US3627215A

US3627215A - Strand-handling equipment

Info

Publication number: US3627215A
Application number: US801232A
Authority: US
Inventors: Hans H Richter
Original assignee: Leesona Corp
Current assignee: Leesona Corp
Priority date: 1969-02-03
Filing date: 1969-02-03
Publication date: 1971-12-14
Anticipated expiration: 1988-12-14

Abstract

Strand-traversing mechanism having a pair of oppositely traveling belts each with yarn-engaging guides for moving the yarn along a traversal path with effectively uniform controlled movement and transferring the yarn to an oppositely moving guide at reversal ends of the path. During transfer of the yarn from one guide to another, the portions of the belts on which the guides are mounted are directly supported on pulleys which steady the guides. Pulleys intermediate the traversal path further steady the guides and cause the guides to move to and fro across the strand of yarn for effectively preventing grooving of the guides. The traverse belts are preferably formed from timing belts having on one belt face teeth for direct positive drive by correspondingly notched pulleys and each yarn engaging guide is preferably connected to its belt by a clamp passing at least substantially entirely around the belt and replacing one of the teeth on the belt face.

Description

m 1 1 1 I, 1,2 l 111 l ililfl Stes tell [1113 627315 1 1 Inventor HIM Rk'mwr 3,393,880 7/1968 Keith et al. 242/45 W M- 3,491,962 1/1970 Roberts 242/43 [21] 801,232 FOREIGN PATENTS [22] Filed Feb. 3, 1969 [45] Patented Dec. 14 119.71 972,440 8/1950 France 242/158 B [73] Assignee mm Communion 1,422,593 11/1965 France 242/158 B Warwick, 1R.l. Primary Examiner-Stanley N. Gilreath Continuation-impart of application Ser. No. Anorneys-Albert P. Davis and Burnett W. Norton 724,875, Apr. 29, 1968, now abandoned. This application Feb. 3, 11969, Ser. No. 0 3 Y ABSTRACT: Strand-traversing mechanism having a pair of oppositely traveling belts each with yarn-engaging guides for moving the yarn along a traversal path with effectively uniform controlled movement and transferring the yarn to an [54] sTBANDHANDUNG EQUHPMIENT oppositely moving guide at reversal ends of the path. During 38 Claims. M Dmwmg m transfer of the yarn from one guide to another, the portions of the belts on which the guides are mounted are directly sup- [52] US. Cl. 2 42/43, ported 0n pulleys which steady he guides p l i 242/153 B mediate the traversal path further steady the guides and cause [51] lint. Cl. 136511 54/28 the guides to move to and f across the Strand f yam f f. [50] Field of Search 242/43, 43 f ti l preventing grooving f the guides h traverse belts 158 B are preferably formed from timing belts having on one belt face teeth for direct ositive drive by corres ondin ly notched [56] References Cited pulleys and each yarft engaging guide is pre ferably connected UNITED STATES PATENTS to its belt by a clamp passing at least substantially entirely 2,238,128 4/1941 Nydegger 242/158 B X around the belt and replacing one of the teeth on the belt face.

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NS H. [RICHTER ATTO R N EYS STRAND-HANDLING IEQIIJIIFMIENT The invention relates to strand traversing mechanism for winding apparatus and, more particularly, to a belt traverse, the present application being a continuation-in-part of application Ser. No. 724,875, filed Apr. 29, 1968, now abandoned.

Throughout the specification and claims, the term "yarn" is employed in the general sense to apply to all types of strandular material whether textile or otherwise, and the term package" is used to designate the product of a winding machine, whatever its form.

As is more fully discussed in other Leesona Corporation U.S. applications of Hans l-I. Richter, Ser. No. 600,553, filed Dec. 9, 1966, and Ser. No. 601,471, filed Dec. 13, 1966, industrial demands for higher speed precision winding machines require higher traversing speed of the yarn than can readily be obtained merely by speeding up present precision winding traverses. There are existing mechanisms for fonning precision wound cylindrical packages, but they do not operate at a sufficiently high speed to satisfy present demands. For example, there is the reversible yarn guide mechanism, but inertia of the reversing guide limits the operating speed of the mechanism. The helical grooved traversing roll, while not a precision winding device, produces difficulties when operated much above its normal speed, primarily in that the yarn jumps out of the reversing ends of the groove.

Still another known type of traversing mechanism is commonly called a belt traverse. Belt traverse mechanisms have not been industrially suited for precision winding. These traverses use one or two belts which carry guides operating in opposite directions along the traversing path of the yarn. Theoretically, they can overcome the difficulties encountered with reversible yarn guide traverses and traverse rolls since there is no inertia factor with belt traverse guides because these guides do not reverse direction while in contact with the yarn and there are no groove problems as with a helically grooved traverse roll.

Difficulty has been encountered with belt traverses during transfer of the advancing strand of yarn from one guide to another guide moving in the opposite direction. Such transfer presents different problems as the traversing speed changes. For example when starting to wind a new package, the traversing speed is at its greatest and decreases as the diameter of the package increases. This is because a greater length of yarn must be wound onto the package for each revolution of the package as its diameter increases. Therefore, with the yarn traveling at constant lineal speed, progressively lower traversing speed is required as the package diameter increases. As will be apparent later, different problems are en countered at these different speeds.

Another difficulty in the performance of belt traverses occurs because of even slight uncontrolled movement of the yarn guides, even minor vibration being an undesirable factor during transfer of the yarn. While the inherent nature ofa belt traverse is such that vibration is slight, the transfer of the yarn between oppositely moving guides results in slight jolting and this may be reflected in vibration of the belts and guides. Also, momentum of the yarn as it is transferred from one guide to another causes the yarn to continue to move in its original direction after it has been released from the delivering guide and an outward bending of the yarn about the guide followed by springing when released from the guide is particularly troublesome. Additionally, the loss of tension at the moment of transfer may result in stitches, rollover, slippage or other erratic action of the yarn.

The invention, in brief, is directed to a belt traverse mechanism in which effectively uniform controlled movement of an advancing strand of yarn is obtained at reversal end portions of its traversal path. Such improved functioning is obtained by careful control ofa combination of contributing factors. These factors include improved yarn guides, better control of the guides, restraining free traversing movement of the yarn by means of a friction member to reduce undesirable effects of inertia of the yarn and springing back of the yarn during transfer at the reversal ends, and by maintaining the yarn constantly tensioned within relatively close limits during its transfer between oppositely moving guides at the reversal ends.

It is a primary object of this invention to provide a new and improved traversing mechanism.

Another object is to provide a new and improved belt traverse for precision winding.

A further object is to provide a new and improved belt traversing mechanism capable of precision winding at higher speeds than has previously been industrially obtainable. A related object is provision in such a mechanism for providing improved yam transfer between oppositely moving guides at reversal ends of the traverse path. Another related object is provision for providing effectively uniform controlled movement of the guides. Still another related object is provision for retarding inertia and springing back effects in the advancing strand of yarn during reversal, and for maintaining the yarn constantly tensioned during reversal.

A still further object is an improved timing belt for traversing yarn having spaced driving teeth formed on one side of the belt and at least one yarn engaging element substantially rigidly affixed thereto by means of a clamp engaging opposite sides of the belt and replacing one of the driving teeth.

These and other objects and advantages of the invention will be apparent from the following description and the accompanying drawings in which:

FIG. l is a schematic, and elevational view of a winding machine including an embodiment of the belt traverse mechanism of this invention;

FIG. 2 is a fragmentary schematic, front elevational diagram of a portion of the winding machine, with parts broken away and removed for clearer illustration;

FIG. 3 is an enlarged, schematic front elevational view of the traverse mechanism, with parts broken away and removed for clearer illustration;

FIG. 4 is a schematic top sectional view taken generally along the line 4--4l in FIG. 3, with parts broken away and removed for clearer illustration;

FIG. 5 is a fragmentary, enlarged vertical sectional view as if taken generally along the line 5-5 in FIG. 3 but with yarn guides in the position shown in FIG. 9:,

FIGS. 6-9 are fragmentary, enlarged top views showing the yarn guides during transfer of the advancing strand of yarn from a delivering guide to a receiving guide and, more particularly, FIG. 6 is a sectional, view taken. generally along the line ti6 in FIG. 3, and FIGS. 7-9 are progressive views of the guides changing position during transfer of the yarn;

FIG. 10 is a fragmentary, vertical sectional view of a modified preferred embodiment of the invention;

FIG. ll is a detail view of a portion of FIG. l0 taken in cross section through the guide in order to show the precise mode of attachment;

FIG. 12 is a fragmentary perspective view of a modified arrangement for mounting the yarn guide element on the timing belt, showing the belt fragment in engagement with a driving pulley;

FIG. 13 is a detailed plan view of the modification of FIG. ill; and

FIG. M is a detailed cross section view taken generally along the line lid-14 of FIG. l3.

As shown in FIG. ll of the drawings, a winding machine receives an advancing strand of yarn if from a suitable source of supply (not shown). The strand moves in the direction of the arrows about a tension compensating guide 10 fixed on the free end of a compensator arm 12 fixed to a pivoted shaft 13 from which the yarn passes through a traverse mechanism M to a yarn package P releasably held on a rotating spindle 16 mounted on a pivoted arm 17 and urged against a roller bail 1b.

Lineal speed of the advancing yarn Y is maintained constant by decreasing the rotational speed of the package P as the diameter of the package increases and, more particularly, as

the compensator arm 12 moves with its pivot shaft 13 responsive to slight increase (or decrease) in yarn tension to decrease (or increase) the rotational speed of the package and maintain substantially constant speed of the advancing strand of yarn and therefore substantially constant yarn tension, as is well understood in that art.

As is more fully described in related Leesona Corporation patent applications of J. V. Keith and Hans H. Richter, Ser. No. 537,526, filed Mar. 25, I966, and Ser. No. 712,142, filed Mar. 1 l, 1968, when the yarn passes through the tension-compensating guide it forms a U-shaped loop 20 supported on a pressurized cushion of air. This cushion of air causes the yarn loop 20 to move inwardly (dotted lines) and outwardly (phantom lines) within the guide to compensate for fluctuations in tension resulting from variations in length primarily because of traversing of the yarn. With reference to FIG. 2, as the yarn is traversed between opposite reversal ends 22 of its traversal path 24 (FIGS. 2 and 4-9) the length of the yarn varies from the tension-compensating guide to guides 26 of the traverse mechanism 14. This length is greatest at the reversal ends 22 and least at the midpoint 28 of the traversal path 24 and, but for the guide 10, would result in minor fluctuations in yarn tension and length causing the compensator arm 12 to pump up and down. Jumping movement of the arm would result in loss of control of tension in the advancing strand were it not for the tension compensating guide 10 which constantly maintains tension by compensating for fluctuations in the length of the yarn as it passes through the guides 26 of the traverse mechanism 14.

The traverse mechanism 14 may be best seen in FIG. 3 and in FIG. 4. A body or frame 30 of the traverse mechanism includes a lower member 32 and an upper member 34 fixedly connected as by posts 36 adjacent opposite ends of these members. Flexible belt means, here illustrated in the form of an upper timing belt 38 and lower timing belt 40, move (as indicated by the arrows in FIG. 3) in opposite directions on timing belt wheels or sprockets. The upper belt 38 passes about a receiving sprocket 42 and then a larger intermediate sprocket 44 and a delivering sprocket 46. then around a driven sprocket 48 and again over the intermediate sprocket 44 and an idler sprocket 50 before again passing around its receiving sprocket 42. The lower belt 40 passes through a similar course but passes around a receiving sprocket 52 adjacent the delivering sprocket 46 of the upper belt 38, then about a larger intermediate sprocket 54 (FIG. 3) and a delivering sprocket 56 adjacent the receiving sprocket 42 of the upper belt 38, then about an idler sprocket 58 (FIG. 3) and again the intermediate sprocket 54 before passing about a driven sprocket 60 (FIG. 3) and back to its receiving sprocket 52. These sprockets are suitable journaled on shafts with the upper shafts 62 fixed to the lower plate 32. As shown at the right end of FIGS. 3 and 4, the upper and

lower drive sprockets

46 and 60 are integral with the upper and lower driven

pulleys

66 and 68, respectively, and may be driven in any suitable manner as by upper and

lower drive belts

70 and 72, respectively. Thus, with the belts riding on the delivery and receiving sprockets during transfer, and with the intermediate pulley further stabilizing the belts, vibration and uncontrolled movement of the guides is effectively eliminated.

The yarn traversing guides 26 are fixedly secured to the

belts

38 and 40. Each belt has at least two equally spaced guides 26 which extend into parallel slots 74 (FIGS. 3 and 5) of a yarn regulator and guide assembly 76 (FIGS. 3-5). This assembly provides the yarn traversal path 24 as it guides the yarn parallel to the package P and retards deflection to the package of any undesirable springing or acceleration of the yarn during transfer between the guides 26 at the reversal ends 22. The assembly 76 has three parallel bars 78 spaced apart to form the slots 74. In the illustrated embodiment, the inner faces 80 of these bars 78 and longitudinally straight and smooth with rounded edges. As illustrated, the inner faces 80 are convex and they may have flats or other configurations and be associated aligned or offset (with the strand passing between opposed faces of the bars) as shown in the abovementioned Richter applications, or they may be arranged in other suitable manners and with other suitable configurations for providing sufficient frictional engagement with the yarn Y without damaging the yarn (depending on the particular yarn and its finish) to retard movement of the yarn along the bars 78 and thus reduce the effect of any acceleration or springing of the yarn during transfer at the reversal ends 22. High friction surfaces may be highly polished chrome plated surfaces and may be differentiated from low friction surfaces which may be a furnished chrome plated surface resulting in less area contact with the advancing yarn as is generally provided the roller bail 18 to prevent scuffing of the yarn. The bars 78 are fixed at either end to plates 82 removably and adjustably secured to ears 84 on the lower and upper plates 32 and 34 as by nuts 86 and bolts 88 extending through horizontally elongated slots 90 in the ears 84. Thus, the assembly may be changed for an assembly having different friction characteristics or different arrangement of the bars, and may be adjusted toward or away from the guides for optimum performance with difierent deniers or types of yarn Y. As may be seen in FIG. 5, the path of the advancing yarn holds it against the faces of the bars 78.

As a guide 26, for example on the upper belt 38, leaves its receiving sprocket 42 it moves toward the bars 78 up to the midpoint of the large intermediate sprocket 44 and thereafter moves away from the bars as it moves toward its delivering sprocket 46. Thus, the yarn propelling surface 92 (FIGS. 6-9) of the guide 26 moves normal to the bars 78 and back and forth across the yarn Y as this surface moves the yarn along the traversal path 24 (that is bar faces 80), thus effectively preventing grooving of the surface 92.

With reference to FIGS. 3-9, a guide 26 receiving the yarn Y is now referred to as a receiving guide 26R" and a guide delivering the yarn Y is now referred to as a delivering guide 26D." As the yarn Y is traversed from right to left in FIGS. 3 and 4, it is moved along the bars 78 by a delivering guide 26D on the lower belt 40. This guide 26D delivers the advancing yarn Y to a receiving guide 26R on the upper belt 38 at the left-hand reversal end 22. As the receiving guide on the upper belt is moved to the right it becomes the delivering guide and delivers the advancing yarn Y to the other lower belt receiving guide 26R at the opposite (right-hand) reversal end.

In order to form a suitable package P, uniformly controlled movement of the yarn is maintained during transfer at the reversal ends 22. With the yarn moving in the straight traversal path 24 along the faces 80 of the bars 78, it is carried by the delivering guide 26D on a straight portion 96 of the propelling surface 92, and this straight portion is generally perpendicular to the bars 78 and the traversal path 24. It is this straight portion 96 of the surface 92 which rides to and fro across the yarn as the intermediate sprockets move the belts and their guides first toward and then away from the traversal path 24 of the yarn. As the lower belt 40 just starts to bend about its delivering sprocket 56, as may best be seen in FIG. 6, the delivering guide 26D has moved inwardly from the traversal path 24 and the yarn Y is moving onto a curved free end portion 98 of the surface 92. With reference to FIGS. 7 and 8, as the lower belt 40 bends about its delivering sprocket 58 the yarn Y rides across the free end portion 98 of surface 92 of the delivering guide 260 and this portion 98 is curved opposite the direction of movement of the guide 26 and, more particularly, curved'so as to maintain substantially constant velocity of the strand of yarn. But for this curved free end portion 98 of the surface 92, as the guide moved along the curvature of its delivering sprocket 58 the velocity of the yarn along the traversal path 24 would be increased thus reducing the quantity of yarn deposited on the end portion of the package P, and this would result in a groove about the cylindrical end of the package.

As the receiving guide 26R on the upper belt 38 and the delivering guide 26D pass each other (FIG. 9), the strand of yarn Y passes across the tip of the curved free end portion 98 of the propelling surface 92 of the delivering guide 26D and against the propelling surface 92 of the receiving guide 26R. This coaction of the delivering and receiving guides is provided by offsetting the axes of the adjacent delivering sprocket and receiving sprocket. More particularly, the receiving sprocket i2 is offset outwardly from the axis of the delivering sprocket M in the direction of the traversal path 24! of the yarn, and inwardly in a direction toward the path 2 1. Thus, with reference to FIGS. 5 and 9 (which show the guides 245D and 2t5R in the same position), when the delivering and receiving guides pass each other the straight surface 96 of the receiving guide 26R extends outwardly across the traversal path 2d of the yarn to receive the yarn, and the yarn siips off of the tip of the free end portion 9% of the delivering guide 26D. At the moment of transfer, momentum of the yarn tends to maintain its direction of movement but, with reference to FIG. 2, at this time the yarn is following the lineal path shown at the left side of FIG. 2 and also tends to spring to the right when it is released from the delivering guide 26D. Such springing may be a problem at the lower traversing speeds.

When starting to wind a new package the relatively high traversing speed is generally sufficient so that the momentum of the yarn and speed of the receiving guide 26R coact to maintain the yarn against the receiving guide propelling surface 92. The critical factor at higher speed operation is to avoid accelerating the strand as it is leaving the delivering guide 25D and this is accomplished by the previously discussed curvature of the free end of the delivering guide surface 92.

However, at slower traversing speed the momentum of the yarn is less but the yarn maintains its tendency to spring along its traversal path in the direction of movement ofthe receiving guide 26R and away from the receiving guide propelling surface 92. If permitted, such uncontrolled movement of the strand would result in grooving of the package because of the momentary higher than normal traversing velocity of the strand resulting from such springing. To control the strand and to retard this velocity surge caused by the springing effect of the strand during transfer at slower traversing speeds, an abutment ltll], generally parallel to the straight portion 96, is pro vided on the guide and this abutment provides a slot 101 parallel with and leading the propelling surface 92 in the direction of movement of the guide. As the moment of transfer of the yarn approaches, the receiving guide 26R is moving about its receiving sprocket (412 or 52) and toward the yarn traversal path 24. The receiving guide abutment we passes (and may slightly tip) the yarn (FIG. 9) and then moves across the traversal path 24 to stop the yarn from free springing along the traversal path in the direction of movement of the receiving guide 26R. Angulation of the receiving guide 26R relative to the traversal path 24 results in some acceleration of the yarn as the guide is moving to a perpendicular position along the path, and this has been found to effectively prevent high ends" on the package P. High ends result from reversal of the strand of yarn at the ends of the package, since more yarn is deposited at the ends than elsewhere, as is understood in the art. Such acceleration of the yarn by a receiv ing guide is reflected in the package only at the very portion in which the direction of the yarn undergoes reversal and does not result in grooving. To further control movement of the yarn, the bars 78 retard movement of the yarn along the traversal path 24 and therefore deflection of the springing effect to the package P.

A preferred embodiment of the invention is shown in FIG. 10 and is substantially the same as the previously described embodiment (with similar parts having the same reference number as before, but primed) other than that the upper guides 102 and the lower guides 104 are vertically disposed relative to each other as closely as is practicable and are preferably substantially contiguous, and subject only to production limitations may slide over each other as they pass. To this end they may be suitably coated and have their leading edges beveled to smooth engagement with each other. However, if desired, a separating strip (not shown) may be provided between the upper and lower guides and this strip may be coated with a low friction substance such as Teflon. Two friction bars 111th provide one slot 10% which, as shown in FIG. 10, is preferably as narrow as possible. Having the

guides

102 and 10 3 as close together as possible and in such a narrow slot 111b, results in better control of the yarn during transfer. First of all, in the embodiment of FIG. 10, there are shorter free spans of yarn between the two guides 102 and 1M and between the guides and the bars 106, than in the embodiment of FIG. d. Secondly, in the mechanism shown in FIG. 5, when the yarn is carried by the lower guide (as 26D) during transfer, rather than the upper guide (as 26R), there is additional frictional drag of the middle bar 78 and a longer span of yarn to the upper bar 78, resulting in different characteristics of the opposite ends of the package In the embodiment shown in MG. 10, the distances from the upper and

lower guides

102 and 104 to the upper bar 1116 are substantially the same, as are the resultant opposite ends of the package P.

Also revealed in FIGS. 10 and 11 is one mode of attaching the yarn engaging guide element 261), 26R to the timing belts. These belts 38', 40' are provided on their inner faces with regularly spaced teeth designated 110, 111 for engaging with corresponding notches 112 on the belt-engaging sprockets 42, 414, as, 48, 50 (see FIG. 4). It is, of course, necessary that the guide elements be firmly and securely attached to the belts since detachment of an element during operation at the high speeds contemplated by the invention would be extremely hazardous to personnel. Inasmuch as appreciable weakening of any section of the belt to receive a supporting clamp for the element, which would be required ifa clamp was located in an area between two belt teeth, is precluded for the same reason,

the preferred mode of attaching each. of the elements according to the invention is to remove one of the teeth of the belt, as by grinding or cutting, and affix the element in the space thereby provided.

As can be seen in FIGS. 10 and till, the inner end of each guide element 261), MR, i.e. adjacent the belt, is extended from the element body generally in the shape of a U or a channel 120, 1121 having a width substantially the same as the belt width so as to snugly receive the belt therein, and the opposite leg 122, 123 of the channel is bent toward the element body in the manner ofa flange at 124, 125, partially closing the channel opening. Cooperating with the flanged U- or channelshaped extension is a

clamping plate

126, 127 of generally L- shape in cross section, the leg 128, 129 of the 1.. extending in parallel contacting relation to the inner portion of the element body and the base 130, 131 seating against the outer belt surface with its remote end engaged beneath the flanged end 124, of the extension. A clamping screw 132, 133 penetrates an aperture formed in the base leg 130, 131 of the clamping plate, passes through the belt, which may be punched for the purpose, and engages a tapped aperture in the U-shaped extension.

The dimension of the extension 120, 121 lengthwise of the belt is not greater than the length of a tooth of the belt in order that the clamping structure moves freely and easily within the pulley grooves. Similarly, the thickness of the extension cannot exceed that of the tooth although in most instances a considerably lesser thickness will suffice as FIG. 10 indicates. Since the structure as described is, in effect, wrapped essentially entirely around the belt, accidental detachment from the belt is virtually impossible.

A modified form of attachment for the guide elements is illustrated in FIGS. 12-14, wherein prime designations are used for the same parts. It may occasionally be observed that the ar rangement of FIGS. 10 and 11 is subject to some tendency to rock slightly about the locus of its attachment, i.e. about an axis passing through the belt perpendicularly of its lengthwise axis. While this tendency is seldom serious, extremely precise positioning of the guides is advantageous and reduction in this tendency is beneficial. Also, the mass of the guide element is concentrated at one edge of the belt and at extremely high speeds, centrifugal force may tend to lift that edge away from the driving pulleys, causing uneven belt wear. A more balanced system would avoid this problem.

The modified arrangement is designed to counteract both of the just-described difficulties. Thus, the free leg of the U- or channel-shaped extension is projected above the outer face of the clamping plate 126', 127', as at 140, 141, before being bent reentrantly, as at 142, 143, to provide a slotlike recess 144, 145 (see P16. 14). The clamping plate 126, 127' is stamped out in the shape of a T when viewed in plan and the crossbar of the T 146, 147 is bent at right angles to the plane of the leg of the T to form an upstanding ear fitting into the slotlike recess 144, 145. The ends 148, 149, 150, 151 ofcrossbar 146, 147 to project to each side of the channel leg 122, 123 and as they lie in a plane perpendicular to the rocking axis, the guide is effectively braced against rocking movement except in concert with flexing of the belt. Moreover, the upstanding crossbar 146, 147 provides mass to at least partially balance the mass of the

guide elements

26R, 26D, and the thickness and weight of the clamping plate can be selected with this function in mind.

The clamping plate 126', 127' which forms the staff of the T for crossbar 146, 147 is held in place by a screw 132, 133 as before.

It is not necessary to remove material from the belt to form openings for the clamping screws. A sharp pin forced through the belt will create a passage sufficient for penetration by the screw and the resultant compression of the belt material around the screw shank assists in holding the screw in place.

Only one traverse belt has been included in the illustration of the modified embodiment of FIGS. 12-14, but it will be ap preciated that where the belts are used in pairs, as is normally the case, the second belt would be similarly constructed except that it would appear as a mirror image of the belt shown in the drawings. To indicate this fact, double numerical designations have been applied in these figures.

While this invention has been described with reference to particular embodiments in a particular environment, various changes may be apparent to one skilled in the art and the invention is therefore not to be limited to such embodiments or environment except as set forth in the appended claims.

What is claimed is:

l. A yarn-winding machine comprising, a rotatable spindle, yarn-engaging means for traversing an advancing strand of yarn axially of said spindle to wind a package of yarn, and guide means for directing said yarn-engaging means in a first path as the yarn is traversed onto a first zone of said package, said guide means being operable to direct the yarn-engaging means in a second path diverging from said first path as the yarn is traversed onto a second zone of said package, said first and second paths being offset relative to the axis of said spindle.

2. The combination as set forth in claim 1 wherein said guide means includes rotatable means for directing the course of said yarn-engaging means.

3. The combination as set forth in claim 2 wherein said yarn-engaging means further includes endless means.

4. The combination as set forth in claim 3 wherein said endless means is disposed to define one of said first and second paths as a path inclined relative to the axis of said spindle.

5. The combination as set forth in claim 3 is disposed to define both of said first and second paths as inclined relative to the axis of said spindle.

6. The combination as set forth in claim 3 wherein said endless means include first and second oppositely moving spans, said yarn-engaging means including at least one yarn engaging member on each span.

7. The combination as set forth in claim 6 wherein said rotatable means includes separate first guides proximate a first end of the package for guiding an associated one of said first and second spans past said first package end and said rotatable means further includes separate second guides proximate a second end of the package for guiding an associated one of said first and second spans past said second package end, the axes of said first guides being offset relative to each other, and the axes of said second guides being offset relative to each other.

8. The combination as set forth in claim 7 wherein the axes of the respective first guides and the respective second guides are offset from each other in a plane perpendicular to the package axis.

9. The combination as set forth in claim 7 wherein the axes of the respective first guides and the respective second guides are offset from each other in a plane parallel to the package 3X15.

10. The combination as set forth in claim 7 wherein the axes of the respective first guides and the respective second guides are offset relative to each other both in a plane perpendicular to the package axis and in plane parallel to the package axis.

11. Apparatus as set forth in claim 1 including means providing substantially constant tension in said strand during traversal thereof in said first and second paths.

12. A yarn-winding machine comprising, a rotatable spindle, first means for traversing an advancing strand of yarn axially of said spindle in a first direction, second means for traversing the yarn axially of said spindle in a second direction, traversing of the yarn by said first and second means serving to distribute the yarn to form a yarn package, guide means operable to direct said first and second means in respective first paths as the yarn is traversed onto related first zones of said package and in respective second paths as the yarn is traversed onto related second zones of said package, at least a portion of said first path of said first means and at least a portion of said second path of said second means being in a common zone spaced from said package and moving in diverging paths within said zone, both of said paths being offset relative to the axis of said spindle.

13. The combination as set forth in claim 12 wherein said first and second means each comprises respective first and second endless spans. I

14. The combination as set forth in claim 13 including rotatable means for directing the paths of said first and second spans.

15. The combination as set forth in claim 14 wherein said rotatable means is operable to move said first and second spans in opposite directions.

16. The combination as set forth in claim 13 wherein each of said first and second spans includes at least one yarn engaging member thereon for movement therewith.

17. Strand-traversing mechanism comprising means for traversing a strand to and fro between opposite reversal ends of a strand traversal path and including, flexible belt means, guides carried by said belt means operable for receiving the strand from the oppositely moving guide at one of said reversal ends and retaining and moving the strand along said path toward the opposite reversal end and maintaining uniform controlled movement of the strand proximate the reversal ends while the strand is retained by the respective guide and releasing the strand at said opposite reversal end where a guide receives the strand, a delivering sprocket adjacent the reversal end where a guide releases the strand, a receiving sprocket adjacent the reversal end where a guide receives the strand, said flexible belt means carrying the guides at least partially about the receiving and delivering sprockets to support the guides in abutting relationship with the sprockets during transfer of the strand at the reversal ends, each of said guides having a surface for receiving the strand and moving the strand along said path between said reversal ends, each said surface having a free end portion, said flexible belt means mounting said guides with said free end portions extending across said strand traversal path as a guide approaches its delivering sprocket and for movement of said free end portions across said path as the respective guides move along said path and about their delivering sprocket for passage of the strand about said free end portions as the strand is released from the surface, said surface having a substantially straight portion adjacent said free end portion for guiding the strand between the reversal ends, said free end portion being shaped to maintain substantially constant velocity of the strand along the strand traversal path as the strand moves across said free end portion when the strand is released by the guide, and tensioning means for maintaining said strand constantly tensioned during transfer at said reversal ends.

is. Mechanism as set forth in claim ll'l in which each said guide includes means for retaining the strand proximate said surface as the guide receives the strand during transfer from a delivering sprocket.

l9. Mechanism as set forth in claim lib, in which the last said means comprises an abutment, said abutment leading said surface.

20. Mechanism as set forth in claim 19, in which said sprocket means are positioned for movement of said guides first toward said strand traversal path and then away from said strand traversal path, to provide said to and fro movement of said guides relative to said strand and to prevent uncontrolled movement of said guides intermediate said reversal ends, said guides being mounted for movement to and fro across the strand.

2ll. Mechanism as set forth in claim in which said belt means comprises separate belts, one for each of said guides, said belts being timing belts and said sprockets being timing belt sprockets.

22. Mechanism as set forth in claim 17 including means for receiving the advancing strand as it leaves the guide means and for providingsubstantial resistance to movement of the strand along the strand traversal path.

23. Mechanism as set forth in claim 117 in which the oppositely traveling guides pass each other during transfer of the strand and are as close to each other as is practicable.

24. Mechanism as set forth in claim 17 in which said tensioning means is operable for supporting said strand on a fluid cushion.

25. Mechanism as set forth in claim 17 in which said tensioning means is operable for preventing said fluctuations in strand tension.

26. Mechanism as set forth in claim R7 in which each said guide has a surface for receiving the strand and moving the strand along said path between said reversal ends, each said surface has a free end portion shaped for the passage of the strand thereacross at substantially constant velocity along said strand traversal path as the guide moves about its delivering sprocket, and the delivering sprockets mount the associated guides with said free end portions extending across said strand traversal path as the guide approaches its delivering sprocket and for movement of said free end portions across said path to release the strand as the guides move about their respective delivering sprockets.

27. Mechanism as set forth in claim 26 in which said surface has a substantially straight portion adjacent said free end portion for moving the strand when the strand is received from a delivering guide, and each said guide includes means for retaining the strand proximate said surface as the guide received the strand during transfer from a delivering guide, the last said means comprising an abutment, said abutment leading said surface, and said operating means positions said guide with said abutment spaced relative to said path to permit passage of the strand past the abutment upon release of the strand from the delivering guide and thereafter positions said abutment across said path to retain the strand between the abutment and the surface.

2b. Mechanism as set forth in claim 27 in which said operating means further comprises second sprocket means receiving said belt means intermediate said reversal ends and mounting said guides for movement to and fro across the strand, first toward said strand traversal path and then away from said strand traversal path.

29. Mechanism as set forth in claim 2% in which said belt means comprises separate timing belts, one for each of said guide means, and said sprockets are timing belt sprockets.

3t). Mechanism as set forth in claim 29 including means for receiving the advancing strand as it leaves the guides and for providing substantial resistance to movement of the strand along the strand traversal path.

3i. An improved belt traverse for strand material comprising a flexible endless belt, a strand guide element, and means for attaching said guide element to said belt comprising a generally U-shaped channel having one of its legs connected to said guide element to support the same, said channel snugly receiving the belt therein and extending around three sides of the belt, a clamping plate disposed on the fourth side of said belt opposite the base of said channel, and means for urging said plate toward said channel to compress said belt therebetween.

32. The belt traverse to claim 3ll wherein the other of said channel legs is provided at its end with a flange projecting toward said other leg and said clamping plate has an edge engaged beneath said flange.

33. The belt traverse of claim 31 wherein said last-named means is a screw adjustably connecting said plate and channel together.

34L An improved belt traverse for strand material comprising a flexible endless belt, a strand guide element, and means for attaching said guide element to said belt comprising cooperating clamping plates on opposite sides of said belt, said guide element being connected to one end of one of said plates to project outwardly of the belt, and means for urging the two plates together.

35. The belt traverse of claim 34 wherein said belt is provided with equally spaced teeth on one side thereof, one of which teeth is removed, and the clamping plate on the corresponding side has a length and thickness not exceeding the corresponding dimensions of the tooth and occupies the position of said tooth.

36. The belt traverse of claim 35 wherein the clamping plate connected to said guide element extends generally at right angles to said element and lies on the toothed side of said belt, and said other clamping plate has the end thereof opposite said guide element bent upwardly therefrom generally parallel to the element, said upstanding end having extensions thereon projecting to either side of the plate in the lengthwise direction of the belt, with their inner edges engaging the belt surface, whereby the guide element is braced against independent lengthwise rocking movement.

37. The belt traverse of claim 36 wherein said first clamping plate has an extension thereon reentrantly curved for engagement with the upstanding end of said other clamping plate.

38. The belt traverse of claim 37 wherein one end of said clamping plate is bent generally at right angles to the remainder of the plate, said angularly bent end having ears extending outwardly on both sides of the plate lengthwise of the belt with the adjacent edges of said ears in substantial abutment with the belt surface whereby said element is braced against independent lengthwise rocking movement.

Claims

1. A yarn-winding machine comprising, a rotatable spindle, yarnengaging means for traversing an advancing strand of yarn axially of said spindle to wind a package of yarn, and guide means for directing said yarn-engaging means in a first path as the yarn is traversed onto a first zone of said package, said guide means being operable to direct the yarn-engaging means in a second path diverging from said first path as the yarn is traversed onto a second zone of said package, said first and second paths being offset relative to the axis of said spindle.

9. The combination as set forth in claim 7 wherein the axes oF the respective first guides and the respective second guides are offset from each other in a plane parallel to the package axis.

10. The combination as set forth in claim 7 wherein the axes of the respective first guides and the respective second guides are offset relative to each other both in a plane perpendicular to the package axis and in a plane parallel to the package axis.

13. The combination as set forth in claim 12 wherein said first and second means each comprises respective first and second endless spans.

18. Mechanism as set forth in claim 17 in which each said guide includes means for retaining the strand proximate said surface as the guide receives the strand during transfer from a delivering sprocket.

19. Mechanism as set forth in claim 18, in which the last said means comprises an abutment, said abutment leading said surface.

21. Mechanism as set forth in claim 20 in which said belt means comprises separate belts, one for each of said guides, said belts being timing belts and said sprockets being timing belt sprockets.

22. Mechanism as set forth in claim 17 including means for receiving the advancing strand as it leaves the guide means and for providing substantial resistance to movement of the strand along the strand traversal path.

23. Mechanism as set forth in claim 17 in which the oppositely traveling guides pass each other during transfer of the strand and are as close to each other as is practicable.

25. Mechanism as set forth in claim 17 in which said tensioning means is operable for preventing fluctuations in strand tension.

26. Mechanism as set forth in claim 17 in which each said guide has a surface for receiving the strand and moving the strand along said path between said reversal ends, each said surface has a free end portion shaped for the passage of the strand thereacross at substantially constant velocity along said strand traversal path as the guide moves about its delivering sprocket, and the delivering sprockets mount the associated guides with said free end portions extending across said strand traversal path as the guide approaches its delivering sprocket and for movement of said free end portions across said path to release the strand as the guides move about their respective delivering sprockets.

28. Mechanism as set forth in claim 27 in which said operating means further comprises second sprocket means receiving said belt means intermediate said reversal ends and mounting said guides for movement to and fro across the strand, first toward said strand traversal path and then away from said strand traversal path.

29. Mechanism as set forth in claim 28 in which said belt means comprises separate timing belts, one for each of said guide means, and said sprockets are timing belt sprockets.

30. Mechanism as set forth in claim 29 including means for receiving the advancing strand as it leaves the guides and for providing substantial resistance to movement of the strand along the strand traversal path.

31. An improved belt traverse for strand material comprising a flexible endless belt, a strand guide element, and means for attaching said guide element to said belt comprising a generally U-shaped channel having one of its legs connected to said guide element to support the same, said channel snugly receiving the belt therein and extending around three sides of the belt, a clamping plate disposed on the fourth side of said belt opposite the base of said channel, and means for urging said plate toward said channel to compress said belt therebetween.

32. The belt traverse to claim 31 wherein the other of said channel legs is provided at its end with a flange projecting toward said other leg and said clamping plate has an edge engaged beneath said flange.

34. An improved belt traverse for strand material comprising a flexible endless belt, a strand guide element, and means for attaching said guide element to said belt comprising cooperating clamping plates on opposite sides of said belt, said guide element being connected to one end of one of said plates to project outwardly of the belt, and means for urging the two plates together.