JPH11286823A - Melt spinning apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a melt spinning apparatus capable of preventing the change of an atmosphere temperature in a heating column by an air current accompanied by traveling yarn and spinning yarn having excellent qualities. SOLUTION: This apparatus supplies a heated air 6 from a heated air sending means 4 to a heating column 3 installed right below a spinneret 1 so as to enclose a spun yarn group 2 extruded from the spinneret 1. Consequently the static pressure in the heating column is made higher than that at the downstream part of the heating column 3 so as to prevent a cold air from flowing into the heating column.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a melt spinning apparatus for melt spinning synthetic fibers such as polyester and polyamide.

[0002]

2. Description of the Related Art In general, when a thermoplastic polymer such as polyester or polyamide is melt-spun, a cooling air is blown onto a spun yarn running in a spinning tube provided below a spinneret to cool the yarn. Solidification has been performed.

[0003] By the way, as in recent years, the spinning speed is 30
At higher speeds of 00 m / min or more, troubles that were not so much a problem in the past, such as troubles due to the accompanying airflow secondary to the running of the yarn, have increased. Moreover, as the yarn travels at a higher speed, the accompanying airflow increases more and more, so that the influence of the airflow accompanying the yarn traveling at a high speed cannot be ignored.

[0004] Here, a specific example of a known problem caused by an entrained air flow is described in, for example, Japanese Utility Model Publication No. 47-34255, which proposes an attempt to solve a problem related to yarn sway caused by an entrained air flow. I have. In this attempt, in order to reduce the yarn sway in the spinning tube which solidifies the spun yarn, several stages of inverted funnel-shaped caps are stacked at the lower end of the yarn path duct and provided at the center of the spinning tube. An annular chamber is provided outside the cap, and a suction pipe communicates with the annular chamber to rectify the associated airflow of the yarn and control the flow of the associated flow, thereby reducing the yarn sway. .

However, no consideration has been given to the adverse effect of the accompanying airflow in the heating cylinder provided immediately below the spinneret which surrounds the spun yarn group spun from the spinneret. Did not.

[0006]

As a result of close observation of the heating cylinder provided immediately below the spinneret, the present inventor has found that "the flow of the air current accompanying the spun yarn group traveling in the heating cylinder is reduced. (Accompanying airflow), and the static pressure in the heating cylinder is reduced by the influence of the accompanying airflow, whereby cooling air flows into the heating cylinder from the cooling chamber provided on the downstream side. "

As is well known, the heating cylinder provided directly below the spinneret has a great effect on the thinning of the spun yarn group. It is necessary to strictly control the atmosphere temperature in the inside. However, when the cooling air flows into the heating cylinder as described above, the ambient temperature in the heating cylinder changes with time due to the influence of the flowing cooling air. For this reason, it was clarified that adverse effects such as unevenness of fineness were produced between the obtained yarns.

[0008] Accordingly, the problem to be solved by the present invention is to prevent a decrease in static pressure in the heating cylinder caused by an air flow accompanying the traveling yarn group, and thereby a cooling air flow into the heating cylinder. , The atmosphere temperature in the heating cylinder is kept constant so that it does not change with time.
It is an object of the present invention to provide a melt-spinning apparatus capable of spinning a high-quality yarn that does not cause unevenness in fineness between single fibers.

[0009]

According to the present invention, there is provided the following melt-spinning apparatus for solving the above-mentioned problems.

That is, the static pressure in the heating cylinder provided immediately below the spinneret surrounding the spun yarn group spun from the spinneret is substantially equal to the static pressure in the downstream part of the heating cylinder. Or
Or a higher melt spinning device ".

In the apparatus of the present invention, in order to prevent cooling air from flowing in the downstream direction of the heating cylinder, the heating air carried away together with the accompanying airflow is supplemented, thereby reducing the static pressure in the heating cylinder. In order to make the pressure higher than the static pressure downstream of the heating cylinder, it is preferable to provide “heating air supply means for supplying heating air into the heating cylinder”.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic front view partially including a cross section schematically illustrating a melt spinning apparatus of the present invention, and FIG. 2 shows an embodiment of a heating air supply unit for supplying heating air into a heating cylinder. It is the front sectional view illustrated.

Here, in FIG. 1, 1 is a spinneret, 2
Denotes a spun yarn, 3 denotes a heating cylinder, 4 denotes a heating air supply means, 5 denotes an associated air flow, 6 denotes a heating air, 7 denotes a cooling device, and 8 denotes a cooling air. The heating cylinder 3 is provided directly below the spinneret 1 so as to surround the spun yarn group 2 spun from the spinneret 1. The arrows in the figure indicate the flow directions of the accompanying airflow 5, the hot air 6, and the cooling air 8.

In FIG. 2, reference numeral 10 denotes a flow of unheated air supplied to the heated air supply means 4;
Is a heater for heating unheated air, 1
Reference numeral 2 denotes a thermocouple temperature detecting end for detecting the temperature of the heated air.

In the conventional melt spinning apparatus, as shown in FIG. 3, a heated air flow is discharged from the heating cylinder 3 as an accompanying airflow 5 accompanying the traveling yarn group 2, whereby the heating cylinder 3 is heated. Static pressure decreases. For this reason, the cooling air 9 from the cooling device 7 higher than the static pressure in the heating cylinder 3 flows into the heating cylinder 3 and is a major factor that changes the ambient temperature in the heating cylinder. In addition, the inflow of the cooling air 9 into the heating cylinder 3 also causes turbulence in the airflow in the heating cylinder 3, thereby causing the yarn to sway.

[0016] This situation is different from clothing use, in a spinning apparatus having a vertical blown spinning tube for spinning multifilaments for industrial use such as tire cords, in combination with the fact that the upper end of the heating tube is almost airtight. It is a big problem to spin many filaments.

In order to solve the above problem, in the apparatus of the present invention, as shown in FIG. 1, the heating air 6 is supplied into the heating cylinder 3 through the heating air supply means 4, and the heating cylinder 3 is heated. The melt spinning apparatus has a static pressure substantially equal to or higher than the static pressure in the downstream section. Thus, in the device of the present invention,
By replenishing the outflow of the accompanying airflow 5 discharged from the heating cylinder 3 accompanying the traveling spun yarn group 2, the decreasing static pressure is always kept constant. Therefore, in the conventional apparatus to which the heating air 6 is not supplied, the static pressure in the heating cylinder 3 is reduced and the cooling air 8 flows into the heating cylinder 3. Because you can
The predetermined static pressure can be maintained without lowering the static pressure in the heating cylinder 3.

In the apparatus of the present invention, when the heating air 6 is supplied into the heating cylinder 3, it is also important that the supplied heating air does not disturb the ambient temperature in the heating cylinder 3. . Therefore, the heated air 6 is
As shown in (2), the temperature must be maintained substantially the same as the temperature inside the heating cylinder by a heating means such as the heater 11. Therefore, the air 10 which has not yet reached the predetermined temperature
Is heated by a heater 11 and supplied into the heating cylinder 3 while controlling the heated air 6 to a constant temperature by a thermocouple temperature detecting end via a control device (not shown).

It is preferable that the supply of the heated air be uniformly supplied from the entire circumference so as to enclose the spun yarn without being biased to one side. Then, it is preferable that the supplied heated air does not directly hit the spun yarn, thereby preventing the spun yarn from swaying. Needless to say, the amount of the heated air to be supplied is determined according to the accompanying airflow flowing out of the heating cylinder 3 as an accompanying airflow, and this amount depends on spinning conditions such as spinning speed and the number of filaments to be spun. It goes without saying that it is decided.

[0020]

According to the apparatus of the present invention described above,
"By actively supplying heated air into the heating cylinder, it is possible to prevent a decrease in static pressure in the heating cylinder caused by flowing out of the heating cylinder accompanying the traveling yarn group, The cooling air can be prevented from flowing into the heating cylinder, thereby keeping the ambient temperature in the heating cylinder constant so as not to change with time, and as a result, a yarn of excellent quality that does not cause unevenness in fineness between single fibers. It is possible to provide a melt spinning apparatus capable of spinning a strip. "

[Brief description of the drawings]

FIG. 1 is a schematic front view schematically showing a melt spinning apparatus according to the present invention, including a part of a cross section.

FIG. 2 is a front cross-sectional view illustrating an embodiment of a heating air supply unit that supplies heating air into a heating cylinder.

FIG. 3 is a schematic front view schematically illustrating a conventional melt spinning apparatus, partially including a cross section.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Spinneret 2 Spun yarn 3 Heating cylinder 4 Heating air supply means 5 Associated air flow 6 Heating air 7 Cooling device 8 Cooling air

Claims (2)

[Claims] 1. A static pressure in a heating cylinder provided immediately below a spinneret surrounding a group of spun yarns spun from a spinneret is substantially equal to a static pressure in a downstream portion of the heating cylinder. Or a higher melt spinning device. 2. The melt spinning apparatus according to claim 1, further comprising heating air supply means for supplying heating air into the heating cylinder.