JPS5813645B2 - Youyuuboshisouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to melt spinning equipment, and more particularly to a melt spinning equipment with an inert gas supply to reduce spinneret fouling.

Usually, when thermoplastic high polymers (hereinafter referred to as polymers) such as polyamides and polyesters are melt-spun, volatile low polymers are released from the spun polymer stream.

As is well known, these low polymers adhere to the surface of the spinneret, deteriorate through oxidation, and cause fouling of the spinneret.This fouling of the spinneret causes the spun yarn to twitch or buckle. Spinning becomes impossible.

Therefore, when melt spinning is carried out industrially, conventionally, in order to extend the continuous spinning period, an inert gas blowing device is placed above the yarn path area near the spinneret, and a low polymer suction device is placed below. A device is provided to seal the spinneret surface with an inert gas (e.g., nitrogen, helium, carbon dioxide, water vapor, etc.) from the former device to make it difficult for the low polymer to adhere to the spinneret surface and to remove the deposited low polymer. The latter device suppresses oxidative deterioration of the polymer, and the gas near the spinneret, which contains a large amount of volatile low polymer, is sucked out of the system and the low polymer adheres to the surface of the spinneret. I am restrained from doing so.

The present inventor investigated the flow of gas under the spinneret near the spinneret in such a conventional melt spinning apparatus, and when projecting the flow state onto the spinneret surface, it was found that the inert gas The low polymer is sucked toward the periphery of the nozzle, and since the flow directions of the two are different from each other, the flow of the inert gas is disturbed by the flow of the low polymer, and the inert gas It has been found that the reliability of sealing the bottom surface of the spinneret is not sufficient.

The present invention has been made through extensive research in order to eliminate the above-mentioned drawbacks and to provide a melt spinning device equipped with an inert gas supply section that can more reliably seal the bottom surface of the spinneret with inert gas than conventional devices. This is the result.

That is, the present invention provides an inert gas introduction passage in a spinneret that extends from the periphery of the spinneret to the center thereof, extends substantially perpendicularly to the lower part of the spinneret, and opens at the center of the lower part of the spinneret. At the same time, a screw having a substantially T-shaped cross section and a threaded leg is inserted into the inert gas introduction passage in a portion substantially perpendicular to the bottom surface of the mouthpiece. The screw is inserted so that there is a narrow gap between the inner wall of the introduction passage and the leg of the screw, and the head of the screw is located below and facing the opening of the inert gas introduction passage. A melt spinning apparatus characterized in that a leg of a screw is screwed to the bottom of the inert gas introduction passage visible from the opening, and a low polymer suction device is provided surrounding the yarn path area near the mouthpiece. It is.

The present invention will be described below with reference to the drawings.

FIG. 1 is a longitudinal sectional view of the vicinity of the spinneret of the melt spinning apparatus according to the present invention.

In the figure, 1 is a spinning block, 2 is a spinneret pack body, and this spinneret pack body incorporates a spinneret 4 with spinning holes 3, a distribution plate 5, a wire mesh, a filter medium (not shown), etc. Configure the base pack.

An inert gas introduction passage 6 is bored in the mouthpiece 4 .

Specifically, the inert gas introduction passage 6 extends from the periphery of the cap to the center, extends substantially perpendicularly to the bottom surface of the cap, and opens at the center of the bottom surface of the cap. There is.

The aperture is indicated by 7.

In addition, an inert gas introduction passage (hereinafter abbreviated as ``Tsho (A)'') that is substantially orthogonal to the bottom surface of the cap.
A screw 9 having a substantially T-shaped cross section and having threads 8 on the leg L is inserted therein according to the invention.

That is, the screw 9 has a narrow gap S between the inner wall of the passage (A) and the leg part L of the screw, and the head H of the screw is located below the opening 7 of the passage (A). The leg portion L of the screw is inserted into the passage (A) so as to face the opening 7, and the leg portion L of the screw is screwed into the bottom of the passage (A) that is visible from the opening.

Reference numeral 10 denotes an inert gas supply pipe, which has a flexible structure and communicates with the inert gas introduction passage 6 in the cap 4 through a conduit 11 bored in the cap pack body 2. are doing.

Solid arrows indicate the inert gas feed flow.

12 is a low polymer suction chamber provided so as to surround the yarn path area near the spinneret; 13 is a low polymer suction port;
14 is a discharge pipe for discharging the low polymer from the suction chamber 12 to the outside of the system, and these low polymer suction chambers 12
, a low polymer suction port 13 and a discharge pipe 14 constitute a low polymer suction and removal device 15.

The dashed arrow indicates the suction flow of the low polymer, and 16 is a spinning tube equipped with a cooling air blower (not shown).

The distance d between the head H of the screw and the spinneret surface is 10 m.
The width of the narrow gap S between the inner wall of the passageway (A) and the leg portion L of the screw at the opening 7 on the lower surface of the spinneret is preferably less than m (particularly preferably 1 to 3 mm). is preferably 0.5 to 2 mm.

Further, the narrow gap S is not unevenly distributed on one side of the leg portion L of the screw,
It is preferable to form an annular gap of uniform width surrounding the leg portion L of the screw.

FIG. 2 is a perspective view of the screw 9 used in the device of FIG.

3 and 4 are perspective views showing other examples of screws that can be used as the screw 9. FIG.

In the screw shown in FIG. 3, a plurality of grooves are carved along the axial direction in the main part of the leg L of the screw, which has a diameter equal to or less than the diameter of the opening 7 on the lower surface of the spinneret. In the screw shown in FIG. 4, a plurality of annular grooves are carved in the main part of the leg portion L of the screw, each having a diameter smaller than the diameter of the opening 7.

As the screw 9, it is also possible to use one in which a multi-thread thread groove is carved in the main part of the leg portion L of the screw shown in FIG.

If the latter two of the screws are used, the inner wall of the inert gas introduction passage (A) in the spinneret 4 and the leg portion L of the screw 9
The flow of inert gas passing through the space S is buffered by the many convex portions on the leg L, and becomes extremely uniform compared to when the previous two are used.

It is preferable that the low polymer suction port 13 is arranged in a ring shape so as to surround the yarn path area near the spinneret.

Moreover, the distance D from the spinneret surface position of the suction port 13 is
The angle between the horizontal line and the line connecting the center of the opening T on the bottom surface of the spinneret and the center of the suction port 13 is 00 to 30° (
It is particularly preferable to set the angle to 15° or less.

According to the apparatus of the present invention as described above, the inert gas is blown out from the narrow gap that is not closed by the leg portion L of the screw 9 in the opening 7 at the center of the lower surface of the spinneret. After colliding with the spinneret, it flows along the lower surface of the spinneret toward its periphery while sealing the spinneret, and unlike the conventional device, the low polymer suction device 15 sucks and removes the low polymer from the lower part of the spinneret. Since the flow direction is the same as the direction of the air flow, the former flow is not disturbed by the latter flow, and the spinneret can be reliably sealed with inert gas.

Therefore, according to the apparatus of the present invention, the continuous service life of the spinneret can be significantly extended compared to the conventional apparatus.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a longitudinal sectional view of the vicinity of the spinneret of the melt spinning apparatus according to the present invention, and FIGS. 2 to 4 are perspective views of three examples of screws 9 suitable for use in the present invention. . 1...Spinning block, 2...
Spinneret pack body, 3...Spinning hole, 4...
Spinneret, 6... Inert gas introduction passage, 7...
...Opening, 8...Screw thread, 9...
- Screw, L...leg of screw 9, H...゜゜head of screw 9, 15...low polymer suction device.

Claims (1)

[Claims] 1. An inert gas introduction passage is formed in the spinneret so as to extend from the periphery of the spinneret to the center, and from there extend substantially perpendicularly to the lower surface of the spinneret and open at the center of the lower surface of the spinneret, and A screw having a substantially T-shaped cross section and a threaded leg is inserted into the inert gas introduction passage in a portion substantially orthogonal to the lower surface of the base, and is connected to the inner wall of the inert gas introduction passage and the screw. The leg of the screw is inserted into the opening so that there is a narrow gap between the leg and the leg of the inert gas introduction passage, and the head of the screw is positioned below and facing the opening of the inert gas introduction passage. A melt spinning apparatus characterized in that a low polymer suction device is provided which is screwed onto the bottom of the inert gas introduction passage visible from the top and surrounds a yarn path area near the spinneret.