JPS6231087B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a melt spinning apparatus for thermoplastic synthetic fibers such as polyamide and polyester.
The purpose of this is to save energy by significantly reducing the amount of cooling air, and at the same time prevent the occurrence of foreign matter adhering to the mouth surface, adhesion of single fibers, or yarn breakage, and maintain stable quality products and process conditions for a long period of time. An object of the present invention is to provide a melt spinning device that can be held together.

Generally, in melt spinning equipment, a spinning tube consisting of a cooling device and a guide tube is installed next to the spinning pack, and the (single) fiber bundle spun from the spinning pack is passed through the cooling device placed directly below the spinning pack. The spinning tube (cooling device) for short fibers with a large number of spinning holes, for example, is used in the direction of flow of the fiber bundle. On the other hand, a so-called vertical spinning tube is used, which has a closed blowing section that blows out cooling air from the entire cylindrical inner peripheral surface toward the center. Conventionally, such a spinning tube blows out a large amount of cooling air to rapidly cool the spun fiber bundle from the spinning pack directly below the spinning pack, but using a large amount of cooling air has a large impact on cost. Also, from the perspective of recent energy saving measures, there is a need to reconsider the use of large amounts of cooling air in the spinning tube.

From this background, the present inventor developed a melt spinning device,
In particular, we investigated the method for cooling the spun fiber bundles in the spinning tube, and discovered that by cooling the spun fiber bundles in stages, the amount of cooling air blown out from the cooling device could be significantly reduced. As a result of various studies on a device that is suitable for such cooling and can operate stably for a long period of time as a production facility without impairing the process condition or product quality (maintaining the same quality as conventional products), we have developed the present invention. It was achieved.

That is, the present invention provides a melt-spinning apparatus for thermoplastic polymers equipped with a spinning tube having a cooling device and a guide tube, in which a slow cooling tube is disposed between the spinning pack and the cooling device, and a slow cooling tube is provided between the spinning pack and the cooling device. An exhaust port for sucking the gas directly below the pack is provided at an upper position, and fins are formed at least on the upper part of the blowing surface of the cooling device to restrict the blowing direction of the cooling air upward, and an intermediate opening is provided at the lower end of the cooling device. It is characterized by connecting the guide tubes through.

Hereinafter, the present invention will be explained based on the drawings. The figure is a sectional view showing an embodiment of the present invention. In the figure, reference numeral 1 denotes a spin block, into which is inserted a spinning pack 2 incorporating a spinneret plate 3 in which spinning nozzles are arranged in multiple rows circumferentially. A spinning tube 4 is composed of a cooling device 5, an intermediate open tube 14, and a guide tube 16. The cooling device 5 includes an inner cylinder 6, an outer cylinder 7, an upper and lower flange 8 for fixing these,
9, an inlet nozzle 10, etc., and a large number of small holes 11 constituting an air outlet are bored in the inner cylinder 6 almost all around its circumference. Further, at the upper part of the inner cylinder 6, fins 12 in the shape of a truncated conical cylinder are protruded in multiple stages for regulating the blowing direction of the cooling air upward.
13 is a filter made of sintered metal or the like. The intermediate open cylinder 14 is located between the cooling device 5 and the guide cylinder 16 and connects them. A large number of small holes 15 are provided on the entire circumference of the cylinder surface, and a position directly below the cooling device 5 is connected to the outside air. It is designed to communicate. This intermediate open cylinder 14 does not necessarily have to be a substantial cylindrical body, but may be a circular arrangement of rod bodies as long as it forms an open space, or it may be a space without such a shape at all. It may be only. In addition, guide tube 1
6 is made into a substantial cylinder (without holes). 1
Reference numeral 7 denotes an annealing cylinder disposed between the spinning pack 2 and the cooling device 5, which is formed integrally with the collar 18 so as to have approximately the same diameter as the inner diameter of the fin 12, and its upper end is near the lower end of the spinning pack 2. It has reached this point. Further, behind the slow cooling tube 17, a stepped cylinder 19 is integrated with the slow cooling tube 17 to form a stepped annular exhaust chamber 20, and the upper end surface thereof has a large number of small holes (wire mesh may be used). This serves as a perforated exhaust port 21. 22 is a suction nozzle that communicates with suction means such as a vacuum pump or an ejector.

Although the exhaust chamber 20, the exhaust nozzle 21, etc. are integrally formed using the slow cooling tube 17, these may be provided separately or independently, and the exhaust port 21 is not limited to a small hole. A slit or simply an annular opening may be used. Further, the exhaust port may be provided using a spinning pack or a spin block as long as it is located above the slow cooling cylinder 17.

23 is a spacer inserted to fix the slow cooling tube 17 or the exhaust chamber 20.

In the apparatus configured as described above, the fiber bundle Y spun from the spinning pack 2 is cooled and solidified by the cooling air forcibly blown out from the cooling device 5, and then flows into the next intermediate open cylinder 14. It is completely cooled and solidified by a large amount of outside air and flows down.

In this case, the cooling device 5 performs two stages of cooling. That is, the cooling air blown from the upper part of the inner cylinder 6 is regulated by the fins 12 and flows upward, and most of the cooling air in this part crosses the fiber bundle Y while cooling it, but is not shown in the exhaust port 21. Since the suction force (depressurized state) by the suction means is acting, the atmospheric gas directly below the spinning pack 2 is constantly attracted to the exhaust port 21 side and exhausted.

Therefore, most of the cooling air that has crossed the fiber bundle Y slowly rises, reverses itself, crosses the fiber bundle Y again, and is introduced into the exhaust port 21. This ascending, reversing and crossing, or mainly carried out within the area of the slow cooling tube 17,
In this area, the temperature of the cooling air increases due to fiber bundle cooling and heat from spin block 1, spinning pack 2, etc., and the cooling of the fiber bundle immediately after spinning from spinning pack 2 is slowed down to the extent that it solidifies the single fiber surface. It is cold, and the amount of cooling air is halved compared to conventional models. Therefore, adhesion of the single fibers, knealing, thread breakage, etc. can be prevented, and the adhesion of foreign matter to the mouth surface etc. can be suppressed.

The fiber bundle Y whose surface has been solidified in the slow cooling cylinder 17 region then flows down at an increased speed while being drafted along the blowing surface of the inner cylinder 6. Here, the single fiber core portion is directly cooled by the cooling air from the inner cylinder 6 and solidified, but the degree of solidification is gradual and the amount of air may be small, so that no yarn sway occurs. still,
Cooling of the fiber bundle from the slow cooling cylinder 17 to the cooling device 5 is sufficient with a cooling air volume that does not completely solidify the fiber bundle, but only causes surface solidification and partial solidification of the core, and is significantly lower than the conventional air volume. has been reduced.
In addition to reducing the air volume, the length of the air outlet can be shortened by shielding it with a plate, for example, from 1/5 to 1/5.
It is best to reduce it to about 1/3.

After this, the fiber bundle Y is transferred from the intermediate open tube 14 to the guide tube 1.
However, in these areas, the flow rate increases rapidly, and the guide tube 16 becomes depressurized due to the flow of the fiber bundle, so a large amount of outside air flows in from the intermediate open tube 14, and this inflow outside air As a result, the fiber bundle Y is rapidly cooled and completely solidified.

Here, the length of the slow cooling cylinder 17 is usually 50 to 100 m/m.
(excluding the length from the mouth surface to the slow cooling tube 17 of 20 to 40 m/m), and the length ratio with the cooling device 5 (inner tube 6 / slow cooling tube 17) is preferably 2.5 to 5.5. It is better to do so. The fins 12 may be provided over the entire area of the inner cylinder 6, and the inclination angle α is preferably 40 to 80 degrees.

In this way, a slow cooling cylinder is provided directly below the spinning pack, an exhaust port is formed above the slow cooling cylinder, and fins are provided at the top of the inner cylinder, which is the cooling air outlet, to regulate the direction of the cooling air upward. By arranging an open tube at the bottom, it is possible to reduce the amount of cooling air blown from the cooling device to about 1/3 to 1/2 without causing problems such as adhesion of single fibers or yarn breakage. It became. Furthermore, the combination of the slow cooling tube and the exhaust port significantly suppresses the attachment or growth of foreign matter on the spinneret surface compared to conventional devices, making it possible to perform stable spinning.

Depending on usage conditions, size, etc., a cylindrical or conical fluid regulator may be hung from the spinneret holder 3' in the center of the spinning pack 2 for slow cooling of the fiber bundle in the annealing cylinder and for the spinneret. This is preferable from the viewpoint of ventilation of the atmosphere directly below the surface.

As explained above, according to the present invention, stepwise cooling can be effectively performed by combining appropriate means, and the amount of cooling air used in the cooling device can be significantly reduced, which is extremely effective as an energy saving measure. It is effective, and at the same time, it has become possible to obtain products with stable process conditions and constant quality without occurrence of adhesion, yarn breakage, knealing, etc. over a long period of time.

[Brief explanation of the drawing]

The figure is a sectional view showing an embodiment of the present invention. 2... Spinning pack, 4... Spinning cylinder, 5... Cooling device,
6...Inner cylinder, 12...Fin, 14...Middle open cylinder, 1
6... Guide tube, 17... Annealing tube, 20... Exhaust chamber, 21
…exhaust port.

Claims (1)

[Claims] 1. In a thermoplastic polymer melt spinning apparatus having a spinning tube consisting of a cooling device and a guide tube, a slow cooling tube is disposed between the spinning pack and the cooling device, and a slow cooling tube is placed directly below the slow cooling tube at a position above the slow cooling tube. fins are formed at least on the upper part of the blowing surface of the cooling device to regulate the blowing direction of the cooling air upward, and a guide tube is provided at the lower end of the cooling device through an intermediate opening. A melt spinning device characterized by connecting two.