Simultaneous multiple twisting apparatus

Abstract

In each twisting unit of a multiple twisting apparatus, a two-for-one twisting assembly imparts a first twist to each component yarn while a ring twisting assembly imparts a second twist to .[.a.]. .Iadd.the .Iaddend.doubled first-twisted yarns. A plurality of first twisted yarns are doubled under tension control and the doubled yarn is taken up by a feed mechanism so as to be supplied to the ring twisting assembly under tension control via a yarn passage formed behind the two-for-one twisting assemblies. The two-for-one twisting assemblies are arranged in two alignments along a lengthwise direction of the apparatus. All driving members are driven synchronously at least at a starting period and at a time of stopping the twisting operation.

What we claim is: 
     
       1. A multiple twisting apparatus having at least one twisting unit, comprising a first twisting device provided with at least two two-for-one twisting assemblies, each of said two-for-one twisting assemblies being provided with a first tension control means disposed therein, means for doubling first-twisted yarns withdrawn from said two-for-one twisting assemblies, a second twisting device disposed below said first twisting device for imparting a second twist to a doubled yarn carried from said means for doubling, means for positively feeding said doubled yarn to said second twisting device, a plurality of yarn guides forming a yarn passage behind said first twisting device and forming a yarn passage to said feeding means, and means for driving said first twisting device, said second twisting device and said feeding means. 
     
     
       2. A multiple twisting apparatus according to claim 1, wherein said driving means comprises means for synchronously driving said first twisting device, said second twisting device and said means for feeding during at least a period of commencing and at the time of stopping said apparatus. 
     
     
       3. A multiple twisting apparatus according to claim 2, wherein said means for driving comprises intermediate power transmission mechanisms, and a motor for driving said first twisting device, said means for feeding and said second twisting device by way of said intermediate power transmission mechanisms. 
     
     
       4. A multiple twisting apparatus according to claim 2, wherein said means for driving .Iadd.comprises .Iaddend.a first motor, intermediate power transmission mechanisms coupled to said first motor for driving said means for feeding together with said second twisting device, a second motor, and an intermediate power transmission mechanism coupled to said second motor for driving said first twisting device. 
     
     
       5. A multiple twisting apparatus according to claim 2, wherein said means for driving comprises a first motor, intermediate power transmission mechanisms coupled to said first motor for driving said means for feeding together with said first twisting device, a second motor and an intermediate power transmission mechanism coupled to said second motor for driving said second twisting device. 
     
     
       6. A multiple twisting apparatus according to claim 2, wherein said means for driving comprises a first motor, an intermediate power-transmission mechanism coupled to said first motor for driving said means for feeding, a second motor, and an intermediate power transmission mechanism coupled to said second motor for driving said first twisting device and said second twisting device. 
     
     
       7. A multiple twisting apparatus according to claim 2, wherein said means for driving comprises a first motor for driving said means for feeding, a second motor for driving said first twisting device, a third motor for driving said second twisting device, and separate intermediate power transmission mechanisms coupled to said first, second and third motors. 
     
     
       8. A multiple twisting apparatus having at least two twisting units according to claim 2, wherein said means for driving for said second twisting devices comprises an individual driving motor corresponding to each of said second twisting devices. 
     
     
       9. A multiple twisting apparatus according to claim 2, wherein said means for driving comprises a first belt-drive system having an endless belt for driving spindles of said two-for-one twisting assemblies of all twisting units and a second belt-drive system having an endless belt for driving spindles of said second twisting device of all twisting units. 
     
     
       10. A multiple twisting apparatus according to claim 9, wherein said second belt-drive system comprises a plurality of endless belts coupled to drive said second twisting devices, said second twisting devices being disposed at both sides of said twisting apparatus in facing condition, respectively. 
     
     
       11. A multiple twisting apparatus according to claim 9 wherein said second belt-drive system comprises a plurality of endless belts for driving four second twisting devices, said four second twisting devices being disposed at both sides of said twisting apparatus in such a condition that two of said second twisting devices are disposed at a first side of said twisting apparatus with a predetermined spindle pitch therebetween while the other two second twisting devices are disposed at another side of said twisting apparatus in facing condition to said two twisting devices disposed at said first side. 
     
     
       12. A multiple twisting apparatus according to claim 1, wherein said two-for-one twisting assemblies of all twisting units are arranged in two groups, one of said groups is aligned along a front side line being parallel to a longitudinal direction of said twisting apparatus, the other of said groups is aligned along a rear side line being parallel to said front side line, the angle α between said front side line or said rear side line and a line passing through the axial centers of the nearest two two-for-one twisting assemblies selected from said front side line and said rear side line, respectively, being within a range between 60° and 90°. 
     
     
       13. A multiple twisting apparatus according to claim 1, wherein an angle θ between the upright direction and a spindle axis of each of said two-for-one twisting assemblies being mounted on a bracket of said twisting apparatus is in the range of 0 to 90 degrees. 
     
     
       14. A multiple twisting apparatus according to claim 1, further comprising a second means for controlling yarn tension located between a delivery position of each of.[.,.]. said two-for-one twisting assemblies and said means for doubling, and a third means for controlling yarn tension located between said means for doubling and said means for feeding. 
     
     
       15. A multiple twisting apparatus according to claim 12, wherein said twisting units are disposed on both sides of said apparatus. 
     
     
       16. A multiple twisting apparatus according to claim 9, wherein each of said first twisting devices .[.comprised.]. .Iadd.comprises .Iaddend.a clutch means for simultaneously engaging or disengaging each of said first twisting devices to and from said endless belt of said first belt-drive system independently from other first twisting devices. 
     
     
       17. A multiple twisting apparatus according to claim 14, wherein said third means for controlling yarn tension has a capability to reserve an excess length of yarn in a slackened condition which is created at a time of stopping the twisting operation. 
     
     
       18. A multiple twisting apparatus according to claim 14, wherein said second means for controlling yarn tension comprises a yarn tension detector and a limit switch connected to an actuating mechanism of said driving means, whereby said limit switch is actuated to stop said driving means when said yarn tension detector detects a definite lowered condition of yarn tension. 
     
     
       19. A multiple twisting apparatus according to claim 13, wherein said range is from 0° to 45°. .Iadd. 
     
     
       20.  A multiple twisting apparatus as defined in claim 1 wherein said doubled yarn comprises a strand. .Iaddend. .Iadd.21. A multiple twisting apparatus as defined in claim 1 wherein said doubled yarn comprises a pair of first twisted yarns disposed in close proximity with each other. .Iaddend. .Iadd.22. A multiple twisting apparatus as defined in claim 14 wherein said doubling means, said plurality of yarn guides, and said means for positively feeding said doubled yarn, together, define a common carrying passage for said doubled yarn. .Iaddend. .Iadd.23. A multiple twisting apparatus as defined in claim 20 or 21 further comprising a plurality of two-for-one twisting assemblies disposed in adjacent pairs along the lengthwise direction of said apparatus, one member of each said pair being disposed along a forward line extending in the lengthwise direction of said apparatus and the other member of each said pair being disposed behind said one member and along a rearward lengthwise line parallel to said forward line, a plurality of said second twisting devices being disposed along the lengthwise direction of said apparatus, wherein said means for doubling first-twisted yarns comprise a plurality of doubling yarn guides, each said doubling yarn guide being located above one of said pairs of two-for-one twisting assemblies, the lengthwise distance between adjacent second twisting devices being approximately equal to the lengthwise distance between adjacent yarn guides. .Iaddend. .Iadd.24. A multiple twisting apparatus as defined in claim 23 wherein said pair of two-for-one twisters is inclined at an angle of from 
     
     
        0° to 90° to the upright direction. .Iaddend. .Iadd.25.  A multiple twisting apparatus as defined in claim 24 wherein said angle is approximately 10°. .Iaddend. .Iadd.26. A multiple twisting apparatus as defined in claim 20 or 21 wherein each said second twisting device is in substantial coaxial alignment with one of said two-for-one twisters. .Iaddend. .Iadd.27. A multiple twisting apparatus as defined in claims 20 or 21 wherein a pair of two-for-one twisters are provided, one two-for-one twister of said pair being disposed in front of the other and along a line extending in the lengthwise direction of said apparatus, said second twisting device being in substantial coaxial alignment with said one two-for-one twister. .Iaddend. .Iadd.28. A multiple twisting apparatus as defined in claim 27 wherein a line passing through the axial centers of each member of said pair of two-for-one twisters is generally perpendicularly related to the longitudinal direction of said multiple twisting apparatus. .Iaddend. .Iadd.29. A multiple twisting apparatus as defined in claims 20 or 21 wherein said means for doubling first-twisted yarns withdrawn from said two-for-one twisting assemblies is positioned above said two-for-one twisting assemblies. .Iaddend. .Iadd.30. A multiple twisting apparatus as defined in claim 29 wherein at least a pair of two-for-one twisters are provided, one two-for-one twister of said pair being disposed in front of the other and along a frontal line extending in a lengthwise direction of said apparatus, said second two-for-one twister being disposed along a rearward line parallel to said frontal line, and wherein said mean for doubling first-twisted yarns is located equidistantly from each of said two-for-one twisters in said pair. 
     
     
        .Iaddend. .Iadd.31.  A multiple twisting apparatus as defined in claim 29 wherein said means for doubling is also disposed in front of said plurality of yarn guides and adapted to provide an initial path for said first-twisted yarns withdrawn from said two-for-one twisting assemblies which extends upwardly from said two-for-one twisting assemblies then rearwardly to said plurality of yarn guides. .Iaddend. .Iadd.32. A multiple twisting apparatus as defined in claim 31 wherein said means for positively feeding said doubled yarn to said second twisting device is positioned in front of said plurality of yarn guides, said means for doubling, said plurality of yarn guides, and said means for positively feeding said doubled yarn, together, defining an overall yarn path for said yarn which overall yarn path first extends upwardly from said two-for-one twisting assemblies to said doubling means, and rearwardly from said doubling means to said plurality of yarn guides and thus behind said two-for-one twisting assemblies, then forwardly from said plurality of yarn guides to said means for positively feeding said doubled yarn. .Iaddend. .Iadd.33. A multiple twisting apparatus as defined in claim 32 wherein said yarn passage behind said two-for-one twisting assemblies defines a line which is generally perpendicular to a line defined by that portion of said overall yarn passage which extends forwardly from said plurality of yarn guides to said means for positively feeding said doubled yarn. .Iaddend. .Iadd.34. A multiple twisting apparatus as defined in claim 31 wherein said yarn passage behind said two-for-one twisting assemblies defines a line which is generally perpendicularly related to a line defined by that portion of said overall yarn passage which extends rearwardly from said doubling means to said plurality of yarn guides. 
     
     
        .Iaddend. .Iadd.35.  A multiple twisting apparatus as defined in claim 33 wherein said line defined by that portion of said overall yarn passage which extends forwardly from said plurality of yarn guides to said means for positively feeding said doubled yarn is substantially perpendicularly related to the lengthwise direction of said apparatus. .Iaddend. .Iadd.36. A multiple twisting apparatus as defined in claim 34 wherein said line defined by that portion of said overall yarn passage which extends rearwardly from said doubling means to said plurality of yarn guides is substantially perpendicularly related to the lengthwise direction of said apparatus. .Iaddend. .Iadd.37. A multiple twisting apparatus as defined in claims 20 or 21 wherein said first tension control means is adapted to control tension within the range of 0.005 grams/denier-0.050 grams/denier. .Iaddend. .Iadd.38. A multiple twisting apparatus as defined in claim 14 wherein said second means for controlling yarn tension comprises a tension spring and a yarn feeler adapted to pass underneath said yarn and being connected to said tension spring so as to be biased upwardly thereby. .Iaddend. .Iadd.39. A multiple twisting apparatus as defined in claim 14 wherein said third means for controlling yarn tension comprises, a pair of rotatable guide rollers, a tension spring, and a rotatable intermediate guide roller located intermediate said pair of rotatable guide rollers and connected to said tension spring so as to be biased thereby. .Iaddend. 
     
     
        .Iadd.40.  A multiple twisting apparatus as defined in claim 14 wherein said third means for controlling yarn tension comprises a rod pivotally mounted to said apparatus at a pivot point, and a weight mounted on one end of said rod to bias the opposite rod end upwardly, said opposite rod end being adapted to contact said yarn from the underside thereof. .Iaddend. .Iadd.41. A multiple twisting apparatus as defined in claim 14 wherein said second tension control means is adapted to control tension within the range of 0.035 grams/denier to 0.150 grams/denier. .Iaddend. .Iadd.42. A multiple twisting apparatus as defined in claim 14 wherein said third tension control means is adapted to control tension within the range of 0.070 grams/denier to 0.200 grams/denier. .Iaddend. .Iadd.43. A multiple twisting apparatus as defined in claims 20 or 21, further comprising a second means for controlling yarn tension located between the delivery position of each of said two-for-one twisting assemblies and said means for doubling, and a third means for controlling yarn tension located between said means for doubling and said means for feeding, and wherein said third tension means is adapted to control tension (T 3 ) in such manner so as to be greater than the tension between said delivery position of each of said two-for-one twisting assemblies and said means for doubling (T 2 ), and wherein said second tension means is adapted to control tension (T 2 ) in such manner as to be greater than the tension (T 1 ) within said two-for-one twisting assemblies which tension 
     
     
        (T 1 ) is controlled by said first tension means. .Iaddend. .Iadd.44. A multiple twisting apparatus as defined in claims 20 or 21 wherein the axes of said two-for-one twisting assemblies of said first twisting device and the axis of said second twisting device are substantially located on a same plane, said means for doubling, said plurality of yarn guides, and said means for positively feeding said doubled yarn, together, defining an overall yarn path for said yarn which overall yarn path first extends upwardly from said two-for-one twisting assemblies to said doubling means, and rearwardly from said doubling means to said plurality of yarn guides and thus behind said two-for-one twisting assemblies, then forwardly from said plurality of yarn guides to said means for positively feeding said doubled yarn and said overall yarn path for said yarn is substantially located in said plane. .Iaddend. .Iadd.45. A multiple twisting apparatus as defined in claim 44 wherein said plane is generally perpendicularly related to the longitudinal direction of said multiple twisting apparatus. .Iaddend.