US2791274A - Yarn processing - Google Patents

Description

May 7, 1957 J. T. RIVERS, JR

} YARN PROCESSING 3 Sheets-Sheet 1 Filed Sept. 4, 1 .3

INVENTOR JosephTRivergJrr ATTORNEY May 7, 1957 Filed Sept 4, 1953 J. T- RIVERS, JR

YARN PROCESSING 3 Shets-Sheet 2 r90- JosephT 1N VENTOR ATTORNEY y 7, 1957 J. T. RIVERS, JR 2,791,274

YARN PROCESSING Filed Sept. 4, 1953 3 Sheets-Sheet 3 152 F .14 m 153 $11 15, 13 w 1,, 133 143 1 4 1 '130 156 Joseph TRivngJr ATTORNEY INVENT OR .z ay I /7' 2,791,274 YARN rnocnssnro Joseph T. Rivers, Jr., West Chester, Pa., assignor to E. I. do Font tie Nemours and Company, Wilmington, De!., a corporation of Delaware Application September 4, 1953, Serial No. 378,465

2 Claims. (Cl. 164- 18) This invention relates to the forwarding of funicular structures and to division of the structures transversely into shorter funicular lengths, and particularly to rotary apparatus adapted to grip yarn and to forward it and adapted also to produce staple lengths of fiber from the yarn being forwarded.

Increasing rates of production and processing of synthetic yarns require methods and apparatus suited to highspeed operation. Product uniformity requires correspondingly close control of yarn speeds and tension. Rapid subdivision of yarns composed of continuous filaments, i. e., tow (the normal result of continuous spinning processes), into shorter lengths or staple introduces additional critical requirements.

A primary object of this invention is positive forwarding of yarn or the like at high speeds without slippage. Another object is production of staple fiber from yarn being forwarded at high speed. An object is construc tion of rotary forwarding apparatus having reciprocating gripping means to hold yarn being forwarded. A further object is provision of rotary apparatus with reciprocating shearing means to sever yarn. Other objects of this invention will be apparent from the discussion below and the accompanying diagrams.

Figure l is a side elevation of one form of apparatus constructed according to this invention. Figure 2 is an expanded section taken in a plane through the rotational axis of the roll of Figure 1 at its periphery between clamping stations. Figure 3 is a side elevation of a simple form of apparatus (partly in section) according to the invention. Figure 4 is a section of the apparatus of Figure 3 taken on line 44. Figure 5 is a cross section taken in a plane passing through a clamping station and through the axis of rotation of the roll of Figure 1 to show a region about the periphery. Figure 6 is a perspective view showing mainly the top and rear of the clamp and blade members of Figure 5 removed from the enclosing sleeve. Figure 7 is a section taken on line 7-7 of Figure 5. Figure 8 is a section of Figure 5 taken on line 8--8. Figure 9 is a view sequence of clamp and blade members shown in section, as in Figure 7, illustrating successive relative operating positions. Figure 10 is a perspective view of a modification of clamping and shearing assembly. Figure 11 is a perspective view of a further modification of clamping and shearing assembly. Figure 12 is a perspective view of still a further modification of clamping and shearing assembly. Figure 13 is a side elevation of a modification of actuating arrangement for the rods connecting to the clamping and shearing assemblies. Figure 14 is a side elevation" of a further modification of actuating arrangement for the connecting rods. Figure 15 is a side elevation of still a further modification of actuating arrangement for connecting rods.

According to this invention, a funicular structure contacts a rotating device tangentially and remains in contact with it during rotation through an appreciable angle. The structure may be a single filament or a bundle of 2,791,274 iPatentecl May 7, 1957 filaments (which may be of such great length as to be considered continuous), both of which are termed yarn in this discussion; or it may be any of essentially similar structures, such as rope, wire, and ribbon, whether unitary or assembled from pieces by braiding, weaving, spinning or otherwise. For verbal simplicity, this account assumes that the structure being processed is yarn, but the same considerations apply to the other structures mentioned. During contact with the surface of the rotating device, the yarn is held in clamps oriented parallel to the axis of rotation of the device so as to prevent the yarn from slipping about the surface. This gripping ensures, for the duration of the contact of the yarn with the surface, a positive advancing or drawingoff of the yarn equal to the speed of peripheral rotation of the device.

During the period of contact between the yarn and the rotating surface, the yarn may be subjected to enough additional transverse force to destroy the continuity of the yarn structure, particularly when the force is applied so as to prevent the yarn structure from yielding except by shearing. Application of such a force at spaced intervals along the rotational path permits the reduction of a long or continuous structure into shorter lengths. The new pieces are released from any remanent clamping force after the shearing and are allowed to leave the rotating surface. They may be collected by suitable means.

In a simple form, the rotating device includes a cylindrical roll, which may have a groove in its surface so as to define an arcuate path for the yarn to occupy while being forwarded. External views of suitable rolls appear in Figures 1 and 3. As shown in the first figure, axle 2 of roll 1 may be coupled directly to shaft 3 of motor 4 mounted on a suitable base 5 by appropriate means, such as bolts 6 through angle brackets 7 fastened to motor housing 8. Aflixed, as by bolts 9, to an extension 10 of the base near the opposite end or face of the roll is a support 11 for journals 12 carrying a second axle 13. At the end nearer the roll, this axle terminates in a flange 14 affixed to a wheel 15. In the arrangement shown in Figure 1, the wheel has a flange 16 on its opposite face, where a coupling 17 connects this second flange with the roll axle. Connecting rods 18 perpendicular to the face are spaced about the wheel near its periph ery, extending through ports (not visible there) cut in the roll parallel to its axle. Many features of the apparatus appearing in Figure 1 are shown in greater detail in the other drawings, so discussion of them is deferred until consideration of those features.

A general understanding of one form of the invention may be gained from consideration of Figure 3, whose main features are a grooved roll and two sets of connectingrods 31 arranged in pairs and penetrating the roll parallel to the axle 32 near its periphery. The rods are shown as identical except for a difference in length between those of the two different sets. The external ends 33 of the connecting rods of each set are hooked to ride as cam followers in appropriate cam channels cut into a wheel 34 carried by a frame 35 suitably mounted. The one-cycle cam wheel shown may be stationary on its axle or may rotate at a speed that is an integral multiple of the roll speed. The internal ends of one set of connecting rods constitute clamps and the ends of the other set are shear blades, one of each being accommodated in each port. The clamp-enclosing portion of each port terminates at the groove, while the adjacent blade-enclosing portion is extended across the groove for a short way as a hollow 29 into the other side of the roll. The cam channel 28 for the clamps is cut at a smaller angle than the channel 27 for the blades so that each clamp grips the yarn from a time just before the shearing by other adjacent blades begins until after it ends. The relative positions of the clamps and blades at various locations around the roll are visible in this drawing.

The relative positions of the clamps and blades are shown also in Figure 4, which presents an end view of the roll sectioned at the yarn groove but showing yarn 40 in place. Twelve clamping and shearing positions are shown around the wheel; for reference, they may be designated conveniently by the usual hours of the clock. A bundle of multi-filament yarns contacts the roll tangentially from the upper left, or about the 11 oclock, position, and proceeds clockwise around the roll for a half circle or so. At the 12 oclock position, clamp 41 is beginning to close. At the 1 oclock position, both clamp 42 and blade 43 are closing on the yarn. Clamp 44 has a firm grip on the yarn at the 2 oclock position, and blade 45 is about to sever the yarn. Shearing of the yarn occurs by the 3 oclock position as blade '46 becomes fully 'extended, clamp 47 being closed tightly on the yarn. At the 4 oclock position, blade 48 is beginning to retract, but clamp 49 is still closed. Both blade 50 and clamp 51 are retracting at the oclock position, and at the 6 oclock position, blade 52 is completely withdrawn and clamp 53 nearly so. Upon the release of clamp 54 in the 7 oclock position, the severed length of yarn 55 between the 7 and 6 oclock positions continues tangentially, leaving the roll completely. In the remaining positions, both the clamps and blades are completely retracted. If desired, a jet (not shown) may be positioned to force air between the roll and the released pieces of yarn to aid their removal and collection. The best timing for the clamping and shearing actions may vary from that illustrated, depending upon the speed of operation, characteristics of the material being processed, and the durability of the materials of construction; however, determination of optimum timing is only a matter of operative skill. The timing shown in Figures 3 and 4 was selected for its simplicity, as well as for its utility over a wide range of operating variables.

The clamps and blades are made of a long-wearing material, such as a suitable tool steel. They may be lubricated in a conventional manner, as by injection of oil through small ports (not shown) in the roll or by facing part of adjacent sliding surfaces with lubricantimpregnated metal. The roll itself may be made of any suitable material, such as iron or steel. The groove bottom may be especially treated to render it highly resistant to abrasion, or a removable insert (not shown) may be provided for the yarn to ride on in place of contacting the body of the roll.

Many refinements in the construction and'us'e of such apparatus are possible. Of course, the spacing of the shearing positions around the roll will determine the length of the resulting short pieces of yarn. Identical spacing between adjacent positions will be useful for production of uniform lengths, but non-uniform spacing may be employed to produce a blend of lengths, as may be desirable sometimes in the manufacture of staple fiber. The'length of cut may be varied by omitting the blades from some of the positions provided. The rapidity with which the severed lengths are produced will be inversely proportional to the spacing of the shearing positions and directlyproportional to the angular velocity of the roll. For example, at an angular rotation of 3600 revolutions per minute, a roll with a diameter of about 17 inches at the yarn groove has a groove perimeter of nearly 54 inches and a peripheralspeed of about 5400 yards per minute. Each position goes through one cycle with each rotation ofthe roll, so to produce individual lengths of approximately 2 /2 inches requires 22 shearing positions on the roll. This corresponds to almost 80,000 shearings per minute, not an excessive number as much higher rates are obtainable by employing greater speeds or closer spacing ofthe shearing positions. Rates of 100,000 per minute or more are useful, especially with high draw-otf speeds, which may reach or even exceed 10,000 yards per minute. Such high-speed operation is especially advantageous in methods of yarn manufacture utilizing drawing or stretching soon after extrusion of the fiber-forming material, eliminating intermediate storage of the product and separate winding and drawing steps.

In Figure 3, the shearing action occurs as the blade passes the extension of the gap between the clamp and the abutting internal wall of the roll, i. e., the yarn location, and enters the extra hollowed portion of the roll. Most of the Wear takes place between the contacting edge of the blade and the wall portion of the roll, at the corner between the end of the clamp-receiving region and the extra hollow. To minimize the effect of this wear, a somewhat dilferent design to permit removal of the shearing surfaces is useful. Simple and highly effective designs for accomplishing this are illustrated in detail in several of the drawings. Furthermore, it is convenient to fabricate a roll in two separate pieces as shown in Figure 2. One piece 21 is notched to provide one wall 22 and the entire bottom 23 of groove 20, while the other piece 24 (shown slightly separated in this expanded view) provides the opposite Wall 25 of the groove when clamped against the first piece. The roll in Figure 1 is so designed, and many of its internal features are shown in subsequent figures.

Figure 5 shows a section on a radial plane passing through a shearing position on roll 1 of Figure l. Visible are the two pieces 21 and 24 forming the roll, both of which are bored to receive a sleeve 70 holding clamping and shearing mechanism the one piece is also counterbored from the outside to receive a double nut 71, one end 69 of which screws about the externally threaded end of the sleeve, the other end 73 threading about a plug '74 abutting an end 75 of the stationary clamp. An enlargedportion 76 at the unthreaded end of the sleeve acts like a bolthead in cooperating with the nut to draw the two pieces of the roll tightly together about the sleeve. The right end of clamping and shearing assembly 60 extends out through this head-like portion of the sleeve. The clamping and shearing assembly comprises three main pieces: a stationary clamp 61, a movable clamp 62, and a blade 63, as well as two compression springs, one spring 64 being between the movable clamp and the blade and the other spring between the stationary clamp and the inside wall 66 of the sleeve. Threaded into a hollow in the external end of the ,blade at this location is a connecting rod 18 to wheel 15 that actuates the clamping and shearing assembly. The rod extends through a hollow bolt 77 inserted through the wheel parallel to its axis and'fastened by a retaining nut 78. The rod is welded to the head 79 of the bolt, which is at the far side of the wheel from the roll itself. Radial oiling'channel 56 in roll 24 communicates with groove 57 around sleeve where the sleeve surrounds the clamping and shearing mechanism. Two small feeder orifices 58 lead from groove 57 through the sleeve from its outermost extremity to its interior just above the top of the clamping mechanism. The reciprocation of the clamping and shearing pieces aids in circulating the lubricant. Two circular rings 59 set into the flange straddle groove 57 to confine the oil flow, which may be under pump pressure or merely centrifugal, mainly to the feeder orifices. The radial oiling channel communicates with a source of oil through appropriate axial passages (not shown) in the roll'or in'the axle itself.

The perspective'view of Figure 6 further illustrates clamping and shearing assembly 60, turned end for end (and rotated about its longitudinal axis approximately l'35) as compared with the'view in Figure 5. In this position, the spring recessed in the stationary clamp is hidden. Figure 7 shows the'assembly viewed in a tangential plane looking along ara'dius toward the roll axis, which amounts toa rotation of about the longitudinal axis of the assembly from the position in Figure 5. The

a ter-eve;

stationary clamp piece 61 isa doubly stepped rectangular parallelepiped formed like 'three rectangular solids of different sizes joined from largest to smallest with one long corner common to all three, adjacent sections having one entire face and two corners in common. The large end 75 of the stationary clamp may be somewhat convex, as shown in Figure 5, to ensure even contact with the plug, which by its degree of insertion in the sleeve adjusts the position of the stationary clamp. Located in a boring 82 in the forward face of the stationary clamp (taken with respect to rotation of the roll) is compression spring 65 seating at the bottom of the boring and pressing against the forward internal wall of the sleeve to force the stationary clamp into contact with blade 63, which slides along a common face of the two smaller sections of the clamp, with the blade in the trailing position. Sliding on only the smallest section of the stationary clamp is movable clamp 62. The clamping end 83 of the movable clamp faces clamping end 84 of the intermediate section of the stationary clamp, these two faces being substantially parallel to each other to ensure a good grip on the yarn between them. The other end of the movable clamp forms a solid L to fit in a cutout in the blade, and in the L end directly opposite the movable clamping face is a slight recess in which fits one end of compression spring 64. The other end of this spring fits into the body of the blade where the blade assumes the same cross section as the largest part of the stationary clamp. The shearing end 88 of the blade has a cross section equal to the difference between the largest and intermediate cross sections of the stationary clamp, sliding as it does along the intermediate section as well as along the smallest section. This end of the blade may be beveled so as to permit the yarn to bend gradually to one side and to prevent possible crushing of the yarn ends between the end of the blade and the stationary clamp. This provision is shown most clearly in Figures 6 and 9. A sectional end view taken from the groove toward the blade in the retracted position shows the orientation of the three elements described surrounded by the sleeve, as in Figure 8.

The relative positions of blade 63, stationary clamp 61, and movable clamp 62 appear in the sequence of three views in Figure 9. The connecting rod (not shown) is fully withdrawn to retract the blade completely at A, retracting the movable clamp also by contact at the cutout face 91 of the blade with the L end of the movable clamp and bringing both of these solid members free of the groove. The position of the stationary clamp is adjusted manually beforehand by setting the plug at the proper location in the sleeve nut to place clamping face 84 flush with wall 22 of the groove. A multi-filiment yarn bundle 92 is shown in the groove. The second of the three views shows the elements as the connecting rod forces the blade toward the groove; the movable clamp undergoes a similar motion by the compression of spring 64 linking it to the blade. As shown at B, when the movable clamp approaches the stationary clamp face sulficiently to grip the yarn, the spring is forced together while the blade continues to move across the path of the yarn. The yarn is severed by the action of the blade in coming flush with and slipping over the stationary clamp, as shown at C. Ensuing retraction of the blade withdraws both it and the movable clamp, freeing the severed ends of the yarn. Spring 64 surrounds guide rod 89, which is fixed at one end in the L end of the movable clamp so as to rest at the free end in passage 90 in the blade. Upon relative movement of the blade and the movable clamp, this rod slides in the passage, keeping the spring centered during compression. Such a unitary construction of clamping and shearing mechanism is self-synchronizing so that the yarn is always firmly held at the time of the severing action.

Other suitable clamping and shearing assemblies appear in Figures l0, l1 and 12. The assembly 100 of Figure differs from that discussed in detail above mainly in the shape'of the elements. "Stationary clamp 101 has auniform triangular cross-section, which slides over oblique face 102 of end section 103 of blade 104. Movable clamp 105, having a similar triangular cross section, also slides on the same face of the blade, being urged toward the stationary clamp by spring 106. Shearing edge 107 of the blade thus will sever yarn 108 at a moderate angle to the path of the yarn, producing a slightly tapered end. This assembly relies upon resistance of the coupling spring against extension in order to retract the movable clamp, as well as the compressing force to close it. The 'assembly 110 of Figure 11 differs further by having one clamping face 111 integral with the primary reciprocating member or movable clamp 112 and having the indirectly driven clamp member 113 also movable when the first clamp approaches it sufficiently to grip the yarn between the two clamping faces. Clamp 113 is loaded by spring 114 attached to a stationary blade member 115. Shearing occurs between the sliding junction of this face and end 116 of the stationary blade, along which the movable clamps slide. In this arrangement, yarn 117 is displaced transversely until the stationary blade is reached; proper compression in the spring causes the two movable .clamping faces to grip the yarn securely during this preliminary displacement. Figure 12, which is turned end for end as compared with the other perspective views of these assemblies, shows an assembly 120 somewhat like that of Figure 11 except that the cross sections of both movable clamps 121 and 122 flare outwardly (from the direction of the roll axis) and a centrifugal loading member 123 is added, designed to slide in a radial bore (not shown) of the roll and to force the cooperating shearing edges together. A combination compression-extension spring 124 connects the indirectly driven movable clamp 122 with stationary blade 125.

Of course, the clamping and shearing assemblies may be reciprocated by any suitable means. The simple cam wheel suggested in Figure 3 is operable, although with high rates of speed excessive wear may become a problem. The preferred design appears in Figure 1. The axle on which the wheel is mounted forms a slight fixed angle with the roll axle. This angle of skew depends upon the desired throw of the assemblies and the radius at which they operate, as an increase in either the radius or the angle will lengthen the throw. Ordinarily, an angle of about a degree or so will prove satisfactory. As the axles of both roll and wheel lie in the plane of Figure l, the full angle between them is visible in the drawing; exaggerated for clarity in the diagram, it is only about l.5, which is noticeable mainly in the variation produced in the visible length of the connecting rods at the top and bottom of the figure. An important feature of the construction is the lateral flexibility of the connecting rods, which must adapt themselves to a change in direction as the roll rotates. They may be made of any of a number of materials, such as rubber, polytetrafluoroethylene, or nylon, to mention only 'a few. Thin flexible metal rods or tubes could be employed, instead. Elasticity through the required angle of bend (twice the skew of the axle) and good abrasion resistance :are prime requisites for the connecting rods. If a coupling is used between the roll and wheel at the axles, it preferably is made of similar material. Of course, these flexible couplings could be replaced by universal or ball joints, if desired.

Other useful camming arrangements appear in Figures 13, 14 and 15. Figure 13 shows a cam apparatus that bears some slight resemblance to both of the arrangements already illustrated. It shows a skewed wheel 131 and a double-acting U-shaped cam follower 132 bridging the rim 133 of the wheel to reciprocate connecting rods 134 and associated parts (not shown) with respect to roll 135. The contact between the wheel and the ends of movable ears 136 on the ends of the U members may be sliding, or appropriate bearings may be inserted in either or both of these elements to convert to a rolling contact for reduction in wear. One solution of the wear problem present with cam operation appears in Figure 14, where the cam wheel 141 is slotted in one more or one fewer cycles than the number of shearing positions on roll 142. This effects a substantial reduction of the peripheral velocity of cam follower 143 around the wheel. For example, with '22 positions on the roll and 23 cycles on the wheel, the wheel may rotate at twenty-two twentythirds the speed of the roll while providing the same shearing frequency as a stationary wheel with one cam cycle would provide. In Figure 15, each connecting rod 151 terminates in a pivotable contact with an ear 152 of a V-shaped member 153 pivoted also at its apex 154 on an extension 155 from the adjacent roll face 156. The other car 157 of the V member pivotally contacts a rotary structure 158, which may be a spoke or the rim of a wheel, mounted "for free rotation on an axle 159 parallel to but offset from that of the roll. As the roll rotates, the V members swing back and forth to allow for the change in relative radius between the roll and the wheel. This reciprocates the accompanying rods. The V member may be replaced by cam and follower or gear and rack to attain the same action.

Many other modifications may be made in the apparatus described without departing from the inventive concept. Of course, it is clear that the direct drive may be replaced by a belt, chain, or gear drive or by a variablespeed mechanism. The roll design may differ. Various connecting linkages and actuating means for them may be devised. The design of the clamping and shearing members may be altered. However, the features peculiar to this invention provide pronounced advantages in a great variety of forms. The yarn-gripping action of the multiple clamps maintains the yarn travel commensurate with the roll peripheral movement. When shearing is employed, the yarn is held against lengthwise motion during severing, producing a clean sharp discontinuity. When staple is produced in this way, the ends are even and regular, much more desirable than the straggly cut produced by knife-like cutting apparatus. No bits of fuzz break or split off to clog the apparatus. Many other advantages will be apparent upon a thorough consideration of the invention.

What is claimed:

1. Apparatus comprising a rotatable circular cylinder having a peripheral surface grooved to accommodate a funicular structure, a clamping and shearing mechanism slidcably mounted in each of a plurality of passages intersecting the grooved region of the surface parallel to the cylinder axis, an equal plurality of connecting rods, each rod joining a reciprocatable element of one of the mechanisms to a cam wheel for closing and opening a clamp portion of the mechanism and for forcing a blade portion of the mechanism back and forth across the grooved region of the surface, said cam wheel being rotatably mounted on an axis slightly inclined toward the cylinder axis and lying in the same plane.

2. The apparatus of claim 1 in which the cam wheel axis forms an angle of about 179 with the cylinder axis.

References Cited in the file of this patent UNITED STATES PATENTS 370,672 Bacon Sept. 27, 1887 947,724 Wood Jan. 25, 1910 1,374,200 Grondahl Apr. 12, 1921 2,017,184 Riess et al. Oct. 15, 1935 2,205,036 Hamel June 18, 1940 2,221,022 Ellis Nov. 12, 1940 2,664,160 Speakman Dec. 29, 1953 FOREIGN PATENTS 712,452 Germany Oct. 20, 1941 497,746 Belgium Dec. 16, 1950

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