Title of Invention

A MELT SPINNING AND WINDING DEVICE WHICH COOLS AND WINDS A MELT SPUN YARN

Abstract

IN/PCT/2001/01617/CHE ABSTRACT "A MELT SPINNING AND WINDING DEVICE WHICH COOLS AND WINDS A MELT SPUN YARN" A melt spinning and winding device which cools and winds a melt spun yarn (Y) spun from a spinneret (41), wherein a cooling device (2) which is arranged below the spinneret (41) comprises of a cooling air introducing portion (7) which surrounds the periphery of the melt spun yarn (Y), an ejector portion which is connected to a lower portion of the cooling air introducing portion and injects compression air around the spun yarn (Y), an air flow guide pipe (9) which is connected to a lower portion of the ejector portion (60) of the air ejector mechanism (8) is having an inner pipe (62) is disposed inside the ejector portion (60), and an outer pipe (63) is disposed outside the inner pipe (62) concentrically, whereby a cooling air which is introduced from the outside to the inside of the cooling air introducing portion (7) is moved in the traveling direction of the spun yarn (Y) so as to increase a speed of the cooling air up to the air flow guide pipe (9) and in which the speed (V2) of the compressed air from the injection opening (65) of the ejector portion (60) is faster than the speed (VI) of the air flow from the inner pipe (62), the pressure of the compressed air is lower than that of the air flow, so that the spun yarn (Y) is curved and deflected toward the boundary layer (101) so that the distance between the constituent filaments is expanded whereby the cooling is enhanced, and a winding device which is arranged below said ejector mechanism (8). Figure 1.

Full Text

TECHNICAL FIELD The present invention relates to a melt spinning and winding device which cools and winds a melt spun yam, and more particularly to a melt spinning and winding device which enables the production of yam without lowering the elongation or increasing the fineness defect even when the take¬off speed is increased. BACKGROUND OF THE INVENTION In general, an undrawn yam or a semi-drawn yam made of synthetic resin is produced in such a manner that a spun yam which is spun from a spinneret using a melt polymer is taken off while being cooled and is wound around a bobbin. Further, as a cooling device which cools the spun yam below the spinneret, a perpendicular-flow type cooling device which flows an air flow in a direction perpendicular to the spun yam has been used. In such a melt spinning and winding device, it has been known that the melt spun yam has a characteristic that when the take-off speed is increased, the molecular orientation in the inside of the spun yam is accelerated so that the elongation at break is lowered. Further, it has been known that when the take¬ off speed of the spun yam exceeds 5000 m/min, the crystallization of the spun is generated due to the acceleration of the molecular orientation. Accordingly, when the semi-drawn yarn which has the large elongation at break is to be produced, the mere increase of the take-off speed has a limit with respect to the enhancement of the productivity. For example, with respect to base yarn for draw-false twisting, it is preferable to use the semi-drawn yarn having the elongation at break of equal to or more than 100 %. However, with respect to such a semi-drawn yarn having high elongation, in the melt spun yarn winding device which is provided with a conventional perpendicular flow type cooling device, when the take¬off speed is set at a high speed which is equal to or more than 3800 m/min, the elongation at break is lowered and the fineness defect is increased whereby a desired semi-drawn yarn cannot be obtained. DISCLOSURE OF THE INVENTION It is an object of the present invention to provide a melt spinning and winding device which can manufacture a semi-drawn yarn without lowering the elongation, at break and or without increasing the fineness defect even when the take-off speed is increased more than that of a conventional device. A melt spinning and winding device of the present invention to achieve such an object is a melt spinning and winding device which cools and winds a melt spun yarn spun from a spinneret, wherein a cooling device which is arranged below the spinneret is comprised of a cooling air introducing portion which surrounds a periphery of the melt spun yarn, an ejector portion which is connected to a lower portion of the cooling air introducing portion and injects compression air around the spun yarn, and an air flow guide pipe which is connected to a lower portion of the ejector portion, whereby cooling air which is introduced from the outside to the inside of the cooling air introducing portion is moved in the travelling direction of the spun yarn so as to increase a speed of the cooling air up to the air flow guide pipe. In this manner, by having the cooling device constituted of the cooling air introducing portion, the ejector portion and the air flow guide pipe so as to move the cooling air in the travelling direction of the spun yarn in the inside of the cooling device and by increasing the speed of the cooling air from the cooling air introducing portion to the air flow guide pipe, it becomes possible to make a solidifying point of the spun yarn present in the inside of the air flow guide pipe whereby the semi-drawn yarn can be obtained without lowering the elongation and increasing the fineness defect while holding the take-off speed at a high speed. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic front view illustrating a melt spinning and winding device of the present invention. Fig. 2 is a perspective view showing a cooling air introducing portion of the melt spinning and winding device shown in Fig. 1. Fig. 3 is a longitudinal cross-sectional view of an ejector portion of the melt spinning and winding device shown in Fig. 1. Fig. 4 is a longitudinal cross-sectional view of another embodiment of an ejector portion used in the present invention. Fig. 5 is a layout view illustrating the layout relationship between a spinneret and a cooling device in the present invention. Fig. 6 is a layout view illustrating the layout relationship between the spinneret and the cooling device in the present invention. BEST MODE FOR CARRYING OUT THE INVENTION In a melt spinning and winding device of an embodiment according to the present invention shown in Fig. 1, numeral 1 indicates a spin beam, numeral 2 indicates a cooling device and numeral 3 indicates winding units. A metering pump 4 is mounted in an upper center portion of the spun beam 1, a plurality of spinning packs 6 are arranged at a lower portion of the spun beam 1, and respective spinning packs 6 mount spinnerets 41 therein. The metering pump 4 distributes a melt polymer supplied from a spinner which is not shown in the drawing into a plurality of pipes 5 and yarns Y are supplied to respective spinning packs 6 at a fixed quantity and are spun from respective spinnerets 41. Cooling devices 2 are respectively provided below the respective spinning packs 6. Further, below the respective spinning packs 6, oil supply guides 19 and the winding units 3 are respectively provided. The spun yarns Y which are spun from the spinnerets 41 are cooled by the cooling devices 2 and thereafter are applied with oil supplied from the oil supply guides 19, and then are wound around the winding units 3. The cooling device 2 is constituted of a cylindrical cooling air introducing portion 7 disposed in the vicinity of the spinneret 41 and an air ejector mechanism 8 which is disposed below the spinneret 41 as a subsequent element. The air ejector mechanism 8 is constituted of an upper ejector portion 60 and a lower air flow guide pipe 9. As shown in Fig. 2, in the cooling air introducing portion 7, an air equalizing cylinder 51 is arranged such that the air equalizing 51 surrounds the spun yarn Y. An inner perforated pipe 52 and an outer perforated pipe 53 which respectively have a large number of apertures 52a, 53a are concentrically arranged outside the air equalizing cylinder 51 with a gap formed between the air equalizing cylinder 51 and these pipes 52, 53. The inner air equalizing cylinder 51 has a wall face which is made of a perforated structure in which a large number of minute ventilation passages are laminated such that they are arranged in the radial direction. The outside air is introduced through this wall of the perforated structure toward the inside spun yarn Y while being equalized. The inner perforated pipe 52 which covers the outside of the air equalizing cylinder 51 is fixedly secured to an upper surface of the duct 11 and the outer perforated pipe 53 which is disposed outside the inner perforated pipe 52 is arranged such that the outer perforated pipe 53 is rotatable relative to the inner perforated pipe 52 about a common axis. To a lower periphery of the outer perforated pipe 53, a flange 10 having an arcuate elongated hole 10a is mounted. A bolt 10b which is fixedly secured to the duct 11 is inserted into the elongated hole 10a of the flange 10 and the outer perforated pipe 53 can be secured by fastening the bolt 10b. When the bolt 10b is loosened and the outer perforated pipe 53 is rotated, the apertures 53a on the outer peripheral surface thereof change their phases relative to the apertures 52a of the inner perforated pipe 52 so that the open area is changed thus enabling the adjustment of an introduction quantity of cooling air. The shapes of the apertures 52a, 53a formed in the inner perforated pipe 52 and the outer perforated pipe 53 are not limited to a circular shape shown in the drawing and may adopt any shape such as an elliptical shape, a slit-like shape or the like. As shown in Fig. 3, the ejector portion 60 of the air ejector mechanism 8 is constituted such that an inner pipe 62 is disposed inside the ejector portion 60, an outer pipe 63 is disposed outside the inner pipe 62 concentrically, and a plurality of equalizing plates 64 are interposed between the inner pipe 62 and the outer pipe 63. The inner pipe 62 is constituted of a pipe which is formed by narrowing the diameter of a lower end of a connection pipe 61 extended from the cooling air introducing portion 7. Further, a plurality of flow equalizing plates 64 have their respective surface directions directed in the radial direction with respect to a common axis of the inner pipe 62 and the outer pipe 63 and arranged parallel to the travelling direction of the spun yarn Y. An injection opening 65 which is formed at outlet sides of the flow equalizing plates 6 4 has an injection direction which makes an angle 6 of 0° to 3° with respect to the travelling direction of the spun yarn Y. The ejector portion 60 is accommodated in and fixedly secured to the common duct 11 together with other ejector portions 60 which are mounted in other spinning packs 6 in the same manner. Compressed air is supplied to the duct 11 from a blower not shown in the drawing through a supply pipe 11a. This compressed air invades into a gap defined between the inner pipe 62 and the outer pipe 63 of each ejector portion 60, is equalized by the flow equalizing plates 64 and then is injected to the periphery of the travelling yarn Y from the injection opening 65. By injecting the compressed air at the ejector portion 60, a negative pressure is generated in the inside of the cooling air introducing portion 7 disposed above the ejector portion 60. Due to the generation of this negative pressure, air in room whose temperature is controlled passes the air equalizing cylinder 51 while being equalized through the apertures 52a of the inner perforated pipe 52 from the apertures 53a of the outer perforated pipe 53 and thereafter is supplied to the periphery of the spun yarn Y disposed inside. The air introduced to the inside of the air equalizing cylinder 51 cools the spun yarn Y as cooling air and further gradually increases a flow speed thereof while flowing downwardly along the spun yarn Y. The cooling air is further accelerated at the ejector portion 60 and flows downwardly into the air flow guide pipe 9. In this manner, the spun yarn Y which moves downwardly along with the cooling air is gradually cooled and the solidification of the spun yarn Y is completed in the air flow guide pipe 9. A bell-mouth pipe 12 is mounted on an outlet opening of the air flow guide pipe 9. This bell-mouth pipe 12 gradually increases an outer diameter thereof downwardly and a large number of apertures are formed in a wall surface thereof. Accordingly, the cooling air which is made to flow downwardly into the air flow guide pipe 9 is decelerated since the cooling air is swelled in the bell-mouth pipe 12. That is, the bell-mouth pipe 12 functions as an air flow decelerating portion. The duct 11 which mounts the ejector portions 60 therein is supported on guide rails 13, 14 which are erected at both sides of the duct 11 by means of cylinders 15, 16 and is engaged with guide rails 13, 14 by way of rollers 17, 18 which are mounted on both sides of the duct 11. When the cylinders 15, 16 are manipulated such that they are extended or retracted, the duct 11 is elevated along the guide rails 13, 14. By elevating the duct 11 in this manner, at the time of performing the melt spinning of yarn, the cooling air introducing portion 7 is held in the state that the cooling air introducing portion 7 is brought into pressure contact with the lower surface of the spin beam 2, while, at the time of performing the thread guard operation or the exchange operation of the spinning pack, the cooling air introducing portion 7 is lowered so that an operation space is opened between the cooling air introducing portion 7 and the lower surface of the spin beam 2. As cylinders 15, 16, either pneumatic cylinders or hydraulic cylinders may be used. With respect to the arrangement of a plurality of spinnerets 41 (spinning packs 6) mounted on the spin beam 1, they are arranged in one row in the embodiment shown in Fig. 1. However, as shown in Fig. 5, a plurality of spinnerets 41 are arranged in two rows, that is, the front and rear rows at a depth side and at a fore side with respect to the operation surface or in a staggered pattern. Due to such an arrangement, even when a larger number of spinning packs 6 can be arranged per one set of spin beam, the total length L of the spin beam 1 can be shortened by holding a given distance d between the cooling devices 2, 2 which' are disposed close to each other. In the same manner, as shown in Fig. 6, a plurality of spinnerets 41 (spinning packs 6) disposed in the inside of the spin beam 1 are arranged in the arcuate shape. Due to such an arcuate arrangement, it becomes easy to set the distance between the respective pipes 5 which supply the melt polymer to respective spinnerets 41 from the metering pump 4 substantially equal whereby the heat history of the polymer can be made uniform and hence, the physical properties of the yarns can be made uniform. According to the above-mentioned melt spinning and winding device of the present invention, the device is characterized in that the cooling air flows in the same direction as the travelling direction of the spun yarn Y in the inside of the cooling device 2 and the flow speed of the cooling air is made low in the vicinity of the spinnerets 41 and is increased gradually toward the air flow guide pipe 9. Such an adjustment of the speed of the cooling air can be performed by the control of the air introduction quantity by the outer perforated pipe 53 at the cooling air introducing portion 7 and the control of a supply quantity of the compressed air at the ejector portion 60. The control of the supply quantity of the compressed air is performed by the pressure control. Due to the change of such a speed of the cooling air, at the downstream of the ejector portion 60, the spun yarn Y and the cooling air are accelerated by the compressed air and the spun yarn Y reaches the solidifying point in the air flow guide pipe 9 by cooling. In the air flow guide pipe 9, since the spun yarn Y is exposed to the cooling air which flows in the same direction, the air resistance is decreased and hence, the stress which is applied to the spun yarn Y becomes small whereby the molecular orientation is suppressed. Accordingly, it becomes possible to hold the elongation at break at a large value by setting the take-off speed at a high speed. To obtain such a suppression action of the molecular orientation, it is preferable to set the total length of the air flow guide pipe 9 to a value which is not less than 10 times and not more than 50 times of the inner diameter thereof. When the total length of the air flow guide pipe 9 is set to a value which is less than 10 times of the inner diameter thereof, it is difficult to always retain the solidifying point in the inside of the air flow guide pipe 9 in a stable manner and hence, there arise irregularities with respect to the elongation of spun yarn. Further, when the total length of the air flow guide pipe 9 is set to a value which is more than 50 times of the inner diameter thereof, the pressure loss in the air flow guide pipe 9 is increased so that the generation of a negative pressure at the upstream side becomes insufficient whereby the cooling of the spun yarn becomes insufficient and brings about the fineness defect. In the above-mentioned adjustment of the speed of the cooling air, when the speed of the cooling air in the vicinity of the spinneret 41 is increased, the turbulence occurs and this turbulence generates the vibration of the spun yarn Y in the midst of the cooling and hence, the fineness defect occurs. As the speed of the cooling air which does not generate the fineness defect, it is preferable to set the speed to 15 to 35 m/min at the downstream portion of the cooling air introducing portion 7 when the fineness of the yarn is 3.7 dtx and to a value which is 1/1.2 to 1/2 times of the above-mentioned speed in the vicinity of the spinneret 41. The speed of the cooling air is made small for the spinning of the yarn having the small fineness and is made large for the spinning of the yarn having the large fineness. Further, it is preferable that the greater the fineness of the yarn, the length of the cooling air introducing portion 7 is elongated. Further, when the pressure of the compressed air at the ejector portion 60 is excessively high, the turbulence occurs and hence, the thread swinging occurs thus giving rise to the fineness defect and the end breakage. Accordingly, it is preferable to set the injection speed at the ejector portion 60 to not more than 3000 m/min. As mentioned previously, it is preferable to have the injection direction of the compressed air injected from an injection opening 65 of the ejector portion 60 to make an angle 9 of 0° to 3° with respect to the travelling direction of the spun yarn Y. It is more preferable to set such an angle 9 to 0°. That is, as shown in Fig. 4, when the angle 9 is set to 0°, since the injecting direction of the injection opening 65 and the axial direction of the inner pipe 62 are in parallel, the air flow of the compressed air injected from the injection opening 65 moves along a boundary layer 101 without being mixed with the air flow which flows into from the inner tube 62. Further, since the speed V2 of the compressed air from the injection opening 65 is faster than the speed VI of the air flow from the inner pipe 62, the pressure of the compressed air is lower than that of the air flow. Accordingly, the spun yarn Y is curved and deflected toward the boundary layer 101 so that the distance between the constituent filaments is expanded whereby the cooling is enhanced. The boundary layer 101 is diffused and disappear toward the downstream of the air flow. The bell mouth pipe 12 which is connected to the lower end of the air flow guide pipe 9 swells the cooling air which descends together with the spun yarn Y and decreases a quantity of cooling air which reaches the oil supply guide 19. Accordingly, the thread swinging at the oil supply guide 19 can be reduced so that adhesion defect of an oil agent can be reduced. Embodiment 1 In the melt spinning and winding device shown in Fig. 1 to Fig. 3, an inclination angle 8 of the compressed air injected from the injection opening 65 with respect to the spun yarn Y was set to 1.5°, the temperature of the compressed air was set to 40°C, the pressure of the compressed air was set to 400 mm aq and the speed of the cooling air was adjusted such that the speed was set to 20 m/min at the upper end of the cooling air introducing portion 7, 30 m/min at the lower end of the cooling air introducing portion 7 and 2300 m/min in the inside of the air flow guide pipe 9 and the melt spinning of polyester multi-filament yarn 133dtx-36f was performed wherein the yarn was taken off at a speed of 4000 m/min. The elongation at break of the obtained polyester semi-drawn yarn was 120 % and the fineness defect (U %) thereof was 0.8 %. Comparison Example 1 Using a melt spinning device which is equipped with a perpendicular-flow-type cooling device, the speed of the cooling air was set to 18 m/min and the melt spinning of polyester multi-filament yarn 133dtx-36f was performed wherein the yarn was taken off at a speed of 4000 m/min. The elongation at break of the obtained polyester semi-drawn yarn was 90 % and the fineness defect (U %) thereof was 0.9 % thus exhibiting the lowering of the elongation at break. Embodiment 2 In a melt spinning and winding device identical with the melt spinning and winding device of the embodiment 1, the speed of cooling air was adjusted such that the speed was set to 22 m/min at the upper end of the cooling air introducing portion 7, 32 m/min at the lower end of the cooling air introducing portion 7 and 2200 m/min in the inside of the air flow guide pipe 9 and the melt spinning of polyester multi-filament yarn 280dtx-48f was performed wherein the yarn was taken off at a speed of 4000 m/min. The elongation at break of the obtained polyester semi-drawn yarn was 121 % and the fineness defect (U %) thereof was 0.9 %. Embodiment 3 Except for the condition that the angle 6 of the injection opening 65 was set to 0°, a polyester multi¬filament yarn 133dtx-36f was produced under the same conditions as those of the Embodiment 1. The elongation at break of the obtained polyester semi-drawn yarn was 118 % and the fineness defect (U %) thereof was 1.0 %. Embodiment 4 Except for the condition that the spun yarn was taken off at 4500 m/min, a polyester multi-filament yarn 133dtx-36f was produced under the same conditions as those of the Embodiment 1. The elongation at break of the obtained polyester semi-drawn yarn was 102 % and the fineness defect (U %) thereof was 0.7 %. Embodiment 5 Except for the condition that the angle 9 of the injection opening 65 was set to 3°, a polyester multi¬filament yarn 133dtx-36f was produced under the same conditions as those of the Embodiment 1. The elongation at break of the obtained polyester semi-drawn yarn was 124 % and the fineness defect (U %) thereof was 1.1 %. As mentioned above, according to the melt spinning and winding device of the present invention, the cooling device is constituted of the cooling air introducing portions, the ejector portions and the air flow guide portions, wherein, in the inside of the cooling device, the cooling air is moved in the travelling direction of the spun yarn and the speed of the cooling air is increased from the cooling air introducing portion to the air flow guide pipe so that it becomes possible to make the solidifying point of the spun yarn present in the inside of the above-mentioned air flow guide pipe whereby the semi-drawn yarn which is free from the lowering of the elongation and the increase of the fineness defect while ensuring the take-off speed at the high speed level can be obtained. INDUSTRIAL APPLICABILITY The present invention is useful particularly when the semi-drawn yarn having the high elongation is manufactured at the high-speed take-off speed in the manufacturing field of the synthetic fiber. WE CLAIM 1. A melt spinning and winding device which cools and winds a melt spun yarn (Y) spun from a spinneret (41), wherein a cooling device (2) which is arranged below the spinneret (41) comprises of a cooling air introducing portion (7) which surrounds the periphery of the melt spun yarn (Y), an ejector portion which is connected to a lower portion of the cooling air introducing portion and injects compression air around the spun yarn (Y), an air flow guide pipe (9) which is connected to a lower portion of the ejector portion (60) of the air ejector mechanism (8) is having an inner pipe (62) is disposed inside the ejector portion (60), and an outer pipe (63) is disposed outside the inner pipe (62) concentrically, whereby a cooling air which is introduced from the outside to the inside of the cooling air introducing portion (7) is moved in the traveling direction of the spun yarn (Y) so as to increase a speed of the cooling air up to the air flow guide pipe (9) and in which the speed (V2) of the compressed air from the injection opening (65) of the ejector portion (60) is faster than the speed (VI) of the air flow from the inner pipe (62), the pressure of the compressed air is lower than that of the air flow, so that the spun yarn (Y) is curved and deflected toward the boundary layer (101) so that the distance between the constituent filaments is expanded whereby the cooling is enhanced, and a winding device which is arranged below said ejector mechanism (8). 2. The melt spinning and winding device as claimed in claim 1, wherein a solidifying point of the spun yarn (Y) is present in the inside of the air flow guide pipe (9). 3. The melt spinning and winding device as claimed in claim 1 or 2, wherein the cooling air introducing portion (7) is provided with an air equalizing cylinder (51) which surrounds the spun yarn (Y). 4. The melt spinning and winding device as claimed in claim 1 or 2, wherein an angle 6 which an injection direction of compressed air in the ejector portion (60) makes with respect to the travelling direction of the spun yarn (Y) is set in a range of 0° to 3°. 5. The melt spinning and winding device as claimed in claim 4, wherein equalizing plates (64) are arranged in the ejector portion (60). 6. The melt spinning and winding device as claimed in claim 4, wherein the injection speed of the compressed air in the ejector portion (60) is set to not more than 3000 m/min. 7. The melt spinning and winding device as claimed in claim 1 or 2, wherein a bell-mouth pipe (12) is mounted on an outlet portion of the air flow guide pipe (9). 8. The melt spinning and winding device as claimed in claim 1 or 2, wherein the length of the air flow guide pipe (9) is set to 10 to 50 times of the inner diameter of the air flow guide pipe (9). 9. The melt spinning and winding device as claimed in claim 1 or 2, wherein the spinnerets (41) are arranged in a plurality of rows and the cooling device (2) is arranged for each spinneret (41). 10. The melt spinning and winding device as claimed in claim 9, wherein a plurality of spinnerets (41) are arranged in two or more rows in the forward and backward direction.

Documents:

in-pct-2001-1617-che abstract duplicate.pdf

in-pct-2001-1617-che abstract.pdf

in-pct-2001-1617-che claims duplicate.pdf

in-pct-2001-1617-che claims.pdf

in-pct-2001-1617-che correspondence others.pdf

in-pct-2001-1617-che correspondence po.pdf

in-pct-2001-1617-che description (complete) duplicate.pdf

in-pct-2001-1617-che description (complete).pdf

in-pct-2001-1617-che drawings.pdf

in-pct-2001-1617-che form-1.pdf

in-pct-2001-1617-che form-18.pdf

in-pct-2001-1617-che form-26.pdf

in-pct-2001-1617-che form-3.pdf

in-pct-2001-1617-che form-5.pdf

in-pct-2001-1617-che others.pdf

in-pct-2001-1617-che pct search report.pdf

in-pct-2001-1617-che pct.pdf

in-pct-2001-1617-che petition.pdf