U.S. patent application number 10/516835 was filed with the patent office on 2006-07-06 for device and method for manufacturing thread line.
Invention is credited to Takashi Fujii, Hiroki Furuta, Masahito Hisada, Takao Sano.
Application Number | 20060145385 10/516835 |
Document ID | / |
Family ID | 29714323 |
Filed Date | 2006-07-06 |
United States Patent
Application |
20060145385 |
Kind Code |
A1 |
Fujii; Takashi ; et
al. |
July 6, 2006 |
Device and method for manufacturing thread line
Abstract
Production of a yarn, using a spinneret having numerous spinning
holes arranged in a straight line(s), and a spinning tube installed
below it, spaced from it, and having a filament passage rectangular
in cross section with its long side direction agreeing with the
direction in which the spinning holes are arranged side by side,
wherein gas is injected from the injection holes formed on both the
long sides of the filament passage for injecting gas obliquely
downward to the filaments, for disposing the numerous filaments in
a row and for forming a gas stream flowing downward in the filament
passage, characterized in that the speed of the gas stream flowing
downward in the filament passage is not less than 60% of the
take-up speed of the numerous filaments, or that the gas generated
from the numerous filaments is sucked and discharged outside, in
the range between the spinneret and the spinning tube. Even if the
yarn runs at a high speed, the obtained yarn can have a high
elongation.
Inventors: |
Fujii; Takashi; (Kyoto-shi,
JP) ; Sano; Takao; (Moriyama-shi, JP) ;
Furuta; Hiroki; (Kyoto-shi, JP) ; Hisada;
Masahito; (Otsu-shi, JP) |
Correspondence
Address: |
RATNERPRESTIA
P O BOX 980
VALLEY FORGE
PA
19482-0980
US
|
Family ID: |
29714323 |
Appl. No.: |
10/516835 |
Filed: |
May 28, 2003 |
PCT Filed: |
May 28, 2003 |
PCT NO: |
PCT/JP03/06653 |
371 Date: |
December 2, 2004 |
Current U.S.
Class: |
264/130 ;
264/211.12; 264/211.14; 264/555; 425/72.2 |
Current CPC
Class: |
D01D 5/092 20130101;
D01D 5/0985 20130101 |
Class at
Publication: |
264/130 ;
264/211.14; 264/211.12; 264/555; 425/072.2 |
International
Class: |
D01D 5/092 20060101
D01D005/092; D01D 5/096 20060101 D01D005/096 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 3, 2002 |
JP |
2002-161124 |
Mar 18, 2003 |
JP |
2003-73260 |
Claims
1. A method for producing a yarn consisting of numerous filaments,
using: (a) a spinneret having numerous spinning holes to discharge
a flowable polymer continuously for forming filaments, (b) a
spinning tube having a filament passage through which the numerous
filaments formed by said numerous spinning holes run downward from
said spinneret, and installed below and spaced from said spinneret,
(c) an oiling means for applying an oil to the numerous filaments
coming out of said spinning tube, (d) a filament take-up means for
taking up the numerous filaments coming from said oiling means, and
(e) a winding means for winding the numerous filaments coming from
said filament take-up means, characterized in that (f) gas
injection holes are provided, which inject gas obliquely downward
from outside the numerous filaments entering the filament passage
of said spinning tube, toward the numerous filaments, while the
numerous filaments are still flowable, to ensure that the numerous
filaments can be disposed along one straight line or one circle
without overlapping each other, and further to ensure that,
subsequently after disposing the numerous filaments, the injected
gas can form a gas stream flowing downward together with the
numerous filaments in the filament passage of said spinning tube,
and (g) the velocity of the gas stream flowing downward together
with the numerous filaments in the filament passage of said
spinning tube is not less than 60% of a take-up speed of the
numerous filaments taken up by said filament take-up means.
2. A method for producing a yarn, according to claim 1, wherein
said numerous filaments are disposed along one straight line; the
cross sectional form of the filament passage of said spinning tube
is rectangular; the direction of the long sides of said rectangle
agrees with the direction of said straight line; and the following
relation is satisfied d.times.3.ltoreq.Ex.ltoreq.d.times.20 where
Ex is the length of the short sides of said rectangle, and d is the
diameter of said spinning holes.
3. A method for producing a yarn, according to claim 2, wherein
said numerous spinning holes are arranged in straight lines; and
the number of the straight lines is 3 or less.
4. A method for producing a yarn, according to claim 1, wherein the
following relation is satisfied: La.ltoreq.Lg/2 where Lg is the
distance between said spinneret and the position at which said
numerous filaments are solidified to lose their flowability and
reach the take-up speed of the numerous filaments taken up by said
filament take-up means, and La is the distance between said
spinneret and the position at which the acceleration of said
numerous filaments becomes largest.
5. A method for producing a yarn, according to claim 4, wherein the
velocity of the gas stream flowing downward together with said
numerous filaments in the filament passage of said spinning tube is
higher than the running speed of said numerous filaments in the
range of the distance Lg between said spinneret and the position at
which the running speed of said numerous filaments reaches the
take-up speed of the numerous filaments taken up by said filament
take-up means.
6. A method for producing a yarn, according to claim 1, wherein a
gas suction and discharge means for sucking and discharging gas
existing around the numerous filaments running from said spinning
holes toward said filament passage is installed between said
spinneret and said spinning tube, to ensure that the gas existing
around said numerous filaments can be sucked and discharged.
7. A method for producing a yarn, according to claim 6, wherein the
numerous filaments are disposed along one straight line; the cross
sectional form of the filament passage of said spinning tube is
rectangular; the direction of the long sides of said rectangle
agrees with the direction of said straight line; and the following
relation is satisfied Ex.ltoreq.10 mm where Ex is the length of the
short sides of said rectangle.
8. A method for producing a yarn consisting of numerous filaments,
using: (a) a spinneret having numerous spinning holes formed to
discharge a flowable polymer continuously for forming filaments,
(b) a spinning tube having a filament passage through which the
numerous filaments formed by said numerous spinning holes run
downward from said spinneret, and installed below and spaced from
said spinneret, (c) an oiling means for applying an oil to the
numerous filaments coming out of said spinning tube, (d) a filament
take-up means for taking up the numerous filaments coming from said
oiling means, and (e) a winding means for winding the numerous
filaments coming from said filament take-up means, characterized in
that (f) gas injection holes are provided, which inject gas
obliquely downward from outside the numerous filaments entering the
filament passage of said spinning tube, toward the numerous
filaments, while the numerous filaments are still flowable, to
ensure that the numerous filaments can be disposed along one
straight line or one circle without overlapping each other, and
further to ensure that, subsequently after disposing the numerous
filaments, the injected gas can form a gas stream flowing downward
together with the numerous filaments in the filament passage of
said spinning tube, and (g) the following relation is satisfied:
La.ltoreq.Lg/2 where Lg is the distance between said spinneret and
the position at which said numerous filaments are solidified to
lose their flowability and reach the take-up speed of the numerous
filaments taken up by said filament take-up means, and La is the
distance between said spinneret and the position at which the
acceleration of said numerous filaments becomes largest.
9. A method for producing a yarn, according to claim 8, wherein the
velocity of the gas stream flowing downward together with said
numerous filaments in said filament passage is higher than the
running speed of said numerous filaments.
10. A method for producing a yarn consisting of numerous filaments,
using: (a) a spinneret having numerous spinning holes formed to
discharge a flowable polymer continuously for forming filaments,
(b) a spinning tube having a filament passage through which the
numerous filaments formed by said numerous spinning holes run
downward from said spinneret, and installed below and spaced from
said spinneret, (c) an oiling means for applying an oil to the
numerous filaments coming out of said spinning tube, (d) a filament
take-up means for taking up the numerous filaments coming from said
oiling means, and (e) a winding means for winding the numerous
filaments coming from said filament take-up means, characterized in
that (f) gas injection holes are provided, which inject gas
obliquely downward from outside the numerous filaments entering the
filament passage of said spinning tube, toward the numerous
filaments, while the numerous filaments are still flowable, to
ensure that the numerous filaments can be disposed along one
straight line or one circle without overlapping each other, and
further to ensure that, subsequently after disposing the numerous
filaments, the injected gas can form a gas stream flowing downward
together with the numerous filaments in the filament passage of
said spinning tube, and (g) a gas suction device is provided
between said spinneret and said spinning tube, to suck the gas
existing around said numerous filaments and to discharge the gas
outside.
11. A method for producing a yarn, according to claim 10, wherein
the width of said filament passage in the direction perpendicular
to the direction in which said numerous filaments are disposed side
by side is 10 mm or less.
12. A method for producing a yarn, according to claim 10, wherein
the suction of the gas existing around said numerous filaments is
carried out on both sides of the disposal of said numerous
filaments.
13. A method for producing a yarn, according to claim 10, wherein
said numerous spinning holes are arranged in straight lines; and
the number of the straight lines is 3 or less.
14. A method for producing a yarn, according to claim 10, wherein
outside air suction spaces are formed between said gas suction
device and said spinning tube, to ensure that the sucked outside
air flows into said filament passage.
15. An apparatus for producing a yarn consisting of numerous
filaments, having: (a) a spinneret having numerous spinning holes
formed to discharge a flowable polymer continuously for forming
filaments, (b) a spinning tube having a filament passage through
which the numerous filaments formed by said numerous spinning holes
run downward from said spinneret, and installed below and spaced
from said spinneret, (c) an oiling means for applying an oil to the
numerous filaments coming out of said spinning tube, (d) a filament
take-up means for taking up the numerous filaments coming from said
oiling means, and (e) a winding means for winding the numerous
filaments coming from said filament take-up means, characterized in
that (f) gas injection holes are provided, which inject gas
obliquely downward from outside the numerous filaments entering the
filament passage of said spinning tube, toward the numerous
filaments, while the numerous filaments are still flowable, to
ensure that the numerous filaments can be disposed along one
straight line or one circle without overlapping each other, and
further to ensure that, subsequently after disposing the numerous
filaments, the injected gas can form a gas stream flowing downward
together with the numerous filaments in the filament passage of
said spinning tube, and (g) a means is provided for adjusting the
injection conditions of the gas injected from said gas injection
holes or adjusting the take-up speed of the numerous filaments
taken up by said filament take-up means, to ensure that the
velocity of the gas stream flowing downward together with the
numerous filaments in the filament passage of said spinning tube is
not less than 60% of the take-up speed of the numerous filaments
taken up by said filament take-up means.
16. An apparatus for producing a yarn, according to claim 15,
wherein said numerous filaments are disposed along one straight
line; the cross sectional form of the filament passage of said
spinning tube is rectangular; the direction of the long sides of
said rectangle agrees with the direction of said straight line; and
the following relation is satisfied:
d.times.3.ltoreq.Ex.ltoreq.d.times.20 where Ex is the length of the
short sides of said rectangle, and d is the diameter of said
spinning holes.
17. An apparatus for producing a yarn, according to claim 16,
wherein said numerous spinning holes are arranged in straight
lines; and the number of the straight lines is 3 or less.
18. An apparatus for producing a yarn, according to claim 15,
wherein the following relation is satisfied: La.ltoreq.Lg/2 where
Lg is the-distance between said spinneret and the position at which
said numerous filaments are solidified to lose their flowability
and reach the take-up speed of the numerous filaments taken up by
said filament take-up means, and La is the distance between said
spinneret and the position at which the acceleration of said
numerous filaments becomes largest.
19. An apparatus for producing a yarn, according to claim 18,
wherein the velocity of the gas stream flowing downward together
with said numerous filaments in the filament passage of said
spinning tube is higher than the running speed of said numerous
filaments, in the range of the distance Lg between said spinneret
and the position at which the running speed of the numerous
filaments reaches the take-up speed of the numerous filaments taken
up by said filament take-up means.
20. An apparatus for producing a yarn, according to claim 15,
wherein a gas suction and discharge means for sucking and
discharging the gas existing around the numerous filaments running
from said spinning holes toward said filament passage is installed
between said spinneret and said spinning tube, to ensure that the
gas existing around said numerous filaments can be sucked and
discharged.
21. An apparatus for producing a yarn, according to claim 20,
wherein the numerous filaments are disposed along one straight
line; the cross sectional form of the filament passage of said
spinning tube is rectangular; the direction of the long sides of
said rectangle agrees with the direction of said straight line; and
the following relation is satisfied: Ex.ltoreq.10 mm where Ex is
the length of the short sides of said rectangle.
22. An apparatus for producing a yarn consisting of numerous
filaments, having: (a) a spinneret having numerous spinning holes
formed to discharge a flowable polymer continuously for forming
filaments, (b) a spinning tube having a filament passage through
which the numerous filaments formed by said numerous spinning holes
run downward from said spinneret, and installed below and spaced
from said spinneret, (c) an oiling means for applying an oil to the
numerous filaments coming out of said spinning tube, (d) a filament
take-up means for taking up the numerous filaments coming from said
oiling means, and (e) a winding means for winding the numerous
filaments coming from said filament take-up means, characterized in
that (f) gas injection holes are provided, which inject gas
obliquely downward from outside the numerous filaments entering the
filament passage of said spinning tube, toward the numerous
filaments, while the numerous filaments are still flowable, to
ensure that the numerous filaments can be disposed along one
straight line or one circle without overlapping each other, and
further to ensure that, subsequently after disposing the numerous
filaments, the injected gas can form a gas stream flowing downward
together with the numerous filaments in the filament passage of
said spinning tube, and (g) the following relation is satisfied:
La.ltoreq.Lg/2 where Lg is the distance between said spinneret and
the position at which said numerous filaments are solidified to
lose their flowability and reach the take-up speed of the numerous
filaments taken up by said filament take-up means, and La is the
distance between said spinneret and the position at which the
acceleration of said numerous filaments becomes largest.
23. An apparatus for producing a yarn, according to claim 22,
wherein the velocity of the gas stream flowing downward together
with said numerous filaments in said filament passage is higher
than the running speed of said numerous filaments.
24. An apparatus for producing a yarn consisting of numerous
filaments, having: (a) a spinneret having numerous spinning holes
formed to discharge a flowable polymer continuously for forming
filaments, (b) a spinning tube having a filament passage through
which the numerous filaments formed by said numerous spinning holes
run downward from said spinneret, and installed below and spaced
from said spinneret, (c) an oiling means for applying an oil to the
numerous filaments coming out of said spinning tube, (d) a filament
take-up means for taking up the numerous filaments coming from said
oiling means, and (e) a winding means for winding the numerous
filaments coming from said filament take-up means, characterized in
that (f) gas injection holes are provided, which inject gas
obliquely downward from outside the numerous filaments entering the
filament passage of said spinning tube, toward the numerous
filaments, while the numerous filaments are still flowable, to
ensure that the numerous filaments can be disposed along one
straight line or one circle without overlapping each other, and
further to ensure that, subsequently after disposing the numerous
filaments, the injected gas can form a gas stream flowing downward
together with the numerous filaments in the filament passage of
said spinning tube, and (g) a gas suction device is installed
between said spinneret and said spinning tube, to suck the gas
existing around said numerous filaments and to discharge the gas
outside.
25. An apparatus for producing a yarn, according to claim 24,
wherein the width of said filament passage in the direction
perpendicular to the direction in which said numerous filaments are
disposed side by side is 10 mm or less.
26. An apparatus for producing a yarn, according to claim 24,
wherein the suction of the gas existing around said numerous
filaments is carried out on both sides of the disposal of said
numerous filaments.
27. An apparatus for producing a yarn, according to claim 24,
wherein said numerous spinning holes are arranged in straight
lines; and the number of the straight lines is 3 or less.
28. An apparatus for producing a yarn, according to claim 24,
wherein outside air suction spaces are formed between said gas
suction device and said spinning tube, to ensure that the sucked
outside air flows into said filament passage.
Description
TECHNICAL FIELD
[0001] The present invention relates to a method and apparatus for
producing a yarn consisting of numerous filaments, comprising the
steps of discharging a flowable polymer from numerous spinning
holes formed in a spinneret, to form the numerous filaments,
letting the formed numerous filaments pass through a filament
passage satisfying specific gas stream conditions of a spinning
tube installed below the spinneret, taking up the numerous
filaments coming out of the filament passage, and winding the
numerous filaments.
[0002] A typical example of the polymer used in the yarn production
method is a polyester polymer (e.g., polyethylene terephthalate).
Furthermore, the yarn production method can also be preferably used
for producing a partially oriented yarn.
BACKGROUND ART
[0003] For producing a yarn, especially a partially oriented yarn
(POY) of a polyester or the like, generally an apparatus shown in
FIG. 1 is used. In FIG. 1, a spinneret 1 has numerous spinning
holes 6. Numerous filaments F discharged from the spinning holes 6
are cooled and solidified by means of cooling air 3a supplied by a
cooling means 3. The solidified numerous filaments F are taken up
by a godet roller 4, to form a yarn Y. The yarn Y consisting of the
numerous filaments F is wound around a bobbin by a winder 5, to
produce a yarn package.
[0004] To enhance yarn production efficiency, it is generally
attempted to raise a yarn production speed. In the case where the
apparatus shown in FIG. 1 is used, if the yarn take-up speed of a
godet roller 4 is raised, the take-up tension T acting on the
filaments F upstream of the godet roller 4 increases. As a result,
the elongation of the produced yarn Y declines. That is, for
example, if a yarn of polyethylene terephthalate is produced at a
take-up speed of 3,000 m/min, the elongation of the produced yarn
becomes 135%. If the take-up speed is increased to 4,000 m/min, the
elongation of the yarn becomes 90%, and if the take-up speed is
increased to 5,000 m/min, the elongation of the yarn becomes 65%.
At a higher take-up speed, the elongation of the produced yarn
becomes lower.
[0005] Furthermore, in the apparatus shown in FIG. 1, a circular
spinneret 1 shown in FIG. 2 is used. The spinneret 1 has numerous
spinning holes 6. The polymer discharged from the numerous spinning
holes 6 forms numerous filaments F. The numerous filaments F run
downward. To the running numerous filaments F, cooling air 3a is
supplied from one side only. Especially when the take-up speed is
high, the volume of the cooling air 3a is also increased.
Therefore, the filaments F swing very greatly. Furthermore, since
the distances of the respective numerous filaments F from a cooling
means 3 are different, the respective filaments F are cooled in
different conditions. The yarn Y consisting of the numerous
filaments F produced in this way has filament irregularity.
[0006] As described above, it is difficult to produce a yarn at a
higher take-up speed for achieving a higher production efficiency
with the yarn elongation kept at the same level as achieved at a
low take-up speed without causing any difference among the
filaments constituting the yarn (without causing filament
irregularity).
[0007] An attempt to overcome the difficulty for obtaining a high
elongation yarn at a high speed is described in U.S. Pat. No.
5,824,248. The outline of the attempt is shown in FIG. 3. The
spinning apparatus shown in FIG. 3 has a cylindrical cooling means
55 and a tube 73 having a diameter smaller than that of the
cylindrical cooling means 55 below a spinneret 1. Cooling air 55a
of the cylindrical cooling means 55 generates a descending air
stream in the tube 73 positioned downstream of it. It is proposed
to impart an air stream in the tube 73 to the numerous filaments F
discharged from the numerous spinning holes 6 of the spinneret
1.
[0008] JP-A-08-506393 proposes to adjust a flow velocity of an air
stream flowing in a tube to a velocity equal to a running speed of
the polymer, for decreasing a take-up tension T acting on the
filaments. It is described that this constitution allows a yarn to
be produced stably even if a take-up speed of the yarn is kept
high.
[0009] However, in these methods, like the apparatus shown in FIG.
1, a polymer is discharged from the numerous spinning holes 6
formed in the circular spinneret 1 shown in FIG. 2, to form
numerous filaments F. Therefore, the distances of the respective
numerous filaments F from the cylindrical cooling means 55 are
different. Furthermore, due to the difference in diameter between
the cylindrical cooling means 55 and the tube 73, the cooling air
55a becomes different in its state between the outside and the
inside of the numerous filaments. Therefore, the outside running
filaments F are different in cooling state from the inside running
filaments F. The yarn Y consisting of the numerous filaments F
produced in this way has filament irregularity.
[0010] JP-A-2001-262427 proposes to inject a heating fluid from
heating fluid injection holes formed around the spinning holes of
the spinneret obliquely downward to the running filaments. It is
intended that the filaments discharged from the spinning holes are
kept at a high temperature and made thinner by means of the heating
fluid flow. It is described that with this constitution, even if
the spinning speed is raised, that is, even if the filament take-up
speed is raised, a high elongation yarn can be obtained.
Furthermore, it is described that if a suction means is installed
downstream of the heating fluid injection holes, the discharged
filaments can be made thinner more positively.
[0011] However, in this spinning apparatus, the heating fluid
injected from the heating fluid injection holes flows toward the
suction means. So, there is a problem that the heating medium heats
the suction means. Furthermore, there is another problem that the
heating fluid introduced into the suction means destabilizes
temperature of a gas stream running in the suction means. The
unstable temperature condition affects the filaments running in the
suction means. The yarn produced after undergoing this condition
has filament irregularity.
[0012] Moreover, since the heating fluid injection holes are formed
directly in the spinneret, the injected heating fluid does not have
an established passage on the discharge face of the spinning holes
of the spinneret, and is merely released into the space between the
spinneret and the suction means. For this reason, between the
central portion and the end portions of the numerous spinning holes
arranged along straight lines, a problem arises that force of the
heating fluid acting on the filaments becomes different. The yarn
consisting of numerous filaments produced like this has filament
irregularity.
[0013] On the other hand, it can happen that a gas is generated
from the polymer flow as just discharged from the spinning holes of
the spinneret. The gas contains low polymerization products of the
intended polymer, i.e., the monomer, oligomer (hereinafter called a
volatile substance), etc. The volatile substance is deposited on
the spinneret face and its vicinity. The deposit causes the
filaments to be broken during spinning. If a filament is broken,
the spinning work must be suspended to correct the trouble,
disturbing the continuous operation of spinning process. Such a gas
is generated not only in the case where polyethylene terephthalate
is spun, but also in the case where another polymer is spun.
Especially, thermally decomposable polymers such as polyamides,
polypropylene and aliphatic polyesters (polylactic acid, etc.)
generate the gas in a large amount. The deposition of the volatile
substance caused by the generated gas disturbs the continuous
operation of spinning process.
[0014] JP-B-50-13924 and JP-A-9-250022 respectively disclose a
device for sucking a gas generated below the spinneret. The device
sucks the gas from lateral sides of the polymer flow (filaments F)
as just discharged the spinning holes of the spinneret.
[0015] However, according to the suction method, in the case where
the filaments F are discharged from the numerous spinning holes
substantially uniformly distributed in the circular spinneret shown
in FIG. 2, only the gas existing near the filaments F positioned
outside can be sufficiently sucked. Therefore, the gas existing
near the filaments positioned inside cannot be sufficiently
removed. There occurs a state where the running filaments F entrain
the gas, to carry it in the running direction of the filaments
F.
[0016] Also in the spinning process disclosed in U.S. Pat. No.
5,824,248 mentioned above, the gas is generated below the
spinneret. However, in this case, since the cylindrical cooling
means 55 keeps the area below the spinneret 1 gas-tight, the
cooling air 55a supplied from it carries the gas containing the
volatile substance toward the tube 73 positioned downstream and is
discharged from the bottom end of the tube 73. Therefore, no gas
remains near the spinneret face, and the adhesion of the deposit to
the spinneret face caused by the gas is hard to occur. So, in such
a spinning apparatus, it is not necessary to install the suction
means as described in JP-B-50-13924 or JP-A-09-250022 mentioned
above for decreasing the contamination of the spinneret face.
[0017] On the other hand, U.S. Pat. No. 5,824,248 mentioned above
proposes that the inner diameter of the tube should be 25 mm or
more. Therefore, in this spinning apparatus, since a tube having a
large inner diameter is used, even if the volatile substance in the
passing gas is deposited on the inner wall of the tube, it does not
affect the filaments running in the tube.
[0018] The object of the invention is to overcome the
above-mentioned problems of the prior art, by providing a method
and apparatus for producing a yarn free from irregularity and
having a high elongation even if the speed for taking up the
numerous filaments is raised.
DISCLOSURE OF THE INVENTION
[0019] The present invention provides a method for producing a yarn
consisting of numerous filaments, using:
[0020] (a) a spinneret having numerous spinning holes to discharge
a flowable polymer continuously for forming filaments,
[0021] (b) a spinning tube having a filament passage through which
the numerous filaments formed by the numerous spinning holes run
downward from the spinneret, and installed below and spaced from
the spinneret,
[0022] (c) an oiling means for applying an oil to the numerous
filaments coming out of the spinning tube,
[0023] (d) a filament take-up means for taking up the numerous
filaments coming from the oiling means, and
[0024] (e) a winding means for winding the numerous filaments
coming from the filament take-up means, characterized in that
[0025] (f) gas injection holes are provided, which inject gas
obliquely downward from outside the numerous filaments entering the
filament passage of the spinning tube, toward the numerous
filaments, while the numerous filaments are still flowable, to
ensure that the numerous filaments can be disposed along one
straight line or one circle without overlapping each other, and
further to ensure that, subsequently after disposing the numerous
filaments, the injected gas can form a gas stream flowing downward
together with the numerous filaments in the filament passage of the
spinning tube, and
[0026] (g) the velocity of the gas stream flowing downward together
with the numerous filaments in the filament passage of the spinning
tube is not less than 60% of the take-up speed of the numerous
filaments taken up by the filament take-up means.
[0027] In the yarn production method of the invention, either of
the following requirements (g) can be employed instead of the
above-mentioned requirement (g).
[0028] A method for producing a yarn, wherein
[0029] (g) the following relation is satisfied: La.ltoreq.Lg/2
where Lg is the distance between the spinneret and the position at
which the numerous filaments are solidified to lose their
flowability and reach the take-up speed of the numerous filaments
taken up by the filament take-up means, and La is the distance
between the spinneret and the position at which the acceleration of
the numerous filaments becomes largest.
[0030] A method for producing a yarn, wherein
[0031] (g) a gas suction device is installed between the spinneret
and the spinning tube, to suck the gas existing around the numerous
filaments and to discharge the gas outside.
[0032] In the yarn production method of the invention, it is
preferred that the numerous filaments are disposed along one
straight line, that the cross sectional form of the filament
passage of the spinning tube is rectangular, that the direction of
the long sides of the rectangle agrees with the direction of the
straight line, and that the following relation is satisfied:
d.times.3.ltoreq.Ex.ltoreq.d.times.20 where Ex is the length of the
short sides of the rectangle, and d is the diameter of the spinning
holes.
[0033] In the yarn production method of the invention, it is
preferred that the numerous spinning holes are arranged in straight
lines, and that the number of the straight lines is 3 or less.
[0034] In the yarn production method of the invention, it is
preferred that the following relation is satisfied: La.ltoreq.Lg/2
where Lg is the distance between the spinneret and the position at
which the numerous filaments are solidified to lose their
flowability and reach the take-up speed of the numerous filaments
taken up by the filament take-up means, and La is the distance
between the spinneret and the position at which the acceleration of
the numerous filaments becomes largest.
[0035] In the yarn production method of the invention, it is
preferred that a velocity of the gas stream flowing downward
together with the numerous filaments in the filament passage of the
spinning tube is higher than the running speed of the numerous
filaments in the range of the distance Lg between the spinneret and
the position at which the running speed of the numerous filaments
reaches the take-up speed of the numerous filaments taken up by the
filament take-up means.
[0036] In the yarn production method of the invention, it is
preferred that a gas suction and discharge means for sucking and
discharging gas existing around the numerous filaments running from
the spinning holes toward the filament passage is installed between
the spinneret and the spinning tube, to ensure that the gas
existing around the numerous filaments can be sucked and
discharged.
[0037] In the yarn production method of the invention, it is
preferred that the numerous filaments are disposed along one
straight line, that the cross sectional form of the filament
passage of the spinning tube is rectangular, that the direction of
the long sides of the rectangle agrees with the direction of the
straight line, and that the following relation is satisfied
Ex.ltoreq.10 mm where Ex is the length of the short sides of the
rectangle.
[0038] The apparatus for producing a yarn of the invention is as
follows.
[0039] An apparatus for producing a yarn consisting of numerous
filaments, having:
[0040] (a) a spinneret having numerous spinning holes formed to
discharge a flowable polymer continuously for forming
filaments,
[0041] (b) a spinning tube having a filament passage through which
the numerous filaments formed by the numerous spinning holes run
downward from the spinneret, and installed below and spaced from
the spinneret,
[0042] (c) an oiling means for applying an oil to the numerous
filaments coming out of the spinning tube,
[0043] (d) a filament take-up means for taking up the numerous
filaments coming from the oiling means, and
[0044] (e) a winding means for winding the numerous filaments
coming from the filament take-up means, characterized in that
[0045] (f) gas injection holes are provided, which inject gas
obliquely downward from outside the numerous filaments entering the
filament passage of the spinning tube, toward the numerous
filaments, while the numerous filaments are still flowable, to
ensure that the numerous filaments can be disposed along one
straight line or one circle without overlapping each other, and
further to ensure that, subsequently after disposing the numerous
filaments, the injected gas can form an air stream flowing downward
together with the numerous filaments in the filament passage of the
spinning tube, and
[0046] (g) a means is provided for adjusting the injection
conditions of the gas injected from the gas injection holes or
adjusting the take-up speed of the numerous filaments taken up by
the filament take-up means, to ensure that the velocity of the gas
stream flowing downward together with the numerous filaments in the
filament passage of the spinning tube is not less than 60% of the
take-up speed of the numerous filaments taken up by the filament
take-up means.
[0047] In the yarn production apparatus of the invention, either of
the following requirements (g) can be employed instead of the
above-mentioned requirement (g).
[0048] An apparatus for producing a yarn, wherein
[0049] (g) the following relation is satisfied: La.ltoreq.Lg/2
where Lg is the distance between the spinneret and the position at
which the numerous filaments are solidified to lose their
flowability and reach the take-up speed of the numerous filaments
taken up by the filament take-up means, and La is the distance
between the spinneret and the position at which the acceleration of
the numerous filaments becomes largest.
[0050] An apparatus for producing a yarn, wherein
[0051] (g) a gas suction device is installed between the spinneret
and the spinning tube, to suck the gas existing around the numerous
filaments and to discharge the gas outside.
[0052] In the yarn production apparatus of the invention, it is
preferred that the numerous filaments are disposed along one
straight line, that the cross sectional form of the filament
passage of the spinning tube is rectangular, that the direction of
the long sides of the rectangle agrees with the direction of the
straight line, and that the following relation is satisfied:
d.times.3.ltoreq.Ex.ltoreq.d.times.20 where Ex is the length of the
short sides of the rectangle, and d is the diameter of the spinning
holes.
[0053] In the yarn production apparatus of the invention, it is
preferred that the numerous spinning holes are arranged in straight
lines, and that the number of the straight lines is 3 or less.
[0054] In the yarn production apparatus of the invention, it is
preferred that the following relation is satisfied: La<Lg/2
where Lg is the distance between the spinneret and the position at
which the numerous filaments are solidified to lose their
flowability and reach the take-up speed of the numerous filaments
taken up by the filament take-up means, and La is the distance
between the spinneret and the position at which the acceleration of
the numerous filaments becomes largest.
[0055] In the yarn production apparatus of the invention, it is
preferred that the velocity of the gas stream flowing downward
together with the numerous filaments in the filament passage of the
spinning tube is higher than the running speed of the numerous
filaments in the range of the distance Lg between the spinneret and
the position at which the running speed of the numerous filaments
reaches the take-up speed of the numerous filaments taken up by the
filament take-up means.
[0056] In the yarn production apparatus of the invention, it is
preferred that a gas suction and discharge means for sucking and
discharging gas existing around the numerous filaments running from
the spinning holes toward the filament passage is installed between
the spinneret and the spinning tube, to ensure that the gas
existing around the numerous filaments can be sucked and
discharged.
[0057] In the yarn production apparatus of the invention, it is
preferred that the numerous filaments are disposed along one
straight line, that the cross sectional form of the filament
passage of the spinning tube is rectangular, that the direction of
the long sides of the rectangle agrees with the direction of the
straight line, and that the following relation is satisfied:
Ex.ltoreq.10 mm where Ex is the length of the short sides of the
rectangle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0058] FIG. 1 is a schematic typical view showing a conventional
yarn production apparatus.
[0059] FIG. 2 is a schematic typical view showing the bottom face
of the spinneret used in the apparatus of FIG. 1.
[0060] FIG. 3 is a schematic typical view showing another
conventional yarn production apparatus than the apparatus of FIG.
1.
[0061] FIG. 4 is a schematic typical view showing an embodiment of
the yarn production apparatus of the invention.
[0062] FIGS. 5A, 5B and 5D are schematic typical views showing the
bottom faces of three typical examples of the spinneret used in the
apparatus of FIG. 4. FIG. 5C is a projected typical front view
showing the spinneret of FIG. 5B. FIG. 5E is a projected typical
front view of the spinneret of FIG. 5D.
[0063] FIG. 6 is a schematic vertical sectional view showing the
spinning tube used in the apparatus of FIG. 4.
[0064] FIG. 7 is a schematic X-X cross-sectional view showing the
spinning tube of FIG. 6.
[0065] FIG. 8 is a schematic perspective view showing a partial
upper portion of the spinning tube of FIG. 4.
[0066] FIG. 9 is a schematic vertical sectional view showing
another mode of the spinning tube of FIG. 4.
[0067] FIG. 10 is a schematic vertical sectional view showing a
lower portion of a further other mode of the spinning tube of FIG.
4.
[0068] FIG. 11 is a partial schematic vertical sectional view
showing a mode in which a discharge-destined flow suction means is
provided below the spinning tube in the apparatus of FIG. 4.
[0069] FIG. 12 is a partial schematic vertical sectional view
showing a mode in which flow regulation sections are installed
above the spinning tube in the apparatus of FIG. 4.
[0070] FIG. 13 is a perspective view showing an example of the
grate members installed in the flow regulation sections of FIG.
12.
[0071] FIG. 14 is a partial schematic perspective view showing a
mode in which an air stream regulation means is installed above the
spinning tube in the apparatus of FIG. 4.
[0072] FIG. 15 is a schematic perspective view showing a
temperature regulation means installed above the spinning tube in
the apparatus of FIG. 4.
[0073] FIG. 16 is a schematic perspective view showing another mode
of the temperature regulation means of FIG. 15.
[0074] FIG. 17 is a partial schematic vertical sectional view
showing a mode in which a compressed air circulation passage is
added to the spinning tube in the apparatus of FIG. 4.
[0075] FIG. 18 is a schematic typical view showing another
embodiment of the yarn production apparatus of the invention.
[0076] FIG. 19 is a schematic vertical sectional view showing a
mode of the gas suction device used in the apparatus of FIG.
18.
[0077] FIG. 20 is a schematic vertical sectional view showing
another mode of the gas suction device used in the apparatus of
FIG. 18.
[0078] FIG. 21 is a schematic vertical sectional view showing a
further other mode of the gas suction device used in the apparatus
of FIG. 18.
[0079] FIG. 22 is a schematic cross sectional view showing the gas
suction device used in the apparatus of FIG. 18.
[0080] FIG. 23 is a schematic typical view showing a further other
embodiment of the yarn production apparatus of the invention.
[0081] FIG. 24 is a schematic perspective view showing a mode of
the grate members of the flow regulation sections of FIG. 23.
[0082] FIG. 25 is a schematic perspective view showing the flow
regulation sections of FIG. 23.
[0083] FIG. 26 is a schematic typical view showing a further other
embodiment of the yarn production apparatus of the invention.
[0084] FIG. 27 is a graph showing how the speed of the filaments
composed of a polymer discharged from the spinneret changes in
relation with the distance from the spinneret in the apparatus of
FIG. 4.
[0085] FIG. 28 is a schematic perspective view showing the spinning
tube and the oiling means installed in the apparatus of FIG. 4.
[0086] FIG. 29 is a schematic perspective typical view showing a
further other embodiment of the yarn production apparatus of the
invention.
[0087] FIG. 30 is a partial schematic perspective typical view
showing a further other embodiment of the yarn production apparatus
of the invention.
[0088] FIG. 31 is a partial schematic perspective typical view
showing a further other embodiment of the yarn production apparatus
of the invention.
[0089] FIG. 32 is a schematic typical view for illustrating the
method of measuring the running speed of filaments.
[0090] FIG. 33 is a graph showing how the speed of the filaments
composed of a polymer discharged from the spinneret changed in
relation with the distance from the spinneret in Examples 1 through
4.
[0091] FIG. 34 is a graph showing how the speed of the filaments
composed of a polymer discharged from the spinneret changed in
relation with the distance from the spinneret in Comparative
Examples 1 through 3.
[0092] FIG. 35 is a graph showing how the speed of the filaments
composed of a polymer discharged from the spinneret changed in
relation with the distance from the spinneret in Examples 1 and 5
and Comparative Example 4.
THE BEST MODES FOR CARRYING OUT THE INVENTION
[0093] Embodiments of the invention are described below further in
reference to drawings.
[0094] In the following embodiments, the method and apparatus for
producing a polyester yarn, especially a partially oriented yarn
(POY) are described.
[0095] In FIG. 4, a yarn production apparatus 10 of the invention
has a spinneret 12 engaged with a spinning block 11 in a
melt-spinning machine (not illustrated) and having numerous
spinning holes 13 formed for continuously discharging a flowable
polymer for forming filaments. Below the spinneret 12 and being
spaced from the spinneret 12, a spinning tube (ejector) (air
applying means) 20 is installed. The spinning tube 20 has a
filament passage 25 (FIG. 6) through which the numerous filaments F
formed by the numerous spinning holes 13 and running downward from
the spinneret 12 pass. Downstream of the spinning tube 20, an
oiling means 17 is installed for applying an oiling agent to the
numerous filaments F coming from the filament passage 25 of the
spinning tube 20. Further, a first godet roller 14 and a second
godet roller 15 constituting a filament take-up means are installed
for taking up the numerous filaments F coming from the oiling means
17. Still further, a winding means 16 is installed for winding the
numerous filaments F coming from the filament take-up means. The
numerous filaments F are wound around a bobbin 16a as a yarn Y by
the winding means 16, to form a yarn package 16b.
[0096] The spinning tube 20 can be moved vertically by means of an
elevator 26 installed outside. The elevator 26 comprises a
vertically extending and rotatable column 26d provided with a ball
screw 26b, a motor 26c for rotating the column 26d, and a spinning
tube support arm 26a connected at one end with the ball screw 26b,
to be able to move vertically along the column 26d with the
rotation of the ball screw 26b, and connected at the other end with
the spinning tube 20. The elevator 26 is actuated to adjust the
distance between the bottom face of the spinneret 12 and the top
face of the spinning tube 20 to a desired value.
[0097] FIG. 5A is a bottom face view showing an example of the
spinneret 12 used in the apparatus of FIG. 4. The spinneret 12A of
FIG. 5A has numerous spinning holes 13 having a hole diameter of d
(mm). The numerous spinning holes 13 are arranged along a straight
line Z at a pitch of P (mm). Six spinning holes 13 are shown in
FIG. 5A. In the drawing, the distance between the center of the
rightmost spinning hole 13 and the center of the leftmost spinning
hole 13 is indicated by symbol dw.
[0098] FIG. 5B is a bottom face view showing another example of the
spinneret 12 used in the apparatus of FIG. 4. The spinneret 12B of
FIG. 5B has the spinning holes 13 of the spinneret 12A of FIG. 5A
in two rows, instead of one row. The spinnerets 13 are arranged
along straight lines Z1 and Z2 parallel to each other. The
positions of the spinning holes 13 on the straight line Z1 and the
positions of the spinning holes 13 on the straight line Z2 are
shifted from each other in the straight-line direction. This state
is shown in FIG. 5C as projected on the plane including the
straight-line direction and the direction of the vertical line to
the spinneret 12B. This state is necessary to ensure that the
numerous filaments F are disposed along one straight line without
overlapping each other in the case where air is injected obliquely
downward from outside the numerous filaments F toward the numerous
filaments in the spinning tube 20 described later. In FIG. 5B, the
centers of the respective spinning holes 13 are positioned on the
straight lines Z1 and Z2 respectively, and the distance between the
arrangement of the spinning holes 13 on the straight line Z1 and
the arrangement of the spinning holes 13 on the straight line Z2 is
the distance in the direction perpendicular to the straight lines
Z1 and Z2, and this distance is indicated by symbol W in FIG. 5B.
This distance W is the longest distance between the arrangement
lines of spinnerets, that is, in the case where the spinning holes
are arranged in 3 rows, the outermost two straight lines are
selected for referring to the distance W.
[0099] FIG. 5D is a bottom face view showing a further other
example of the spinneret 12 used in the apparatus of FIG. 4. In the
spinneret 12D of FIG. 5D, the spinning holes 13 are not arranged
regularly like straight lines on the surface of the spinneret. The
spinning holes 13 are arranged at random. This state is shown in
FIG. 5E as projected on the plane including the straight-line
direction and the direction of the vertical line to the spinneret
12D. This state is necessary to ensure that the numerous filaments
F are disposed along one straight line without overlapping each
other in the case where air is injected obliquely downward from
outside the numerous filaments F toward the numerous filaments in
the spinning tube 20 described later. In FIG. 5D, the distance
between the centers of the spinning holes 13 of the outermost
positions in the width direction (the direction perpendicular to
the longitudinal direction) of the spinneret 12D is indicated by
symbol W. In this case, it is preferred that the following relation
is satisfied. W.ltoreq.10 Ex where Ex is the length of the short
sides 21S of the rectangle as the cross sectional form of the
filament passage 25 of the spinning tube 20 described later.
[0100] As for the arrangement of the numerous spinning holes 13 in
the spinneret 12, they can also be arranged like a circle, though
such an arrangement is not illustrated in the drawings FIGS.
5A-5E.
[0101] In the case where the same number of spinning holes are
arranged in the spinneret, if the spinning holes are arranged in
plural rows, the length of the spinning tube 20 in the
straight-line Z direction can be shortened, and the flow rate Ef of
the air injected into the spinning tube 20 can be decreased, to
allow the reduction of operation cost. If the distance W between
the respective rows is too large, the discharged filaments F
composed of a polymer may be bent greatly, to make the produced
yarn irregular. It is preferred to keep the distance W between the
respective rows as small as possible, considering the phenomenon
that the filaments F are swollen at a position immediately below
the spinning holes 13.
[0102] The structure of the spinning tube 20 used in the apparatus
of FIG. 4 is explained below in reference to FIG. 6.
[0103] The spinning tube 20 comprises an air inlet section 22, an
air injection section 23, a steady flow section 21 and an air
discharge section 24 in this order from the upstream side toward
the downstream side. The spinning tube 20 has a filament passage 25
through which the numerous filaments F discharged from the spinning
holes 13 of the spinneret 12 run toward the filament take-up means
14, in the range from the air inlet section 22 to the air discharge
section 24.
[0104] The air injection section 23 has air injection holes 23a in
the wall faces of the filament passage 25 on both sides for
injecting air obliquely downward from outside the running numerous
filaments F toward the numerous filaments F. The air injection
holes 23a are connected with an air supply device 41, and
compressed air 41a is supplied to the air injection holes 23a. The
supplied compressed air 41a is injected into the filament passage
25 from the air injection holes 23a. The injection causes outside
air to be sucked from the top opening of the spinning tube 20 into
the air inlet section 22 in the filament passage 25, to form a
suction air flow. The sucked air and the air injected from the air
injection holes 23a flow toward the downstream side in the filament
passage 25 and become an airstream with a constant velocity in the
steady flow section 21. The air stream that has passed through the
steady flow section 21 is discharged outside from the air discharge
section 24. The air flow injected from the air injection holes 23a
causes the numerous filaments F entering the filament passage 25 to
be disposed in a straight line without overlapping each other in
the direction perpendicular to the paper surface in FIG. 6, and the
filaments as disposed like this run toward the oiling means 17.
[0105] The X-X sectional view of the spinning tube 20 shown in FIG.
6 is shown in FIG. 7. In FIG. 7, the cross sectional form of the
filament passage 25 is rectangular. The rectangular form is kept in
the range from the inlet of the filament passage 25 in the air
inlet section 22 to the outlet of the filament passage 25 in the
air discharge section 24.
[0106] The direction of the long sides 21L of the rectangle agrees
with the direction in which the spinning holes 13 of the spinneret
12 are arranged side by side. Therefore, the direction of the short
sides 21S of the rectangle is perpendicular to the direction in
which the spinning holes 13 of the spinneret 12 are arranged side
by side.
[0107] The length Ey of the long sides 21L of the rectangle as the
cross sectional form of the filament passage 25 is only required to
be larger than the distance dw (mm) between the outermost spinning
holes 13 of the spinneret 12A, 12B or 12D shown in FIG. 5A, 5B or
5D. Among the air inlet section 22, the air injection section 23,
the steady flow section 21 and the air discharge section 24, the
sizes of the respective rectangles may be different, and in this
case, it is only required that the smallest length of the long
sides 21L, 22L, 23L and 24L of the rectangles is larger than the
distance dw between the outermost spinning holes. However, it is
preferred that the sizes of the respective rectangles are equal
among the air inlet section 22, the air injection section 23, the
steady flow section 21 and the air discharge section 24.
[0108] On the other hand, in order that the running numerous
filaments F can be stably introduced into the filament passage 25,
it is more preferred that the following relation is satisfied:
[0109] Length Ey of the long sides of the rectangle>(Distance dw
between the outermost spinning holes+Pitch P of spinning holes)
Furthermore, in order that the air injected into the filament
passage 25 from the air injection holes 23a can act on the numerous
filaments F efficiently without waste, it is more preferred the
following relation is satisfied:
[0110] Length Ey of the long sides of the rectangle<(Distance dw
between the outermost spinning holes+Pitch P of spinning
holes.times.30)
[0111] If the length Ex of the short sides of the rectangle is too
small, the filaments are liable to clog the filament passage 25. It
is preferred that the respective short sides 21S, 22S, 23S and 24S
of the air inlet section 22, the air injection section 23, the
steady flow section 21 and the air discharge section 24 satisfy the
following relation:
[0112] Length Ex of the short sides of the
rectangle.ltoreq.(Diameter d of the spinning holes.times.3)
[0113] Moreover, in the steady flow section 21, if the length Ex of
the short side of the rectangle is too large, the running of the
numerous filaments F is destabilized. So, it is preferred that the
following relation is satisfied.
[0114] Length Ex of the short sides of the
rectangle.ltoreq.(Diameter d of the spinning holes.times.20)
[0115] In the apparatus shown in FIG. 6, the air inlet section 22
has a widened portion 22a. If the smallest value 22w (see FIG. 9)
of the short sides of the rectangle as the cross sectional form of
the filament passage 25 in the air inlet section 22 and the
smallest value 21w (see FIG. 9) of the short sides of the rectangle
as the cross sectional form of the filament passage 25 in the
steady flow section 21 are set to be different from each other, the
amount of the air sucked from outside in the air inlet section 22
can be set at a desired value.
[0116] In FIG. 6, the air injection section 23 has air injection
holes 23a for injecting air for the numerous filaments F running in
the filament passage 25, to form an air stream for ensuring that
the numerous filaments F are disposed in a straight line without
overlapping each other. The air injection holes 23a have an
injection angle of .theta. against the running direction of the
numerous filaments F, to ensure that the compressed air 41a flows
toward the air discharge section 24. It is preferred that the
injection angle .theta. is 45.degree. or less. If the injection
angle .theta. s more than 45.degree., the injected air may flow
toward the air inlet section 22, to disturb the running of the
numerous filaments F.
[0117] For enhancing the efficiency of suction of the numerous
filaments F into the passage 25 and reducing the size of the
spinning tube 20, it is preferred that the injection angle .theta.
be in a range of 5.degree. to 15.degree.. Furthermore, the
injection holes 23a are installed on the long sides of the filament
passage rectangular in the cross section shown in FIG. 7, but the
injection holes 23a can be slits extending in the full length of
the long sides 21L of the rectangle or arrangements of plural
circular holes 32a as shown as a perspective view in FIG. 8.
[0118] As shown in FIG. 9, the spinning tube 20 can also comprises
injection blocks 23b, 23c and the like that can be assembled and
disassembled. In this constitution, for example, the injection
angle .theta. of the injection holes, the slit width Ei of the
injection holes 23a (or the diameter of circular holes), and the
smallest values 21w or 22w of the short sides of the rectangle as
the cross sectional form of the filament passage 25 in the air
inlet section 22 or the steady flow section 21 can be easily
changed to suit desired operation conditions.
[0119] The air inlet section 22 has a widened portion 22a on the
most upstream side (the inlet of the filament passage 25) as shown
in FIG. 6. In this constitution, the sucked flow 42a of outside air
formed by the compressed air 41a injected from the injection holes
23a can be smoothly formed into the filament passage 25. The
widened portion 22a can be tapered or formed like a rounded
trumpet.
[0120] The air discharge section 24 has a widened portion 24a on
the most downstream side (the outlet of the filament passage 25) as
shown in FIG. 6. In this constitution, the compressed air 41a from
the air injection section 23 and the sucked flow 42a join to form a
running air stream 40, and after it has flowed through the steady
flow section 21, it becomes discharge-destined flow 43a at the
bottom end of the air discharge section 24, being discharged
outward from the filament passage 25. The widened portion 24a can
be tapered, but it is preferred that the widened portion is curved,
since the discharge-destined flow 43a can be smoothly discharged.
Furthermore, as shown in FIG. 9, if the bottom end portion of the
widened portion 24a is extended to have a predetermined length 24N
having a constant width 24w maintained, an effect of diffusing the
discharge-destined flow 43a can be obtained while the
discharge-destined flow 43a is kept regulated, to further stabilize
the numerous filaments F. On the other hand, it is also allowed
that the air discharge section 24 does not have the widened portion
24a. That is, the wall faces of the steady flow section 21 can
extend straight downward. In this constitution, the structure of
the spinning tube 20 can be simplified.
[0121] In the case where the discharge-destined flow 43a should
swing the filaments at or before the oiling means 17 (see FIG. 4)
installed downstream of the spinning tube 20, suction ports 46 can
be formed in the air discharge section 24 of the spinning tube 20
as shown in FIG. 10, to positively eliminate the discharge-destined
flow 43a from the suction ports 46 using a suction blower 45. In
this constitution, the discharge-destined flow 43a can be prevented
from flowing toward the downstream side of the bottom end of the
spinning tube 20.
[0122] As shown in FIG. 11, a discharge-destined flow suction means
47 connected with a suction blower 45 can also be installed
downstream of the bottom end of the spinning tube 20 and upstream
of the oiling means 17, for sucking the discharge-destined flow
43a. In this case, it is preferred that the cross sectional form of
the passage of the discharge-destined flow suction means 47 is
rectangular like the cross sectional form of the filament passage
25 of the spinning tube 20, and that suction faces 44a are formed
on the faces parallel to the direction in which the running
numerous filaments F are disposed side by side. It is also allowed
that the suction ports 46 are formed in the air discharge section
24 of the spinning tube 20 as shown in FIG. 10, and in addition,
that the discharge-destined flow suction means 47 is installed as
shown in FIG. 11.
[0123] In order to regulate the sucked flow 42a formed by the
spinning tube 20, as shown in FIG. 12, it is preferred to install
flow regulation sections 31 having, for example, honeycomb-like
grate members. In this constitution, the sucked flow 42a with a
predetermined direction can be formed, and a stable air stream can
be given to the running numerous filaments F.
[0124] The flow regulation sections 31 are only required to be such
that the grate members are installed in parallel to the direction
in which the running numerous filaments F are disposed side by
side, and if the cross sectional form of the passage in the flow
regulation sections 31 is rectangular like the filament passage 25
of the spinning tube 20, an air stream can be caused to act more
uniformly on the running numerous filaments F. Furthermore, one of
the grate members can be installed only on one side of the long
sides of the disposed numerous filaments F, but for stabilizing the
running of numerous filaments F more positively, it is preferred to
install the grate members on both sides of the disposed numerous
filaments F.
[0125] If each of the grate members comprises two grate components
31x and 31y overlaid on each other as shown in FIG. 13, the size of
the formed holes 31z can be adjusted to allow the flow rate of the
sucked flow 42a to be easily controlled. Furthermore, for smoothing
the sucked flow 42a, it is preferred that the top end of the air
inlet section 22 of the spinning tube 20 and the bottom end of the
flow regulation sections 31 are joined to be flush with each other
without any difference formed at a joint 29 of FIG. 12, to ensure
that the passage in the flow regulation sections 31 and the
filament passage 25 of the spinning tube 20 can be connected
smoothly.
[0126] As shown in FIG. 14, an air stream regulation means 30
having both the function of the flow regulation sections 31 shown
in FIG. 12 and the function of regulating the temperature of the
supplied air can also be installed upstream of the top end of the
spinning tube 20. The air stream regulation means 30 is connected
to a temperature-regulated air supply section 33. The air 32a
adjusted at a desired temperature supplied from the
temperature-regulated air supply section 33 is regulated by the
grate members of the flow regulation sections 31, and is positively
supplied to the running numerous filaments F. Since air adjusted at
a desired temperature is supplied, the numerous filaments F
existing before the spinning tube 20 are cooled, insulated or
heated, depending on the situation. In this constitution, the
temperature of the numerous filaments F can be controlled at a
desired temperature.
[0127] The air 32a can be supplied from both sides of the running
numerous filaments F, but it is preferred that the
temperature-regulated air is supplied to the numerous filaments F
from one side, while the air used is sucked from the other side. In
this constitution, the air stream formed in the spinning tube 20
can be controlled separately from the air stream formed by the air
stream regulation means 30. Furthermore, the volatile substance
generated from the numerous filaments F can also be sucked for
removal, and the contamination of the spinning tube 20 caused by
the volatile substance deposited on the inside of the spinning tube
20 can also be prevented.
[0128] On the upstream side of the top end of the spinning tube 20,
a temperature regulation means 35 can also be installed as shown in
FIG. 15 for controlling the temperature of the numerous filaments
F. The temperature regulation means 35 comprises a temperature
regulation pipe 37 shaped like a block, a rectangular temperature
regulation passage 35a formed inside the temperature regulation
pipe 37, and heating members 36 such as ceramic heaters installed
in the long side 37a direction to oppose the numerous filaments F
running in the temperature regulation passage 35a. The temperature
regulation means 35 is equipped with a temperature controller 38a
and a thermometer 38, for controlling the temperature of the
heating members 36, and as a result, the temperature of the
atmosphere in the temperature regulation passage 35a can be
controlled. In the case where the temperature regulation means 35
is used, the heating members 36 are installed in the direction in
which the numerous filaments F are disposed side by side in such a
manner that the faces of the long sides 37a of the temperature
control pipe 37 can be flush with the faces of the long sides 21L
of the steady flow section 21 of the spinning tube 20. The
temperature regulation means 35 can also be cylindrical in
appearance as shown in FIG. 16, if the temperature regulation
passage 35a of the temperature regulation pipe 37 through which the
numerous filaments F pass have a rectangular outlet 39a.
[0129] Both the air stream regulation means 30 shown in FIG. 14 and
the temperature regulation means 35 shown in FIG. 15 can also be
used together to control the temperature of the numerous filaments
F existing upstream of the top end of the spinning tube 20.
[0130] For the flow regulation sections 31 and the air stream
regulation means 30 shown in FIG. 14, and the temperature
regulation means 35 shown in FIG. 15, it is preferred that the top
end face of the air stream regulation means 30 or the temperature
regulation means 35 and the bottom end face of the spinneret 12 or
the spinning block 11 are connected with each other to achieve air
tightness, for preventing that the outside air flows through the
clearance between such a means and the spinneret 12 for disturbing
the air stream in the inside filament passage and to prevent that
the spinneret 12 is cooled.
[0131] As shown in FIG. 17, the air supply device 41 for the
spinning tube 20 shown in FIG. 6 and the suction ports 46 formed in
the air discharge section 24 shown in FIG. 10 (or the
discharge-destined flow suction means 47 shown in FIG. 11) can also
be connected with each other, to use the compressed air 41a
supplied to the spinning tube 20 in circulation. In this case,
before the compressed air 41a is supplied to the spinning tube 20,
an air controller 49 for controlling, for example, the temperature
and the flow rate should be installed, and the signal of the air
controller 49 should be used to adjust the opening of a valve 41y
of a supply pipe 41x, for example in the case where the flow rate
of the compressed air 41a is insufficient.
[0132] As shown in FIG. 17, in the case where the air stream
regulation means 30 is installed upstream of the top end of the
spinning tube 20, the air recovered from the suction ports 46 of
the air discharge section 24 (or the discharge-destined flow
suction means 47 shown in FIG. 11) can be fed through a bypass pipe
48 for supply again to the air stream regulation means 30 as supply
air 32a.
[0133] A mode in which a gas suction device is installed between
the spinneret and the spinning tube is described below.
[0134] FIG. 18 shows a spinning apparatus, in which a gas suction
device 60 is installed immediately below the spinneret 12, and the
spinning tube 20 spaced from the bottom end of the gas suction
device 60 is installed below the gas suction device 60. In FIG. 19,
the gas suction device 60 is installed between the spinneret 12 and
the spinning tube 20 detachably from the spinning apparatus. The
gas suction device 60 sucks the gas containing the volatile
substance generated from the numerous filaments F composed of a
polymer discharged from the spinning holes 13 of the spinneret
12.
[0135] The gas suction device 60 comprises suction buffers 61 and
gas suction ports 62 composed of gas permeable grate members. The
gas suction ports 62 are installed on both sides of the row of the
numerous filaments F composed of a polymer discharged from the
spinneret 12, to face the numerous filaments F in parallel to them.
The suction buffers 61 are connected with a gas suction blower 63
for carrying the gas sucked from the gas suction ports 62 to
outside the apparatus, through a volatile substance collection
filter 64. Thus the gas is sucked from the both sides of the row of
the numerous filaments F. In this constitution, swinging of the
numerous filaments F due to the suction can be reduced. The
volatile substance collection filter 64 removes the volatile
substance contained in the sucked gas, and the remaining gas is
discharged from the gas suction blower 63 to the atmosphere.
[0136] If the gas suction device 60 is positioned with its top face
kept as close to the bottom face of the spinneret 12 as possible,
the gas can be effectively sucked. However, if the top face of the
gas suction device 60 contacts the bottom face of the spinneret 12,
the gas suction device can cool the spinneret 12. So, it is
preferred that the clearance between the bottom face of the
spinneret 12 and the top face of the gas suction device 60 (the
distance between both in the vertical direction) expressed by SL
satisfies a relation of SL.ltoreq.2 mm.
[0137] The gas suction ports 62 are formed in planes parallel to
the row of the numerous filaments F. If the gas suction ports 62
are closer to the row of the numerous filaments F, the gas suction
efficiency is higher. However, if they are too close, the gas flow
caused by suction causes the numerous filaments F to be swung
greatly, and it may happen that the numerous filaments F are fused
to each other. If the suction distance from the gas suction ports
62 to the row of the numerous filaments F is PL, it is preferred to
satisfy a relation of 2 mm.ltoreq.PL.ltoreq.20 mm.
[0138] It is desirable to use flow regulation members low in gas
flow resistance such as honeycomb members as the gas suction ports
62 for regulating the flow of sucked gas.
[0139] The amounts of sucked gas can be adjusted to desired flow
rates by means of the suction adjusting valves 65. It is desirable
to use flow meters 66 provided for measuring both the flow rates,
to equalize the flow rates of the gas sucked by both the suction
ports 62. In this constitution, the numerous filaments F can be
prevented from swinging. The flow rate can be controlled easily
based on the correlation between the values indicated by a negative
pressure gauge 67 and the gas velocities measured beforehand at the
gas suction port 62.
[0140] Since the running speed of the numerous filaments F running
immediately below the spinneret 12 is small, the moving velocity of
the gas generated from the numerous filaments F running immediately
below the spinneret 12 is also small. So, the gas suction velocity
can be very small. Though depending on the distance between the gas
suction ports 62 and the numerous filaments F, it is preferred that
the gas suction velocity is in a range of 5 m/min to 30 m/min.
Since the running speed of the numerous filaments F on the more
downstream side is higher, it is desirable to adjust the gas
suction ports 62 for ensuring that the suction flow rates on the
downstream side become higher than those on the upstream side in
the gas suction device 60. In this constitution, the gas
accompanying the running numerous filaments F can be efficiently
collected.
[0141] If the gas suction device 60 sucks the gas existing around
the numerous filaments F, there occurs a phenomenon that the
outside air is sucked from the surrounding. In this phenomenon, the
incoming outside air lowers the temperature around the spinneret
12, and as a result, the spinnability may be impaired.
[0142] To prevent this phenomenon, it is desirable to install a
heat insulating plate 12L below the bottom face of the spinneret 12
as shown in FIG. 20.
[0143] As another means, it is desirable to keep the suction
buffers 61 of the gas suction device 60 spaced from the spinneret
12 as shown in FIG. 21. This can be achieved if the top faces of
the suction buffers 61 are kept in contact with the bottom face of
the spinning block 11 directly or indirectly through a packing lip.
As a further other means, for example, the clearance between the
bottom face of the spinning block 11 and the top faces of the
suction buffers 61 can be perfectly closed by means of the packing
11p. In this constitution, the space between the bottom face of the
spinneret 12 and the top face of the gas suction device 60 is kept
gas-tight.
[0144] FIG. 22 is a sectional view of the suction device 60 in the
direction perpendicular to the direction vertical to the bottom
face of the spinneret 12 (the direction perpendicular to the
running direction of the numerous filaments F in the case where the
numerous spinning holes 13 of the spinneret 12 are arranged on one
straight line).
[0145] In the case where the gas suction device 60 sucks the
outside air from both the lateral sides 62a open to the outside air
of the gas suction ports 62, it can happen that the gas suction
device 60 sucks the gas positioned around the filaments F running
on both lateral sides of the numerous filaments F more strongly
than the gas positioned around the filaments F running inside among
the numerous filaments F. In this case, the produced numerous
filaments constituting a yarn become different from each other
(irregular) in properties. To avoid this phenomenon, it is
desirable to close both the lateral sides open to the outside air
of the gas suction ports 62 using side plates 68.
[0146] For the outside air flowing in from the bottom openings of
the gas suction device 60, it is desirable to install flow
regulation sections 31 each having a honeycomb grate member 88 as
shown in FIG. 24, between the bottom face of the gas suction device
60 and the top face of the spinning tube 20, for regulating the
inflow direction.
[0147] In FIG. 23, the outside air 81a incoming from suction spaces
80 forms an ascending stream against the running direction of the
numerous filaments F. Because of the ascending stream, the gas
otherwise destined to flow down accompanying the running numerous
filaments F is turned toward the gas suction device 60, and
collected by the gas suction device 60. As a result, the inflow of
the gas generated near the spinneret 12 into the spinning tube 20
installed downstream of the gas suction device can be
prevented.
[0148] If the flow regulation sections 31 each having the suction
space 80 is installed between the bottom end of the gas suction
device 60 and the top end of the spinning tube 20, the sucked flow
42a caused by the spinning tube 20 is also regulated in the
downstream portion in the flow regulation sections 31. In this
constitution, the sucked flow 42a directed as desired is allowed to
flow into the filament passage 25 of the spinning tube 20. Thus, a
stable air stream with a small volatile matter content flows into
the filament passage 25 of the spinning tube 20.
[0149] It is preferred that the flow regulation sections 31 are
provided with grate members 88 arranged with their longitudinal
direction kept in parallel with the direction in which the running
numerous filaments F are disposed side by side. The cross sectional
form of the filament passage in the flow regulation sections 31 can
be rectangular like the cross sectional form of the filament
passage 25 in the spinning tube 20. In this constitution, the air
stream can be caused to more uniformly act on the running numerous
filaments F.
[0150] It is preferred that the suction spaces 80 of the flow
regulation sections 31 are provided on both sides of the disposal
of the numerous filaments F, to further stabilize the running of
the numerous filaments F.
[0151] It is only required that the grate members 88 installed in
the flow regulation sections 31 are installed to ensure that the
air streams are regulated in the direction perpendicular to the
direction in which the numerous filaments F are disposed side by
side, in planes perpendicular or inclined to the disposal faces of
the numerous filaments F (for example, the disposal faces of the
numerous filaments F formed by the row of spinning holes indicated
by the straight line Z in FIG. 5A). The inclination angle can also
change from the top ends to the bottom ends of the grate members
88.
[0152] FIG. 24 is a perspective view showing either of the grate
members 88 used in the flow regulation sections 31 and also the
thickness 88t of the grate member 88 in the flow regulation
direction. If the thickness 88t in the flow regulation direction is
larger, the flow regulation effect is higher. It is preferred that
the grate member 88 is formed to have a thickness 88t of 5 mm or
more.
[0153] The flow regulation sections 31 can also be connected with a
blower 33 as shown in FIG. 25. The blower 33 positively supplies
air to the flow regulation sections 31 of the suction spaces 80, to
assist the flow of the outside air 81a flowing toward the suction
device 60 and the flow of the sucked flow 42a flowing toward the
spinning tube 20. Depending on the kind, condition or the like of
the polymer constituting the running filaments, an inert gas such
as nitrogen can also be introduced. Hot air or cold air can also be
introduced to control the temperature of the air acting on the
numerous filaments F.
[0154] In the production of a yarn, it can happen that a filament
is broken. An example of how to deal with the situation is
described below in reference to FIG. 26. In FIG. 26, in order to
monitor the running passage of the yarn Y, a filament break sensor
96 is installed between the second godet roller 15 and the winding
means 16. When a filament is broken, the filament break sensor 96
detects it and issues a filament break detection signal. On the
other hand, a sucker 95 is installed between the spinning tube 20
and the oiling means 17, to face the running passage of the yarn Y
consisting of numerous filaments F. The sucker 95 is connected with
a waste yarn blower 94. If the waste yarn blower 94 is actuated
based on a filament break detection signal, the sucker 95 sucks the
yarn Y.
[0155] Even if a filament is broken, the numerous filaments F
continuously formed by the spinning holes 13 of the spinneret 12
keep running on the upstream side of the position where the
breaking has occurred. The numerous filaments F continuously
running from the spinneret 12 are sucked and taken up by the waste
yarn blower 94 and the sucker 95 respectively actuated based the
filament break detection signal issued by the filament break sensor
96 when the sensor has detected the breaking. Then, the yarn taken
up by the sucker 95 is discharged from the sucker 95 and
accommodated in a waste yarn container 97. In this constitution,
the winding of the yarn around the first godet roller 14 and the
second godet roller 15 is prevented. It is preferred that the
sucker 95 is installed in such a manner that it opens toward the
air discharge section 24 of the spinning tube 20 and can move
horizontally in the direction in which the numerous filaments F are
disposed side by side (the long side direction of the filament
passage 25 of the spinning tube 20).
[0156] Next, the yarn production method of the invention is
described below in reference to FIGS. 4 and 6.
[0157] The air supply device 41 injects the compressed air 41a
obliquely downward into the filament passage 25 of the spinning
tube 20 from the injection holes 23a. As a result, the air stream
40 running downward in the filament passage 25 is formed. The
spinning tube 20 is installed below the spinneret 12 in the
vertical direction in such a manner that the numerous filaments F
composed of a polymer discharged as a row(s) from the numerous
spinning holes 13 of the spinneret run straight downward in the
vertical direction through the filament passage 25 of the spinning
tube 20.
[0158] With this arrangement, when the running numerous filaments F
have arrived at the inlet of the filament passage 25, the sucked
flow 42a formed in the air inflow section 22 allows the filaments F
to be easily introduced into the filament passage 25, and further
allows the filaments F to easily pass through the filament passage
25. If the elevator 26 is actuated to lower the spinning tube 20,
the filaments F run stably and can easily pass through the filament
passage 25.
[0159] A flowable polymer is discharged from the numerous spinning
holes 13 arranged in a row(s) in the spinneret 12 provided in the
spinning block 11. The discharged polymer forms numerous filaments
F disposed in accordance with the arranged spinning holes 13. The
formed numerous filaments F are introduced into the inlet of the
filament passage 25, and are discharged from the outlet of the
filament passage 25. The polymer constituting the numerous
filaments F loses its flowability and is solidified while it passes
through the filament passage 25 of the spinning tube 20.
Subsequently, while being sucked by a suction gun (not
illustrated), the filaments F discharged from the filament passage
25 are fed along the oiling means 17, the first godet roller 14 and
the second godet roller 15 sequentially, finally being wound by the
winder 16. Thus, the initial work in the production of yarn Y is
completed. In the case where the spinning tube 20 used has the
suction ports 46 shown in FIG. 10, the operation of the suction
blower 45 connected with the suction ports 46 is suspended till the
yarn installation work up to the winder 16 is completed, and after
the yarn installation work has been completed, the suction blower
45 is actuated.
[0160] Thereafter, the polymer is continuously discharged from the
spinning holes 13 of the spinneret 12, to form numerous filaments
F. From the injection holes 23a formed in the spinning tube 20
toward the filament passage 25, air streams are injected obliquely
downward toward the formed numerous filaments F on both sides of
the numerous filaments F. Receiving the air streams, the numerous
filaments F are disposed in one row without overlapping each
other.
[0161] Subsequently, the disposed numerous filaments F run downward
in the filament passage 25 with the disposal maintained. On the
other hand, the air streams injected from the injection holes 23a
obliquely downward into the filament passage 25 for contribution to
the maintenance of the disposal of the numerous filaments F form a
downward running air stream 40 in the filament passage 25. In the
filament passage 25, the downward running numerous filaments F and
the downward running air stream 40 coexist. The coexistence of the
running numerous filaments F and the running air stream 40 in the
filament passage 25 allows that the numerous filaments F composed
of a polymer discharged from the spinning holes 13 are stably drawn
and made thinner. As a result, a high elongation yarn Y having
little irregularity among the filaments can be produced at a high
speed.
[0162] According to the yarn production process, the numerous
filaments F composed of a polymer discharged from the spinning
holes 13, not yet solidified, are introduced into the filament
passage 25 of the spinning tube 20, and are drawn and made thinner
there. Therefore, unlike a nonwoven fabric obtained by cooling and
solidifying the numerous filaments composed of a polymer discharged
from the spinning holes and drawing them with an air stream, a high
elongation yarn having little irregularity among the filaments can
be produced.
[0163] In this yarn production process, since the injection
velocity Vs of the compressed air 41a from the injection holes 23
is set at a value higher than the take-up speed Vw of the yarn Y by
the first godet roller 14, the velocity of the air running together
with the numerous filaments F is kept at higher than the running
speed of the numerous filaments F at least in part of the filament
passage 25 of the spinning tube 20. In this state, the drawing
force by the air stream flowing downward in the filament passage 25
acts on the numerous filaments F.
[0164] In this yarn production process, to generate a more
preferred drawing force, it is preferred that the running velocity
Ve of the running air stream 40 flowing in the steady flow section
21 is kept at not less than a velocity of 60% of the yarn take-up
speed Vw.
[0165] In the case where the running velocity Ve of the running air
stream 40 is too high, the running state of the yarn Y near the
oiling means 17 positioned below the spinning tube 20 may be
adversely affected. One of the unwanted effects is filament
breaking. To prevent such an accident, it is preferred that the
running velocity Ve of the running air stream 40 is not more than a
velocity of 120% of the yarn take-up speed Vw.
[0166] The speed Vf of the filaments F composed of a polymer
discharged at an initial speed of Vo from the spinning holes 13
becomes gradually higher with the increase of distance from the
spinneret 12 in the vertical direction, and it reaches the yarn
take-up speed Vw at a certain point.
[0167] This relation is shown in FIG. 27. In the graph of FIG. 27,
the distance from the bottom face of the spinneret 12 in the
vertical direction is chosen as the abscissa, and the speed of the
filaments F at each distance from the bottom face of the spinneret
12 in the vertical direction is chosen as the ordinate. The speed
of the filaments F changes as shown by curve A in the graph of FIG.
27. In this case, if the distance from the bottom face of the
spinneret 12 to the point where the speed of the filaments F
reaches the yarn take-up speed Vw is Lg, and the distance from the
bottom face of the spinneret 12 to the point where the gradient of
the curve A becomes largest, i.e., the point where the acceleration
of filaments F becomes largest, is La, then it is preferred that a
relation of La.ltoreq.Lg/2 is satisfied. This relation can be
realized if the position of the spinning tube 20 to the spinneret
12, the polymer discharge condition from the spinneret 13, the
condition of running air stream 40 and the yarn take-up condition
are adjusted. In the case where the relation of La.ltoreq.Lg/2 is
satisfied, the filaments F can be made thinner in the upstream
region in the filament passage 25. This constitution facilitates
the production of a non-oriented yarn Y, i.e., a high elongation
yarn Y.
[0168] In the case where the flow regulation sections 31 are
installed upstream of the spinning tube 20 as shown in FIG. 12, the
outside air flowing from outside into the air inlet section 22 is
regulated in flow. In this constitution, regulated sucked flow 42a
is formed, and in this state, the sucked flow 42a can be given to
the numerous filaments F running as a row in the direction to cross
them. This state exhibits an effect of uniformly cooling the
numerous filaments F. Thus, a yarn Y having little yarn
irregularity can be easily produced.
[0169] In the case where the air stream regulation means 30 is
installed upstream of the spinning tube 20 as shown in FIG. 14, the
atmosphere temperature upstream of the spinning tube 20 can be
positively controlled. As shown in FIG. 15, in the case where the
temperature regulation means 35 contained in the temperature
regulation pipe 37 is installed upstream of the spinning tube 20,
the atmosphere in the temperature regulation passage 35a through
which the numerous filaments F run can be controlled by radiation
heat. This allows the temperature of the numerous filaments F
entering the spinning tube 20 to be controlled at a desired
temperature. This temperature control facilitates the production of
a yarn Y having desired physical properties.
[0170] It is preferred that the temperature of the filaments F
entering the filament passage 25 of the spinning tube 20 is
160.degree. C. or higher. A more preferred temperature is
200.degree. C. or higher. If the temperature of the filaments F is
controlled to such a temperature, the injection flow rate Ef of the
air injected into the filament passage 25 from the air supply
device 41 can be decreased to lower the production cost of the yarn
Y.
[0171] In the case where a filament is broken while the yarn Y is
produced, the filament break sensor 96 detects the filament
breaking as shown in FIG. 26, and the drive of the drive system
ranging from the first godet roller 14 to the winder 16 is stopped.
At the same time, the waste yarn blower 94 is actuated, and the
waste yarn sucker 95 sucks the filaments coming from the filament
passage 25 as waste filaments F1 while being reciprocated in the
direction in which the numerous filaments F are disposed side by
side (horizontal direction). It is preferred that while the
filament breaking situation is dealt with like this, the injection
flow rate Ef of the compressed air 41a into the spinning tube 20 is
decreased more or less compared with the normal flow rate.
[0172] As shown in FIG. 29, in the case where there are plural yarn
production lines, if the respective rotation axes J1, J2 and J3 of
the first godet rollers 14, the second godet rollers 15 and the
winding means 16 are kept in parallel with the direction in which
the spinnerets 12 and the spinning tubes 20 are arranged side by
side, it can be prevented that the yarns Y introduced along the
first godet rollers 14 are twisted. This allows the yarns Y to be
stably taken up.
[0173] When the numerous filaments F are oiled, the numerous
filaments F can be bundled as one yarn, but instead, as shown in
FIG. 28, an oiling means consisting of a long oil supply roller 17a
and an oil coating member 17b for applying an oil to the oil supply
roller 17a can also be used for applying an oil to each of the
filaments.
[0174] As shown in FIG. 30, the spinneret installed in the spinning
block 11 can also have plural spinning hole groups 13a, each
consisting of plural spinning holes 13, arranged in one direction.
As shown in FIG. 31, instead of using one spinneret to be installed
in the spinning block 11, plural spinnerets 12 arranged in one
direction, each having plural spinning holes 13 arranged in the
same one direction, can also be used.
[0175] In this case, the plural yarns YY can pass through one
spinning tube 20, and further along the roller 17a of one oiling
means.
[0176] In this case, in the relation between the passage width Eyy
in the longitudinal direction, of the filament passage 25 of this
spinning tube 20 and the passage width Ey for one spinneret 12
described before (for one yarn), Eyy corresponds to
(Ey).times.(number of yarns).
[0177] According to the yarn production method of the invention,
the properties of the yarn obtained at a production speed of 3,000
m/min or 4,000 m/min by a conventional method can be realized even
at a speed of 5,000 m/min or more. The production speed can also be
6,000 min/min to 10,000 m/min even in the case where it is intended
to obtain a yarn with similar properties.
[0178] Even in a process in which the yarn Y is heated by the first
godet roller 14 and drawn between the first godet roller 14 and the
second godet roller 15 with the speed of the second godet roller 15
kept higher than the speed of the first godet roller, a similar
effect can be obtained.
[0179] The yarn production method of the invention satisfies both
the quality and productivity of the obtained yarn in good balance,
compared with the yarn production methods of the prior art.
Therefore, the yarn production method of the invention can also be
used, for example, for producing a very thin yarn with a filament
fineness of 0.5 dtex or less difficult in the control of yarn
quality, and also for producing a monofilament.
[0180] Another embodiment of the yarn production method of the
invention is described below in reference to FIGS. 6, 18 and
19.
[0181] The gas suction blower 63 is operated to produce a state in
which the gas suction device 60 can suck the gas in the filament
passage in the gas suction device 60. On the other hand, the air
supply device 41 is operated to inject the compressed air 41a into
the filament passage 25 of the spinning tube 20 from the two
injection holes 23a opened to face each other in the filament
passage 25, and the air streams injected from both the injection
holes 23a collide with each other in the filament passage 25, to
form a air stream 40 running downward in the filament passage
25.
[0182] The spinning tube 20 is positioned below the spinneret 12 in
the vertical direction, to ensure that the numerous filaments F
composed of a polymer discharged as a row from the spinning holes
13 of the spinneret 12 can run straight downward in the vertical
direction, to pass through the filament passage 25 of the spinning
tube 20.
[0183] With this arrangement, when the running numerous filaments F
reach the inlet of the filament passage 25, the sucked flow 42a
formed in the air inlet section 22 allows the filaments F to be
easily introduced into the filament passage 25, and facilitates
further passage of the filaments F through the filament passage 25.
If the elevator 26 is actuated to move the spinning tube 20 further
downward from the spinneret 12, the filaments F are progressively
cooled and solidified, to facilitate their passage through the
filament passage 25, and at the same time, the gas near the
spinneret 12 generated from the filaments F is sucked into the
filament passage 25 of the spinning tube 20 and discharged outside
in the time zone before start of normal operation (before yarn
threading). So, the contamination in the spinning tube 20 by the
gas containing the volatile substance can be avoided. Furthermore,
the running of the filaments F can be stabilized to allow easy
passage through the filament passage 25.
[0184] The gas suction device 60 can also be connected at the top
of the spinning tube 20, to ensure that it can be lowered or lifted
together with the spinning tube 20. On the other hand, if the gas
suction device 60 is separate from the spinning tube 20 and
installed on the under face of the spinning block 11 or the
spinneret 12, the clearance of the suction spaces 80 (FIG. 23) can
be easily adjusted at a desired distance by lifting or lowering the
spinning tube 20.
[0185] Then, a polymer is discharged from the spinning holes 13
arranged in a row in the spinneret 12 installed in the spinning
block 11, to form numerous filaments F. The formed numerous
filaments F pass through the filament passage 25 of the gas suction
device 60 and the spinning tube 20. The running filaments F are
solidified while they pass through the filament passage 25 of the
spinning tube 20. Subsequently, the solidified filaments F are
sucked by a suction gun (not illustrated), and guided along the
oiling means 17, the first godet roller 14 and the second godet
roller 15 sequentially, being finally wound by the winder 16. Thus,
the initial work in the production of the yarn Y is completed.
[0186] Thereafter, the polymer is discharged continuously from the
spinneret 12, to form numerous filaments F, and the formed numerous
filaments F run downward in the filament passage 25 of the gas
suction device 60 and the spinning tube 20 with their disposal
maintained. During this time, the gas suction device 60 sucks the
gas generated from the filaments F. In spite of the suction, the
compressed air 41a injected from the injection holes 23a acts on
the numerous filaments F running through the filament passage 25 of
the spinning tube 20, and the numerous filaments F are aligned
along a straight line without overlapping each other. The numerous
filaments F running in the filament passage 25 are cooled and
solidified while they pass through the filament passage 25. The
cooled and solidified numerous filaments F are bundled and oiled by
the oiling means 17. The oiled numerous filaments F are guided as
the yarn Y along the first godet roller 14 and the second godet
roller 15, being wound around a bobbin by the winder 16. Thus, the
yarn Y is produced as a yarn package.
[0187] This yarn production method satisfies both yarn quality and
yarn productivity in good balance compared with the yarn production
processes of the prior art. The yarn production process can also be
used for producing a yarn consisting of numerous filaments composed
of any of various polymers such as polypropylene and polylactic
acid. This yarn production process can be used for producing a very
thin yarn with a filament fineness of 0.5 dtex or less, or
difficult in the control of yarn quality, and also for producing a
thick yarn such as a monofilament.
[0188] A first group of Examples and Comparative Examples:
[0189] As examples of the yarn production method of the invention,
yarn production methods using the yarn production apparatus shown
in FIG. 4 are described below, and as comparative examples, yarn
production methods using the apparatus shown in FIG. 1 are
described. The production conditions used in the examples and
comparative examples are shown in the following respective
tables.
[0190] The spinning tube 20 used in Examples 1 through 13 is shown
in FIG. 6. The cross sectional view of the spinning tube 20 and its
filament passage 25 is shown in FIG. 7. The cross sectional form of
the filament passage 25 is rectangular. The spinning tube 20 had
the air inlet section 22, the air injection section 23, the steady
flow section 21 and the air discharge section 24, to name from the
top end to the bottom end. The air inlet section 22 had a widened
portion 22a, and the air discharge section 24 had a widened portion
24a. The length Ex of the short sides 21S in the cross section of
the filament passage 25 in the steady flow section 21 was 2 mm, and
the length Ey of the long sides 21L was 100 mm. The injection holes
23a open on the wall faces of the filament passage 25 respectively
had a form of a slit extending over the full length of the long
sides 21L of the filament passage 25. The slit width Ei (see FIG.
9) of the slits was 0.4 mm.
[0191] It is difficult to directly measure the injection velocity
Vs (m/min) of the compressed air 41a injected from the injection
holes 23a of the air injection section 23. Therefore, the value
obtained by calculation from the injection flow rate Ef (m3/min) of
the compressed air 41a supplied from the blower of the air supply
device 41, the cross sectional area of the passage of each
injection hole 23a (Ey.times.Ei) and the supply pressure of the
compressed air 41a was employed as the injection velocity Vs
(m/min).
[0192] The running air stream velocity Ve (m/min) of the running
air stream 40 flowing in the steady flow section 21 was obtained
from the following formula based on the differential pressure Po
between the respective pressures obtained from the pressure pipe P1
installed in the wall of the steady flow section 21 and the
pressure pipe P2 installed in the downstream region of the air
discharge section 24. Ve=(2.about.Po/p).sup.1/2 where p is the
density of air.
[0193] The filament speed Vf (m/min) of the filaments F running
between the spinneret 12 and the first godet roller 14 was measured
using the measuring instrument shown in FIG. 32. In FIG. 32, a
laser Doppler yarn velocimeter 50 consisted of a measuring head 51
and a controller 52. The measuring head 51 was moved in the running
direction of the filaments F, and the filament speed Vf (m/min) of
the filaments F running between the spinneret 12 and the first
godet roller 14 was measured at every 100 mm position from the
spinneret 12. To measure the filament speed of the filaments F
running through the filament passage 25 in the spinning tube 20,
the spinning tube 20 was partially opened at a portion
corresponding to one short side 21b of the filament passage 25 so
that the laser beam could reach the inside of the filament passage
25 from the measuring head 51 when the yarn speed was measured. In
the case where the opening affects the air stream of the filament
passage 25, the opening should be given up, and a small hole for
allowing the transmission of the laser beam for measurement should
be formed in the spinning tube 20 at a portion corresponding to one
short side 21S of the filament passage 25. As another method, a
portion of the spinning tube 20 corresponding to one short side 21S
of the filament passage 25 should be made of a material capable of
transmitting the laser beam for measurement, to allow measurement
through the portion.
[0194] In FIG. 4, L1 (mm) indicates the distance from the bottom
face of the spinneret 12 to the top face of the spinning tube 20,
and defines the spinning tube position. L2 (mm) indicates the
overall length of the spinning tube 20, and defines the spinning
tube length. L3 (mm) indicates the distance from the bottom face of
the spinneret 12 to the oiling means 17, and defines the oiling
position. L4 (mm) indicates the distance from the bottom face of
the spinneret 12 to the first godet roller 14, and defines the
take-up position. Vw (m/min) indicates the yarn Y take-up speed by
the first godet roller 14. In FIG. 6, Es (mm) indicates the
distance from the top face of the spinning tube 20 to the injection
holes 23a of the air injection section 23 (the center of the open
faces of the injection holes 23a in the vertical direction on the
wall faces of the filament passage 25), and defines the slit
position.
[0195] In the spinneret 12, the distance between the respectively
adjacent spinning holes 13 is expressed as the spinning hole pitch
P (mm), and the hole diameter of the spinning holes 13 on the
bottom face of the spinneret 12 is expressed as the spinning hole
diameter d (mm) . The center distance between the two spinning
holes most apart from each other among the plural spinning holes 13
is expressed as distance dw (mm) between the outermost spinning
holes.
EXAMPLES 1, 2, 3 and 4
[0196] The apparatus shown in FIG. 4 was used to produce polyester
yarns Y each consisting of 36 filaments F with a filament fineness
D of 135 dtex under the conditions shown in Table 1. The spinneret
12 used had all the spinning holes 13, i.e., 36 spinning holes 13
arranged on a straight line Z as shown in FIG. 5A. The spinning
hole pitch P was 2.5 mm and the spinning hole diameter d was 0.3
mm. The distance dw between the outermost spinning holes was 90.3
mm. In Examples 1, 2, 3 and 4, the same conditions were employed
except that the spinning tube position L1 was changed. The yarn
production conditions and the properties of the obtained yarns are
shown together in Table 1 given later.
[0197] In every example, the swing of the 36 filaments F running
upstream and downstream of the spinning tube 20 was small, and a
good spinning state could be observed. It was confirmed that the 36
filaments F maintained their disposal obtained immediately after
they had been discharged from the spinneret 12, in the range from
the upstream side of the spinning tube 20 to the outlet of the
spinning tube 20, and passed through the spinning tube 20 without
being converged (without contacting each other).
[0198] The results of yarn quality evaluation of the yarn Y wound
by the winding means 16 are shown in Table 1. The yarn properties
in Example 1 were 141% in elongation E, 2.4 g/dtex in strength T
and 0.95 in yarn irregularity U%. Those in Example 2 were 128% in
elongation E, 2.6 g/dtex in strength and 0.93 in yarn irregularity
U%. Those in Example 3 were 104% in elongation E, 2.8 g/dtex in
strength T and 1.00 in yarn irregularity U%. Those in Example 4
were 86% in elongation E, 3.0 g/dtex in strength T and 1.13 in yarn
irregularity U%. There was a tendency that when the spinning tube
20 was farther away from the spinneret 12, the elongation E of the
obtained yarn Y was smaller while the yarn irregularity U% became
larger.
[0199] The filament velocity Vf of the running filaments F was
measured at every 100 mm position from the spinneret 12, and the
results are shown in FIG. 33. The distance from the spinneret 12 to
the point at which the solidified filaments F reached the take-up
speed Vw was identified as the take-up speed reaching point Lg, and
the distance from the spinneret 12 to the middle point between the
two points of the largest gradients in the curve formed by
connecting the measuring points was identified as the acceleration
point. The results of these points in the respective examples are
shown in Table 2 given later.
[0200] From FIG. 33, it can be seen that the position of the
acceleration point La (acceleration points La1 to La4) shifted
toward the downstream side as the value of the spinning tube
position L1 became larger. It also can be seen that the position of
each acceleration point La was on the upstream side of the one half
of the distance to the corresponding reaching point Lg (reaching
points Lg1 to Lg4). In Examples 1 through 4, the respective
acceleration points La were 28%, 39%, 45% and 50% of the reaching
points Lg. From the results, it was found that if the relation of
acceleration point La<reaching point Lg/2 is satisfied and the
ratio of the acceleration point La to the reaching point Lg is
lower, then the elongation E of the produced yarn Y becomes
higher.
[0201] The temperature Ti(0.degree. C.) of the filaments F at right
above the air inlet section 22 of the spinning tube 20 was measured
using a non-contact type thermometer in each example. The results
are shown in Table 2. The temperatures Ti in the respective
examples were 215.degree. C. in Example 1, 203.degree. C. in
Example 2, 184.degree. C. in Example 3 and 158.degree. C. in
Example 4. The results mean that if the value of the spinning tube
position L1 is smaller, the filaments with a higher temperature
enter the spinning tube 20.
[0202] While the filaments F are kept at a high temperature, the
filaments F encounter the compressed air 41A injected obliquely
downward toward the running direction of the filaments F from the
injection holes 23a, and thereafter, together with the running air
stream 40 running downward in the filament passage 25, the
filaments run downward in the filament passage 25. The coexistence
of the filaments F and the running air stream 40 allows the
produced yarn Y to have a higher elongation. The yarn Y obtained
like this can have an elongation of not less than 1.5 times the
elongation of the yarn obtained in Comparative Example 1 described
later.
[0203] In the relation between the spinning tube range Le (mm) in
which the spinning tube 20 exists (the range from the bottom face
of the spinneret 12 to L1 or L1+L2) and the running air stream
velocity vV, as shown in Table 2, the respective acceleration
points La are within the spinning tube range Le in Examples 1
through 4, and the values VL of the filament speed Vf at the
acceleration points La are smaller than the values of the running
air stream velocity Ve. This means that at least partially in the
spinning tube 20, the drawing force of the running air stream 40
acted on the filaments F.
COMPARATIVE EXAMPLES 1, 2 and 3
[0204] The apparatus shown in FIG. 1 was used to produce polyester
yarns Y each consisting of 36 filaments F with a filament fineness
D of 135 dtex under the conditions shown in Table 3. In the
respective comparative examples, the spinneret 1 shown in FIG. 2
was used. The spinneret 1 had 36 spinning holes 6 so arranged
within a circle having a diameter dd of 72 mm that the filaments
discharged from the holes should not contact each other. The
cooling means 3 shown in FIG. 1 supplied cooling air 3a to the
downward running filaments F composed of a polymer discharged from
the spinning holes 6 of the spinneret 1, in the direction
perpendicular to the vertical direction. The filament cooling
length L22 in the cooling means was 1,000 mm, and the cooling air
velocity Vc1 of the cooling air 3a was 30 m/min. The cooling air 3a
was blown from the cooling air blow face of the cooling means 3 and
crossed the running filaments F, then being sent substantially in
the same direction as the blow direction and discharged out of the
cooling means 3. Therefore, there was no air stream that ran in the
running direction of the filaments F and dominated the running
filaments F.
[0205] In FIG. 1, L11 (mm) indicates the distance from the bottom
face of the spinneret 1 to the top face of the cooling means 3, and
defines the cooling means position. Comparative Examples 1, 2 and 3
employed the same conditions except that the yarn take-up speed Vw
was changed. The yarn production conditions and the properties of
the obtained yarns in these comparative examples are shown together
in Table 3 given later.
[0206] In every comparative example, the swing of the running 35
filaments upstream and downstream of the cooling means 3 was small.
However, it was confirmed that the cooling air 3a crossing the
filaments F in the direction substantially perpendicular to the
running direction of the filaments F bent the running filaments F.
The bending degree was different from filament to filament
depending on the respective running positions resulting from the
positions of the arranged spinning holes 6.
[0207] The results of yarn quality evaluation of the yarns Y wound
by the winding means 5 are shown in Table 3. The yarn properties in
Comparative Example 1 were 65% in elongation E, 3.1 g/dtex in
strength T and 1.24 in yarn irregularity U%. Those in Comparative
Example 2 were 98% in elongation E, 2.9 g/dtex in strength T and
1.13 in yarn irregularity U%. Those in Comparative Example 3 were
119% in elongation E, 2.7 g/dtex in strength T and 1.05 in yarn
irregularity U%. It was confirmed that when the yarn take-up speed
Vw was higher, the elongation E of the produced yarn was
smaller.
[0208] In comparison with Examples 1 through 4, the examples could
produce high strength yarns even at a yarn take-up speed Vw of
5,000 m/min. Especially Example 1 could produce a yarn with an
elongation higher than that of Comparative Example 3 in which the
take-up speed Vw was 3,500 m/min.
[0209] The filament speed Vf of the running filaments F was
measured at every 100 mm position from the spinneret 1, and the
results are shown in FIG. 34. As in Example 1, the reaching points
Lg and the acceleration points La are shown in Table 4 given
later.
[0210] FIG. 34 shows that the increase of take-up speed Vw changed
both the position of the reaching point Lg (reaching points Lg1x to
Lg3x) and the position of the acceleration point (acceleration
points La1x to La3x) toward the downstream side. However, the
position of every acceleration point La was on the downstream side
of one half of the distance to the position of the corresponding
reaching point Lg. That is, the comparative examples showed a
relation of acceleration point La>reaching point Lg/2
irrespective of the take-up speed Vw.
EXAMPLE 5 AND COMPARATIVE EXAMPLE 4
[0211] In Example 5 and Comparative Example 4, the apparatus shown
in FIG. 4 was used to produce polyester yarns each consisting of 36
filaments F with a filament fineness D of 135 dtex as described for
Example 1, except that the injection flow rate Ef, the injection
velocity Vs and the running air stream velocity Ve were changed as
shown in Table 5 given later. The yarn production conditions and
the properties of the obtained yarns in Example 5 and Comparative
Example 4 are shown in Table 5 given later.
[0212] In Example 5, the swing of the running 36 filaments F in the
positions upstream and downstream of the spinning tube 20 was
small, and a good spinning state was observed. It was confirmed
that the 36 filaments F maintained the disposal of filaments F as
achieved immediately after having been discharged from the
spinneret 12, in the range from the upstream side of the spinning
tube 20 to the outlet of the spinning tube 20, and that the
filaments F passed through the spinning tube 20 without being
converged (without contacting each other). On the other hand, in
comparative Example 4, probably because the drawing force of the
running air stream 40 acting on the filaments F was insufficient
due to the decrease of injection flow rate in the spinning tube 20,
the disposal of the filaments F was disturbed, and it was confirmed
that it happened especially in the upstream region of the spinning
tube 20 and that the filaments F ran unstably.
[0213] The results of yarn quality evaluation of the yarns Y wound
by the winding means 16 are shown in Table 5. The yarn properties
in Example 1 were 141% in elongation E, 2.4 g/dtex in strength T
and 0.95 in yarn irregularity U% at an injection velocity Vs of
6,000 m/min and a running air stream velocity Ve of 4,250 m/min. On
the contrary, those in Example 5 were 112% in elongation E, 3.2
g/dtex in strength T and 1.01 in yarn irregularity U% at an
injection velocity Vs of 4,900 m/min and a running air stream
velocity Ve of 3,240 m/min. Further, on the contrary, those in
Comparative Example 4 were 84% in elongation E, 3.5 g/dtex in
strength T and 1.34 in yarn irregularity U% at an injection
velocity Vs of 3,400 m/min and a running air stream velocity Ve of
1,980 m/min.
[0214] From these data, it can be seen that in the case where the
injection velocity Vs and the running air stream velocity Ve are
large, a yarn with a high elongation and small yarn irregularity
can be obtained.
[0215] It can also be seen that if the injection velocity Vs is
higher than the take-up speed Vw, the amount sucked into the
spinning tube 20 is stabilized, allowing a high quality yarn with a
high elongation to be obtained.
[0216] On the other hand, it can be seen that if the injection
velocity Vs is lower than the take-up speed, the amount sucked in
the spinning tube 20 decreases, destabilizing the running of the
filament F, hence causing yarn irregularity.
[0217] From these results and the results obtained in Examples 2
through 4, it can be seen that for producing a yarn with a high
elongation, keeping the running air stream velocity Ve at not less
than 60% of the take-up speed Vw is a desirable condition.
[0218] The filament speed Vf of the running filaments F at every
100 mm position from the spinneret was measured, and the results
are shown in FIG. 35. As in Example 1, the reaching points Lg and
the acceleration points La of Example 5 and Comparative Example 4
are shown in Table 6 given later.
[0219] In FIG. 35, in the case of Example 5, the position of the
acceleration point La (acceleration point La5) was on the upstream
side of one half of the distance to the position of the reaching
point Lg (reaching point Lg5), but in the case of Comparative
Example 4, the position of the acceleration point La (acceleration
point La4x) was on the downstream side of one half of the distance
to the position of the reaching point Lg (reaching point Lg4x). The
results show that unless an air stream having an adequate injection
velocity Vs and running air stream velocity Ve satisfying the
relation of the acceleration point La<reaching point Lg/2 is
given to the filaments F, a good quality yarn with a high
elongation and small yarn irregularity cannot be obtained. As can
be seen from Table 6, since the acceleration point La4x was
positioned outside the spinning tube range Le, the running air
stream velocity Ve did not effectively act on the filaments F in
Comparative Example 4.
EXAMPLES 6 and 7
[0220] As shown in Table 7 given later, in Example 6, a polyester
yarn consisting of 36 filaments F with a filament fineness D of 135
dtex was produced as described for Example 1, except that the
steady flow section of the spinning tube 20 was extended to change
the spinning tube length L2. On the other hand, in Example 7, a
polyester yarn consisting of 36 filaments F with a filament
fineness D of 135 dtex was produced as described for Example 6,
except that the injection flow rate Ef and the injection velocity
Vs were adjusted to ensure that the running air stream velocity Ve
became virtually equal to that of Example 1 (6,200 m/min). The yarn
production conditions and the properties of the obtained yarns in
these examples are shown together in Table 7 given later.
[0221] In each example, the swing of the running 36 filaments F in
the positions upstream and downstream of the spinning tube 20 was
small, and a good spinning state was observed. It was confirmed
that the 36 filaments F maintained the disposal of the filaments F
as achieved immediately after having been discharged from the
spinneret 12, in the range from the upstream side of the spinning
tube 20 to the outlet of the spinning tube 20, and that the
filaments F passed through the spinning tube 20 without being
converged (without contacting each other).
[0222] The results of yarn quality evaluation of the yarns Y wound
by the winding means 16 are shown in Table 7.
[0223] The yarn properties of Example 6 were 128% in elongation E,
2.7 g/dtex in strength T and 0.80 in yarn irregularity U% at a
running air stream velocity Ve of 3,680 m/min. Compared with
Example 1, the value of yarn irregularity U% was improved. However,
though the injection flow rate Ef was equivalent to that of Example
1, it is considered that the pressure resistance caused by the
longer steady flow section 21 lowered the running air stream
velocity Ve and also decreased the sucked flow 42a of the spinning
tube 20, to lower the total flow rate of the running air stream 40,
thus lowering the running air stream velocity Ve and lowering the
elongation of the obtained yarn.
[0224] The yarn properties of Example 7 were 140% in elongation E,
2.4 g/dtex in strength T and 0.82 in yarn irregularity U% at a
running air stream velocity Ve of 4,200 m/min. Compared with
Example 1, the elongation E was equivalent and the yarn
irregularity U% was better. These results suggest that a longer
spinning tube length L2 can inhibit the disturbance of the
filaments F running in the spinning tube 20, and that a running air
stream velocity Ve equivalent to or higher than the take-up speed
Vw is a factor capable of greatly improving the elongation of the
yarn. These effects can also be obtained by adjusting the length of
the bottom end section 24N of the spinning tube 20 of FIG. 9.
EXAMPLES 8, 9 and 10
[0225] The spinneret 12 used in Example 8 had numerous spinning
holes 13 arranged in two straight lines Z1 and Z2 as shown in FIG.
5B. The length Ey of the long sides 21L in the cross section of the
steady flow section 21 of the spinning tube 20 was changed to one
half of the Ey value of Example 1. Furthermore, the same yarn
production apparatus as used in Example 1 was used except that the
injection flow rate Ef and the injection velocity Vs were adjusted
to achieve a running air stream velocity Ve equivalent to that of
Example 1. Polyester yarns each consisting of 36 filaments F with a
filament fineness D of 135 dtex were produced.
[0226] In Examples 9 and 10, polyester yarns each consisting of 36
filaments F with a filament fineness D of 135 dtex were produced as
described for Example 8, except that the injection angle .theta. of
the injection holes 23a in the spinning tube 20 was changed as
shown in Table 8 given later. The yarn production conditions and
the properties of the obtained yarns in these examples are shown
together in Table 8 given later.
[0227] In each example, the swing of the running 36 filaments F in
the positions upstream and downstream of the spinning tube 20 was
small, and a good spinning state was observed. It was confirmed
that the 36 filaments F maintained the disposal of the filaments F
as achieved immediately after having been discharged from the
spinneret 12, in the range from the upstream side of the spinning
tube 20 to the outlet of the spinning tube 20, and that the
filaments F passed through the spinning tube 20 without being
converged (without contacting each other).
[0228] A yarn was produced under the same conditions as in Example
8, except that the spinneret used had the spinning holes 13
arranged in straight lines Z1 and Z2 to overlap each other on the
projection drawing of the spinneret, in an attempt to evaluate the
yarn similarly. However, in this case, a phenomenon occurred, in
which the filaments F entering the spinning tube 20 fused each
other in the upstream region of the spinning tube 20. Since
filament breaking and fluffing occurred in the yarn, the yarn was
not taken up for evaluation.
[0229] The results of yarn quality evaluation of the yarns Y wound
by the winding means 16 are shown in Table 8. The yarn properties
of Example 8 were 140% in elongation E, 2.4 g/dtex in strength T
and 0.98 in yarn irregularity U%. It was found that a yarn with the
same quality as that of Example 1 was obtained. It was confirmed
that even in the case where the spinneret 12 has spinning holes 13
arranged in two rows, if the spinning holes 13 are positioned to
avoid overlapping in the direction perpendicular to the respective
straight lines Z1 and Z2, the intended yarn could be produced
without any problem.
[0230] If a spinneret having the spinnerets 13 arranged in plural
rows is employed, the length Ey of the long sides of the filament
passage 25 of the spinning tube 20 can be shortened. In the case
where the spinning holes are arranged in two rows, the length Ey
becomes about one half of the length needed when they are arranged
in one row, if the number of filaments F and the filament fineness
D are identical. In this case, the injection flow rate Ef can be
decreased to reduce the production cost needed for compressed air
consumption.
[0231] In Examples 9 and 10 where the injection angle .theta. was
changed, the running air stream velocity Ve increased when the
injection angle .theta. was made sharper, compared with that in
Example 8. It is considered that if the injection angle .theta. is
smaller, the sucked flow 42a entering from the inlet of the
filament passage 25 of the spinning tube 20 increases to increase
the flow rate of the running air stream 40.
[0232] The properties of the wound yarns were evaluated. Those of
Example 9 were 143% in elongation E, 2.4 g/dtex in strength T and
0.91 in yarn irregularity U% at a running air stream velocity Ve of
4,780 m/min. Those of Example 10 were 145% in elongation E, 2.3
g/dtex in strength T and 0.88 in yarn irregularity U% at a running
air stream velocity Ve of 5,230 m/min. That is, it was confirmed
that if the injection angle .theta. is smaller, a good quality yarn
with an elongation equivalent or higher than that of Example 9
could be obtained.
EXAMPLE 11
[0233] A polyester yarn consisting of 36 filaments F with a
filament fineness D of 135 dtex was produced as described for
Example 1 under the conditions shown in Table 9 given later, except
that an apparatus as shown in FIG. 12 was used, in which flow
regulation sections 31 having air regulation plates were installed
upstream of the spinning tube 20. The air regulating boards were
honeycomb grates installed on both sides of the filaments F at a
position immediately above the air inlet section 22 of the spinning
tube 20. The size of each flow regulation section 31 was 60 mm in
length Lc and 10 mm in thickness Lt. The yarn production conditions
and the properties of the obtained yarn of Example 11 are shown
together in Table 9 given later.
[0234] In Example 11, the swing of the running 36 filaments F in
the positions upstream and downstream of the spinning tube 20 was
small, and a good spinning state was observed. It was confirmed
that the 36 filaments F maintained the disposal of the filaments F
as achieved immediately after having been discharged from the
spinneret 12, in the range from the upstream side of the spinning
tube 20 to the outlet of the spinning tube 20, and that the
filaments F passed through the spinning tube 20 without being
converged (without contacting each other).
[0235] The yarn properties of the wound yarn Y were evaluated and
found to be 143% in elongation E, 2.4 g/dtex in strength T and 0.85
in yarn irregularity U%. Compared with Example 1, since the air
regulation plates regulated the sucked flow 42a, it could be
visually confirmed that the swing of the filaments F in the
position upstream of the spinning tube 20 was smaller than that in
Example 1, and that because of it, the yarn irregularity could be
further improved.
EXAMPLES 12 and 13
[0236] Polyester yarns each consisting of 36 filaments F with a
filament fineness D of 135 dtex were produced under the conditions
shown in Table 10 given later, as described for Example 1, except
that, as shown in FIG. 15, a block-shaped temperature regulation
pipe 37 for controlling the temperature of the filaments F was
installed upstream of the spinning tube 20, to adjust the
temperature TH of the temperature regulation section in the
temperature regulation passage 35a at 250.degree. C. The cross
sectional form of the temperature regulation passage 35a of the
temperature regulation pipe 37 was rectangular, and the length LH
of the temperature regulation section as the length of the
temperature regulation pipe 37 in the running direction of the
filaments F was 60 mm. Ceramic heaters were installed as heating
members 36 in the long side direction 37a of the rectangular
temperature regulation passage 35a. The yarn production conditions
and the properties of the obtained yarns in these examples are
shown together in Table 10 given later.
[0237] In each example, the swing of the running 36 filaments F in
the positions upstream and downstream of the spinning tube 20 was
small, and a good spinning state was observed. It was confirmed
that the 36 filaments F maintained the disposal of the filaments as
achieved immediately after having been discharged from the
spinneret 12, in the range from the upstream side of the spinning
tube 20 to the outlet of the spinning tube 20, and that the
filaments F passed through the spinning tube 20 without being
converged (without contacting each other).
[0238] The yarn properties of the wound yarns Y were evaluated.
Those of Example 12 with the running air stream velocity Ve set at
4,250 m/min were 153% in elongation E, 2.2 g/dtex in strength T and
0.95 in yarn irregularity U%. Compared with Example 1, the winding
speed was equal, but a yarn having a higher elongation could be
obtained.
[0239] Those of Example 13 with the running air stream velocity set
at 3,200 m/min were 140% in elongation E, 2.4 g/dtex in strength T
and 0.92 in yarn irregularity U%. Even if the injection flow rate
Ef was lowered, a yarn with the same quality as that of Example 1
could be obtained since the temperature regulation means 35 was
used.
[0240] As in Example 12, the temperature Ti of the filaments F in
the position upstream of the spinning tube 20 was measured and
found to be 227.degree. C. The temperature Ti in Example 1 was
215.degree. C. as shown in Table 2, and this value was lower than
those of Examples 12 and 13. This means that if the temperature of
the filaments F before they enter the spinning tube 20 is kept at a
high temperature, an equivalent elongation E can be obtained even
if the running air stream velocity Ve in the spinning tube 20 is
lowered. Therefore, since the injection flow rate Ef can be
decreased, the yarn production cost can be reduced.
COMPARATIVE EXAMPLE 5
[0241] The apparatus used in Comparative Example 5 was the same as
the apparatus shown in FIG. 1 used in Comparative Example 1, except
that a cylindrical air stream forming section 70 consisting of a
cylindrical cooling means 55, a funnel-shaped acceleration section
72 and a tube 73 shown in FIG. 3 was installed instead of the
cooling means 3, in which the cooling air 55a was sent to the tube
73 for generating a parallel stream 73a in parallel to the running
direction of the filaments F in the tube 73. The cylindrical air
stream forming section 70 had the following dimensions: the
distance LD from the spinneret 1 to the cylindrical cooling means
55 (spinneret depth) was 25 mm; the length LP of the cylindrical
cooling means 55 in the vertical direction (cooling cylinder
length) was 300 mm; the angle of the funnel-shaped acceleration
section 74 (acceleration taper angle) was 60.degree.; the length LR
of the funnel-shaped acceleration section in the vertical direction
(acceleration length) was 55 mm; the length LN of the tube 73 (tube
length) was 450 mm; and the tube diameter d1 was 25 mm. The
apparatus was the same as that of Comparative Example 1, except the
cylindrical air stream forming section 70.
[0242] This apparatus was used to produce a polyester yarn
consisting of 36 filaments F with a filament fineness D of 135 dtex
under the conditions shown in Table 11 given later. The cooling air
was supplied to the cylindrical cooling means 55 to achieve a
cooling air velocity Vc of 30 m/min, and in this case, it was
confirmed that the air velocity Vt in the tube 73 was 2,200 m/min.
The yarn production conditions and the properties of the obtained
yarn in Comparative Example 5 are shown together in Table 11 given
later.
[0243] The yarn properties of the wound yarn of Comparative Example
5 were evaluated and found to be 108% in elongation E, 2.9 g/dtex
in strength T and 1.22 in yarn irregularity U%.
[0244] The yarn produced in Comparative Example 5 was larger in the
value of yarn irregularity U% than in the examples in conformity
with the invention, though it could be improved in the value of
elongation E. The yarn production apparatus used in Comparative
Example 5 was found to be likely to cause yarn irregularity.
[0245] Since the yarn was whirled and the filaments F crossed each
other at the outlet of the tube 73, it was confirmed that the
filaments F (yarn Y) were disturbed and unstable in running. The
reason is that the passage through which the filaments F ran had a
cylindrical form. This phenomenon does not occur in the yarn
production method and apparatus of the invention, in which the
spinning holes of the spinneret are arranged along a straight line
and in which the cross sectional form of the filament passage of
the spinning tube is rectangular. The cooling air velocity Vc was
raised to raise the air velocity Vt in the tube, but the higher
cooling air velocity Vc caused the discharged numerous filaments F
composed of a polymer to be converged at the center and fused each
other, not being able to be taken up as a yarn Y.
[0246] A second group of Examples and Comparative Examples:
[0247] The apparatus shown in FIG. 19 was used to produce a
polyester yarn for evaluation. The yarn production conditions are
shown in Table 12 given later. The yarn production state was
evaluated for 36 hours after start of yarn production. During this
period, the running state of the filaments F was observed
adequately, and the produced yarn was sampled every 12 hours, for
evaluating the yarn properties. The production of the yarn was
stopped 36 hours after start of production. When the production of
the yarn was stopped, the state of the filament passage 25 in the
spinning tube 20 was observed.
[0248] The spinning tube 20 used in Example 14 is shown in FIGS. 6
and 7. The cross sectional form of the filament passage 25 was
rectangular. The air inlet section 22 had a widened portion 22a.
The air discharge section 24 had a widened portion 24a. The length
Ex of the short sides of the rectangle as the cross sectional form
of the filament passage 25 in the steady flow section 21 was 2 mm,
and the length Ey of the long sides was 100 mm. The injection holes
23a open on the wall faces of the filament passage 25 were formed
as slits. The slits were open over the entire length of the long
sides 21L of the rectangle as the cross sectional form of the
filament passage 25. The slit width Ei (see FIG. 9) of the slits
was 0.4 mm.
[0249] For the suction gas velocity SV occurring at each gas
suction port 62 of the gas suction device 60, the correlation
between the values indicated by the pressure gauge 67 and the
achieved gas velocities was measured beforehand, to obtain the
value of the suction gas velocity SV. The numerous filaments F were
guided to run downward at the center between the gas suction ports
62 installed on both sides of the filaments. The distance between
each gas suction port 62 and the filaments F (suction distance PL)
was set at 1/2 of the distance between both the gas suction ports
62.
[0250] For the suction spaces 80 provided between the gas suction
device 60 and the spinning tube 20 as shown in FIG. 23, honeycomb
grate members (thickness 15 mm, grate pitch 3 mm) were used and
installed on both sides of the numerous filaments F in parallel
with them. Like the gas suction device 60, side plates 68 were used
to close the faces in the short side direction against the outside
(see FIG. 22).
[0251] In FIG. 19, SL (mm) indicates the distance from the bottom
face of the spinneret 12 to the top face of the gas suction device
60, and defines the space below the nozzle. BL (mm) indicates the
length of the gas suction device 60 in the vertical direction, and
defines the suction region. AL (mm) indicates the length of the
suction spaces 80 (see FIG. 23) from the bottom face of the gas
suction device 60 to the top face of the spinning tube 20 in the
vertical direction, and defines the ventilation distance.
[0252] In FIG. 18, L1 (mm) indicates the distance from the bottom
face of the spinneret 12 to the top face of the spinning tube 20,
and defines the spinning tube position. L2 (mm) indicates the
overall length of the spinning tube 20 and defines the spinning
tube length. L3 (mm) indicates the distance from the bottom face of
the spinneret 12 to the oiling means 17 and defines the oiling
position. L4 (mm) indicates the distance from the bottom face of
the spinneret to the first godet roller 14, and defines the take-up
position. Vw (m/min) indicates the yarn Y take-up speed by the
first godet roller 14, and defines the take-up speed. In FIG. 6, Es
(mm) indicates the distance from the top face of the spinning tube
20 to the injection holes 23a of the air injection section 23 (the
center of the open faces of the injection holes 23a in the vertical
direction on the wall faces of the filament passage 25), and
defines the slit position.
[0253] For the spinneret 12, the distance between the respectively
adjacent spinning holes 13 is called the spinning hole pitch P
(mm), and the hole diameter of the spinning holes 13 on the bottom
face of the spinneret 12 is called the spinning hole diameter d
(mm). The center distance between the two spinning holes most apart
from each other among the plural spinning holes 13 is called the
distance dw (mm) between the outermost spinning holes.
EXAMPLE 14
[0254] The apparatus of FIG. 19 was used to produce a polyester
yarn (PET yarn) consisting of 36 filaments F with a filament
fineness D of 135 dtex under the conditions shown in Table 12 given
later at a speed of 5,000 m/min. The spinneret 12 used had all the
numerous spinning holes arranged in a straight line Z as shown in
FIG. 5A. The spinning hole pitch P was 2.5 mm, the spinning hole
diameter d was 0.3 mm, and the distance dw between the outermost
spinning holes was 87.5 mm.
EXAMPLE 15 AND COMPARATIVE EXAMPLE 6
[0255] Example 15 and Comparative Example 6 were carried out under
the same conditions, except that the gas suction velocity SV was
changed. The yarn properties of the yarns sampled after lapse of
predetermined times are shown in Table 13. The evaluated yarn
properties were strength T, elongation E, yarn irregularity U% and
fluff K. Table 13 also shows the results of the inner face of the
filament passage 25 of the spinning tube 20 observed 36 hours after
start of yarn production.
[0256] To measure the strength T and elongation E, a test yarn with
a length of 50 mm cut from a produced yarn (multifilament) was
stretched at a tensile speed of 400 mm/min till it was broken using
a general tensile tester. To measure the yarn irregularity U%,
Uster Tester 1 Model C produced by Zellweger Co., Ltd. was used,
and a yarn was supplied at a speed of 100 m/min for measuring in
the normal mode. To measure the fluff K, a fly counter produced by
Toray Engineering Co., Ltd. was used to count the number of fluffy
pieces in a measuring length of 12,000 m at a speed of 400
m/min.
[0257] In each of Example 14 and 15, the swing of filaments F was
small throughout the yarn production period, and a good spinning
state was maintained. It was confirmed that the numerous filaments
F maintained the disposal of the filaments as achieved immediately
after having been discharged from the spinneret 12, in the range
from the spinneret 12 to the outlet of the spinning tube 20, and
that the filaments passed through the spinning tube 20 without
being converged (without contacting each other). The yarn
properties of the wound yarns were evaluated. As shown in Table 13,
the yarn irregularity U% values in Example 14 were 0.85 after lapse
of 12 hours, 0.88 after lapse of 24 hours and 0.84 after lapse of
36 hours, and those in Example 15 were 0.83 after lapse of 12
hours, 0.80 after lapse of 24 hours and 0.82 after lapse of 36
hours. On the whole, the fluff of yarns was not observed. Thirty
six hours after start of yarn production, the yarn production was
stopped, and the spinning tube 20 was dismantled, to inspect the
deposition of the volatile matter onto the filament passage 25. The
deposition of the volatile substance was substantially not
observed, and the filament passage was little contaminated and kept
in a good state.
[0258] On the other hand, in Comparative Example 6 in which the gas
suction device 60 was not used for suction, the filaments F
entering the spinning tube 20 began to swing after lapse of about
18 hours, and it was observed that the swing became large after
lapse of about 30 hours. The yarn irregularity U% of the obtained
yarn became worse with the lapse of time. Though no fluff existed
in the yarn sampled immediately after start of yarn production, the
fluff of the sampled yarn increased with the lapse of time. After
lapse of 36 hours, the filament passage 25 of the spinning tube 20
was observed, and it was found that a large amount of a deposit
like white powder had been deposited, and that the air injection
section 23 had been partially clogged. The deposit was examined by
means of chromatography, and it was confirmed that the main
component was hydroxyethyl terephthalate sublimed from the
polyester.
[0259] The examples used polyethylene terephthalate yarns (PET
yarns) only since they are typical polyester yarns, but in the
invention, the polymer used is not especially limited. For example,
also in the production of yarns of polyamide, polypropylene and
aliphatic polyesters (polylactic acid, etc.), similar effects can
be obtained. The yarn production method and apparatus can be
especially preferably applied to a polylactic acid yarn, since it
generates a large amount of a volatile matter. TABLE-US-00001 TABLE
1 Item Unit Example 1 Example 2 Example 3 Example 4 Vw: Take-up
speed m/min 5,000 '' '' '' D: Fineness dtex 135 '' '' '' F: Number
of filaments Number 36 '' '' '' d: Spinning hole diameter mm 0.3 ''
'' '' P: Spinning hole pitch mm 2.5 '' '' '' L2: Spinning tube
length mm 300 '' '' '' Ey: Length of long sides of passage mm 100
'' '' '' Ex: Length of short sides of passage mm 2 '' '' ''
.theta.: Injection angle degrees 15 '' '' '' Ei: Injection slit
width mm 0.4 '' '' '' Es: Injection slit position mm 50 '' '' ''
L1: Spinning tube position mm 100 200 300 400 L3: Oiling means
position mm 1,500 '' '' '' L4: Take-up position mm 3,200 '' '' ''
Ef: Injection flow rate m.sup.3/min 0.5 '' '' '' Vs: Injection
velocity m/min 6,000 '' '' '' Ve: Running air stream velocity m/min
4,250 '' '' '' T: Strength g/dtex 2.4 2.6 2.8 3.0 E: Elongation %
141 128 104 86 U %: Yarn irregularity U value 0.95 0.93 1.00
1.13
[0260] TABLE-US-00002 TABLE 2 Exam- Exam- Exam- Exam- Item Unit ple
1 ple 2 ple 3 ple 4 Lg: Take-up speed mm 900 900 1,000 1,100
reaching position La: Maximum mm 250 350 450 550 acceleration
position Ti: Filament temperature .degree. C. 215 203 184 158 VL:
Filament speed at m/min 1,800 2,200 2,400 2,500 maximum
acceleration position Le: Spinning tube range L1: mm 100 200 300
400 L1 + L2 mm 400 500 600 700
[0261] TABLE-US-00003 TABLE 3 Com- Com- Com- parative parative
parative Item Unit Example 1 Example 2 Example 3 Vw: Take-up speed
m/min 5,000 4,000 3,500 D: Fineness dtex 135 '' '' F: Number of
filaments Number 36 '' '' d: Spinning hole diameter mm 0.3 '' ''
L22: Cooling length mm 1,000 '' '' EY: Cooling section width mm 200
'' '' L11: Cooling means mm 80 '' '' position L33: Oiling means
position mm 1,500 '' '' L44: Take-up position mm 3,200 '' '' Vcl:
Cooling air velocity m/min 30 '' '' T: Strength g/dtex 3.1 2.9 2.7
E: Elongation % 65 98 119 U %: Yarn irregularity U value 1.24 1.13
1.05
[0262] TABLE-US-00004 TABLE 4 Comparative Comparative Comparative
Item Unit Example 1 Example 2 Example 3 Lg: Take-up speed mm 700
900 800 reaching position La: Maximum mm 650 550 450 acceleration
position
[0263] TABLE-US-00005 TABLE 5 Com- parative Item Unit Example 1
Example 5 Example 4 Vw: Take-up speed m/min 5,000 '' '' D: Fineness
dtex 135 '' '' F: Number of filaments Number 36 '' '' d: Spinning
hole diameter mm 0.3 '' '' P: Spinning hole pitch mm 2.5 '' '' L2:
Spinning tube length mm 300 '' '' Ey: Length of long sides mm 100
'' '' of passage Ex: Length of short sides mm 2 '' '' of passage
.theta.: Injection angle degrees 15 '' '' Ei: Injection slit width
mm 0.4 '' '' Es: Injection slit position mm 50 '' '' L1: Spinning
tube position mm 100 '' '' L3: Oiling means position mm 1,500 '' ''
L4: Take-up position mm 3,200 '' '' Ef: Injection flow rate
m.sup.3/min 0.5 0.4 0.3 Vs: Injection velocity m/min 6,000 4,900
3,400 Ve: Running air stream m/min 4,250 3,240 1,980 velocity T:
Strength g/dtex 2.4 3.2 3.5 E: Elongation % 141 112 84 U %: Yarn
irregularity U value 0.95 1.01 1.34
[0264] TABLE-US-00006 TABLE 6 Comparative Item Unit Example 1
Example 5 Example 4 Lg: Take-up speed mm 900 1,000 1,000 reaching
position La: Maximum mm 250 350 650 acceleration position VL:
Filament speed m/min 1,800 2,300 3,500 at maximum acceleration
position Le: Spinning tube range L1: mm 100 100 100 L1 + L2 mm 400
400 400
[0265] TABLE-US-00007 TABLE 7 Item Unit Example 1 Example 6 Example
7 Vw: Take-up speed m/min 5,000 '' '' D: Fineness dtex 135 '' '' F:
Number of filaments Number 36 '' '' d: Spinning hole diameter mm
0.3 '' '' P: Spinning hole pitch mm 2.5 '' '' L2: Spinning tube
length mm 300 900 900 Ey: Length of long sides mm 100 '' '' of
passage Ex: Length of short sides mm 2 '' '' of passage .theta.:
Injection angle degrees 15 '' '' Ei: Injection slit width mm 0.4 ''
'' Es: Injection slit position mm 50 '' '' L1: Spinning tube
position mm 100 '' '' L3: Oiling means position mm 1,500 '' '' L4:
Take-up position mm 3,200 '' '' Ef: Injection flow rate m.sup.3/min
0.5 '' 0.6 Vs: Injection velocity m/min 6,000 '' 6,600 Ve: Running
air stream m/min 4,250 3,680 4,200 velocity T: Strength g/dtex 2.4
2.7 2.4 E: Elongation % 141 128 140 U %: Yarn irregularity U value
0.95 0.80 0.82
[0266] TABLE-US-00008 TABLE 8 Example Item Unit Example 1 Example 8
Example 9 10 Vw: Take-up speed m/min 5,000 '' '' '' D: Fineness
dtex 135 '' '' '' F: Number of filaments Number 36 '' '' '' d:
Spinning hole diameter mm 0.3 '' '' '' P: Spinning hole pitch mm
2.5 '' '' '' W: Spinning hole row pitch mm -- 2.5 2.5 2.5 L2:
Spinning tube length mm 300 '' '' '' Ey: Length of long sides of
passage mm 100 50 50 50 Ex: Length of short sides of passage mm 2
'' '' '' .theta.: Injection angle degrees 15 '' 10 5 Ei: Injection
slit width mm 0.4 '' '' '' Es: Injection slit position mm 50 '' ''
'' L1: Spinning tube position mm 100 '' '' '' L3: Oiling means
position mm 1,500 '' '' '' L4: Take-up position mm 3,200 '' '' ''
Ef: Injection flow rate m.sup.3/min 0.5 0.25 0.25 0.25 Vs:
Injection velocity m/min 6,000 5,900 5,900 5,900 Ve: Running air
stream velocity m/min 4,250 4,190 4,780 5,230 T: Strength g/dtex
2.4 2.4 2.4 2.3 E: Elongation % 141 140 143 145 U %: Yarn
irregularity U value 0.95 0.98 0.91 0.88
[0267] TABLE-US-00009 TABLE 9 Item Unit Example 1 Example 11 Vw:
Take-up speed m/min 5,000 '' D: Fineness dtex 135 '' F: Number of
filaments Number 36 '' d: Spinning hole diameter mm 0.3 '' P:
Spinning hole pitch mm 2.5 '' Lc: Air regulation plate length mm --
60 Lt: Air regulation plate thickness mm -- 10 L2: Spinning tube
length mm 300 '' Ey: Length of long sides mm 100 '' of passage Ex:
Length of short sides mm 2 '' of passage .theta.: Injection angle
degrees 15 '' Ei: Injection slit width mm 0.4 '' Es: Injection slit
position mm 50 '' L1: Spinning tube position mm 100 '' L3: Oiling
means position mm 1,500 '' L4: Take-up position mm 3,200 '' Ef:
Injection flow rate m.sup.3/min 0.5 '' Vs: Injection velocity m/min
6,000 '' Ve: Running air stream m/min 4,250 '' velocity T: Strength
g/dtex 2.4 2.4 E: Elongation % 141 143 U %: Yarn irregularity U
value 0.95 0.85
[0268] TABLE-US-00010 TABLE 10 Example Example Item Unit Example 1
12 13 Vw: Take-up speed m/min 5,000 '' '' D: Fineness dtex 135 ''
'' F: Number of filaments Number 36 '' '' d: Spinning hole diameter
mm 0.3 '' '' P: Spinning hole pitch mm 2.5 '' '' LH: Temperature mm
-- 60 60 regulation section length TH: Temperature .degree. C. --
250 250 regulation section temperature L2: Spinning tube length mm
300 '' '' Ey: Length of long sides mm 100 '' '' of passage Ex:
Length of short sides mm 2 '' '' of passage .theta.: Injection
angle degrees 15 '' '' Ei: Injection slit width mm 0.4 '' '' Es:
Injection slit position mm 50 '' '' L1: Spinning tube position mm
100 '' '' L3: Oiling means position mm 1,500 '' '' L4: Take-up
position mm 3,200 '' '' Ef: Injection flow rate m.sup.3/min 0.5 ''
0.4 Vs: Injection velocity m/min 6,000 '' 4,500 Ve: Running air
stream m/min 4,250 '' 3,200 velocity T: Strength g/dtex 2.4 2.2 2.4
E: Elongation % 141 153 140 U %: Yarn irregularity U value 0.95
0.95 0.92
[0269] TABLE-US-00011 TABLE 11 Item Unit Comparative Example 5 Vw:
Take-up speed m/min 5,000 D: Fineness dtex 135 F: Number of
filaments Number 36 d: Spinning hole diameter mm 0.3 LP: Cooling
tube length mm 300 d1: Tube diameter mm 25 .theta.1: Acceleration
taper angle degrees 60 Lb: Tube length mm 450 LR: Acceleration
length mm 55 L3: Oiling means position mm 1,500 L4: Take-up
position mm 3,200 Vc: Cooling air velocity m/min 30 Vt: Tube air
velocity m/min 2,200 T: Strength g/dtex 2.9 E: Elongation % 108 U
%: Yarn irregularity U value 1.22
[0270] TABLE-US-00012 TABLE 12 Com- Example Example parative Item
Unit 14 15 Example 6 Vw: Take-up speed m/min 5,000 '' '' D:
Fineness dtex 135 '' '' F: Number of filaments Number 36 '' '' d:
Spinning hole diameter mm 0.3 '' '' P: Spinning hole pitch mm 2.5
'' '' TP: Nozzle temperature .degree. C. 285 '' '' SL: Space below
nozzle mm 5 '' '' BL: Suction region mm 45 '' '' AL: Ventilation
distance mm 50 '' '' Sv: Suction gas velocity m/min 10 30 0 PL:
Suction distance mm 10 '' '' L2: Spinning tube length mm 300 '' ''
Ey: Length of long sides mm 100 '' '' of passage Ex: Length of
short sides mm 2 '' '' of passage .theta.: Injection angle degrees
15 '' '' Ei: Injection slit width mm 0.4 '' '' Es: Injection slit
position mm 50 '' '' L1: Spinning tube position mm 100 '' '' L3:
Oiling means position mm 1,500 '' '' L4: Take-up position mm 3,200
'' '' Vs: Injection velocity m/min 6,000 '' '' Ve: Running air
stream m/min 4,250 '' '' velocity
[0271] TABLE-US-00013 TABLE 13 Example Example Comparative Item
Unit 14 15 Example 6 After lapse T: Strength g/dtex 2.5 2.6 2.4 of
12 hours E: Elongation % 135 136 130 U %: Yarn irregularity U value
0.85 0.83 1.00 K: Number of fluff pieces Number/12 km 0 0 0 After
lapse T: Strength g/dtex 2.5 2.6 2.4 of 14 hours E: Elongation %
135 136 130 U %: Yarn irregularity U value 0.88 0.80 1.10 K: Number
of fluff pieces Number/12 km 0 0 18 After lapse T: Strength g/dtex
2.5 2.6 2.4 of 36 hours E: Elongation % 135 136 130 U %: Yarn
irregularity U value 0.84 0.82 1.14 K: Number of fluff pieces
Number/12 km 0 0 67 Result of Little Little Much confirmation of
contamination after lapse of 36 hours
INDUSTRIAL APPLICABILITY
[0272] The yarn production method and apparatus of the invention
use a spinneret having numerous spinning holes arranged at a
desired pitch as a row or plural rows in a straight line(s), a
spinning tube (ejector) having a filament passage through which a
row(s) of numerous filaments composed of a polymer discharged from
the spinning holes and running downward from the spinneret pass
(es), an oiling means for applying an oiling agent to the numerous
filaments coming out of the spinning tube, a take-up means for
taking up the oiled numerous filaments, and a yarn winding means
for winding the numerous filaments coming from the take-up means,
wherein in the filament passage of the spinning tube, air is
injected obliquely downward toward the numerous filaments disposed
in the row direction of the spinning holes and entering the
filament passage, from both sides of the disposal of the numerous
filaments, to dispose the numerous filaments in one row without
allowing them to overlap each other, and the air stream formed as a
confluence of the air streams injected obliquely downward from both
sides and running downward in the filament passage acts on the
disposed numerous filaments running downward in the filament
passage for drawing them, to make them thinner, before the polymer
constituting the filaments is solidified; in this yarn production
process, since the velocity of the air stream running downward in
the filament passage is not less than 60% of the take-up speed of
the numerous filaments taken up by the take-up means or since the
gas generated from the numerous filaments is sucked and discharged
outside in the range between the spinneret and the spinning tube, a
yarn with a high elongation can be wound by a yarn winding means
even if the yarn take-up speed of the take-up means is high. The
obtained yarn is small in the irregularity between filaments. Even
in the case where the width of the filament passage in the
direction perpendicular to the direction in which the numerous
filaments are disposed side by side is small, since the gas
generated from the numerous filaments in the range between the
spinneret and the spinning tube is sucked and discharged outside,
it can be prevented that the volatile substance of the filaments
contaminates the filament passage having a narrow width. So, a
stable yarn can be continuously produced without suspension of yarn
production.
* * * * *