AU2797601A - Rapid fabric forming - Google Patents

Description

P/00/011 Regulation 3.2

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A DIVISIONAL PATENT

ORIGINAL

TO BE COMPLETED BY APPLICANT 9* 9 Name of Applicant: E. I. DU PONT DE NEMOURS AND COMPANY S Actual Inventors: Peter Popper, William Charles Walker, Albert S Tam, Paul Wesley Yngve, James K Odle, George Yeaman Thompson Jr 9 Address for Service: CALLINAN LAWRIE, 711 High Street, Kew, Victoria 3101, Australia Invention Title: RAPID FABRIC FORMING The following statement is a full description of this invention, including the best method of performing it known to me:- 14/02/01,ckl 1876fcbl 4.divfront -2- FIELD OF THE INVENTION The invention teaches an apparatus to rapidly form a flat or shaped fabric consisting of groups of yarn densely covering an area.

This application is a divisional of application 49845/97, the disclosures of which are deemed to be incorporated herein by reference.

TECHNICAL BACKGROUND Textile fabric is often formed from strands, or filaments, of yarn by weaving or knitting or the like to hold the strands together. Processes of weaving and knitting where strands are guided over and under adjacent strands are slow and do not permit much variety in forming fabric shapes. In a loom for weaving fabrics, the weft yarns are added one at a time. These processes typically result in flat or cylindrical fabrics. There is a need for a process that, in addition to making flat or cylindrical fabrics, permits more variety in forming fabrics with random three dimensional shapes, for instance, that would permit forming an article of clothing, such as a shirt, without having to cut pieces of fabric and seam them together. The cutting of fabric into irregularly shaped patterns wastes a lot of fabric, plus cutting and sewing add steps over forming the fabric article directly. The same problem is present in making flexible engineered shapes such as automotive air bags, sail boat sails, industrial filter bags, or the like. In these cases, the need for seams to form three dimensional shapes presents problems with structural strength and/or permeability so the seams must be carefully made.

There is a need for a way to rapidly form a flexible fabric from strands of yarn; there is a need for a way to rapidly form a three dimensional, flexible, fabric article without cutting a flat fabric and seaming.

There is also a problem making complex shapes for composite structures that may be impregnated with a hardenable resin. It is sometimes desired to lay down the filaments in a three dimensional shape before adding the resin or during resin addition. Present means for doing so involve complex forms with -3retractable support means to hold the filaments in place before the resin hardens.

There is a need for a simpler way to preform these fabric shapes without seams.

Such seams would compromise the strength of the composite structure.

A series of Oswald patents 4,600,456; U.S. 4,830,781; and U.S.

4,838,966) lay down a pattern of partially vulcanised rubber coated strips, or cords to make a loop of preformed reinforcing belt for a vehicle tire. The strips or cords are stuck together wherever they touch to make a relatively stiff structure. The cords are laid in a "zig-zag repeating pattern with succeeding lengths of the strips being displaced from each other. The cord lengths are interleaved with lengths of cords disposed at an opposite angle... This interleaving relationship results in a woven structure". The stickiness of the partially vulcanised rubber apparently holds the cords in place to a forming surface and to each other until the belt is assembled with other elements of the tire and molded under heat and pressure to form a completed tire.

The process practiced by Oswald and others uses one or a few cords that are traversed back and forth across the belt numerous times to complete one circumference. This is believed to result in a multilayered structure where the cords in any one layer are sparsely arrayed, but they do not completely cover the belt area. It is only after repeated zig-zag passes over the belt area that the area becomes sparsely covered with cord. Due to the repeated zig-zag passes of only a few cords, it is believed that within any one layer there are cords layed down in two different directions that do not cross one another. Cords that cross one another would be in different layers. These structural features of the reinforcing belts are symptomatic of a process that lays down only a few cords at a time and must make repeated passes over the belt area to get coverage of the area.

There is a need for a simple non-weaving process that can make fabric structures by laying down many yarns simultaneously over a fabric area to sparsely cover it rapidly, and to stack several of such sparse yarn coverages to densely cover the area.

"1 1 -4- SUMMARY OF THE INVENTION The invention concerns a fabric forming device for forming a fabric structure from a plurality of yarns, comprising: an endless loop conveyor having a travelling support surface for supporting the fabric structure being formed, the surface having opposed edges parallel to the direction of travel and holders along each edge to temporarily hold the yarn to resist lateral motion of the yarn, the conveyor having a controllable motor for propelling the travelling support; a plurality of guide bars adapted for movement across the surface from edge to edge, each bar containing a plurality of guides for repeatedly guiding a plurality of yarns form the holders along one edge to the holders along the opposed edge and back to the one edge, the guide bars having a controllable actuator for propelling the bars back and forth across the support surface; 15 a plurality of bonders arranged across the support surface between the support surface edges and beyond the last guide bar in the direction of travel of the surface, the bonders adapted to bond one yarn to another yarn where they cross; a controller for coordinating the controllable motor; and actuators to continuously form a fabric structure on the support surface of the conveyor.

A further embodiment is a yarn dispensing device for laying down yarn accurately on a compound curvature, when using a mechanical actuator, comprising the following elements: a mechanical guide actuating means; a yarn guide comprising a frame that supports a hollow shaft through which yarn can pass; a slide, attached to the yarn guide, and also attached to the guide actuating means; a block mounted on said hollow shaft which supports a plurality of flexible springs that intersect at a common point; at the point of intersection of the springs is a hollow tip with a hemispherical end through which the yarn can pass, said springs permitting motion of the tip in an axial or angular direction, the rotation of said shaft allowing the tip to roll over any surface it contacts while it is also free to deflect axially and angularly, so as to accurately place a yarn on the surface while the yarn passes through a hole in the hollow shaft and a hole in the hollow tip.

BRIEF DESCRIPTION OF THE FIGURES Figures 1 to 5 illustrate the invention of parent application 49845/97.

Figure 6 shows an apparatus for continuously forming a two dimensional biaxial yarn fabric with the yarns oriented at an acute angle to the machine direction, and a fabric thus formed.

Figure 7 is an enlarged view of a portion of the fabric of Figure 6.

Figures 8A-B show another apparatus for continuously forming a two dimensional biaxial yarn fabric similar to that of Figure 7.

Figure 9 is an enlarged view of a portion of a fabric formed by the apparatus of Figure 8.

**Figures 10 A-B show a table apparatus for making a single batch of two 20 dimensional or three dimensional fabric structure and a sample of a piece of three dimensional biaxial fabric structure.

Figure 11 A shows a mandrel apparatus for making a single batch of twodimensional or three dimensional fabric structure.

~Figure 11B shows a mandrel apparatus for making a tubular batch of fabric 25 structure.

Figure 11 C shows a flattened view of a tubular fabric structure made on the apparatus of Figure 11 B.

Figure 11 D shows a special device for laying down yarn.

Figure 12 shows another mandrel apparatus for making a single batch of three dimensional fabric structure.

-6- Figure 13 shows another apparatus for continuously forming a two dimensional biaxial fabric structure with the yarns oriented at 0 degrees and degrees to the machine direction.

Figure 14 shows a diagrammatic view of a cell of fabric.

Figure 15 shows a generalised yarn dispensing system for a shaped mandrel.

Figure 16A-16D show the general orientation of a single subgroup of a single group onto the shape of Figure Figures 17A-17D show the orientation of a single subgroup of three groups onto the shape of Figure Figures 1 8A-18E show the orientation of successive subgroups of each group being deposited to densely cover the shape of Figure 15 and form the shaped fabric.

Figures 1 9A-19E show a system for making a shirt fabric.

Figure 20 shows a special device for laying down yarn on mandrels with compound curves.

S"DETAILED DESCRIPTION :""Figures 1 to 5 are described in parent application 49845/97.

In Figure 6, is shown an apparatus for continuously forming a biaxial fabric 20 structure with a basic cells similar to those of Figures 1E and 2A. The apparatus consists of an elongated yarn support surface, such as a flat perforated belt 91, driven by motor 107, having an array of pins, such as pin 93, along one edge 94 and a parallel array of pins, such as pin 96 along the opposite edge 98 of belt 91 for positively holding yarns against the forces of yarn reversal. Beneath the belt 25 is arranged a vacuum plenum 97 attached to a source of vacuum 99 for holding the yarn in place on belt 91. Shown along edge 98 are a plurality of yarn guide blocks 100, 102, 104, and 106 that are each mounted on guide means, such as guides 101 and 103, and each having drive means, such as actuator 105 for block 100, for traversing across belt 91 from one edge 98 to an opposed edge 94. Each yarn guide block has a plurality of yarn guides, such as guide 173 in block 100, for guiding a yarn accurately onto the belt, such as yarn 111 coming off of yarn supply package 113. Dashed outlines 100', 102', 104' and 106' at edge 94 show the position the blocks would take after traversing belt 91. A plurality of ultrasonic horns, such as horn 108, at location 110 are positioned across the belt 91 to act on yarn laid thereon to fusion bond the overlapping yarns to one another at spaced positions in a deposited fabric. The belt and a rigid support 109 underneath act as the ultrasonic anvil to couple the energy through the yarn. As soon as the yarn cools from the ultrasonic bonding, the fabric structure can be stripped off the pins or hooks along the edge of the belt and the belt can be recirculated while the fabric is wound in a roll on a core (not shown). The winding tension for the fabric would be controlled to avoid distortion of the fabric along the direction of the belt which is along the fabric diagonal (bias) and along the axis of the bond path.

A representation of a two-group, biaxial, deposited fabric 112 is shown on the belt. The representation shows the pattern of yarn laid down as the process S starts up and the belt moves from right to left in the direction of arrow 114 as the blocks move substantially perpendicularly across the belt together from edge 98 to edge 94 in a manner coordinated with the belt motion along the belt S* elongated axis; and continue back and forth as represented by arrows 116.

20 What is shown is what was produced at start-up and then was stopped and the S belt backed up to align the start pattern with the guide blocks. For a true representation, block 100 (and the other blocks) would be shown shifted to the right in the figure to a location just beyond block 106. At the left end 118 of fabric 112 the top subgroups of yarn are laid down by themselves, since at start- 25 up none of the other subgroups are in place yet. At the right end 120 of the fabric 112, all subgroups are in place for a fully formed fabric by position 122 and the fabric will thereafter be continuously fully formed as the belt and blocks continue moving as described. The speed of the belt and the speed of the blocks are controlled and coordinated by a controller 115 communicating with motor 107 and the actuator for each block, such as actuator 105. This ensures that -8the yarn passing through the guide blocks and laying on the belt forms a straight path at a 45 degree angle with the centerline and edge of the belt so there is a first group of yarn at 45 degrees as at 119 and a second group of yarn at degrees as at 121. By varying the controlled motions, other angles of laydown and curved paths are also possible. The first and second (lower) subgroups of yarn are laid down by block 106, the third and fourth (middle) subgroups of yarn are laid down by block 104, the fifth and sixth (middle) subgroups of yarn are laid down by block 102, and the seventh and eighth (upper) subgroups of yarn are laid down by block 100. A given yarn across the fabric may alternate between subgroups in the cells going back and forth across the fabric. In this example, the belt is moving and the blocks move only back and forth across the belt and the belt moves continuously from right to left. The same pattern can be generated if the belt is considered stationary and unusually long, and the blocks move back and forth diagonally at 45 degrees along the belt from left to right.

The pattern of over and under yarns varies in the fabric as evidenced by cells 124, 126, and 128. Figure 7 shows this portion of fabric 112 enlarged for discussion. The yarns are shown slightly spaced apart in each group for clarity.

In Figure 7, yarn 130 is the eighth subgroup top yarn in cells 124 and 126, but is S"the seventh subgroup yarn in cell 128. Likewise, yarn 132 is the sixth subgroup yarn in cells 124 and 126, but the fifth subgroup yarn in cell 128. Similar changes occur in the remaining subgroups. This deviation from a perfectly regular pattern within a fabric, unlike the pattern in Figures 1 E and 2A, does not affect the structural integrity of the fabric and is an example of some acceptable variations in the patterns of the invention. The adjacent cells 134, 136, and 138 are all identical and are the same as the cells of Figures 1E and 2A. Each yarn has a subgroup assignment and a position assignment in a cell. However, both the subgroup assignment and position assignment may vary from cell to cell in a given fabric structure, or they may remain constant, and in both cases still follow the basic rules for practicing the invention which are: -9a plurality of substantially parallel yarns in a group are arranged to densely cover an area with the yarns of one group arranged to cross the yarns of another group; each group is comprised of a plurality of subgroups, with each subgroup having a plurality of yarns sparsely arranged; the plurality of yarns in one subgroup of one group are offset from the plurality of yarns in the other subgroups of the same group; the yarns of the top subgroup and bottom subgroup are connected to each other at spaced locations either directly, or indirectly through the yarns in the other subgroups.

The top to bottom bond point for cell 124 is at 140; the bond point for cell 126 is at 142; the bond point for cell 128 is at 144. For a partial cell 146 at the edge of the fabric, the bond point is at 148. All these bond points would be covered by ultrasonic paths aligned with the arrows 150 at the left end of Figure 7.

Four yarns in each guide are sufficient to cover the belt for a four-yarn-cellspace fabric at the width shown and for a 45 degree pattern. In Figure 6, the space covered by one yarn, such as yarn 152, going from belt side 94 over to belt side 98 and back across the belt 91 takes up a distance along the belt as shown at 154. Four yarns, such as yarns 152, 156, 158, and 160 in guide 100, fill this space for subgroups 8 and 7. If a wider belt were used where the opposite edge 98 was at 162, the space covered by yarn 152 going back and forth across belt 91 would take up a distance along the belt as shown at 164.

This would require additional yarns 166, 168, 170, and 172 to fill this space for 25 subgroups 7 and 8. Guide 100 would have to be extended to hold 8 yarns instead of only 4 for this wider fabric, and block 102 would have to be shifted along the length of the belt 91 to make room for the larger block 100. Block 102 and the other blocks 104 and 106 would be extended and shifted similarly. The first yarn guide hole 171 in block 102 is shown spaced from the last yarn guide hole 173 in block 100 by a distance 175 of one cell diagonal plus one yarn position diagonal to lay down the subgroup 5 and 6 yarns in offset positions from the subgroup 7 and 8 yarns laid down by block 100. This spacing is similar for the succeeding guide blocks along the side of belt 91. This spacing may be less or more by units of a cell diagonal depending on how much room is needed for the guide blocks.

This spacing of guide blocks and coordinated motion between the blocks and the belt results in the 45 degree diagonal pattern of yarn wherein the positions of each of the diagonal yarns are adjacent the other yarns (rather than overlapping them) to thereby densely cover the yarn support surface on the belt with the yarns. If a more dense, thicker structure is desired, additional guide blocks may be employed and another dense structure built up on top of the first one to make a layered structure. In general terms, the process just described for forming an interlaced fabric structure comprises: providing an elongated fabric support surface having an elongated axis and opposed lateral edges parallel to the axis, and arranging the surface adjacent a plurality of yarn guide blocks arranged along opposed lateral edges of the elongated surface; providing a plurality of guides on said guide block, each guide adapted to guide a yarn from a yarn source to the support surface; engaging the yarns at one edge of said support surface; providing relative motion between the support surface and each of the plurality of guide blocks so that the guide blocks deposit yarn from the e guides onto the surface in a first diagonal direction relative to the edge of the II S surface and in a predetermined direction along the support surface; 25 engaging the yarns at an opposed edge of said support surface; reversing the relative motion of the guide blocks and support surface so that the guide blocks deposit yarn from the guides onto the surface in a second diagonal direction relative to the edge of the surface and in said predetermined direction; -11arranging said guide blocks and guides and arranging said relative motion so that when said yarns from said blocks are deposited on said surface, the diagonal positions of each of said yarn are offset from the other yarns to thereby densely cover the support surface with said yarns in one cycle of relative motion from one edge to the opposite edge and back to the one edge.

With the arrangement shown with separate guide blocks, the position of subgroup yarns in the cell space can be varied by displacing the blocks along the length of the belt 91. With a space between the guide blocks and the manner of laying down yarns to form a fabric, it is possible to add materials between the subgroups of yarns within a fabric structure. For instance, a roll of film 117 could be arranged to continuously feed film between blocks 104 and 106, around a guide 119, and onto the fabric 112 between the subgroups of yarn laid down by block 106 (subgroups 1 and 2) and block 104 (subgroups 3 and In another instance, machine direction yarns 121 and 1 23 could be arranged to continuously feed yarn between blocks 102 and 104, through guides 125 and 127 respectively, and onto the fabric 112 between the subgroups of yarn laid down by block 104 (subgroups 3 and 4) and block 102 (subgroups 5 and 6).

Such insertions of material between subgroups is a unique capability of the fabric of the invention. In the case illustrated, the addition of the film and machine 20 direction yarns can reduce the deflection of the bias fabric in the machine direction or can achieve other special purposes. Other materials, such as nonwoven fabrics, wires, elastomeric fabrics or yarns, webs of natural or S" synthetic materials, scrims, etc., can be inserted.

oleo There is another way of using guide blocks to lay yarn down continuously 25 to form a fabric on a belt. The blocks could be arranged in alternate locations o:o. along the edge of belt 91 and be arranged to travel in opposite directions across the belt as the belt is moving as shown in Figures 8A and 8B. In Figure 8A, the blocks 100 and 104 are arranged along edge 94 of belt 91 and blocks 102 and 106 are arranged along edge 98. As the belt 91 moves from right to left as seen going from Figures 8A to 8B, the blocks cross the belt to the opposite side, -12thereby laying yarn down on the belt in a diagonal path. Repeated operation of the blocks back and forth as the belt continues to run will produce a pattern such as seen in enlarged fabric 174 of Figure 9. This pattern is slightly different from the fabric 112 of Figures 6 and 7. Looking at cells 176, 178, and 180, cells 176 and 178 are five subgroup cells while cell 180 is an eight subgroup cell. In cell 176, yarn 181 is in subgroup 5; yarns 182 and 184 are in the same subgroup, subgroup 4; yarns 186 and 188 are both in subgroup 3; yarns 190 and 192 are both in subgroup 2 and yarn 194 is in subgroup 1. Looking at cell 180, yarn 181 is in subgroup 7; yarn 186 is in subgroup 5; yarn 188 is in subgroup 3 and yarn 194 is in subgroup 1. Cell 180 has the same arrangement as the basic cell of Figures 1E and 2A. In order to form proper bond points form the top subgroup to the non-intersecting bottom subgroup 1 in cell 176, there must be a bond point 196 between yarn 181 of group 5 and yarn 182 of group 4 plus a bond point 198 between yarn 182 and yarn 194 of group 1. With the ultrasonic bonding paths as shown by the arrows at 200, there will be an additional bond point 202 between yarn 181 of subgroup 5 and yarn 192 of subgroup 2 and a bond point 204 between yarn 192 and yarn 194 of subgroup 1. Through a chain of bond points in cell 176, the top subgroup 5 is connected to the bottom o subgroup 1 even though the top and bottom subgroups don't cross one another.

20 The arrangement of ultrasonic bond paths to achieve proper spaced bonds for the fabric 112 of Figures 6 and 7 is different from the bond paths for the fabric 174 of Figure 9.

Figure 10A shows another apparatus for producing two dimensional oo o fabrics of the invention. It is suitable for making a batch fabric instead of a 25 continuous fabric. It is a simpler apparatus than that of Figure 6. A single guide jblock 206 is oscillated back and forth by actuator 207 over a table 208 that also oscillates back and forth by actuator 209 in a direction at right angles to the direction of oscillation of block 206. Parallel rows of pins 210 and 212 hold the yarn at the reversals. Vacuum may also be applied to the plate if desired. The block and table make numerous cycles back and forth in a manner coordinated 13with each other to produce dense groups of yarn crossing one another. A single ultrasonic bonding horn 211 is then repeatedly passed over the fabric in paths parallel to the oscillation direction of table 208 to make spaced bond paths to connect the top and bottom subgroups of yarns together. The fabric is then peeled off the edge pins 210, 212. By adding motion to the guide 206 in a vertical direction by actuator 205, a three dimensional fabric could be made over a three dimensional form 203 mounted on table 208. Figure 10 OB shows the curved yarn paths in a fabric 213 that may be employed to cover a three dimensional form.

Figure 11A shows another apparatus for producing two dimensional batches of fabric structure. It is similar to the apparatus of Figure 10 except instead of laying yarn down on a table, the yarn is placed on a mandrel 214 by a guide block 216. Instead of the guide block 216 oscillating back and forth as in Figure 10, the guide block 216 is stationary and the mandrel 214 oscillates in a rotary motion by motor 215 as indicated by arrow 217 at the same time the table 208' moves the mandrel past the guide block by actuator 209'. A single row of pins 218 holds the yarn between reversals in both directions as the mandrel rotates. The result is a fabric having a cylindrical tubular shape during fabrication. After all yarns are laid down, a single ultrasonic horn 219 repeatedly follows an axial path along the mandrel at different circumferential locations over the fabric as it is oscillated back and forth via the table and mandrel. This results in parallel bond paths to connect the top and bottom groups together.

Alternatively, the horn could follow a circumferential path at different axial locations along the mandrel. When peeled off pins 218, the result is a flat fabric.

25 This fabrication on a cylindrical mandrel has an advantage over the flat plate of Figure 10 A in that yarn tension can be used to hold the yarns securely against the mandrel.

Figure 11B shows an apparatus similar to that in Figure 11A except the mandrel 214 would rotate continuously in one direction to make a cylindrical batch of fabric. In Figure 11B, a rotating mandrel 220 is mounted on moveable -14table 208" oscillated by actuator 209". A circular yarn guide support 222 holds a plurality of guides, such as yarn guide 224, that are spaced apart around the circumference of the mandrel 220. Support 222 is held stationary relative to the mandrel and table. A yarn strand, such as strand 226 from stationary package 228, is fed through each guide, such as 224, and is secured to end 230 of the mandrel where the support and mandrel are aligned before the mandrel starts to rotate and the table starts to move. Since the yarn packages are stationary, the yarn can be supplied endlessly using a resupply package (not shown) and yarn transfer tails on the packages. The mandrel 220 has a plurality of rings 232 and 234 of closely spaced pins near the ends 230 and 236, respectively, of the mandrel as shown. These engage the yarn at the ends of the traverse when the table reverses direction. At the end of each traverse as the yarn engages the pin rings, the table stops moving and the mandrel is moved through a few degrees of rotation to make sure the yarn is firmly engaged by the pins before the table reverses direction. The mandrel may be moved precisely by a stepping motor, such as motor 238. The yarn must also align with the desired offset position of the cell before laying down next to an adjacent yarn.

The yarn laydown pattern and the motion of the table and mandrel will be discussed further referring to Figure 11C which is an imaginary view of the 20 mandrel as if it were flattened out into a two dimensional form. At the left of the figure is mandrel end 236 and pin ring 234, and at the right of the figure is mandrel end 230 and pin ring 232. The dashed lines in the figure trace the yarn o paths on the back side of the flattened mandrel; the solid lines trace the yarn paths on the front side. The yarns illustrated are only those that are seen to start 25 on the front side of the figure at points 240, 242, 244, and 246; and of these; only the yarn starting at point 240 has its path traced throughout one complete laydown. These start points are those where the yarn is laid down by guides such as guide 224 in support 222. Four other yarns from support 222 would be tracing out similar paths starting on the back side of the flattened mandrel at the same spacing as the yarns shown on the front side. These points represent the first yarn position 0/4 of four possible positions for a first group in a cell space for the fabric. Yarn at point 240 follows path 248 as mandrel 220 rotates and translates relative to yarn guide support 222; while yarns at points 242, 244, and 246 follow paths 250, 252, and 254, respectively. Tracing path 248 for laying down yarn in a first group, path 248 passes to the back side of the flattened mandrel at 256 and returns to the front side at 258 and reaches the ring of pins 232 at 260. Similarly, another first group yarn from point 242 would reach the ring 232 at point 262; yarn from point 244 would reach the ring 232 at point 264; and yarn from point 246 would reach the ring 232 at point 266.

Assuming the yarn is instantly engaged by the pin ring 232, the mandrel rotation continued, and the mandrel translation reversed immediately, the yarn path 248' would start back along the mandrel from point 260 to lay down yarn in the second group. If this ideal situation did not exist, the translation of the mandrel would stop while the mandrel rotation continued for a few degrees to anchor the yarn in the pins. The points at the right end 230 of the mandrel represent the first yarn position 0/4 for a second group in a cell space for the fabric. Yarn path 248' passes to the back side of the flattened mandrel at 268 and returns to the front side at 270, and reaches the ring of pins 234 at point S 272. It now must be decided what pattern of yarn positions are desired in the 20 fabric. Assuming the next yarn position desired is the 1/4 position, and the mandrel will continue rotating in the same direction, the yarn landing at position 272 wants to be in position 274 before reversing the translation of the mandrel.

The translation of the mandrel will stop when the yarn reaches point 272 and will e dwell there while the mandrel rotates a few degrees until the yarn reaches point 25 274; and the translation will then reverse and the yarn will follow path 248".

This will cause the yarn to land in the right pin ring 232 at point 276 which is also in the 1/4 position of the cell space. If this is the desired pattern for the second group cell space, the mandrel translation can immediately reverse and the yarn will return along path 248". If it is desired to change the yarn position for the cell, the translation of the mandrel can stop and the mandrel can continue -16rotating for a few degrees until the yarn is in the desired position in the cell space, and then the translation reverses and the yarn follows on a new path.

The yarn pattern in a cell can then be different for the first group yarns and the second group yarns. This pattern will continue until the yarn point 240 lands back at pin ring 234 at position 278. At that point all the yarn positions for the cell space are occupied by subgroups of yarns and the cylindrical batch of fabric structure is ready for bonding.

An ultrasonic bonding horn (not shown, but similar to horn 219 in Figure 11) can make repeated passes along the axis of the mandrel by translating the mandrel without rotation under the stationary horn and rotating the mandrel through several degrees at the end of each pass. Alternatively, the bonding can be along circumferential paths. After bonding, the pin rings may be removed (by retracting or other means) and the fabric pushed off the mandrel. Alternatively, one end of the fabric may be cut at one pin ring and only the opposite pin ring removed. By pushing the fabric, it will expand, since the fabric is oriented on a bias relative to the mandrel axis, so it will be easy to slide the fabric off the mandrel. In general terms, the process just described for forming an interlaced °fabric structure comprises: providing an elongated fabric support surface on a rotatable 20 mandrel having a rotational axis and opposed lateral ends substantially perpendicular to said axis, and orienting the surface adjacent a circumferential yarn guide ring substantially perpendicular to said axis, the ring arranged adjacent a lateral end of the fabric support surface; 25 providing a plurality of guides on said guide ring, each guide adapted to guide a yarn from a yarn source to the support surface, the guides equally spaced to deposit yarn at equal intervals around the mandrel circumference; engaging the yarns at one end of said support surface; -17providing relative motion between the support surface and the guide ring so that the ring deposits yarn from the guides onto the surface in a first diagonal direction relative to the ends of the surface from one end to the opposed end and in a predetermined rotational direction along the support surface thereby sparsely covering the fabric area on the mandrel surface with yarns in said first direction; engaging the yarns at an opposed end of said support surface; reversing the relative motion of the guide ring and support surface so that the guide ring deposits yarn from the guides onto the surface in a second diagonal direction relative to the ends of the surface from said opposed end to said one end and in said predetermined rotational direction along the support surface thereby sparsely covering the fabric area on the mandrel surface with yarns in said second direction; arranging said guide ring and guides and arranging said relative motion so that when the yarns from said guides on the guide ring are subsequently deposited on said surface, the diagonal positions of subsequently deposited yarns are offset from previously deposited yarns in each first and second diagonal direction to thereby densely cover the support surface with said yarns after repeated cycles of relative motion from said one end to the opposed end and back to said one end.

In some cases, it is desired to use the same circular guide support 222 ,ooQ (Figure 11 B) for structures having different numbers of yarns per cell so a different guide support does not need to be installed for routine changes in yarn denier or the like. One way to accomplish this flexibility is to use a special 25 laydown pattern for yarns as discussed above referring to the split cell/single step process which would work well with this apparatus to make cells that would appear to have, and would perform as if there were, fewer numbers of yarns in each cell.

Another possibility is a method of operating the mandrel motor 238 and table actuator 209" to apply a multiple pass of yarns from guide support 222 to -18make actual changes in the number of yarns per sublayer in the structure. For instance, to double the number of yarns per sublayer, the yarns, such as yarns 226 and 226', could be layed down in a path designated by dashed lines 227 and which would add one yarn between the original yarns laid down by the guide. This would be accomplished as follows: a. rotate the mandrel in a clockwise direction as designated by arrow 221, and translate the mandrel past the guide support 222 as shown so that a sparse sublayer of yarn, such as a zero degree sublayer formed of yarns such as yarn 226 and 226', is layed down on the mandrel from pin ring 232 to pin ring 234; b. stop the translation and rotate the mandrel further by one half the distance between the yarn guides 224; c. reverse the rotation of the mandrel to rotate counter-clockwise and translate the mandrel past the guide support 222 so that the yarn, such as 15 yarn 226 and 226' is layed down on the mandrel from pin ring 234 to 232 and between the solid line yarns to add yarns to the sparse zero degree sublayer; eog.

d. stop the mandrel translation and continue the counter-clockwise rotation by a distance to place a yarn guide 224 in position for the next sublayer, such as a ninety degree sublayer; e. continue the counter-clockwise rotation and translate the mandrel see*: past the guide support 222 so that a sparse sublayer of yarn, oriented in a ninety degree sublayer formed of yarns such as yarn 226 and 226', is layed down on the mandrel from pin ring 232 to pin ring 234; olo°•. f. stop the translation and rotate the mandrel further in a counterclockwise direction by one half the distance between the yarn guides 224; g. reverse the rotation of the mandrel to rotate clockwise and 0 translate the mandrel past the guide support 222 so that the yarn, such as yarn 226 and 226', is layed down on the'mandrel from pin ring 234 to 232 and between the just-layed-down ninety degree sublayer yarns to add yarns to the sparse ninety degree sublayer; -19h. stop the mandrel translation and continue the clockwise rotation by a distance to place a yarn guide 224 in position for the next sublayer, such as another zero degree sublayer; i. repeat the process a-h just described to add more sublayers as desired.

This altered process is different from the simple cell process for forming sublayers on the mandrel 220 where the guide has all the yarns necessary for a sublayer and the mandrel rotates in the same direction as it lays yarn back and forth between the pin rings. The altered process just described adds yarns to a sublayer by the continued rotation of the mandrel half the distance (or some other fraction) between the yarn guides 224, and then reversing the rotation of the mandrel to add yarns to that sublayer. If two more yarns were to be added between guided yarns instead of the one more yarn just described in the example above, the continued rotation would only be one third the distance between guides and this step would be repeated at the next pin ring. Similarly, if three more yarns were to be added, the continued mandrel rotation would only be one fourth of the distance between guides and this step would be repeated at the next two pin rings. When laying down yarns in this manner where the direction .i of rotation of the mandrel is reversed, it is important to minimise backlash in the apparatus and to minimise the unguided yarn length between the yarn guide and

S

the mandrel surface.

*050 There is a concern when laying down yarn on the mandrel of Figure 11 B that the path from the guide to the surface of the mandrel be as short as possible *000 S so the lay down position on the mandrel can be accurately predicted and 25 controlled. This is a concern in any of the yarn laydown devices. One way to accurately lay down the yarns with precision is to use the device in Figure 11 D which is shown in an end view of a mandrel 230' and circular guide support 222'. To illustrate a general case, the mandrel 230' is shown as an oval shape.

It will be appreciated that the mandrel shape may also vary along it axis.

Support 222' holds a plurality of guides, such as guide 224' that guides yarn 226. Each guide, referring to guide 224', includes a hollow shaft 280, a radiused guide tip 282, a spring 284, and a retainer 286. The shaft passes through a hole 288 in support 222'. Spring 284 is placed over shaft 280 between support 222' and tip 282 to thereby urge the tip toward the mandrel 280'. Yarn 226 passes through hollow shaft 280 and out through tip 282 and directly onto mandrel 230'. In this way, the yarn is laid directly onto the mandrel much as if it were "painted" on the mandrel surface. This insures accurate placement of the yarn on the mandrel. The shaft moves freely in hole 288 in support 222' to allow the guide tip to ride over any variations in the shape of the mandrel while the spring keeps tip 282, and the yarn 226 issuing therefrom, securely in contact with the mandrel surface. The tip 282 may advantageously be coated with a low friction coating for ease of sliding over the mandrel and the Syarns laying thereon.

Figure 20 shows another device for laying down yarn accurately on a compound curvature, such as a spherical surface, when using a robot or other :i mechanical actuator. There is a problem that the robot does not always follow complex curved paths in a continuous smooth motion and some irregular stepped motion is produced. It is useful to have some compliance in a yarn guide tip to keep it in contact with a curved mandrel surface during deviations in the path of the guide actuator or robot. Yarn guide 470 is attached to a slide 472 which is attached to a robot face plate 474. The slide is useful for fine positioning adjustments by way of screw 476 to set the initial deflection of the guide when programming the robot path. The guide 470 comprises a frame 478 that supports a hollow shaft 480 for rotation. A block 482 mounted on shaft 480 supports four thin flexible springs 484, 485, 486, and 487 (located behind 486).

Attached at the intersection of the springs is a hollow tip 488 with a hemispherical end 489. The springs permit motion of the tip in the axial direction 490 and in a conical direction defined by angle 492. Rotation of shaft 480 allows the tip to roll over any surface it contacts while it is also free to deflect axially and angularly. This allows the tip to accurately place a yarn 494 on the -21surface while the yarn is passing through the hole 496 in hollow shaft 480 and the hole 498 in hollow tip 488.

Figure 12 shows an apparatus that is used to make a simple three dimensional tubular batch fabric using a lathe-type device or a textile yarn winding device where the mandrel 290 rotates continuously by motor 291, but without translating, and the circular guide support 292 traverses along the mandrel axis back and forth driven by a cam or screw 294 rotated by a motor 293. Coordination of motors 291 and 293 provides control of the fabric structure. The pin rings of Figure 11 B may be eliminated by providing shoulders 295 and 296 to engage the yarn at the reversals and by keeping the bias angle low relative to the shoulder. This is a variation of the device shown in Figure 11 B which may allow fabrication of fabrics of the invention with slight o modification of existing mandrel systems.

:Figure 13 shows an apparatus that is used to make a continuous fabric where the two groups of yarn are oriented parallel and perpendicular to the direction of motion of the laydown belt. One group of yarns is supplied as a plurality of subgroups each comprising a plurality of yarns in a warp direction; and another group is supplied as a plurality of subgroups each comprising a plurality of yarns in a weft direction. A plurality of spaced ultrasonic bond paths connect the top and bottom subgroups together. The weft direction yarns are supplied by a process and apparatus similar to that disclosed in U.S. 4.030.168 to Cole hereby incorporated herein by reference.

In Figure 13 is an apparatus 500 for laying down subgroups of yarns 502, 504, 506, and 508 in the machine direction (MD) and combining them with subgroups of yarns 510, 512, 514, and 516 in the cross-machine direction (XD) on a conveyor surface 517 to continuously form a pre-bonded fabric structure 518. The subgroups of yarns 502, 504, 506 and 508 are guided onto the conveyor surface 517 by guides extending across the surface 517, such as guide bar 503 for subgroup 502. The guides, such as guide bar 503, may comprise rollers each having circumferential guide grooves (not shown) to act as 22individual yarn guides to guide each of a plurality of yarns spaced across the guide between the opposed edges of the conveyor surface for arranging the subgroup of yarns with respect to other MD yarns deposited on the conveyor surface. The guides, such as guide bar 503, may also comprise a group of spaced eyelets on a bar to guide each of a plurality of yarns in the subgroup of the group arranged in the machine direction. The subgroups of yarns 510, 512, 514 and 516 are guided onto the conveyor surface 517 by looped guides along the two opposed edges of belt 517, such as looped guides 505 on the near side and 507 on the far side for guiding subgroup 510. The looped guides have spaced yarn holders or clamps (not shown) for holding the spaced relationship S between the yarns in the subgroup of the group arranged in the XD direction.

The holders or clamps would release the yarn after it is deposited on the fabric support surface of the conveyor and on any MD yarns already placed there.

Preferably the XD yarns are not released by the clamps until they are engaged by the next MD yarns. In some cases, the MD yarns may be placed under tension and be able to provide enough support for the XD yarns so that a separate support surface is not required. An alternative to the endless loop conveyor surface illustrated may be a circular drum support surface, as long as the yarns S can be adequately held on the surface, such as with MD yarn tension or a vacuum, during rotation of the drum. The conveyor would be driven and have a vacuum applied similarly to the conveyor described in Figure 6. Fabric 518 is consolidated and connected by a plurality of spaced apart bonders located at position 520 to form a continuous fabric 522 of the invention. Contact roller 524 presses against conveyor roller 526 to positively drive the fabric without slippage on conveyor surface 517. The subgroup 502 comprises a sparsely spaced plurality of yarns that are spaced apart by a repeatable cell distance and are laid directly on a conveyor surface 517. The subgroup 504 comprises a sparsely spaced plurality of yarns that are also spaced apart by the same cell distance and are offset one yarn position (into the paper) from subgroup 502; subgroup 506 comprises a sparsely spaced plurality of yarns that are spaced 23 apart by the same cell distance and are offset from both 502 and 504; and subgroup 508 comprises a sparsely spaced plurality of yarns that are spaced apart by the same cell distance and are offset from all of subgroups 502, 504, and 506. The subgroup 510 comprises a sparsely spaced plurality of yarns with all the yarns, such as yarns 526 and 528, spaced apart a repeatable cell distance 530, which distance is the same for the spacing of all the yarns in the other subgroups 512, 514, and 516. This spacing determines the number of possible yarn positions for the yarns in the subgroups 510, 512, 514, and 516.

This controlled spacing and offset is best seen as the subgroups come together to form a fabric structure. The yarns in subgroup 510 are spaced apart at a cell distance at 532; the yarns in subgroup 512 are offset from subgroup 0°o' 510 by a repeatable offset 534 and are spaced apart by the cell distance at 536; the yarns in subgroup 514 are offset from subgroup 512 by a repeatable offset 538 and are spaced apart by the cell distance at 540; and the yarns of subgroup 516 are offset from subgroup 514 by a repeatable offset 542 and are spaced apart by the cell distance at 544. These yarns are shown in a position pattern of 0/4, 1/4, 2/4, and 3/4 going sequentially from subgroup 510 to subgroup 516.

This sequence could be different, such as 0/4, 3/4, 1/4, and 2/4, depending on 0 the pattern and structure desired. The same pattern sequence variations are also possible in subgroups 502, 504, 506, and 508 without regard to the patterns in subgroups 510-516. Films and other fiber materials may be inserted between subgroups of yarn as was suggested in Figure 6. In general terms, the process just described for forming an interlaced fabric structure comprises: providing an elongated fabric support surface having an elongated axis and opposed lateral edges, wherein a machine direction (MD) is defined in the direction of the elongated axis and a cross-machine direction (XD) is defined between opposed edges; laying down at the support surface a plurality of yarn subgroups having yarns oriented in the MD, each subgroup layed down at spaced locations -24along the elongated axis, the yarns in each one MD subgroup located at offset positions in the XD different from other MD subgroups; laying down at the support surface a plurality of yarn subgroups having yarns oriented in the XD, each subgroup layed down at spaced locations along the elongated axis, an XD subgroup spaced from a respective MD subgroup, the yarns in each one XD subgroup located at offset positions in the MD different from other XD subgroups; moving the support surface in a predetermined direction aligned with the elongated axis to bring together the yarns deposited from all MD and XD subgroups to form a stack; urging the subgroups together and connecting the top subgroup in the stack to the bottom subgroup in the stack to thereby form an interlaced Sfabric structure.

A variation of the process described in relation to Figure 13 is to preassemble the two orthogonal and adjacent subgroups, such as subgroups 502 and 510 to form a scrim. The four scrims 502/510, 504/512, 506/514, and 508/516 would be joined with the offsets between subgroups described above to make the same fabric structure. The preassembled subgroups could be temporarily assembled into the scrims with a size adhesive which is removed after final assembly and connecting of the upper and lower subgroups, or the connections between the preassembled subgroups could remain in the final fabric structure.

The flexible fabric of the instant invention can be made directly into a three dimensional shape referring to Figure 15 to Figure 18E. A flexible fabric can be made directly to shape by laying each subgroup directly onto a shaped surface.

Figure 15 shows an example of using a generalised dispensing system to create the fabric. A generalised actuator, in this case, a six degree of freedom robot 401, carries a single yarn dispenser 402, similar to that shown in Figure 20, to the desired positions and orientations to deposit a yarn 403 onto a shaped mandrel 404. The robot may also carry a plurality of yarn dispensers to deposit a plurality of spaced yarns simultaneously onto the shaped mandrel.

For a general shape, each group of yarns will include yarns that are cured in space. Preferably, neighbouring yarns in the group are generally parallel and the yarns of a group densely cover the region of the surface bounded by the outermost yarns of that group; a given group may not necessarily cover the entirety of the desired final shape. Figure 16A shows a plan view of the mandrel, Figure 16B and 16D show elevation views, and Figure 16C an isometric view. Referring to the figures, paths 410 are curved paths in space for one subgroup of one group of yarns on a spherical mandrel 411. This subgroup path S 410 consists of arcs 412, 413, 414, 415, 416, 417, 418, 419, 420, 421, 422, I 423, joined by connectors 424, 425, 426, 427, 428, 429, 430, 431, 432, 433, 434. Figure 16B clearly shows how the connectors join the arcs of subgroup path 410, such as connector 424 which joins arc 412 to arc 413.

The orientation of the subgroup paths 410 with respect to the mandrel 411 is given by two angles: a rotation about the z-axis 435 and an inclination about the x-y plane 436. To find the angle 435, start at the beginning of arc 412 at point 437 in the lower right of Figure 1 6D. Define a tangent vector 438 that travels along arc 412 leftwards in Figure 1 6D towards the first connector 424. The orientation of this tangent vector at Y 0 in Figure 16D is shown in the vector 439, seen also in Figure 16A. Angle 435 is defined as the angle from the positive x-axis 442 to vector 439, in the plan view 16A, which for the case shown is at -90 degrees. The subgroup paths 410 are inclined to the x-y plane 440 at an angle 436, which for the case shown is at +75 degrees. The angle 436 is inclined less than 90 degrees to insure that the yarns at the equator of this spherical mandrel cross in an intersecting relationship from subgroup to subgroup, rather than being nearly parallel if angle 436 were at 90 degrees.

Figures 17A-17D show two other subgroup paths 450 and 451 created by rotating the subgroup paths 410 about the z-axis. The plan view angle, equivalent to angle 435, for path 450 is 300 and for path 451 is 1500. In -26this example, the three groups of subgroups are evenly spaced, with the plan view angle 435 of path 450 being 1200 from path 410 and the plan view angle 435 of path 451 being -120 from path 410. The number of groups and the necessary angles 435 and 436 for each group may be varied to provide the required structural properties of the shaped fabric.

The subgroup path 410 defines the skeleton of paths for the entire group of yarns in this general direction. Other subgroups in this group are found by placing yarns in offset positions along the surface, generally parallel to the sparse yarns of the skeleton 410. In general, the subgroups of a directional group are not simply shifted versions of each other, as in the flat case; they have slightly different shapes. Other subgroups for the yarns in the other group directions 450 and 451 are found by offsetting the subgroup paths 450 and 451 similarly Salong the surface of the mandrel for those general directions.

Figures 18A-18E illustrate a summation and completion of what was discussed referring to the yarn paths of Figures 16A-D and 17A-D. Figures 18A- E show the progression of yarn from a single subgroup in Figure 18A; to the first subgroups of three groups in Figure 18B; to the first two subgroups of three groups in Figure 18C; to the first three subgroups of three groups in Figure 18D; to four subgroups of three groups in Figure 18E, in this case, densely covering the desired surface region to form shaped fabric structure 452. In this example, the yarns in each subgroup are spaced 4 yarns apart, and each subgroup is offset from the previous group by a single position. A similar procedure can be used for groups with different number of yarns (say 3 to 8 yarns) separating the yarns in each subgroup, or a different offset sequence for successive subgroups (say 0/4, 2/4, 1/4, 3/4 instead of the 0/4, 1/4, 2/4, 3/4 sequence shown).

Each family of subgroup paths 410, 450, or 451, making up each of the three groups of yarn paths need not cover the entire final surface region desired, and need not be similar to each other, as in this example. For a general shape with less symmetry, the different groups will not be similar. One may choose as many groups in as many general directions as necessary to cover the desired -27surface region such that at every point, there are at least two groups of crossing yarns, and the crossing angle is sufficient to meet the mechanical property requirements of the fabric. Figure 18E shows that the flexible fabric structure 452 may combine triaxial regions 460, having three yarn directions, with biaxial regions 461, having two yarn directions.

To fabricate the fabric, (referring to Figures 15, 1 6A-D, and 17 A-D) the generalised actuator may be taught or programmed to dispense yarn along the subgroup paths defined for each group. The dispenser may dispense a single yarn by traversing sequentially the arc 412, then the connector 424, then the arc 413, then the connector 425, etc., then the arc 422, then the connector 434, K then the arc 423. Alternately, a dispenser can dispense all the arcs 412, 413, 414, 415, 416, 417, 418, 419, 420, 421,422, 423 simultaneously in one pass.

Alternately, a dispenser can dispense selected numbers of the arcs such as the arcs 412, 413, 414 in one pass; and complete remaining arcs in succeeding passes of arcs 415, 416, 417, then 418, 419, 420, and then 421, 422, 423; using some or all of the connectors 424, 425, 426, 427, 428, 429, 430, 431, 432, 433, 434. Alternatively to laying yarn down in the connectors paths, the yarns may be cut at the end of an arc and reattached to the mandrel at the beginning of the next arc. In this way yarn from succeeding subgroups would not accumulate at the connector paths.

Subgroups in the other directions may be laid down by teaching or programming the robot along those paths, or in certain symmetric cases such as this one, by rotating the mandrel about the z-axis 441 by the desired angle 435 and repeating the program for path 410. Generally for non-symmetrical shapes, however, subsequent subgroups would be taught or programmed independently since they are not simple translation offsets of the path 410 for the first laid subgroup of the first group.

Yarn tension control is important during the dispensing along these paths to maintain the yarn onto the generally curved path. Excessive tension will cause the yarn to deviate significantly from the desired path. Preferably, a temporary 28 aid, either mechanical or adhesive, is used on the mandrel surface and on yarns in preceding subgroups to maintain the yarn on the desired path. For instance, a pressure-sensitive adhesive may be sprayed on the mandrel at the start and on each succeeding subgroup of yarn to aid in holding the applied yarns in place. To further assist, a roller may be used on each subgroup to press the adhesive covered yarns onto the mandrel and each other. These aids may remain in the final fabric, or be removed after the final connecting step.

The final step is to connect the final subgroup to be laid down in each region, the top subgroup, with the first subgroup to be laid down in that region, the bottom subgroup, at the crossing points between the two subgroups. In S.o general, the top and bottom subgroups are arranged to be crossing one another.

Since each group does not necessarily cover the entire surface (but covers a substantial portion greater than 1/3 and preferably greater than 1/2 of the fabric 6*.

area), the top and bottom subgroups may be different subgroups from different groups in the triaxial and biaxial regions. It is also possible to connect the top and bottom yarns to yarns in intermediate subgroups at a plurality of spaced locations, rather than making precise direct connections between the top and bottom subgroup yarns. Such a process was discussed when describing the flat fabric structures.

In general terms, the above process makes a three dimensional, shaped, interlaced, fabric structure, comprising: a stack of a first plurality of subgroups, a second plurality of subgroups, and a third plurality of subgroups, each subgroup having yarns spaced apart to define a sparse covering of a fabric area, the yarns generally parallel, and the yarns following a curved path in space; the stacked subgroups arranged in a predetermined array with reference to a common axis and a common reference plane perpendicular to said axis; the first subgroups arranged at a first angle with respect to said reference plane and positioned at a first rotational angle about said axis, the 29 second subgroups arranged at a second angle with respect to said reference plane and positioned at a second rotational angle about said axis, the third subgroups arranged at a first angle with respect to said reference plane and positioned at a third rotational angle about said axis, wherein the yarns in any one of the first, second and third subgroups cross the yarns in another of the first, second and third subgroups; within each first, second and third plurality of subgroups, the yarns of one subgroup are offset from the yarns of the other subgroups to thereby form a group of yarns for each of the respective subgroups, the group for any respective subgroups densely covering a fabric area; the top subgroup in the stack is connected to the bottom subgroup in the stack to thereby form a three-dimensional, shaped interlaced, fabric structure.

The fabric of the invention can also be wound on a composite rectangular parallelepiped form to make biaxial three dimensional fabric structures referring to Figures 19A-D. Figure 19A shows a composite rectangular mandrel 300 that is the general configuration of the desired shape, which in this case would be a short sleeve shirt. The mandrel may be a solid form made of connected Srectangular parallelepiped pieces, such as torso piece 310, and a shoulder piece 312 detachably connected with rods or screws or clamps (not shown). The mandrel may also be a frame structure outlining the shape, or an expandable/collapsible structure to assist in removal of the finished fabric.

To handle the form, and rotate it around three axes for ease of fabric forming, there are two pairs of gripper devices arranged in a framework (not shown) surrounding the mandrel. A suitable framework for supporting the grippers for rotation and translation and a variable speed motor for driving them can be provided by one skilled in machinery art and will not be discussed further here. Referring to Figure 19A, a first pair of opposed grippers 302 and 303 are arranged to support the mandrel 300 for rotation about first mandrel axis 314. A second pair of opposed grippers 304 and 305 are arranged for supporting the mandrel 300 for rotation about second mandrel axis 316. Referring to Figure 19B, the mandrel can be reoriented 90 degrees from the position in Figure 19A and the second pair of opposed grippers 304 and 305 are arranged for supporting the mandrel 300 for rotation about third mandrel axis 318. Each pair of grippers are moveable rotationally and axially toward and away from one another; that is, gripper 302 can rotate and move axially toward and away from gripper 303, and gripper 303 can also rotate and move axially toward and away from gripper 302.

In Figure 19A, grippers 304 and 305 have both moved axially to engage the ends of mandrel piece 312 to rotate mandrel 300 about axis 316. The face of each gripper of the pair engaging the ends of the mandrel may be covered with a resilient high friction surface to securely grip the mandrel and any fabric laid there, or they may be covered with pins or needles to engage the ends of the mandrel and fabric. There is a first yarn guide 306 for winding a first yarn 307 onto mandrel 300 about axis 316. The guide 306 is supported and propelled by 1 5 a rotating threaded rod 320 for transverse motion parallel to axis 316. The rod is supported by simple supports and driven by a variable speed motor not shown.

The rotation of the mandrel grippers 304/305 and rod 320 are coordinated by a controller 321 so in one revolution of grippers 304/305 the yarn 307 moves one cell distance 322 along the mandrel 300 to lay down a first subgroup of yarn in the direction 324 on the mandrel. After covering the mandrel with one subgroup of yarn, the winding stops and grippers 302 and 303 engage the mandrel and grippers 304 and 305 retract. Grippers 302/303 rotate the mandrel 90 degrees and stop, grippers 304 and 305 re-engage the mandrel, and grippers 302 and 303 retract. This places the mandrel in the position shown in Figure 19B.

Referring to Figure 19B, grippers 304 and 305 have both moved axially to engage the sides of mandrel piece 312 to rotate mandrel 300 about axis 318.

The first yarn guide 306 is now arranged for winding yarn 307 onto mandrel 300 about axis 318. The guide 306 will now be supported and propelled by the rotating threaded rod 320 for transverse motion parallel to axis 318. The rotation of the mandrel grippers 304/305 and rod 320 are coordinated so in one -31 revolution of grippers 304/305 the yarn 307 moves one cell distance 332 along the mandrel 300 to lay down a first subgroup of yarn in the direction 334 on the mandrel.

When winding yarn about axis 318 of mandrel 300, in order to lay down the yarn on the mandrel in the underarm of the shirt form, a special yarn deflector is used that is best seen in Figure 19D, which is a side view of the mandrel and grippers shown in Figure 19B. As the mandrel 300 is rotated, at one point the yarn 307 lies along dashed path 336 and across underarm 338 of the mandrel. At this point, a yarn deflector 340 moves from a retracted position 342 to an extended position 344 and tucks the yarn into the underarm where an insert 346 having temporary fasteners, such as hooks or adhesive, engages the yarn and holds it in position in the underarm. The deflector 340 then quickly returns to the retracted position 342 and the mandrel continues rotating and yarn continues being laid down. As the mandrel continues rotating and the other underarm 348 comes into the vicinity of the deflector 340, this cycle is repeated and the deflector tucks the yarn into underarm 348 where it is engaged by temporary fastener insert 350.

Referring to Figure 19C, grippers 302 and 303 have both moved axially to engage the ends of mandrel 300 to rotate it about axis 314, and grippers 304 and 305 have retracted. The face of each gripper of the pair 302/303 engaging the ends of the mandrel may be covered with a resilient high friction surface to securely grip the mandrel and any fabric laid there, or they may be covered with pins or needles to engage the ends of the mandrel and fabric. There is a second yarn guide 326 for winding a second yarn 328 onto mandrel 300 about axis 314.

The guide 326 is supported and propelled by a rotating threaded rod 330 for transverse motion parallel to axis 314. The rotation of the mandrel grippers 302/302 and rod 330 are coordinated so in one revolution of grippers 302/303 the yarn 328 moves one cell distance 333 along the mandrel 300 to lay down a first subgroup of yarn in the direction 335 on the mandrel.

-32- To make a densely covered mandrel using four subgroups of yarn in each of the three directions, the following sequence of operations is preferred, although other sequences are possible: the mandrel is gripped by grippers 304/305 as in Figure 19B and the yarn 307 is attached to a corner 352 of the mandrel; grippers 304/305 rotate mandrel 300 about mandrel axis 318 and yarn 307 is traversed by moving guide 306 to achieve a cell distance of 332; the yarn is stopped at about position 354 and is cut and attached to the mandrel; grippers 302/303 engage the mandrel 300 and grippers 304/305 retract as in Figure 1 9C and the yarn 328 is attached to a corner 356 of the mandrel; 15 grippers 302/303 rotate mandrel 300 about mandrel axis 314 and yarn 328 is traversed by moving guide 326 to achieve a cell distance of 333; the yarn 328 is stopped at about position 358 and is cut and attached to the mandrel; "grippers 304/305 engage the mandrel 300 and grippers 9099 302/303 retract as in Figure 1 9A and the yarn 307 is attached to a corner 360 of the mandrel; grippers 304/305 rotate mandrel 300 about mandrel axis 316 and yarn 307 is traversed by moving guide 307 to achieve a cell distance of 322; the yarn 307 is stopped at about position 362 and is cut and attached to the mandrel; grippers 302/303 engage the mandrel and grippers 304/305 retract and grippers 302/303 rotate mandrel 300 to the position in Figure 19B; -33grippers 304/305 engage the mandrel and grippers 302/303 retract as Figure 19B and the yarn 307 is attached near corner 352 except at an offset position of one, two, or three yarn diameters from position 352; yarn is wound once more about mandrel axis 318 at the offset position and is cut and attached near position 354; grippers 302/303 engage the mandrel 300 and grippers 304/35 retract as in Figure 1 9C and the yarn 328 is attached near corner 356 of the mandrel except at an offset position of one, two, or three yarn diameters from position 356; .yarn is wound once more about mandrel axis 314 at the offset position and is cut and attached near position 358; grippers 304/305 engage the mandrel 300 and the grippers 302/303 retract as in Figure 19A and the yarn 307 is attached to a near corner 360 of the mandrel except at an offset position of one, two, or three yarn diameters from position 360; yarn is wound once more about mandrel axis 316 at the offset position and is cut and attached near position 362; the above process continues with succeeding yarns wound about a given mandrel axis being offset from preceding yarns until the mandrel is densely covered with the four subgroups of yarns in the three directions. On any given face of the mandrel, there will be yarns in only two directions, thereby forming a biaxial fabric structure on each face; on each face of the mandrel, the outermost subgroup of yarns are connected to the innermost subgroup of yarns where the outermost yarns cross the innermost yarns, by application of an ultrasonic horn only at the crossovers, with the mandrel acting as an ultrasonic anvil. Alternatively, a plurality of -34spaced ultrasonic horns could be traversed over each face of the mandrel in a diagonal path relative to the directions of the yarns on that face, similar to what was taught with the flat fabric structures; after connecting is complete, the mandrel can be removed from the grippers and the sleeve ends of the fabric shirt can be cut open and mandrel piece 312 disengaged from piece 310 and piece 312 slid out of the cut sleeve opening; the waist end of the fabric shirt can be cut open and mandrel piece 310 slid out of the cut waist opening; the cut ends of fabric may be removed or may be used to ~form cuffs on the sleeves and waist of the shirt.

0 :Using the above technique, three dimensional fabric articles of clothing can be made easily using relatively simple mandrels. By winding in a simple manner about three axes of the mandrel, a bidirectional yarn, three dimensional fabric can be made without cutting and seaming separate fabric pieces as in the prior art. This produces unique articles of fabric clothing without seams.

Figure 19E illustrates the yarn pattern as seen on a corner of the mandrel at the end of a sleeve at corner 364 as also seen in Figure 19A.

The mandrel axes are labelled at 366. Several of the first subgroup of yarns laid down about the mandrel axis 318 are labelled 1; several of the second subgroup of yarns laid down about the mandrel axis 314 are labelled 2. Several of the third subgroup of yarns laid down about mandrel axis 316 are labelled 3. The subgroups are labelled in the order in which they are laid on the mandrel. For subgroups above three, only one yarn in the subgroup is labelled to illustrate the pattern that develops on the mandrel. The group of yarns laid down about mandrel axis 318 are labelled with the number 1 for the first subgroup, the number 4 for the fourth subgroup, the number 7 for the seventh subgroup, and the number for the tenth subgroup. The group of yarns laid down about mandrel axis 314 are labelled with the number 2 for the second subgroup, the number 5 for the fifth subgroup, the number 8 for the eighth subgroup, and the number 11 for the eleventh subgroup. The group of yarns laid down about mandrel axis 316 are labelled with the number 3 for the third subgroup, the number 6 for the sixth subgroup, the number 9 for the ninth subgroup, and the number 12 for the twelfth subgroup. Although yarns are wound about three axes of the mandrel, on mandrel face 368, the yarns form a biaxial structure; on mandrel face 370, the yarns form a biaxial structure; and on mandrel face 372, the yarns form a biaxial structure.

Points 374 and 376 on face 368 show some typical bond points between the outmost subgroup 11 and the innermost subgroup 1. Points 378 and 380 on mandrel face 370 show some typical bond points between the outermost subgroup 12 and the innermost subgroup 2.

Points 382 and 384 on mandrel face 372 show some typical bond points between the outermost subgroup 12 and the innermost subgroup 1. In general terms, the process just described for forming an interlaced shaped ~fabric structure comprises: providing a rectangular parallelepiped fabric support surface rotatable in three orthogonal axes thereby defining three orthogonal yarn laydown directions X, Y, and Z; laying down a first subgroup of yarns to sparsely cover the support surface in said X direction; laying down a second subgroup of yarns to sparsely cover the support surface in said Y direction and form a stack with the yarns in the X direction and the Y direction; laying down a third subgroup of yarns to sparsely cover the support surface in said Z direction and form a stack with the yarns in the X direction and the Y direction; -36repeating the laying down and stacking for each of the first, second and third subgroups and offsetting the yarns in subsequent subgroups from all yarns in previous subgroups until each of the plurality of subgroups forms a group of yarns in the respective direction for that subgroup that densely covers the mandrel surface; connecting the top subgroup in the stack to the bottom subgroup in the stack thereby forming a shaped interlaced fabric structure.

EXAMPLES

EXAMPLE 1 A fabric structure was made from a sheath/core yarn of 710 total e denier which included a 400 denier core of continuous multifilaments of nylon 6,6 flat yarn having 6 denier per filament. The core was wrapped with a sheath of staple fibers comprised of a nylon 6,6 copolymer S 15 containing 30% by weight of units derived from MPMD (2-methyl pentamethylenediamine) which had a melt point lower than the core polymer. The staple fibers being wrapped on the core were a sliver of inch staple length and 1.8 dpf. This yarn was made on a "DREF 3 Friction SSpinning Machine" manufactured by Textilemachinenfabrik Dr. Ernst Fehrer AG of Linz, Austria. The fabric structure had 16 subgroups arranged as in Figure 2A and was wound on a device as in Figure 11 B. The fabric cell distance contained 8 yarns. The bonds were made circumferentially using an ultrasonic generator made by the Dukane Co., model #351 Autotrak, which was operated at 40kHz with a force against the mandrel of about 4- 5 Ibs. The horn speed along the mandrel was such that about 0.2 joules per bond of ultrasonic energy was applied to the fabric. The bond paths were spaced about 0.2 inches apart and the horn tip was about 0.1 inch wide and 0.75 inches long with a slightly concave surface across the 0.1 dimension for about 0.5 inches of the length. At the concave end of the bonding surface, there was a radius to eliminate the leading corner and the -37concavity followed the radius. The horn did not make full contact along the 0.75 inch dimension due to the radius of the mandrel. The horn made highly bonded regions at the edges of the concave surface. It is believed that an improvement in bonding would be realised with a narrower horn of about 0.04 inches width with a flat bonding surface instead of a concave one.

After bonding, the fabric was removed from the mandrel and was given a tensile test in a direction parallel to one group of the yarns. The maximum theoretical tensile strength of this fabric without any bonds was computed to be 148 Ibs/inch by multiplying the yarn strength of 4.6 Ibs by 32 yarns per inch. The bonded fabric of the invention had an actual grab strength of about 120 Ibs/inch. It is believed that the sheath/core yarn bonded by primarily melting the lower melting sheath, while the core filaments remained essentially undisturbed, so the strength of the fabric was not significantly diminished due to bonding. In another test of a fabric made with 630 denier nylon 6,6 multifilament yarn without the low melting sheath structure, the theoretical unbonded fabric tensile strength was 370 Ibs/inch, and the actual bonded grab strength was 120 Ibs/inch.

obe* This indicated a significant reduction in strength for the bonded multifilament yarn compared to the strength reduction with the bonded low melting sheath. The low melting sheath offers a significant strength

S

improvement when ultrasonic bonding is used for connecting the yarns.

EXAMPLE 2 A fabric structure was made with limited permeability by inserting film sheets in the fabric structure during fabrication. A sample was made using 630 denier continuous multifilament yarn wound on the device of Figure 11 B and bonded with the ultrasonic system described in Example 1.

The fabric cell distance contained 8 yarns. The film sheet was about a mil thick Bynel polypropylene film. -The fabric was made by first laying two subgroups on the mandrel followed by a sheet of film, followed by 12 -38subgroups of yarn, followed by another sheet of film, followed by 2 subgroups of yarn. The fabric was then bonded in the manner of Example 1. The fabric was removed from the mandrel and when examined by blowing air at the fabric, it was found that very little air passed through the fabric and this occurred only at the bonded region.

EXAMPLE 3 A reinforced fabric structure was made by adding a sheet of spunbonded nonwoven fabric in the structure during fabrication. The yarn was the same yarn as in Example 2. The nonwoven was a low melt copolymer polyamide weighing about 1 ozlsq yd. The fabric was made in the manner of Example 2. Fourteen subgroups of yarn were wound on the 0O9* mandrel, the nonwoven sheet was laid on the mandrel and two subgroups of yarn were wound over the nonwoven. The fabric was bonded in the 1 manner of Example 1. The fabric was removed from the mandrel and was found to have improved strength and reduced deflection in the bias direction.

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EXAMPLE 4 A preform for a composite panel was made using a non- 9* thermoplastic yarn and sheets of thermoplastic film. The yarn was 840 denier continuous multifilament aramid (Kevlar T M flat yarn. The film sheet was a 2-3 mil thick polyester film. The fabric was made in the manner of Example 2. Two subgroups of yarn were wound on the mandrel, followed by a film sheet, followed by four subgroups of yarn, followed by a film sheet, followed by four subgroups of yarn, followed by a film sheet, followed by four subgroups of yarn, followed by a film sheet, followed by two subgroups of yarn, for a total of 1 6 subgroups of yarn and four film sheet. The film made up about 15% by weight of the fabric. The fabric was bonded in the manner of Example 1. The fabric was removed from the mandrel and was found to have adequate integrity for handling as a composite preform.

-39- EXAMPLE A fabric was made with a cotton sliver web inserted during fabrication to make a fabric that was soft to the touch. The yarn was the same as used in Example 2. The cotton was a sliver formed into a web of about 8 x 11 inches and about 0.5 oz/sq yd weight. The fabric was made in the manner of Example 2. Eight subgroups of yarn were wound on the mandrel, followed by the cotton web, followed by eight subgroups of yarn.

The fabric was bonded in the manner of Example 1. The fabric was removed from the mandrel and was found to be a soft coherent structure, but it could be separated along the cotton web. It is believed that the integrity of the structure could be improved by adding some nylon 6,6 0O*O staple, or a low melting copolymer nylon 6,6 staple, to the cotton sliver by blending before making the cotton web. It is believed this would improve the bonding of the nylon yarns together through the cotton web.

15 EXAMPLE 6 A fabric structure was made with natural fibers as the inner 0 e g. subgroups and thermoplastic fibers as the first and last subgroups. The structure used 8 feed yarns with 28 subgroups. The natural cotton yarns had a denier of 1600, while the thermoplastic yarns were nylon 6,6 of 630 000S total denier. The laydown sequence was as follows: first subgroup was oO•nylon 6,6; next 26 subgroups were cotton; and the last subgroup was o nylon 6,6. The structure was then bonded by tracing the path of each yarn in the last subgroup with the ultrasonic horn, bonding along the length to bond each intersection of the first and last subgroup.

EXAMPLE 7 A fabric structure was made of Dacron T M yarns (1.3 dpf, 255 total denier) consisting of repeating groups of subgroups. The fabric consisted of a two-layered fabric structure where one layer is a stack of two groups of subgroups that form a densely covered area, and the other layer is an identical group of subgroups that form a second densely covered area.

The resulting fabric had a basis weight equivalent to a fabric consisting of the same number of total subgroups that were parallel but offset with no subgroups on top of one another, but gave a bulkier feel and appearance.

For comparison, three separate fabrics were made to explore the effect of different fabrication techniques on the bulk of the finished fabric.

All fabrics were made using the above yarn placed in 16 guides in the ring of the device of Figure 11 B. All fabrics were bonded the same using the circumferential bonding process of Example 1. Fabric A was comprised of two groups of yarns having a combined total of 18 subgroups, and with 9 yarns per cell space to make a 1 oz/yd 2 fabric. Fabric B was comprised of two group of yarns having a combined total of 36 subgroups, and with 18 yarns per cell space to make a 2 oz/yd 2 fabric. The yarns in Fabric B were more closely packed in the same cell space as were the yarns of Fabric A.

Fabric C was comprised of a two-layered fabric structure where a first

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15 layer like Fabric A was formed, and then a second layer like Fabric A was formed on top of the first layer to make a fabric with a combined total of 36 subgroups of yarn to make a 2 oz/yd 2 fabric. The two layers were bonded only after both layers were wound onto the mandrel. The 3 fabrics were removed from the mandrel and were examined visually and by S 20 hand for bulk. Fabric A seemed to have the last bulk; Fabric C hand the most bulk; Fabric B had a bulk level between that of Fabric A and Fabric C.

It was surprising that packing more yarn into a cell space produced more oooo° bulk (comparison of Fabric A and Fabric B) and that a two-layered structure with the same quantity of yarn produced more bulk (comparison of Fabric B and Fabric Since all fabrics were bonded the same, this indicated that yarn packing and layering can also be used to control bulk.

EXAMPLE 8 Miscellaneous samples were made using two ply, bulked, continuous filament (BCF) nylon 6,6 carpet yarn of 2500 denier and 19 denier per filament; and using staple nylon 6,6 carpet yarn. The bonding -41energy for this large denier yarn may be as much as 1-2 joules of ultrasonic energy per yarn crossing. Miscellaneous samples were also made using 150 denier, 0.75 denier per filament textured polyester yarn.

Flat and three dimensional samples were also made manually using 1/8-1/4 inch diameter rope or cord and plastic ties for connecting the yarns where the outermost subgroups cross.

The fabric structure of the invention can be made by a variety of ways, including by manual and automated means, either in a batch or continuous manner, and using a wide variety of yarns and connecting means.

Where the terms "comprise", "comprises", "comprised" or "comprising" are used in this specification, they are to be interpreted as specifying the presence of the stated features, integers, steps or 15 components referred to, but not to preclude the presence or addition of one or more other feature, integer, step, component or group thereof.

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Claims (12)

1. A yarn dispensing device for laying down yarn accurately on a compound curvature, when using a mechanical actuator, comprising the following elements: a mechanical guide actuating means; a yarn guide comprising a frame that supports a hollow shaft through which yarn can pass; a block mounted on said hollow shaft which supports a plurality of flexible springs that intersect at a common point; at the point of intersection of the springs is a hollow tip with a hemispherical end through which the yarn can pass, said springs permitting motion of the tip in an axial or angular direction, the rotation of said shaft allowing the tip to roll over any surface it contacts while it is also free to deflect axially and angularly, so as to accurately place a yarn on the surface while the yarn passes through a hole in the hollow shaft and a hole in the hollow tip.

2. A method of forming a fabric of interlaced yarn, comprising: providing an elongated fabric support surface having an ~elongated axis and opposed lateral edges parallel to the axis, and arranging the surface adjacent a plurality of yarn guide blocks arranged along opposed lateral edges of the elongated surface; providing a plurality of guides on said guide block, each guide adapted to guide a yarn from a yarn source to the support surface; engaging the yarns at one edge of said support surface; providing relative motion between the support surface and each of the plurality of guide blocks so that the guide 0 43 blocks deposit yarn from the guides onto the surface in a first diagonal direction relative to the edge of the surface and in a predetermined direction along the support surface; engaging the yarns at an opposed edge of said support surface; reversing the relative motion of the guide blocks and support surface so that the guide blocks deposit yarn from the guides onto the surface in a second diagonal direction relative to the edge of the surface and in said predetermined direction; arranging said guide blocks and guides and arranging said relative motion so that when said yarns from said blocks S' are deposited on said surface, the diagonal positions of each said yarn are offset from the other yarns to thereby densely cover the support surface with said yarns in one cycle of relative motion from one edge to the opposite edge and back to the one edge.

3. The method of Claim 2 wherein providing relative motion comprises moving said support surface in a predetermined direction along said axis of said surface and moving said guide blocks in a direction along a path from said one edge to said opposed edge, said path substantially perpendicular to said axis.

4. The method of Claim 3, in which at least one said block is arranged along one edge and at least another said block is arranged along said same edge and said one and another of said blocks move from one edge to said opposed edge in unison during said providing of relative motion.

The yarn product made by the process of Claim 4.

6. The method of Claim 2, in which at least one said block is arranged along one edge and at least another said block is arranged along said opposed edge and said one and another of said blocks move toward and I, U. 1, -44- away from each other as they move from one edge to an opposed edge during said providing of relative motion.

7. The yarn product made by the process of Claim 6.

8. A process of forming a fabric of interlaced yarn, comprising: providing an elongated fabric support surface on a rotatable mandrel having a rotational axis and opposed lateral ends substantially perpendicular to said axis, and orienting the surface adjacent a circumferential yarn guide ring substantially perpendicular to said axis, the ring arranged adjacent a lateral end of the fabric support surface; providing a plurality of guides on said guide ring, each guide adapted to guide a yarn from a yarn source to the support surface, the guides equally spaced to deposit yarn at equal intervals around the mandrel circumference; S 15 engaging the yarns at one end of said support surface; providing relative motion between the support surface and the guide ring so that the ring deposits yarn from the guides onto the surface in a first diagonal direction relative to the ends of S• the surface from one end to the opposed end and in a predetermined rotational direction along the support surface thereby sparsely covering the fabric area on the mandrel surface with yarns in said first direction; engaging the yarns at an opposed end of said support surface; reversing the relative motion of the guide ring and support surface so that the guide ring deposits yarn from the guides onto the surface in a second diagonal direction relative to the ends of the surface from said opposed end to said one end and in said predetermined rotational direction along the support surface thereby sparsely covering the fabric area on the mandrel surface with yarns in said second direction; A I 6 arranging said guide ring and guides and arranging said relative motion so that when the yarns from said guides on the guide ring are subsequently deposited on said surface, the diagonal positions of subsequently deposited yarns are offset from previously deposited yarns in each first and second diagonal direction to thereby densely cover the support surface with said yarns after repeated cycles of relative motion from said one end to the opposed end and back to said one end.

9. The method of Claim 8, wherein arranging said relative motion comprises stopping said relative motion between said guide ring and said mandrel support surface when said guide ring first returns to said one end and continuing said predetermined rotation of said mandrel surface for a predetermined distance to place a subsequently deposited yarn in a i °'"predetermined offset position relative to a previously deposited yarn in said 1 first direction and before the reversing of said relative motion; and repeating said stopping, said continuing, and said reversing at said 9 opposed end to place a subsequently deposited yarn in a predetermined offset position relative to a previously deposited yarn in said second direction and before the reversing of said relative motion; and stopping 0020 said relative motion between said guide ring and said mandrel support surface when said guide ring has placed a yarn in all offset positions for each first and second directions to thereby densely cover a fabric area on the mandrel support surface.

An interlaced fabric structure made by the process of Claim 8.

1 1. The method of Claim 9 wherein continuing said predetermined rotation of said mandrel surface for a predetermined distance comprises: defining equal subintervals of offset positions between the first deposited yarns in the first and second directions; 4 .p (.I -46- sequentially continuing said predetermined rotation at said one end and opposed end to place subsequently deposited yarns in each direction at these subintervals; further sequentially continuing said predetermined rotation at said one end and opposed end to progressively place yarns in each subinterval at a distance from previous yarns of one yarn offset to thereby complete the placing of yarns in all offset positions in all the subintervals together.

12. A yarn dispensing device as claimed in Claim 1 or a method or process of forming a fabric as claimed in any one of claims 2-4, 6, 8, 9 or 11, substantially as hereinafter described with reference to the drawings and/or Examples. C DATED this day of 2001 E. I. DU PONT DE NEMOURS AND COMPANY C By their Patent Attorneys: CALLINAN LAWRIE