Break-out apparatus for fault prevention in the production of multi-strand yarns

Abstract

Apparatus and processes for breaking out a residual strand where one strand breaks in a strand combining operation. The invention makes use of the change in the line of travel of the residual strand to effect break out in the new line of travel.

We claim:  .[.1. Apparatus for breaking out yarns having fewer strands than desired where two or more strands are combined into a yarn, said apparatus comprising a guide for constraining the combined strands laterally of their general direction of travel, the guide being mounted for lateral movement under pressure from a residual strand in the absence of the other to allow the residual strand to adopt a respective modified line of travel, and strand breaker means arranged to act on a strand adopting a said modified line of travel to effect breakout of that strand..]. .[.2. Apparatus for breaking out yarns having fewer strands than desired where two or more strands are combined into a yarn, said apparatus comprising a guide for constraining the combined strands laterally of their general direction of travel, the guide being mounted for lateral movement under pressure from a residual strand in the absence of the other to allow the residual strand to adopt a respective modified line of travel, and strand breaker means arranged to act on a strand adopting a said modified line of travel to effect breakout of that strand; said strand breaker means includes a pair of co-operating members disposed to allow free or intermittently free passage of the travelling strands within a predetermined spacing laterally of their general direction of travel, but to nip strands located at either side of this spacing..]. .[.3. Apparatus according to claim 2 wherein the cooperating members comprise a pair of rotatable rollers one of which has a relieved portion in its curved surface determining said spacing..]. .[.4. Apparatus according to claim 3 including damping means disposed to act on said guide to reduce its lateral movement with the combined strands due to random jitter or the like..]. .[.5. Apparatus according to claim 3 wherein the guide is mounted for said lateral movement being supported for pivotal movement in a plane transverse to the general direction of travel of the converged strands..]. .[.6. Apparatus according to claim 3 wherein one of said rollers is detachably supported in a cradle carried on the other roller such that the other roller acts as a bearing about which the cradle is rotatable between respective operational and withdrawn conditions..]. .[.7. Apparatus according to claim 1 wherein the strand breaker means comprises a pair of opposed abrasive surfaces..]. .[.8. Apparatus according to claim 1 including damping means disposed to act on said guide to reduce its lateral movement with the combined strands due to random jitter or the like..]. .[.9. Apparatus according to claim 1 wherein the guide is mounted for said lateral movement being supported for pivotal movement in a plane transverse to the general direction of travel of the converged strands..]. .[.10. Apparatus according to claim 1 including detector means mounted to detect lateral movement of a strand to a respective said modified line of travel, wherein said strand breaker means is connected to said detector means for energization by the detector means to effect the breakage of the residual strand upon the absence or breakage of the other..]. .[.11. The apparatus for forming yarns having at least two strands combined together, which apparatus includes means to feed two strands at equal rates from spaced feeding points, means to twist the travelling strands together into a single yarn, structure to break out yarns having fewer strands than desired comprising a convergence guide defining a convergence point for the strands, the guide being mounted for lateral movement under pressure from a residual strand in the absence of the other to allow the residual strand to adopt a respective modified line of travel, and strand breaker means arranged to act on a strand adopting a said modified line of travel to effect breakout of that strand..]. .[.12. Apparatus for forming yarns having at least two strands combined together, which apparatus includes means to feed two strands at equal rates from spaced feeding points, means to twist the travelling strands together into a single yarn, structure to break out yarns having fewer strands than desired comprising a convergence guide defining a convergence point for the strands, the guide being mounted for lateral movement under pressure from a residual strand in the absence of the other to allow the residual strand to adopt a respective modified line of travel, and strand breaker means arranged to act on a strand adopting a said modified line of travel to effect breakout of that strand; said strand breaker means includes a pair of co-operating rollers disposed to allow free or intermittently free passage of the travelling strands within a predetermined spacing laterally of their general direction of travel but to nip strands located to either siade of this sapcing, the spacing being determined by a relieved portion in the curved surface of one of the rollers..]. .[.13. Apparatus according to claim 12 wherein one of said rollers is detachably supported in a cradle carried on the other roller such that the other roller acts as a bearing about which the cradle is rotatable between respective operational and withdrawn conditions..]. .[.14. Apparatus according to claim 13 including damping means disposed to act on said guide to reduce its lateral movement with the combined strands due to random jitter or the like..]. .[.15. A method of breaking out yarns having fewer strands than desired where two travelling strands are fed from spaced feeding point and combined into a single yarn, comprising providing at least one strand breaker means at a fixed location spaced from the travelling strands and allowing the residual strand to adopt a respective modified line of travel when one of the strands break out, in which line of travel of residual strand operatively contacts said strand breaker means at said fixed location which then acts on the residual strand to also effect break out of that strand..]. .[.16. A method according to claim 15, wherein the residual strand is acted upon to effect its breakout by nipping the strand as it continues to travel..]. .[.17. A method according to claim 15, wherein the residual strand is acted upon to effect its breakout by wearing it away or cutting it as it continues to travel..]. .[.18. Apparatus for forming yarn having at least two strands combined together including feeding means for feeding two strands from spaced feeding points, twisting means to twist the travelling strands together into a single yarn, and at least one strand breaker means disposed at a fixed location spaced from the normal lines of travel of the strands during use of the apparatus, said feeding, twisting and strand breaker means being so located relative to each other that upon break out of one of said strands the residual strand is allowed to adopt a respective modified line of travel in which the residual strand operatively contacts said strand breaker means at said fixed location..]. .[.19. Apparatus according to claim 18 wherein said strand breaker means is comprised of a pair of cooperating rollers disposed to nip a respective one of said strands in its respective modified line of travel..]. .Iadd. 20. Apparatus for spinning a two-ply yarn in a single operation from two separate running strands, said apparatus having a drafting unit for drawing said strands in spaced relation to one another from separate rovings and having a rotatable spindle for twisting the drawn strands together and for winding thereon the two-ply yarn so formed, the twisting action being such as to form a distinctive convergence point between the two component strands, wherein twist blocking means are provided in the vicinity of the said convergence point so that, when one strand breaks the other is allowed to adopt a modified line of travel in which it is acted upon by said twist blocking means to substantially block the travel of twist to that portion of said other strand between said means and the drafting unit so as to thereby cause said other strand to also break. .Iaddend..Iadd. 21. Spinning apparatus according to claim 20 further including a suction device disposed in the vicinity of said convergence point for picking up broken strands. .Iaddend..Iadd. 22. Spinning apparatus according to claim 20 or 21 further including a pair of guides defining a path of travel for the two-ply yarn, wherein one of the guides, mounted for lateral movement under pressure from an unbroken strand in the absence of the other to allow the unbroken strand to adopt its respective said modified line of travel. .Iaddend..Iadd. 23. Spinning apparatus according to claim 22 further including centering means disposed to act on said guide to reduce its lateral movement with the combined strands due to random jitter or the like. .Iaddend. .Iadd. 24. Spinning apparatus according to claim 20 wherein said twist blocking means comprises a pair of cooperating rollers disposed to nip the strands in their respective modified lines of travel to thereby substantially block the travel of twist along the nipped strand. .Iaddend..Iadd. 25. Spinning apparatus according to claim 24 wherein one of the rollers includes a relieved portion in its curved surface, shaped for allowing intermittent free passage of the travelling combined strands while nipping either strand in the event that it adopts its respective said modified line of travel. .Iaddend..Iadd. 26. A method of spinning a two-ply yarn in a single operation from two separate running strands, comprising drawing said strands in spaced relation to one another from separate rovings and twisting the drawn strands together to form a two-ply yarn, the twisting action being such as to form a distinctive convergence point between the two component strands, wherein one strand breaks the other is allowed to adopt a modified line of travel in which the travel of twist along the strand is substantially blocked so as to thereby cause said other strand to also break. .Iaddend..Iadd. 27. A method according to claim 26 wherein broken strands are picked up by a suction device disposed in the vicinity of said convergence point. .Iaddend..Iadd. 28. A method according to claim 26 or 27 wherein the strands are passed through a guide mounted for lateral movement under pressure from an unbroken strand in the absence of the other to allow the unbroken strand to adopt its repsective said modified line of travel. .Iaddend. .Iadd. 29. A method according to claim 26 or 27 wherein said travel of twist is blocked by nipping the unbroken strand in its modified line of travel. .Iaddend.