JP2002038328A - Apparatus for melt spinning - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus for melt spinning capable of preventing unevenness of fineness and ununiform cooling caused by a yarn sway due to an increase in a yarn accompanying air flow caused by an increase in number of holes and a spinning rate. SOLUTION: This apparatus for melt spinning has elements of (A) a cooling and spinning chimney for blowing a cooling air in the direction crossing a spun multifilament yarn and cooling the spun multifilament yarn (B) an air supplying and straightening member which is installed at the upper part of the cooling and spinning chimney and supplies a straightened cooling air, (C) a suction air straightening member which is arranged oppositely to the air supplying and straightening member with the spun yarn between and sucks a straightened air from the outside to the inside of the cooling and spinning chimney and (D) an exhaust air straightening member which exhausts a part of an air flow flowing down in the cooling and spinning chimney to the outside of the chimney and is laid right under the suction air straightening average.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a melt spinning apparatus for melt spinning fibers made of thermoplastic synthetic resins such as polyester and nylon.

[0002]

2. Description of the Related Art Generally, in melt-spinning a fiber made of a thermoplastic synthetic resin such as polyester or nylon, a molten thermoplastic polymer is discharged from a spinneret and cooled by a cooling air flowing in a direction across a group of spun yarns. After cooling, stretching and drawing are performed.

[0003] As a cooling means of such a melt spinning,
Conventionally, a cooling gas is blown from one side surface of the spun yarn, and after blowing the cooling gas substantially orthogonally to the spun yarn, the gas is discharged from a surface opposite to the cooling gas blowing surface. 2. Description of the Related Art There are widely used two types of so-called horizontal spinning cylinders and so-called cylindrical spinning cylinders in which a cooling gas is blown from all around the spun yarn. In particular, the former horizontal blowing spinning cylinder has a good workability because the opposite surface facing the cooling gas blowing surface is open,
It is often used for melt spinning of multifilaments for clothing having a relatively small number of single fibers.

[0004] In recent years, there has been an increasing demand for ultrafine fibers having a small single fiber fineness as materials for high value-added products such as high-grade clothing, and it has become necessary to spin them using a multi-hole spinneret. However, in such a multi-hole spinning, in the above-mentioned spinning cylinder, in the process of cooling and solidifying the spun yarn, the cooling is likely to be uneven between the single fibers.
The non-uniformity of the cooling causes the adhesion of the yarn between the single fibers constituting the multifilament yarn and the variation of the cross-sectional shape, causing a process trouble such as yarn breakage, and a fineness unevenness (u) in the length direction. % Unevenness), spots and the like, and it was difficult to obtain an ultrafine multifilament yarn having sufficient quality.

In recent years, the spinning speed has been increased for reasons such as an improvement in productivity. However, the airflow accompanying the running spun yarn has been increased due to this. The accompanying airflow is also a major cause of the yarn sway of the spun yarn.

In order to solve such a problem, various studies have been made in the past. For example, Japanese Patent Application Laid-Open No.
No. 107 discloses an arrangement of polymer discharge holes formed in a spinneret to eliminate a cooling difference between a spun yarn on a blowing side and a non-blowing side of a cooling wind, and a cooling wind is applied to a spun yarn. It has been proposed to improve the passage of the cooling air so as to easily pass between the strips, thereby eliminating the uneven cooling.

[0007] However, in this method, no consideration is given to the increase in the accompanying airflow due to the increase in the number of holes or the speed, and the occurrence of fineness unevenness caused by the yarn sway caused by the increase. In multi-hole spinning of 90 holes or more and high-speed spinning of 2500 m / min or more,
The yarn sway becomes remarkable.

In Japanese Patent Publication No. 59-40923 and Japanese Patent Application Laid-Open No. 63-145407, a straightening plate is provided along the running direction of a yarn group, or a straightening plate is provided to face a cooling air blowing side. A method has been proposed in which the outside air is sucked in through the straightening plate provided to eliminate the disturbance of the cooling air, to achieve uniform cooling of the spun yarn, and to eliminate unevenness in the fineness of the multifilament yarn. ing.

However, even in this method, any consideration is given to the yarn turbulence induced by the increase in the accompanying airflow due to the multi-hole operation and the increase in speed, and the ease of passing the cooling air between the single fibers. Therefore, it is not enough to reduce the occurrence of yarn breakage and unevenness in fineness.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above prior art, and the problems to be solved by the present invention are as follows. That is, when a cooling air is blown across the spun multifilament yarn to blow the multifilament yarn to cool and solidify the melted multifilament yarn, unevenness or irregularity of fineness mainly caused by yarn sway of the yarn is obtained. An object of the present invention is to provide a melt spinning device that can prevent uniform cooling.

[0011]

According to the study of the present inventors, it has been found that the above-mentioned object of the present invention can be achieved by a melt spinning apparatus having the following components A to D. A. A cooling spinning tube that blows cooling air across the spun yarn to cool the spun multifilament yarn. B. An air supply rectifying member provided at an upper portion of the cooling spinning cylinder to supply rectified cooling air; C. An air intake rectifying member that is provided to face the air supply rectifying member with the spun yarn interposed therebetween and that sucks in external air rectified from the outside to the inside of the cooling spinning cylinder; D. An exhaust rectifying member provided immediately below the intake rectifying member for exhausting a part of an airflow flowing down in the cooling spinning cylinder to the outside of the cylinder;

[0012]

Embodiments of the present invention will be described below in detail. FIG. 1 is a side view schematically illustrating a melt spinning apparatus that exemplifies the present invention, wherein Y is a spun yarn composed of multifilaments, 1 is a spin pack, 2 is a multi-hole spinneret, 3 is an updraft blocking member,
4 is a cooling air supply chamber, 5 is a cooling air pressure equalizing member, 6 is an air supply rectifying member, 7 is an intake rectifying member, 7 'is an exhaust rectifying member, 8
Denotes a yarn focusing guide, and 9 denotes a cooling spinning cylinder. Here, the intake rectifying member 7 and the exhaust rectifying member 7 'are
It is provided opposite to the air supply rectifying member 6 with the spun yarn Y interposed therebetween, and has a role of sucking and exhausting the external air rectified from the outside to the inside of the cooling spinning tube 9. Also,
The ascending airflow blocking member 3 is provided so that cooling air does not enter the slow cooling zone immediately below the spinneret 2.
In the figure, the line segment having an arrow indicates the flow direction of the cooling air (flows in the direction of the arrow) so that the flow of the cooling air can be easily visually grasped.

In FIG. 1, L1 is a space between the air supply rectifying member and the ascending airflow blocking member, and the space is set to 10 to 30.
It is preferable to set the cooling air supply hole as a range of mm,
In particular, it is possible to blow a cooling air having a wind speed about twice that of the cooling air supplied from the holes through the air supply rectifying member, and the spun yarn can be rapidly cooled immediately below the place where the upward airflow blocking member is installed. Therefore, it is preferable because yarn sway is reduced and unevenness of fineness due to yarn sway is reduced.

L2 is a space between the intake air flow rectifying member and the upward air flow blocking member, and when there are multiple holes exceeding 150 holes, the upper end of the opposed air flow rectifying member and the upward air flow blocking member are provided. The outside air is also taken in from the space between the two, and the yarn sway increases, and the fineness unevenness tends to increase. Therefore, it is preferable to make the distance as small as possible at the interval of 20 mm or less, and it is particularly preferable that the distance be substantially zero.

L3 and L4 are installation lengths when the air intake rectifying member installation area is divided into two areas, and the apertures in these areas may be the same or different. The aperture d1 of L3 is set to 4.7 mm or less, preferably in the range of 2.0 to 4.7 mm, and the aperture d2 of the other lower region is set to 1.
5 to 2.5, preferably 1.8 to 2.2, and the length L3 of the upper region is 20 to 80 mm, especially 20 to 80 mm.
The range of 50 mm is used in order to reduce the yarn sway by inhaling the cooling with better rectification degree than the external air, and maintaining the appropriate yarn tension by increasing the entrained flow by inhaling the appropriate external air from the L4 region. Is preferred. The length of L4 can be changed as appropriate depending on the type of spun yarn, but usually the length of L4 is
+ L4 300 to 700 mm, especially 400 to 600 mm
Is appropriate.

L5 is the length of the area where the exhaust air rectifying member is installed continuously below the place where the intake air rectifying member is installed. As shown in FIG. Equivalent to a place to exhaust. Therefore, if the aperture in this area is too small or blind, the accompanying flow associated with the spun yarn will cause the yarn to sway when traveling down the cooling spinning cylinder, deteriorating the quality. It will be easier to make
The aperture d3 in this area is 1.5 to 2.
It is preferably in the range of 5 times, especially 2.0 to 2.5 times, and the length of this region is preferably in the range of 300 to 700 mm, especially 400 to 600 mm. In particular, when the spinneret is a multi-hole having 150 holes or more, a high-speed tangential flow near 10 m / sec is accompanied in the vicinity of the yarn focusing guide. And the quality is easily deteriorated due to the wind flowing backward through the spinning cylinder.

The cooling air pressure equalizing member 5 is preferably made of a member such as a wire mesh filter or a gas-permeable sintered metal that generates a pressure loss when the cooling air passes. Because of this, in the cooling air blowing section of the cooling air supply chamber 4, the distribution of the blowing pressure, the wind speed, the air volume, etc. of the cooling wind is adjusted to a profile corresponding to the spinning speed and the spinning conditions such as the brand of the spun yarn. Because it can be controlled. The cooling air controlled to such a preferable profile is supplied from the air supply rectifying member 6 provided at the upper part of the cooling spinning tube 9 and supplying the rectified cooling air to the spun yarn Y in the cooling spinning tube 9. Supplied in a transverse direction. In addition, a blind plate (not shown) may be provided below the air supply rectifying member so that the blowing distance of the cooling air can be adjusted in accordance with the spinning conditions. Therefore, the lengths of the blind plate and the air supply flow regulating member in the yarn traveling direction can be adjusted to each other.

In the melt spinning apparatus configured as described above, the yarn Y spun from the spinneret 2 attached to the spinning pack 1 is supplied from a rectifying member such as a honeycomb. It is cooled and solidified by the cooling air supplied from the member 6 in the direction crossing the spun yarn Y. Then, although not explicitly shown here, after the oil agent is applied as required, the yarn is collected by the yarn collecting guide 8 and the yarn is entangled (not shown). ). At this time, the cooling air supplied across the spun yarn Y flows downward together with the airflow accompanying the traveling yarn Y, thereby increasing the dynamic pressure of the cooling air.
The static pressure in the cooling spinning cylinder 9 decreases. Therefore, the outside air rectified via the intake air rectification member 7 flows into the cooling spinning cylinder 9, and the spun yarn Y is also cooled from this direction.
In addition, the installation length of the intake air flow regulating member 7 may be set as appropriate as appropriate in accordance with the spinning conditions. For example, in melt spinning of polyester, it is preferable that the effective length is 300 to 700 mm along the running direction of the spun yarn Y.

As described above, the air supply rectifying member 6
The cooling air that has flowed into the cooling spinning tube 9 from the air intake rectifying member 7 and gathers toward each other below the cooling spinning tube 9, and the wind speed increases. For example, at the position of the convergence guide 8 shown in FIGS. 1 and 2 where the cooling of the spun yarn Y has already been completed, the wind speed may reach 10 m / min. Since such an air current is a major cause of the yarn sway of the spun yarn, it is necessary to quickly discharge the air to the outside of the cooling spinning cylinder 9, and therefore, as in the present invention,
In order to exhaust a part of the airflow flowing down in the cooling spinning cylinder 9 to the outside of the cylinder without disturbing the airflow, it is necessary to provide an exhaust rectification member 7 ′ directly below the intake rectification member 7.

At this time, the installation length of the exhaust gas rectifying member 7 'is not particularly limited as long as it can effectively fulfill its function. However, in spinning polyester, the effective length is 300-1000.
mm is preferable. By doing so, it is possible to suppress the occurrence of yarn wobble, and to perform stable spinning.

Next, FIG. 2 is a front view of the apparatus illustrated in FIG. 1, which is schematically simplified. As can be seen from this figure, in this embodiment, a large number (six weights) of spinnerets 2 are arranged side by side in a row in a spin pack 1. In particular, such a multi-spindle spinneret 2
In the above, since the spun yarn Y traveling downward does not exist on both side ends of the spun yarn Y having six weights, an upward airflow is generated in a direction opposite to the traveling direction of the spun yarn Y. I do. Since the generation of such an upward airflow obviously disturbs the cooling air in the cooling spinning tube 9, it is preferable to quickly discharge the cooling air from the cooling spinning tube 9.

[0022]

As described above, according to the melt spinning apparatus of the present invention, even in the case of spinning a multi-hole, multi-hole, ultra-fine multifilament yarn or high-speed spinning, the accompanying airflow can be increased. In this way, it is possible to easily control the occurrence of yarn sway and the spinning tension. In addition, it is possible to improve the passage of the cooling air between the single fibers, and to eliminate uneven cooling of the yarn group and the occurrence of yarn sway due to the disturbance of the cooling air. Also, there is an extremely great effect that a good ultra-fine multifilament yarn without breakage can be stably spun.

[Brief description of the drawings]

FIG. 1 is a schematic side view schematically illustrating a melt spinning apparatus of the present invention.

FIG. 2 is a schematic front view illustrating a simplified melt spinning apparatus of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 spinning pack 2 spinneret 3 rising airflow blocking member 6 air supply rectifying member 7 intake rectifying member 7 ′ exhaust rectifying member 8 yarn focusing guide 9 cooling spinning tube Y spinning yarn

Claims (5)

[Claims] 1. A melt spinning apparatus having the following components A to D: A. A cooling spinning tube that blows cooling air across the spun yarn to cool the spun multifilament yarn. B. An air supply rectifying member provided at an upper portion of the cooling spinning cylinder to supply rectified cooling air; C. An air intake rectifying member that is provided to face the air supply rectifying member with the spun yarn interposed therebetween and that sucks in external air rectified from the outside to the inside of the cooling spinning cylinder; D. An exhaust rectifying member provided immediately below the intake rectifying member for exhausting a part of an airflow flowing down in the cooling spinning cylinder to the outside of the cylinder; 2. The opening d1 in the region from the upper 20 to 80 mm of the intake air flow regulating member is 4.7 mm or less, and the ratio (d2 / d1) between the openings d2 and d1 in the other lower region is 1.5 to 2. .
The melt spinning apparatus according to claim 1, wherein 3. The melt-spinning apparatus according to claim 1, wherein a ratio (d3 / d2) between the openings d3 and d2 of the exhaust flow regulating member is 1.5 to 2.5. 4. An ascending airflow blocking member for blocking an ascending airflow is provided at an upper end of the air supply rectifying member and the intake air rectifying member, and 10 to 30 is provided between the installation surface of the air supply rectifying member and the ascending airflow blocking member.
The melt spinning device according to any one of claims 1 to 3, wherein a supply hole for supplying cooling air at an interval of mm is provided. 5. The melt-spinning apparatus according to claim 4, wherein the distance between the installation surface of the intake air flow regulating member and the upward airflow blocking member is 20 mm or less.