U.S. patent application number 13/320239 was filed with the patent office on 2012-05-10 for method and device for melt spinning and cooling a plurality of monofilaments.
This patent application is currently assigned to OERLIKON TEXTILE GMBH & CO.KG. Invention is credited to Kenneth Schindler, Bert Wollner.
Application Number | 20120112381 13/320239 |
Document ID | / |
Family ID | 42312823 |
Filed Date | 2012-05-10 |
United States Patent
Application |
20120112381 |
Kind Code |
A1 |
Wollner; Bert ; et
al. |
May 10, 2012 |
METHOD AND DEVICE FOR MELT SPINNING AND COOLING A PLURALITY OF
MONOFILAMENTS
Abstract
The invention relates to a method and a device for melt spinning
and cooling a plurality of monofilaments which are extruded through
a plurality of openings of a spinneret and guided into a cooling
bath. The removal process consists of redirecting the monofilaments
within the cooling bath. According to the invention, in order to
prevent adhesion and an oblique pull-off, the monofilaments are
divided into multiple filament groups after extrusion, said groups
consisting of multiple monofilaments, and the filament groups are
individually redirected independently of each other within the
cooling bath into multiple redirecting positions by separate
redirecting sheaves.
Inventors: |
Wollner; Bert;
(Hohenstein-Ernstthal, DE) ; Schindler; Kenneth;
(Chemnitz, DE) |
Assignee: |
OERLIKON TEXTILE GMBH &
CO.KG
Remscheid
DE
|
Family ID: |
42312823 |
Appl. No.: |
13/320239 |
Filed: |
May 3, 2010 |
PCT Filed: |
May 3, 2010 |
PCT NO: |
PCT/EP10/55966 |
371 Date: |
January 23, 2012 |
Current U.S.
Class: |
264/178F ;
425/71 |
Current CPC
Class: |
D01D 5/0885
20130101 |
Class at
Publication: |
264/178.F ;
425/71 |
International
Class: |
D01D 5/088 20060101
D01D005/088 |
Foreign Application Data
Date |
Code |
Application Number |
May 13, 2009 |
DE |
10 2009 021 117.9 |
Claims
1-14. (canceled)
15. A method for melt spinning and cooling a plurality of
monofilaments, said method comprising: extruding the monofilaments
through a plurality of nozzle openings of a spinneret and guiding
the monofilaments into a cooling bath, in which the monofilaments
when they are pulled off the cooling bath are guided by deflection
means, wherein upon extrusion, the monofilaments are divided into
several filament groups of several monofilaments and wherein the
filament groups, independently of each other, are separately
redirected inside the cooling bath into several deflection
positions.
16. The method according to claim 15, wherein the filament groups
are each redirected in the deflection positions by individually
freely rotating deflection rolls.
17. The method according to claim 15, wherein upon extrusion, the
monofilaments inside their filament group are guided between the
spinning nozzle and the deflection positions with a maximal
deflection <5.degree..
18. The method according to claim 15, wherein the monofilaments are
extruded next to each other in an annular arrangement and are
divided into filament groups.
19. The method according to claim 15, wherein a cooling path of the
monofilaments inside the cooling bath is controlled by adjusting
the deflection positions of the filament groups.
20. The method according to claim 15, wherein upon cooling and
redirection, the monofilaments of the filament groups are jointly
guided as an assemblage, with the deflection positions inside the
cooling bath partially being held at different heights.
21. A device for melt spinning and cooling a plurality of
monofilaments with a spinneret, said device comprising: a multitude
of nozzle openings for extruding the monofilaments and arranged
above a cooling bath; several deflection means for redirecting the
monofilaments inside the cooling bath; and a pull-out means for
pulling the monofilaments out of the cooling bath, wherein the
deflection means are arranged underneath the spinneret such that,
upon extrusion, the monofilaments can be divided into several
filament groups of several monofilaments and wherein the filament
groups can individually be redirected independent from each other
inside the cooling bath at several deflection positions by the
deflection means.
22. The device according to claim 21, wherein the deflection means
are formed by several freely rotating deflection rolls which are
held individually in the deflection positions.
23. The device according to claim 21, wherein the positions or the
number of deflection means underneath the spinneret are selected
such that, upon extrusion, the monofilaments inside their filament
group can be guided between the spinneret and the deflection means
with a maximum deflection of <5.degree..
24. The device according to claim 21, wherein the nozzle openings
of the spinneret are embodied in an annular arrangement at the
bottom of the spinneret and wherein the deflection means are
positioned underneath the spinneret in an arrangement congruent to
form the filament groups.
25. The device according to claim 21, wherein the deflection means
are arranged at a distance in reference to a plate-shaped fastener,
the fastener being embodied mobile in order to adjust the
deflection positions.
26. The device according to claim 25, wherein the fastener is
connected via a pivotal axis to a carrier, by which an angular
incline can be adjusted at the fastener.
27. The device according to claim 25, wherein the fastener is
connected to a carrier in a height-adjustable fashion.
28. The device according to claim 21, wherein a comb-shaped guide
bar is arranged downstream in reference to the deflection means
outside the cooling bath, by which the monofilaments of the
filament groups can be guided as an assemblage of separated
monofilaments.
Description
[0001] The invention relates to a method for melt spinning and
cooling a plurality of monofilaments according to the preamble of
claim 1 as well as a device for melt spinning and cooling a
plurality of monofilaments according to the preamble of claim
7.
[0002] In the production of monofilaments from a thermoplastic
material it is common that for cooling purposes after extrusion the
monofilaments are immediately guided into a cooling bath filled
with water. This way, even in larger filament titers, short cooling
paths can be realized in the melt spinning process. Inside the
cooling bath, it is required to guide the monofilaments out of the
cooling bath for further processing, particularly for stretching.
For this purpose the monofilaments are redirected by at least one
deflection means for pull-out of the cooling bath. Here, it is
required that the monofilaments extruded through the jet openings
at the bottom of the spinneret are jointly guided to a deflection
means, for example, a deflection rod or a deflection roll. For this
purpose, all extruded monofilaments are guided to a deflection
position of the deflection means, at which they are jointly
tangentially guided next to each other.
[0003] Such a method and a respective device are known, for example
from DE 196 00 090 A1.
[0004] From the known method and the known device, several
deflection means are arranged successively in the traveling
direction of the filaments in the cooling path, in order to yield a
redirection of the monofilaments as gently as possible. Here, after
extrusion the monofilaments are all jointly guided to a first
deflection position of the first deflection means. Depending on the
distance between the spinneret and the deflection means here,
greater redirections of the monofilaments that are extruded at the
edge section of the spinneret are unavoidable. Such an oblique
distortion at the monofilaments causes different tensions, which in
turn result in different crystallization of the fibrous materials
and in quality differences in the monofilaments. Additionally, in a
large number of monofilaments the risk of contacting is increased
when the monofilaments are joined at the deflection position, so
that adhesions of individual monofilaments are unavoidable. Such
problems particularly occur when melt spinning monofilaments are
exclusively cooled by a cooling liquid in a cooling bath. In such
methods and devices particularly, very short distances must be
bridged between the spinneret and the deflection means inside the
cooling bath.
[0005] Therefore the objective of the invention is to provide a
method and a device for melt spinning and cooling a plurality of
monofilaments of a generic type such that a large number of
monofilaments can be extruded and cooled under conditions as
homogenous as possible.
[0006] The objective is attained according to the invention for a
method for melt spinning and cooling a plurality of monofilaments
such that the monofilaments are divided after the extrusion into
several filament groups comprising several monofilaments and that
the filament groups are redirected individually and independently
of each other inside the cooling bath at several deflection
positions.
[0007] The solution by the device according to the invention is
given such that the deflection means are arranged underneath the
spinneret such that the monofilaments can be divided after
extrusion into several filament groups comprising multiple
monofilaments and that the filament groups are redirected
independent from each other inside the cooling bath at several
deflection positions.
[0008] Advantageous further embodiments of the invention are
defined by the features and feature combinations of the respective
dependent claims.
[0009] The invention allows for the monofilaments essentially being
pulled off straight in the area between the spinneret and the
deflection means. The deflection positions inside the cooling bath
may be adjusted each to the monofilaments of the filament group and
the position of the respective nozzle openings for extruding at a
spinneret. The adjustment of the relative positions of the nozzle
openings to the spinneret and the deflection position in the
cooling bath in reference to each other allow for the monofilaments
to be homogenously pulled off the spinneret. Additionally it is
achieved here that each of the monofilaments travels over an
equally long cooling distance of environmental air until reaching
the cooling liquid.
[0010] In order to minimize the friction acting during the
redirection of the filament groups at the monofilaments, it is
provided according to an advantageous further development of the
invention that the filament groups are redirected at each of the
deflection positions by individual, freely rotating deflection
rolls. For this purpose, each of the deflection means is formed by
a freely rotating deflection roll, so that the filament groups can
be guided in the deflection positions in a low-friction manner even
at redirection angles >90.degree..
[0011] In order to limit the number of deflection means required
for redirecting a very large number of monofilaments, the further
development of the invention is particularly beneficial in which
after extrusion the monofilaments are guided within their filament
group between the spinneret and the deflection position with a
maximal redirection of >5.degree.. For this purpose, in the
device according to the invention the positions and/or the number
of deflection means underneath the spinneret are selected such that
the monofilaments when pulled off the spinneret avoid a redirection
angle >5.degree..
[0012] In general, the positions and the number of deflection means
can be adjusted to the respective position and arrangement of the
nozzle openings at the bottom of the spinneret. However, the
monofilaments are preferably extruded next to each other in an
annular arrangement, with the separation of the filament groups
advantageously also occurring within the annular arrangement. For
this purpose, the deflection means are preferably positioned
underneath the spinneret in an arrangement congruent to the
formation of the filament groups in reference to the nozzle
openings of the spinneret.
[0013] Depending on the filament titer of the monofilaments and
depending on the polymer material, it is necessary to allow
differently long cooling paths. This can be realized advantageously
in a further development of the invention, in which the deflection
positions of the filament groups are embodied in an adjustable
fashion. For this purpose the deflection means are preferably
arranged at a plate-shaped fastener, which is embodied mobile to
adjust the deflection positions.
[0014] In this way, pulling the monofilaments off the cooling bath
can preferably be improved such that the fastener is connected to a
carrier by a pivotal axis, by which an angle of inclination can be
adjusted at the fastener. This way, height-adjusted deflection
positions develop so that the monofilaments can be directly guided
out of the cooling bath without any additional redirection.
[0015] The cooling path for cooling the monofilaments is preferably
embodied by a height adjustment of the fastener. Here, the
deflection positions inside the cooling bath can be adjusted in
order to shorten or lengthen the cooling path.
[0016] In the following, additional advantages of the method
according to the invention are described based on the exemplary
embodiments of the device according to the invention with reference
to the attached figures.
[0017] They show:
[0018] FIG. 1 schematically, a side view of a first exemplary
embodiment,
[0019] FIG. 2 schematically, a top view of the exemplary embodiment
of FIG. 1,
[0020] FIG. 3 schematically, another exemplary embodiment of a
cooling bath with integrated deflection means,
[0021] FIG. 4.1
[0022] and
[0023] FIG. 4.2 various views of the deflection means of the
exemplary embodiment of FIG. 3,
[0024] FIG. 5 schematically, a cross-section of another exemplary
embodiment of the device according to the invention for performing
the method according to the invention.
[0025] FIGS. 1 and 2 show a first exemplary embodiment of the
device according to the invention to perform the method according
to the invention in several views. FIG. 1 shows the exemplary
embodiment schematically in a side view and in FIG. 2 the exemplary
embodiment is shown in a top view without any spinneret. If no
explicit reference is made to the figures, the following
description applies to both figures.
[0026] For melt spinning and cooling a plurality of monofilaments,
the exemplary embodiment comprises a spinneret 1, which is
connected via a melt supply 3 to an extruder 2. The spinneret 1
comprises at its bottom a plurality of nozzle openings 4 (here,
only one nozzle opening is shown in a partial cross-section).
Underneath the spinneret 1 a cooling bath 5 is arranged, which is
filled with a cooling liquid 6, preferably with water. Inside the
cooling bath 5, several deflection means 7 are arranged at a
distance from each other in the vertical direction underneath the
spinneret. The deflection means 7 are provided in a congruent
arrangement in reference to the nozzle openings 4 at the bottom of
the spinneret 1 such that the monofilaments extruded from the
nozzle openings 4 of the spinneret 1 can be guided to a deflection
means 7 as a filament group 14 comprising several monofilaments in
a path as straight as possible. In this example, the nozzle
openings are embodied in an annular arrangement at the bottom of
the spinneret 1. As discernible from the illustration in FIG. 2,
accordingly the deflection means are also positioned in an annular
arrangement in the cooling bath 5. The deflection means 7 are held
off-set in their height in reference to each other inside the
cooling bath 5, so that the filament groups 14 after redirection at
the deflection means 7 can be jointly guided out of the cooling
bath 5 in a diagonal thread progression.
[0027] At the outlet side of the cooling bath 5, a comb-shaped
guide bar 12 is arranged, performing a separation of the
monofilaments of the filament group 14 so that after leaving the
cooling bath the filaments can be guided as assemblages 15.
[0028] A suction device 10 and a pull-off means 8 are arranged
downstream in reference to the cooling bath 5. The suction device
10 comprises several suction nozzles 11 in order to suction off any
cooling liquid adhering to the monofilaments.
[0029] The pull-off means 8 comprises several projecting godets 9,
which are driven at a circumferential speed required for pulling
off the monofilaments. In this exemplary embodiment, the pull-off
means 8 are embodied with a total of four godets 9, with the
filament assemblages 15 being guided at their circumference in a
simple loop.
[0030] In order to perform the method according to the invention, a
granulate of a thermoplastic material is added to the extruder 2 of
the device according to the invention. For example polypropylene,
polyamide, or polyester may be used as thermoplastic materials.
After melting the granulate inside the extruder 2, the melt of the
thermoplastic material is fed under pressure to the spinneret
nozzle 1. At the bottom of the spinneret 1 the melt is extruded
through the nozzle openings 4 into a plurality of monofilaments 13.
The monofilaments 13 are directly extruded into the cooling liquid
6 of the cooling bath 5. In order to guide the monofilaments 13,
several deflection means 7 are provided inside the cooling bath 5,
so that after extrusion the monofilaments 13 each are divided into
several filament groups 14 comprising several monofilaments each
and the filament groups 14, independent from each other, being
individually redirected inside the cooling bath 5 into several
deflection positions determined by the deflection means 7. Here,
the monofilaments 13 are essentially guided between the spinneret 1
and the deflection means 7 in a straight thread projection without
essential redirections. This way, particularly the entering of the
monofilaments 13 into the cooling liquid 6 can be performed under
identical conditions for all monofilaments. Therefore, even a high
number of monofilaments 13 can be cooled essentially without any
different oblique distortion. This results in a high material
homogeneity of all monofilaments.
[0031] After each of the filament groups 14 has been independently
redirected by the separate deflection means 7, all monofilaments 13
are separated after being pulled out of the cooling bath 5 by the
comb-shaped guide bar 12 so that for the further progression for
thermal treatment and stretching of the monofilaments a parallel
guiding of the monofilaments 13 is possible within the filament
assemblages 15.
[0032] In the exemplary embodiment of the device according to the
invention shown in FIGS. 1 and 2, the redirection of the filament
groups occurs in the deflection positions preferably by freely
rotating deflection rolls so that a low-friction guidance of the
monofilaments is possible. However, alternative deflection means
can also be used, such as rods or pins, for example, depending on
the material selected for the monofilaments.
[0033] When pulling off the monofilaments in several filament
groups, it has shown that for upholding a quality for all
monofilaments as homogenous as possible, the redirection of the
monofilaments during extrusion and entering into the cooling liquid
shall be maintained at a redirection angle <5.degree., if
possible. Here, the deviation between the thread guidance and a
central axis extending vertically in reference to a nozzle opening
shall be considered the deflection angle. For example, in a one-row
annular arrangement of the nozzle openings 4 at the bottom of the
spinneret 1, the deflection means 7 is positioned in a central axis
of a nozzle opening 4. The nozzle openings 4 adjacent at both sides
of the nozzle opening 4 may be allocated to the same deflection
means 7 so that the monofilaments 13 extruded from the three nozzle
openings jointly form the filament group 14 allocated to the
deflection means 7.
[0034] In order to allow designing the deflection positions inside
the cooling bath 5 as flexible as possible, another exemplary
embodiment for fixing and arranging the deflection means 7 in a
cooling bath 5 is shown in FIG. 3. In this exemplary embodiment,
the deflection means 7 are formed by freely rotating deflection
rolls 20. The deflection rolls 20 are arranged at a plate-shaped
fastener 16. The fastener 16 is fastened to a carrier 17. The
carrier 17 is held via a base plate 24 directly at the bottom of
the cooling bath 5.
[0035] In order to explain the adjustment options of the deflection
rolls and thus the deflection positions determined for adjustment,
reference is additionally made to FIGS. 4.1 and 4.2. FIG. 4.1
schematically shows the fastener 16 fastened at the carrier 17 in a
perspective view, and FIG. 4.2 shows the same in a schematic top
view. The plate-shaped fastener 16 comprises a central fixing
opening 18 with a fixing collar 19 extending parallel in reference
to the carrier 17. The fixing collar 19 is connected via a pivotal
axis 21 and a fixing screw 22 to the carrier 17. The fixing screw
22 is inserted into a guide slot 23 of the fixing collar 19 so that
by way of loosening the fixing screw 22 the fixing collar 19 and
thus the fastener 16 can be pivoted into an arbitrary incline. This
way, the deflection rolls 20 held at the fastener 16 can be
positioned inside the cooling bath at different heights in
reference to each other by the incline of the fastener 16.
[0036] In order to adjust the height of the fastener 16 the pivotal
axis 21 can be arranged between the fixing collar 19 and the
carrier 17 at different positions at the fastener 17. For this
purpose, the fastener 17 comprises several openings to accept the
pivotal axis 21.
[0037] In order to yield a redirection of the filament groups in
the same direction at the deflection rolls 20 held in an annular
arrangement, the fastener 16 comprises two recesses 25.1 and 25.2
so that the deflection rolls 20 facing the recesses 25.1 and 25.2
of the fasteners 16 are enwrapped in the same direction in
reference to the opposite deflection rolls 20 at the edge of the
fastener 16.
[0038] The exemplary embodiment shown in FIGS. 3, 4.1 and 4.2, to
arrange the deflection means inside the cooling bath is only one
potential variant of an embodiment, though. FIG. 5 schematically
shows in a cross-section another exemplary embodiment of the device
according to the invention for performing the method according to
the invention. In this exemplary embodiment, a support 26 is held
at the bottom of the spinneret 1 in the center of the spinneret 1,
projecting with its free end into the cooling bath 5. At the free
end of the support 26 a plurality of support arms 27 is arranged
spreading apart, which at their ends each carry a deflection means
7. At each deflection means 7, for example a deflection roll, here
a filament group 14 with essentially straightly guided
monofilaments 13 can each be redirected inside the cooling bath 5.
The filament groups 14 are deflected separated from each other by
deflection means 7 held at the ends of the support arms 27 and
jointly guided to a guide roll 29 arranged in the cooling bath 5.
Via the guide roll 29, the monofilaments 13 are pulled off the
cooling bath 5 in the form of assemblages 15 and separated by a
guide bar 12 arranged at the outlet side of the cooling bath 5.
This exemplary embodiment is particularly suitable for spinneret 1
with an annular arrangement of the nozzle openings 4. The support
26 fastened at the bottom of the spinneret 1 may be embodied for
example by a telescopic variant of the embodiment such that the
deflection means 7 for adjusting the deflection position can be
adjustable in their height. Additionally, the support arms 27 can
be arranged at a head piece embodied pivotal in reference to the
support 26. Here, the monofilaments may directly and diagonally be
pulled off the cooling bath 5, too.
[0039] The method according to the invention and the device
according to the invention are therefore particularly suitable to
produce a plurality of monofilaments with a homogenous quality.
Additionally, here the handling as well as the processing safety
can be improved for the guidance of the monofilaments through the
cooling liquid. By adjusting the height and the angle of the
deflection means in reference to each other, the processing time
inside the cooling bath can be changed and adjusted depending on
the material of the monofilaments.
[0040] List of Reference Characters [0041] 1 spinneret [0042] 2
extruder [0043] 3 melt supply [0044] 4 nozzle opening [0045] 5
cooling bath [0046] 6 cooling liquid [0047] 7 deflection means
[0048] 8 pull-out means [0049] 9 godets [0050] 10 pull-out device
[0051] 11 suction nozzle [0052] 12 guide bar [0053] 13 monofilament
[0054] 14 filament group [0055] 15 assemblages of monofilaments
[0056] 16 fastener [0057] 17 carrier [0058] 18 fixing opening
[0059] 19 fixing collar [0060] 20 deflection roll [0061] 21
pivoting axis [0062] 22 fixing screw [0063] 23 guide slot [0064] 24
base plate [0065] 25.1, 25.2 recess [0066] 26 support [0067] 27
carrier arm [0068] 29 guide roll
* * * * *