized nated manner with respect -.to the-needle bar. drive; .p refer-' ably directly from the mairirdrive shaftofithe machine. Both fabric drives. are efiected throughaa.singleivariable speed transmission a 18, preferably a,= hydraulic variable speed transmission provided with theusual side c ntrol shaft Zlland controlarm l2iextending therefromnwRot-ation of the. control .shaft ill-through alsmall arc rof moyemerit, it wil'beunderstood, is .adaptedlto vary the speed ratio of the hydraulic transmission, whereby it may transmit. power at aspeedratiovaryingfrcml) to lllfigp of theinput thereto, ,the speed ratio variation bearings-a sub-- stantially l linear. relationship .to rotative movement of the control shaft through a small are. As shown, theanain 38 is transmitted by means of a gear 40 on its output shaft through intermediate gears 42, 44'and 46 to a drive gear 48ifirr'ed1y mounted one. stub shaft .50 suitably. journaled or stitches to the base fabric.

stantly varying rate.

on the machine, the axis of the stub shaft conveniently extending in the direction of normal fabric feed through the machine. The tufting machine is provided with a conventional feed carriage 54, suitably supported as by rollers 56 on transversely extending guide ways 58, whereby the carriage is movable transversely of the machine. The carriage mounts the usual leading and trailing feed rolls 60 and 62, adapted to maintain the base fabric taut and feed it over the throat plate of the machine past the needle bars. The feed rolls may be provided with suitably roughened surfaces, and may function with cooperative backing rolls, in the well known manner.

A pair of correlated cams 64 and 66 are fixedly mounted on the stub shaft 50 to rotate therewith. A suitably braced guide structure 68 extending laterally from the frame side supports a transversely movable slide 70, which is rigidly engaged to the feed carriage 54 as by a rod 72. Twin cam followers 74 extend outwardly from the slide 70, and engage between them the periphery of cam 64, which is disposed closely adjacent the slide. Conveniently, the stub shaft 50 is supported by the guide structure 68, and may extend through a suitable slot in the slide 70. The cam 64, as shown, is eccentrically mounted on shaft 50 whereby rotation of shaft 50 and cam 64 will effect transverse reciprocation of the slide with respect to the machine frame, and corresponding transverse back and forth movement of the feed carriage 54, the cycle of transverse movement depending on the contour of the cam.

A cam follower 76, mounted at one end of a lever arm 78, is disposed and adapted to engage the shaped edge of the other cam 66. Lever arm 78 is pivoted at 80, and its other end is engagedby a rigid link 82 to the control arm 22 of the transmission 20. A spring 84 extending from the end of lever arm 78 remote from cam follower 76 to the machine frame is provided to maintain the cam follower 76 constantly in contact with the edge of cam 66.

Referring to Figure 2, the rotation of gear 44 is transmitted through its supporting shaft 88 to a helical gear 90 mounted on the opposite shaft end, and gear 90 is drivingly' engaged to a similar gear 92 carried by a shaft 94 extending transversely of the machine. Shaft 94 is engaged by means of its gear 96 through an idler 98 to a gear 100 mounted on shaft 102, which is drivingly engaged by an axially sliding connection 104 (Figure 3) to the leading feed roll 60. The trailing feed roll 62 may be rotated by frictional engagement of the fabric passing through the machine, or it may be positively driven in unison with the leading feed roll 60, as by means of the feed roll pulleys 106 and 108, linked by belt 110.

In operation, a length of fabric extends over feed rolls 60 and 62, passing between the throat plate of the ma- -chme and the needle bars 16. As the drive shaft 12 rotates, the needle bars are reciprocated, and the needles thereon periodically pierce the fabric and in cooperation with associated mechanism apply transverse rows of tufts In the present invention, the feed rolls are driven continuously, except in some cases for momentary periods of rest, although it will be evident that the fabric section immediately beneath the needles is periodically halted instantaneously by entry of the needles thereinto, these momentary interruptions to movement however being readily accommodated by the inherent stretch of the fabric. While the feed rolls ro- -'tate continuously, the rotation of the feed rolls is at a.

constantly or frequently varying rate, due to the variable speed transmission in the drive train thereto. Similarly, the cross feed of the fabric is continuous and at a con- The forward feed and the cross feed both derive from the same transmission, and the output of the transmission is fed back by means of the speed control cam 66 to vary the speed ratio thereof, in

accordance with a pre-determined pattern established by the contour of cam 66. This transmission speed ratio control by feed back from its output is highly effective and efficient in achieving precise and even stitch spacing along sinuous or other irregular stitching lines.

The cross feed cam 64 and the speed control cam 66 must of course correspond, and must be arranged in proper phase relationship, whereby the forward feed will be at a maximum when the cross feed is zero, and at a minimum when the cross feed is at its maximum. An illustrative pair of cams is shown in Figure 4, wherein the feed carriage (cross feed) cam 64A is circular and eccentrically mounted, the speed control cam 66A having the corresponding shape illustrated. This cam combination is effective to give the base fabric passing through the machine an overall sinuous movement whereby each needle stitches along a line such as 112 on the base fabric, the line 112 in this case approximating a sine wave. The dimension line 114 indicates a single cycle of stitching, corresponding to one complete revolution of the cams. When using two needle bars in the machine, every needle will stitch a line of the shape of line 112, and a longitudinally aligned needle on the other bar may stitch a similar line one-half cycle out of phase, as indicated by the dotted line 116, the stitch lines 112 and 116 crossing and re-crossing to form the pattern illustrated. This requires, of course, that the length of a stitch cycle (line 114) be precisely twice the distance between needle bars.

Another illustrative and correlated set of cams is illustrated in Figure 5, wherein the cams 64B and 66B are both of irregular contour. The cross feed cam 64B is shaped to effect a step-wise transverse reciprocation of the feed carriage, and the speed control cam 66B is correspondingly shaped to effect the single needle stitch 'line 118. Dimension line 120 indicates a complete cycle of stitching along line 118.

In Figure 6, an overall pattern which may be effected by the cam pair of Figure 5 is illustrated, this figure showing the stitch lines of three adjacent needles on each of four needle bars, the three needle groups used for purposes of illustration being aligned longitudinally of the machine. The complete overall pattern is evident in the dotted line box 122, and it will be seen that six different needles contribute to this section of the overall pattern. It will also be observed that in this case the spacing between adjacent needles on each needle bar is equal to the spacing between needle bars, and the stitch clearly evident in Figure 6.

In applying a pattern by the means described, successive tufts or stitches applied by the individual needles are invariably spaced evenly from each other, along the stitch lines which may be curving or otherwise irregular. Figure 7 illustrates a semi-circular stitch line section 124, along which stitches 126 are positioned. It will be noted that the spacing between all stitches 126 is equal, measured along the extended length of line 124. The automatically achieved constant stitch spacing may, however, be readily varied as desired, merely by varying the relationship between the speed of main drive shaft 12 and the input of the variable speed transmission 18. For example, the even stitch spacing may be reduced or increased merely by replacing either pulley 26 or the transmission input pulley 30 with a similar pulley of different diameter. While the spacing between stitches may be thus readily altered, the new stitch spacing will be even and constant throughout the pattern applied. Such expedient may also be utilized to vary the length of the design period or cycle.

The problem of cam design is essentially simple. The

calIy. A simplev graphical method is illustrated in Figure 8. To apply a semi-circular pattern'line suchas 128, it will -be understood that thecross feed cam must be designed to effect cross feed from point C' topoint D and return in a portion of the cam cycle. Such transverse movement may be effected, for example, by rotation of an eccentrically mounted circular cam such as cam 64A (Figure 4) through a half cycle or 180.

If is .alsoexpedient to determine initially the desired stitch spacing. Forexample, if the normal needle speed is. 600lstitches per minute, andit is desired to applyv 20 stitches per inch along the pattern lines, then the maximum forward speed of the fabricmust be 30 inches per minute. Thisrepresents thenormalforward feed of the fabric when the cross feed is Zero, and is the desired relative velocity between the needlesand the base fabric at allftimes;

The point on the cross feed. cam 64--corresponding to zero I rate of cross feed is readily determinable, and the speedcontrol cam at the. corresponding point must position the cam. follower 76 to achieve the desired feeding speed of the feed rolls 60 and 62, in the assumed case 30 inches per minute. As cross feed of the fabric is initiated, the rate of forward feed of the fabric must'be reduced, in accordance withthe direction. of cloth movement relative to the needles, or in accordance with the slope of the pattern .line. being, applied. At point E'on line 128, for example, the needle movement with respect to the base fabric is in the direction of line EF, andthe forward speed of thefabric, if the relative velocity is to be maintained at 30 inches .per minute, must be 30 times cosine 6, being the angle of divergence between the relativedirection of the cloth and the line of normal feed as shown. At point. G, the normal forward'feed of the fabric must beat the rate of. 30 times cosine 6. In this manner, the rate of forwardspeed may be determined at equal intervals alongthe pattern line. For example, if the period'or cycle of a pattern line has an extended length of. 10 inches, the forward speed might be determined graphically, at half inch intervals along the line. Theseequally spaced intervals will correspond to equally angularly spaced points on the speed control cam, and each-acorresponding cam point may be laid out to effect the desired forward speed at that moment of the cycle. At point H (Figure 8-) in the cycle when the cross feed is at a maximum, in this case inches per minute, the forward feed must momentarily be zero, and the correspond ing point on the speed change cam must suitably position' the cam follower 7'6'to this end. At point Iffalong the pattern line, the cross feed'is momentarily zero, andth'e corresponding point on the speed change cam must position the cam follower 76 to effect a forward feed of 30 inches per minute. The transmission having a substantially linear speed ratio variation, the laying out of intermediate forward speed points is essentially simple. In most cases symmetry will greatly reduce the cam layout work.

In the machine illustrated, change from one pattern to another is readily and quickly accomplished. This requires only removal of the cams 64 and 66 from the machine, as by unlocking them and sliding them out over the adjacent end of the shaft 50, and replacement of a similar cam set corresponding to a different pattern. Reference marks or keys and keyways may insure quick and correct alignment of the cams on the shaft. The cam followers '74 and 76 engaging the cams only peripherally, they do not interfere with the cam replacement, except that it is convenient to swing lever arm 78 well out of the way. When the new cams have been locked in place, production with the new pattern may proceed immediately, no other machine changes or adjustment being required, except in radical pattern ly-elfected' by circular sections on the cams.

6 changes which require changes in the number bars to be utilized 'orthe like. I

of needle While the stitch lines illustrated are continuously curving, it willbe understood that the patterns applied may comprise'straight line segments, these being readi- Similarly, while the invention has been described in connection with a machine in which the fabric feed mechanism is is reciprocabletransversely, it will be understood that the invention is applicable as well to similar machines in which the feed rolls do not move in axial direction, but in which a feed carriage is utilized to reciprocate the needlebars, throat plate and associated elements from.

hereinbefore set forth, together with many practical ad-" vantages, are successfully achieved; As various possible embodiments may bemade of the mechanical features of "the above invention, all without departing from'the scope thereof, it is to be understood that all matter hereinbefore'set forth or sh'ownin theaccompanying drawings'is to be interpreted as illustrative, and'not in a limiting-sense.

we claim:

1. In a' tuftingmachine including a frame, a reciprocatory needle bar mounted in said frame, means for driving "said needle bar, means for feeding base fabric past said needle bar, andlmeans permittingrelative transverse movement'betweeni said feeding means and said needle bar; a variable speedtransmission, means for driving the input of said transmission at a speed bearing a fixed relationship to the speedofsaid needle bar drive, means engaging the output of said transmission to' said fabric feeding means in driving relationship, a pair of cams; means engaging'the output of saidtransmission to said" cams in driving relationship, means engaging one of said'cams to said transversemovement means to control the movement thereof, and means engaging the other of said cams 'to'said transmission to control the speed ratio thereof.

2 In a tufting machine including a frame, a reciprocatory' needle bar mounted in said'frame, means for driving said needle bar, and transverselymovablemeans for feeding-base fabric past said: needle bar;'a variable speed transmission, means for'driving' the input of said transmission ata speed bearing a fixed relationship to the speed of said needle bar drive, means engaging the output of-saidtransmission tosaid fabricfeeding means indriving-relationship, a pair" of cams, means'engaging the-output of said transmission to said cams in driving relationship, means operatively engaging one of said'cams to said fabric feeding means to control the transverse movement thereof, and means engaging the other of said cams to said transmission to control the speed ratio thereof.

3. In a tufting machine including a frame, a recipro catory needle bar mounted in said frame, means for driving said needle bar, means for feeding base fabric past said needle bar, and means permitting relative transverse movement between said feeding means and said needle bar; a hydraulic variable speed transmission, means for driving the input of said transmission at a speed bearing a fixed relationship to the speed of said needle bar drive, means engaging the output of said transmission to said fabric feeding means in driving relationship, a pair of rotary cams, means engaging the output of said transmission to said cams in driving relationship, means engaging one of said cams to said transverse movement means to control the movement thereof, and means engaging the other of said cams to said transmission to control the speed ratio thereof. l

4. In a tufting machine including a frame, a reciprocatory needle bar mounted in said frame, means for driving said needle bar, and transversely movable means for feeding base fabric past said needle bar; a hydraulic variable speed transmission, means for driving the input of said transmission at a speed bearing a fixed relationship to the speed of said needle bar drive, means engaging the output of said transmission to said fabric feeding means in driving relationship, a shaft, a pair of rotary cams mounted on said shaft, means engaging the output of said transmission to said shaft in driving relationship, means operatively engaging one of said cams to said fabric feeding means to control the transverse movement thereof, and means engaging the other of said cams to said transmission to control the speed ratio thereof.

5. In a tufting machine including a frame, a reciprocatory needle bar mounted in said frame, means for driving said needle bar, means for feeding base fabric past said needle bar, and means permitting relative transverse movement between said feeding means and said needle bar; a hydraulic variable speed transmission, means for driving the input of said transmission at a speed bearing a fixed relationship to the speed of said needle bar drive, means engaging the output of said transmission to said fabric feeding means in driving relationship, a shaft, a pair of rotary cams removably mounted adjacent an end of said shaft, means engaging the output of said transmission to said shaft in driving relationship, means peripherally engaging one of said cams to said transverse movement means to control the movement thereof, and means peripherally engaging the other of said cams to said transmission to control the speed ratio thereof.

6. In a tufting machine including a frame, a reciprocatory needle bar mounted in said frame, means for driving said needle bar, and transversely movable means for feeding base fabric past said needle bar; a variable speed transmission, means for driving the input of said transmission at a speed bearing a fixed relationship to the speed of said needle bar drive, means engaging the output of said transmission to said fabric feeding means in driving relationship, a shaft, a pair of rotary cams removably mounted adjacent an end of said shaft, means engaging the output of said transmission to said shaft in driving relationship, means operatively and peripherally engaging one of said cams to said fabric feeding means to control the transverse movement thereof, and means peripherally engaging the other of said cams to said transmission to control the speed ratio thereof.

7. in a tufting machine including a frame, a reciprocatory needle bar mounted in said frame, means for driving said needle bar, and transversely movable means for feeding base fabric past said needle bar; a hydraulic variable speed transmission, means for driving the input of said transmission at a speed bearing a fixed relationship to the speed of said needle bar drive, means engaging the output of said transmission to said fabric feeding means in driving relationship, a pair of cams, means engaging the output of said transmission to said cams in driving relationship, means operatively engaging one of said cams to said fabric feeding means to control the transverse movement thereof, a cam follower engaging the other of said cams, and means engaging said cam follower to said transmission to control the speed ratio thereof,

8. in a tufting machine including a frame, a reciprocatory needle bar mounted in said frame, means for driving said needle bar, means for feeding base fabric past said needle bar, and means permitting relative transverse movement between said feeding means and said needle bar; a variable speed transmission, means for driving the input of said transmission at a speed bearing a fixed relationship to the speed of said needle bar drive, means engaging the output of said transmission to said fabric feeding means in driving relationship, a pair of cams, means engaging the output of said transmission to said cams in driving relationship, means engaging one of said cams to said transverse movement means to control the movement thereof, and means engaging the other of said cams to said transmission to control the speed ratio thereof, said cams being of correlated shape to maintain uniform stitch spacing along curved stitching lines applied by said needle bar to said base fabric.

9. In a tufting machine including a frame, a plurality of reciprocatory needle bars mounted in said frame, means for driving said needle bar, and transversely movable means for feeding base fabric past said needle bar; a hydraulic variable speed transmission, means for driving the input of said transmission at a speed bearing a fixed relationship to the speed of said needle bar drive, means engaging the output of said transmission to said fabric feeding means in driving relationship, a pair of rotary cams, means engaging the output of said transmission to said cams in driving relationship, means operatively engaging one of said cams to said fabric feeding means to control the transverse movement thereof, and means engaging the other of said cams to said transmission to control the speed ratio thereof, said cams being of correlated shape to maintain uniform stitch spacing along curved stitching lines applied by said needle bars to said base fabric.

References Cited in the tile of this patent UNITED STATES PATENTS 1,757,795 Dahlen May 6, 1930 2,335,487 Cobble et a1 Nov. 30, 1943 2,513,261 Behrens June 27, 1950 2,595,585 Kline May 6, 1952 2,724,352 Gentry et al. Nov. 22, 1955

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