JPS5988907A - Apparatus for melt spinning - Google Patents

Abstract

PURPOSE:An apparatus capable of improving the condition of spinning process and obtainng fibers of good characteristics such as strength and elongation by boring gas discharge holes in a spinning block and inseting a spacer having a passage hole for extruded filaments in delayed quenching zone with a prescribed space left below the undersurface of a spinning pack. CONSTITUTION:An apparatus equipped with a spacer 17 having a passage hole for extruded filaments 16 in close vicinity thereto in a delayed quenching zone 19 to cover the delayed quenching zone 19 with a space (d) of 3-20mm. length left below the undersurface of a spinning pack 2 and furthermore gas discharge holes 7, 6 and 10 in a spinning block 1, the pack 2 and a frame 9 respectively to discharge a hot atmosphere staying just under the spinning pack 2 above the spinning block 1. The above-mentioned apparatus permits the atmosphere just under the surface of a spinneret 18 to be discharged upward and downward in two directions.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention suppresses the generation and growth of foreign matter that accumulates around the nozzle of the spinneret, which is the main cause of poor performance in the spinning process, in bath-melt spinning of medicinal melon bodies, thereby improving the spinning process. The present invention relates to a melt spinning device that improves the tension, produces fibers with less yarn unevenness, and has good strength and elongation characteristics.

Generally speaking, in the melt-spinning of multilayer polymers, foreign substances such as low-molecular weight substances are generated at the same time as the molten polymer is discharged, and these foreign substances accumulate around the nozzle on the spinneret surface and affect the spinning, drawing condition, and yarn. To prevent quality deterioration, foreign matter accumulated on the spinneret surface is periodically removed using a spatula or the like, or the spinneret is replaced, but the cost for this - labor costs, The loss of opportunity for polymer production is considerable, and reducing the frequency of cleaning the spinneret surface and replacing the spinneret has long been an important issue for textile manufacturing engineers.

Various methods have been proposed to suppress the accumulation of foreign matter around the spinneret nozzle, but since the foreign matter is mainly sublimable, a large amount of sublimated matter directly under the spinneret surface has been proposed. It is known that generation and growth of foreign matter deposited on the mouthpiece surface can be suppressed by discharging the atmosphere contained in the vJ' to the outside of the system. As a device to effectively exhaust the atmosphere directly below the spinneret surface, an exhaust hole is provided that penetrates the bottom surface of the spinning pack and the spin block located above it.
A system has been proposed in which exhaust air is passed above the spin block through this exhaust hole by utilizing the chimney phenomenon (Japanese Utility Model Publication No. 52-88-15).

However, with this device, the exhaust is due to the chimney effect, so
The displacement is small and the effect of suppressing foreign matter deposited on the mouthpiece surface cannot be said to be sufficient. If you force suction through a busy exhaust hole or make the exhaust hole huge in order to increase the displacement, it will cause turbulence directly below the mouthpiece surface, worsening the thread unevenness. In addition, as the amount of exhaust air directly under the nozzle surface increases, the temperature immediately below the nozzle surface decreases, resulting in lower strength and elongation of the resulting fibers.
It is not preferable from this point of view as well.

In the conventional method, it has been difficult to suppress foreign matter deposited on the spinneret surface, that is, to improve the quality of the spinning process, and to improve yarn unevenness and strength and elongation properties at the same time.

The present inventors have arrived at the present invention as a result of intensive studies aimed at reducing the amount of foreign matter deposited on the spinneret surface, improving the quality of the spinning process, and obtaining fibers with good yarn unevenness and strength and elongation properties.

That is, the present invention provides a melt spinning apparatus in which a spinning back, a delayed cooling section, and a forced cooling section having a cooling air blowing surface are arranged in order from above, and an exhaust hole for discharging gas located directly below the spinning back to the upper part of the spin block is provided in the spin block. Alternatively, a spacer provided on the spin block and the spinning pack and having a yarn passage hole adjacent to the spun yarn in the delayed cooling section is inserted 3 to 2 times downward from the bottom surface of the spinning puncture to block the delayed cooling section.
It is characterized in that it is arranged with a space of .omm left.

Hereinafter, the present invention will be explained based on the drawings. FIG. 1 is a schematic perspective view showing a specific example of the present invention, and FIG. 2 is a IIIvfr side view.

In the figure, l is a spin block and the spin block l
A spinning pack 2 is installed in the lower part of the machine, and a metering pump 3 is installed to control the upper pressure.

A spinneret 18 is attached to the lower end of the second bag, from which the polymer is spun into yarn. 4 is the actual shaft of the pump, and 5 is a passage for the molten polymer. Reference numeral 6 denotes a plurality of exhaust holes provided in the spinning pack 2, and exhaust holes 7 are provided in the spin block 1 in correspondence with and connected to the holes 6. Incidentally, these holes 6.7 are preferably arranged symmetrically or at equal intervals. Reference numeral 9 denotes a frame fitted to the top four parts 8 of the spin block 1, and the frame 9 is provided with a guide tube 10 at a position corresponding to the JJI' outlet 7 to direct the atmosphere directly below the spinning back to the spin block 1. It is designed to be discharged upward.

11 is a heating chamber using a heat medium, and 12 is a heat-retaining bag. 13
is a two-part shutter (not necessarily a ``JjlJ type'') that prevents the spinning tube cooling air from blowing in the direction of the spinneret surface and secures a delayed cooling section. It is slidably supported by the frame and has a thread passage hole 13a formed in the center. 14 is a spinning tube that blows out yarn cooling air, 15 is a yarn cooling volume, and 16 is a yarn. Reference numeral 17 denotes a spacer according to the present invention, which is made of a metal body and is divided into two parts in the front and the rear like the shutter 13.
a, 17b, a spinning pack 2 and a yarn cooling chamber 1.
The delayed cooling section 19 formed between the spun yarn (bundle) 11) has a yarn passageway formed to be close to and surround the spun yarn (bundle) 11), and has a hollow portion 17C. It is arranged so as to almost fill the delayed cooling section 19 except for the space directly below the mouthpiece surface. The spacer 7 is usually placed on the shutter 13 (it may also be fixed using an appropriate means. In such a device, the yarn 1 discharged from the spinneret 18 is placed on the spacer 17 from a position directly below the spinneret. .It travels through the space of the delayed cooling section 19 surrounded by the shutter 13 and the like, reaches the cooling chamber 15, and is cooled and solidified by the cooling air blown out from the spinning tube 14.

In this case, the inner wall surface of the hollow part of the spacer 17 and the spinneret 18
The distance e from the outermost circumferential (spinning) hole 18' is measured as a distance projected on a horizontal plane and is set to 15 mm or less on the spouting side (l) for cooling. As shown in the figure, when the spinning tube 14 to which the cooling air is supplied from one direction is used for one cycle, the threads l and the like are bent in the direction away from the cooling air blowing surface by the cooling air, so that the inside of the spacer hollow part 17'c is bent. The distance between the wall surface and the outermost peripheral hole 18' of the spinneret is on the opposite side to the cooling air blowing surface (42).
is preferably 30+nm or less, and 20 mm or less in the lateral direction (direction perpendicular to the cooling air blowing direction) (13) to make it as small as possible. Incidentally, the same applies to the yarn passage hole 13a of shutter #3.

In addition, a certain amount of space is required at the position below 1α of the spinning pack 2, and the distance d between the spinning pack 2 and the spacer 17 is preferably 3 to 20 mm. This tends to weaken the effect of the present invention.

The reason why the generation and growth of foreign matter deposited on the mouthpiece surface is suppressed by the device of the present invention as described above is as follows.

The yarn polymer discharged from the spun 1 gold 18 is transported downward by cutting off the surrounding air as an accompanying flow in order to run its own material.

In the case of conventional spinning devices, which have a fairly wide space under the spinneret surface, the air exhausted by the accompanying flow is mostly below the spinneret surface where the yarn running speed is high, and at the critical position directly below the spinneret surface, the yarn running speed is low. Since the flow rate is slow, sufficient accompanying flow is not generated and the accompanying flow has almost no exhaust effect.

However, if the spacer 17 is provided between the spinning pack 2 and the spinning tube 14 as in the present invention, and the space between them is essentially only a yarn running space, the problem occurs in the region below the spinneret surface where the yarn running speed is high. The yarn accompanying flow that is generated independently can be discharged to the outside of the system while also sucking the atmosphere directly below the mouth surface.

However, since the atmosphere directly below the mouth surface is at a high temperature, it is inevitable that there is a certain limit to the ability to discharge downward. If there is an appropriate gap between the bottom surface of the spinning pack 2 and the spacer 17, and if an exhaust hole is installed from the bottom surface of the spinning pack 2 to the top of the spin block 1 through the spin block 1, Since the yarn accompanying flow mainly exhausts the air on the upper surface of the spacer 1, the atmosphere directly below the spinneret surface becomes swamped on the lower surface of the spinning back 1 and first diffuses laterally, and some exhaust holes (6, 7 degrees 10) is exhausted to the upper side of the spin block 1, and the rest is swamped on the upper surface of the spacer and is exhausted toward the spinneret surface by the yarn accompanying flow.

In other words, an air flow is formed under the spinneret surface, and some of it is exhausted in two directions, one above the spin block and the other toward the spinning tube, so the exhaust effect is significant. , the accumulation of foreign matter on the mouthpiece surface is effectively suppressed.

This effect can be achieved by simply installing the exhaust hole and installing the spacer! If you go to I+, V is extremely large, so it can be said to be an innovative means of exhausting the atmosphere under the face of the mouthpiece.

” As is clear from this explanation, in order to obtain this effect, it is preferable that the distance between the inner wall surface of the spacer and the yarn bundle be as narrow as possible, and as described above, this appropriate distance is
It is better to make it 15mm or less.

Further, it is necessary that there be an appropriate distance between the spinning back F surface and the upper end surface of the spacer, and according to the experimental results, as described above, a distance of 3 mm or more and 20 mm or less is appropriate.

Furthermore, in the area where the polymer is in a fluid state directly on the mouthpiece surface, which is the most important area for yarn unevenness, the air flow is rectified by the yarn accompanying flow, and there is no space other than the thread running space under the mouthpiece surface. Since there is no unnecessary space, there is no disturbance of the atmosphere in this area due to the howling of the spinning tube cooling wind, etc., which has the effect of reducing yarn unevenness.

Furthermore, generally when the atmosphere under the mouth surface is exhausted, the ambient temperature under the mouth surface decreases, and the strength and elongation of the fibers decreases, but in the present invention, the discharged polymer on the mouth surface "F", back,
Because the spacer is installed in a high-temperature atmosphere with heat radiation from a cock, etc., the spacer is heated to a high fjAVc.
1. The yarn is kept warm during this period due to its radiant heat effect, etc.
The strength and elongation of the fibers does not decrease, but rather improves.

As described in detail above, the apparatus of the present invention suppresses the generation and growth of foreign matter that accumulates around the nostle of the spinneret to a level of 1", dramatically improves the quality of the spinning process, and improves yarn unevenness of 2 or more. This device provides equipment 1 for producing fibers with good elasticity properties, and in particular, it satisfies both the suppression of foreign matter deposited on the spinneret surface, which was considered to be a contradictory phenomenon in the past, and the improvement of yarn unevenness and strength and elongation properties. It can be said that this is a revolutionary bath melt spinning device.

Next, examples will be shown to further specifically explain the effects of the present invention.

Example 1 Polyethylene terephthalate having an IuM viscosity (measured at 35°C in 0-chlorophenol) of 0.635 was prepared using a spinning device having a spinning tube from which cooling air was blown from one direction as shown in Figures 1 and 2. Melt spinning was performed at a spinning speed of x zoom/min to obtain a yarn of 50 denier/36 filaments (measured after stretching). In this case, the exhaust hole (guiding hole 6,
Discharge hole7. A spinning test was conducted by changing the guide cylinder 10), the size of the spacer, and the distance d between the lower surface of the spinning bag and the upper surface of the spacer. The results are shown in Table 1.

In addition, the yellowness of the iA extended cooling section is 100++nu, and the cooling air volume is -
兇一 is 4m'/min.

Table 1 8 is a comparative example.

At this time, the inner wall surface of the spacer and the outer peripheral hole (
Pitch circle: 50 cm) and horizontal distance l from the cooling air outlet side (l
,) is 1'Omm, the opposite side (l,) is 25mm, and the horizontal direction (l,) is 15n+m. The quality of the spinning process is expressed by the fact that if yarn breakage occurs twice or more in 8 hours, the IJ alloy surface will be cleaned, and 1-1 average spinneret 1 stream/# sweeping'' υJ (unit: 2 days). In addition, the yarn physical properties were measured using a drawn yarn, and the dyeing spots were 1! according to the 5-point method. A score of 3.5 or higher is considered a passing level, but a trade mark is preferable.

A pass level for u% is o, r% or less, but the lower the value, the more preferable it is.

From the above results, it can be seen that the combination of the lid pores and the spacer significantly improves the spinning process condition and improves the yarn quality compared to the case of spinning alone.

夾JA′lj　+9142 Melt spinning was carried out under exactly the same conditions as in Example 1.

World 1 - Due to various changes in the shape of the spacer, the gap between the upper surface of the spacer and the spinneret and the outer peripheral hole is 1, J2. J.

changed.

The results are shown in Table 2.

2nd Clothes ``To'' (Note) Level 2.6 is an example, Level 1.J, 4
．． 5 is a comparative example. At this time, the upper end surface of the spacer and i
The gap d between the t-back and the lower surface was 1 (k = 1 mm).

[Brief explanation of drawings]

FIG. 1 is a schematic perspective view showing a specific example of the present invention. FIG. 2 is a longitudinal section 110 of FIG. 1. l.Subiso block 2...Spinning bag 6...Kanki Ill cotton hole 7...Discharge hole 10...Guide cylinder 1: (
... Shutter 14 ... Spinning cylinder] 5. Cooling section 1
6... Yarn 17... Spacer 1B... Spinneret 19... Delayed cooling section 'Xl'

Claims (1)

[Claims] In a melt-spinning apparatus in which a spinning pack, a delayed cooling section, and a forced cooling section with a cooling air blowing surface are arranged from above, an exhaust hole for discharging the gas located directly below the spinning bank above the spin block is connected to the spin block or A spacer provided in the spin block and the spinning pack and having a yarn passage hole adjacent to the spun yarn in the delayed cooling section is used for delayed cooling.
A melt spinning apparatus characterized in that a space of 3 to 20 mm below the bottom surface of a spinning back is left so as to close fB.