Note: Descriptions are shown in the official language in which they were submitted.
f
1~43~97
This invention relates to a novel spun yarn having a
unique configuration and to a process for the manufacture thereof.
. .
More particularly, this invention relates to a novel spun yarn
which gives improved efficiency in the manufacture of knitted
and woven fabrics and imparts useful properties to the knitted
and woven fabrics. The invention also relates to an effective
process for the manufacture of such novel spun yarn.
In general, conventional yarns to be used for the
manufacture of knitted and woven fabrics are classified into
spun yarns and filament yarns.
Although conventional spun yarns have good bulkiness
and are accordingly characterized by softness and warmness, they
are limited in their uniformity of yarn evenness. More particul-
arly, when fine yarn is ma~ufactured from fibers of coarse
--~ denier, the yarn evenness becomes remarkably more non-uniform.
; ~hus, knitted and woven fabrics made from conventional spun
yarn~ are lacking in surface uniformity and it is especially
~ difficult to manufacture knitted and woven fabrics of high gaug~.
- On the other hand, conventional filament yarns have
~ 20 good uniformity and fine yarns can be manufactured. However,
they are lacking in bulkiness and, therefore, knitted and woven
~:` fabrics made from them, although having a uniform surface, are
cold and slim-featured. MuCh research effort has been directed
~; towards removing these defects of the conventional yarns, and
many methods have been proposed for this purpose.
- Conventional methods for obtaining spun yarns are
;` classified into the card system and the tow system. The tow
system includes the perlock system, the tarbo stapler system,
the converter system and the direct spinning system. In the card
-1-
- '' ' `''
.
- i~43~?7
- system, wherein spun yarn is made by opening and rearranging
staple fibers from a fiber mass in which the staple fibers are
arranged rando~ly, the spun yarn obtained is limited in evenness
; and it is said that the limit of evenness of the spun yarn
corresponds to that of random slivers.
. . ,
In other words, when the average number of fibers in
cross sections of spun yarn is N, the rate of yarn evenness
of random slivers, CVO, is the following.
:. cvO = loo/J~
And the rate of yarn evenness in the spun yarn obtained by the
card system is always beyond the value of the above equation.
The rate of yarn evenness means a coefficient of
variation in unevennes~ of fineness of spun yarn, and the lower
the value, the better the evenness of yarn. In the tow system,
the method of obtaining staple fibers from tow is either to
: : .
-- tear off the tow or to cut the tow with a knife.
In the latter case, the end portions of staple fibers
obtained are centralized at a specific position along the length
,. . .
of sliver, and therefore a useful yarn cannot be obtained. In
order to disperse the cut end portions of staple fibers, doubling
and drafting are repeated, so that the uniformity of fineness of
- the spun yarn obtained is almost equal to the uniformity in spun
yarn obtained by the card system. In the former case, i.e. the
method of obtaining sliver by tearing off, the uniformity of
thickness of the sliver is deemed to be as follows. The number
of filaments, which compose a supplying tow, is represented as
n, and it is supposed that all of the filaments are of the same
fineness and that the elongation of each filament at tearing
off is perfectly recovered. when the tow is torn off at drafting
-2-
1~3197
f D times to obtain sliver, the average number of fibers in
the cross section of the tow becomes n/D. Further, supposing
that the cutting of filaments takes place randomly, the proba-
bility p of there existing one of the filaments in any given
cross section of sliver becomes 1/D and probability q of its
non-existing become~ p).
p = l/D
q = 1 - p
~he number of fibers in the cross section of the sliver is
obtained by adding them n times, and as a result of binomial
distribution, the probabili y P(r) of the number of fibers in
the cross section being r becomes the following.
P(r) = nCrprqn~r
As the dispersion of data is a binomial distribution is n.p.q
and the average value is n.p, the CV% of the data becomes the
- following.
~n P q x 100 = ~ x 100 = ~ x 100(/) -
n.p ~n.p J n
. . .
In other words, when a tow, which is composed of n
filament pieces, is torn off at a drafting of D times to obtain
;sliver, supposing that the cutting of filaments takes place
randomly, the CV% of the number of fibers in cross section,
becomes ~ x 100%.
On the other hand, the CV% of the above mentioned
random sliver is 100 %. N is the average number of fibers in
cross section, corresponding to n/D in the case of sliver
obtained by tearing off the tow, and accordingly the ratio of
the CV% of the torn-off sliver to the CV% of the random sliver
becomes the following.
--3--
.
.
'
:- 10~3~97
.' x 100 ~
;~ ¦ D x 100 D
~ ~: J n
Generally, in the case of torn-off sliver, the drafting
ratio D is much greater than 1 and the value of above equation is
almost equal to 1. Therefore, even in the case of torn-off
sliver, the uniformity of fineness in the spun yarn obtained is
at most the same as the uniformity in the random sliver. As is
mentioned above, the conventional ~pinning methods are limited
in the uniformity of thickness in the spun yarns obtained.
on the other hand, many methods have been proposed to
impart hand feel like spun yarn to filament yarns, as shown in
Japanese Patent PublicatiOns Nos. 36-6592, 40-19697 and 49-133639,
in which methods of making nap on the surface of filament yarn
, ~ ~
: are proposed. However, even though the yarns obtained by these
- methods have nap on the surface of yarn and are apparently
similar to spun yarn, their bulkiness and softness, and the hand
feel of the surface of knitted and woven fabrics made from them
are greatly inferior to those of spun yarns.
Another method of manufacturing yarn similar to spun
;. .
yarn from filament yarn has been proposed in Japanese Patent
Laying Open No. 50-154550. According to this method, an
unoriented polyester yarn is subjected to drafting and heat treat-
ment under specific conditions to impart weak points to the
filaments and the yarn is torn off to obtain yarn similar to
spun yarn.
The end portions of the fibers obtained by this method
are not only on the surface of yarn but also inside the yarn and,
therefore, the yarn obtained by this method is more similar to
spun yarn than those obtained by the above-mentioned conventional
methods. However, according to this method, the weak points are
--4--
-` 1043197
quite randomly distributed in each filament, so that the lengths
of the fibers obtained are quite irregular.
Well known methods for manufacturing blended yarns
are methods of blending plural staple fibers in a scutching
process and methods of blending plural slivers in a drawing
process or a gilling process. ~owever, the blended yarns
obtained by these methods give rise to problems of non-uniformity
of fineness and of low productivity.
Covered yarn is a yarn in which the function of the
core component of the yarn is to improve the mechanical pro-
perties of the yarn (such as its stretchability, and bending
strength) and the function of the covering component is to ;
improve the aesthetic properties of yarn (such as its color,
~ and hand feel). A typical known method for manufacturing covered
,,,- :,
- yarn is a method in which a core yarn is fed onto a front roller
of a ring spinning frame, and is discharged together with a
drafted fleece from the front roller, the yarn thus produced
being twisted and taken up.
HoweVer, this method is not efficient because of the
; 20 use of a roving yarn in long spinning processes. Also, in
- this method, the fleece which is produced by drafting the roving
yarn is limited in its uniformity of thickness, so that an
uneven covering tends to appear and lowers the quality of knitted
and woven fabrics made from the covered yarn.
It is known that doubling yarn can be directly
manufactured by using a pot spinning frame, in which a drafted
roving yarn is fed into a cylindrical pot which is rotating at
a high speed to twist it, and when the volume of yarn in the
pot reaches a predetermined level, the yarn is discharged
-5-
" ' ' ~"'~ .
1043197
together with a separate yarn, and the doubling and twisting
yarn thus produced is taken up as a cheese. This method is
superior to the methods using a ring spinning frame which require
four steps of spinning, rewinding, doubling and twisting.
HOwever, this method has several problems in practice.
A first problem is that it is required to stop the
rotation of the pot at the time of yarn breakage. As is well
known, when using a pot in the spinning process, the fiber
bundle is pressed against the inner wall surface of the pot by
:.-
; 10 the action of centrifugal force, but when the rotation of the
pot is stopped, the fiber bundle inside the pot gets out of
shape. Accordingly, when yarn breakage occurs in the pot, the
:~ whole yarn therein becomes yarn waste.
A second problem is that it is necessary to rewind the
wound yarn in order to remove yarn defects such as slub and-nep.
, This problem is especially troublesome when staple fiber is used
` as a starting material for the spun yarn. Moreover, when removing
yarn defects from doubling yarn, the knot portion of the yarn
becomes enlarged.
As is mentioned above, the conventional pot spinning
methods present various problems and, especially, it is very
diPficult to prevent a reduction of efPiciency and yield caused
by the occurrence of yarn breakage.
An object of this invention i5 to provide a spun yarn
having increased yarn strength without unevenness of yarn.
Another object of this invention is to provide a
blended spun yarn composed of at least two kinds of staple fibers,
with less unevenness of blend in the radial and longitudinal
directions of the spun yarn. Further, another object of this
:~ f
10~3197
Invention is to provide a covered yarn with less unevenness of
fineness of the covering part of fiber bundle.
Further, another object of this invention is to provide
a method for manufacturing the above-mentioned spun yarn directly
from continuous multi-filament yarn.
The spun yarn of this invention is composed substan-
tially wholly of staple fibers and the average number N of fibers
in the cross section and the rate of yarn evenness CV are such
that the product CV ~ is within the range of 12.5 ~ CV ~ <100.
In the above inequality the rate of yarn evenness CV is a
coefficient of variation in evenness of fineness as shown above,
.,,
and, in more detail, is a value obtained by multiplying 1.25 by
a value showing the average variation value of evenness as a
percentage, in which the average variation value of evenness
n~ is measured at 25 m/min. by usingi~Yk~ yarn evenness tester
in accordance with Japanese Industrial standard JISL 1008,
' cotton yarn testing method 5.18.Z, B,I.
~;. ..
; The staple fibers to be used in this invention are
- those obtained by cutting continuous multi-filament yarn, pre-
ferably of polyamide or polyester type synthetic fibers. The
effective fiber contents of the staple fibers to be used in
this invention are preferably more than 25%.
The effective fiber contents are obtained as follows.
Staple fibers are arranged in order of their length,
and a so-called staple diagram is prepared. At one end, the
longest fiber is arranged and at the other end the shortest is
arranged and the distance between thern is divided into 50 equal
parts.
49 division points are accordingly obtained and the
total fiber length~ at all of the division points are measured.
_7_
. .
'
. .
: - ` 1043197
A value obtained by adding the average of the longest fiber
length and the shortest fiber length into the above total fiber
length is divided by 50 to give the average fibre length ~e .
The effective fiber contents are shown as a percentage of the
number of staple fibers within 0.8~ ~ 1.2~e length per the total
number of staple fibers. Therefore, the better the uniformity
of the length of staple fibers, the higher the effective fiber
contents.
he ends of staple fibers in the spun yarns of this
, .
invention are present randomly inside and on the surface of
yarn.
The staple fibers constituting the spun yarn of this
invention may be either non-crimped or coil-like crimped fibers.
. . .
Moreover, the spun yarn of this invention may be composed of at
least two kinds of staple fibers, both of which are blended
with each other in the cross section of yarn.
In the above blended spun yarn, the average number of
- fibers, Nl, N2 ~ and the rate of yarn evenness, CVl, CV2
of each of staple fibers are as follows.
12.5 < CVl < 100
12.5 CV 100
,__ < 2 <
~ `/N2 ~N2
.
In the above inequalitites, the average number of
fibers and the rate of yarn evenness are obtained by counting
the number of fibers on 50 cross sections taken at random of
the spun yarn by means of microscope.
-8-
10~3~97
Moreover, this invention provides a composite yarn
which is composed of staple fibers, having the average number
of fibers in cross section, N, and the rate of yarn evenness,
CV, such that the inequality 12.~ ~ CV ~ ~ 100 is obeyed, and
a further yarn. As the further yarn, multi-filament yarn,
monofilament yarn, spun yarn, textured yarn, elastic yarn, and
the like, can be used.
: ~.
Covered yarn can be manufactured by using the above-
mentioned further yarn as the core yarn components. Spun yarn
- 10 of this invention can be manufactured as follows.
substantially non-twisted continuous multi-filament
yarn fed from a feed roller is contacted with a cutter moving
~, approximately at right angles to the yarn axis so as to cut it
into staple-like fibers while maintaining the continuity of the
iber bundle, and is discharged by means of delivery roller
rotating at the same surface speed as the surface speed of the
feed roller, and then the fiber bundle thus obtained is gathered
. .
and taken up.
:.,
The starting material for manufacturing the yarn of
; 20 this invention is continuous multi-filament yarn which is pre-
ferably non-twisted and in which each continuous filament is
separated from the others.
According to this invention, as the continuous filaments
constituting the continuous multi-filament yarn are cut into
staples, the continuity of the fiber bundle composed of the
staple-like fibers thus produced is maintained. Therefore, it
is preferable that the cut points of the continuous filaments
are dispersed as randomly as possible. For this reason, the
continuous multi-filament yarn is required to be non-twisted,
_g _
,",
,
10~3197
and a multi-filament yarn having a twist density of less than
100/m is preferably used.
~ If the twist density is substantially higher than the
; ~ above value or if the continuous filaments are tightly fixed to
each other with adhesive, resin or heat welding, only filaments
exposed on the surface of the continuous multi-filament yarn are
cut, and the filaments existing in the center parts thereof are
; not cut and remain in the continuous state. In such a case, the
whole of the continuous multi-filament yarn cannot be cut into
uniform staple-like fibers while maintaining continuity of the
fiber bundle.
The number of filaments constituting the continuous
multi-filament yarn is preferably 15 or more. The more the
c~rr~"~
filaments, the better the ~ff~t'~7 of the fiber bundle composed
of staple-like fibers which is obtained.
In the above method, the ratio of the surface speed
of the delivery roller (or second feed roller) to the surface
speed of the feed roller (or first feed roller) is usually
. within 1.01 - 1.20. The bending angle of the continuous multi-
filament yarn in contact with the cutter is usually within 15 -
45. The cutter is preferably composed of a hollow cylindrical
rotary device and the continuous multi-filament yarn is cut by
contacting it with the inner wall of said cylindrical rotary
device.
The speed of the hollow cylindrical rotary device is
preferably at least 1,000 rpm. As the supplying yarn, at least
two kinds of substantially non-twisted continuous multi-filament
yarn can be used, or substantially non-twisted and non-crimped
or spiral crimped continuo~ls multi-filament yarn can be used.
,' -10-
~, 1043197
- Moreover in the above process, composite yarn can be manufactured
by joining the cut fiber bundle together with another yarn fed
from the delivery roller. In this case, covered yarn can be
manufactured by feeding the other yarn in a state of tension
higher than the cut fiber bundle. Also, stretch core yarn can
be manufactured by using elastic fibers as the above-mentioned
other yarn. According to another embodiment of this invention,
substantially non-twisted aontinuous multi-filament yarn is
- contacted, through a feed roller, with a cutter moving approxi-
mately at right angles to the yarn axis, is cut into staple-like
fibers while maintaining the continuity of fiber bundle, and is
discharged by means of a delivery roller at a speed approximately
equal to the surface speed of the feed roller. The fiber bundle
is introduced into a pot rotating at a high speed and is twisted,
and then at the time when the yarn content in the pot reaches a
predetermined level, the yarn deposited in the pot and the yarn
coming continuously into the pot are double discharged from the
pot in a twisted condition and are taken up as a doubled and
twisted spun yarn.
The invention will now be more fully described, by way
of example only, with reference to the accompanying drawings in
which:-
Figure 1 is a side view schematically illustrating
one embodiment of apparatus for practicing the invention;
~ Figure 2 shows the cutter used in the apparatus partly
- in section;
Figure 3 schematically illustrates the cutting process;
Figure 4 illustrates an alternative arrangement of cut-
; ting devices;
--11--
'
"' ' '
- -` 10~319~
Figure 5 ~hows a further form of apparatus for carrying
:. .
out the invention;
; Figure 6 shows apparatus for producing blended spun
yarn;
. - :
. i: ,,
Figure 7 shows apparatus for producinq covered spun
- yarn: and
. .
~ . ~
FigureS8 and 9 show the operation of apparatus for
producing doubled yarn.
,.~
In the apparatus of FigUre 1, continuous multi-filament
yarn 2 taken up from a package 1 is supplied through a first
feed rollers 3 into a cutter 4 which is provided between the
feed rollers 3 and de~very rollers 5, the cut staple-like fiber
bundle 2a being discharged by the delivery rollers 5. Then, the
cut staple-like fiber bundle 2b is supplied into a twisting
machine 9, which is e~uipped with a ring 6, a spindle 7 and a
traveler 8, and lS taken up on a pirn 10.
As the cutter to be used in this invention, a hollow
cylindrical rotary device as shown in FigUre 2 is preferably
used. This compriseq a hollow cylindrical rotary device 4a
connected with a hollow spindle 4c through a supporting device 4b.
The continuous multi-filament yarn is contacted with
~- the inner surface of the hollow cylindrical rotary device 4a.
; The portion of the cutter in contact with the continuous
multi-filament yarn has an abrasive surface composed of, for
instance, sand or like abrasive particles having sharp edges.
The ratio of the surface speed of the second delivery
rollers 5 to that of the first feed rollers 3 is of importance
in order to cut the continuous filaments of continuous multi-
filament yarn into good staple-like fibers, and preferably is
.
-12-
,i . , ~
` 1043~ 9~
Within the range 1.01 - 1.20. If the ratio is less than 1.01,
an adequate cutting of the filaments cannot be attained. -
If the ratio is greater than 1.20, it is difficult to
maintain the continuity of the fiber bundle composed of staple-
like fibers which is produced by cutting the continuous filaments
.~: .
~ of the continuous multi-filament yarn, and accordingly it
.'.
becomes difficult to manufacture the spun yarn continuously.
If a ratio of less than 1.01, for instance, 1 must be
used, the multi~filament yarn must be given a pretension before
said yarn reaches the feed rollers of the same magnitude as the
tension which would be given to the multi-filament between the
feed rollers and delivery rollers in the procedure described
; above. -~
The speed of rotation of the hollow cylindrical rotary
device 4a and the bending angle of the continuous multi-filament
; yarn presented in contact with the inner surface of hollow
cylindrical rotary device are related to the cutting efficiency.
The rotation speed of the hollow cylindrical rotary -
device is preferably at least 1,000 rpm. If the rotation speed -
is less than 1,000 rpm., the cutting of the filaments is insuf-
~; ficient. The bending angle is preferably within 15 - 45. If
the angle is less than 15, an adequate cutting of the filaments
cannot be attained. If the angle is more than 45, the cutting
point is centralized, and accordingly it is difficult to manufac-
ture the spun yarn continuously and the strength of obtained
spun yarn is lowered remarkably. According to this invention,
substantially non-twisted continuous multi-filament yarn is
cut by means of the hollow cylindrical rotary device and rollers
into staple-like fibers and the product is discharged in the
-13-
. .
:: 1043197
form of a continuous fleece-like staple fiber bundle.
Figure 3 briefly shows this cutting process. In
Figure 3, the step in which one of the continuous filaments is
cut is shown, and the thread line between the feed rollers 3
and the delivery rollers 5 is shown as a straight line for the
sake of brevity of explanation.
At (a) is shown a state just prior to the cutting of
the continuous filament 2 by means of the cutter 4 (hollow
cylindrical rotary device). The reference letter A shows the
position of the end of the filament produced in the preceding
cutting. Supposing that the cutting position is C at which the
filament is contacted with the cutter 4, then the cut fiber
length is equal to the distance AC.
At (b) is shown the fiber's passage after cutting,
the cut fiber on the delivery roller 5 side being transfered to
the left by said roller at the same speed as said roller, and
the fiber on the feed roller 3 side being also transfered to
the left at the same speed as said roller 3. In this case, the
end of the cut fiber is supported in straight form by friction
with surrounding fibers.
At (c) is shown the state at the time when the end of
the fiber on the feed roller 3 side reaches the nip F of the
delivery roller 5. The continuous multi-filament yarn 2 is
nipped by both the first feed roller 3 and the delivery roller 5,
and begins to be elongated between the two nip points F and B
and thus reaches the state shown at (a) again. The cut fiber
length is equal to the distance between the two rollers AC which
is equal to the sum of the distance FC between the cutter 4 and
the nip of delivery rollers and the distance AF. The distance
-14-
. ,
1043197
AF is equal to the length of continuous multi-filament yarn 2
`, transferred by the delivery rollers 5 between the nip of the
delivery rollers 5 and the cutting point. ThiS length AF depend~
on the ratio R of the surface speecls of the two sets of rollers,
the distance L2 between the two sets of rollers, and the elon-
gation ~ of th~ fiber at cutting.
AF = L2 loge (R-l) (1+)
R-(l+~)
The cut fiber length L is as follows, wherein the
distance FC between the cutter 4 and the nip of the delivery
- 10 rollers 5 is shown as Ll.
- L = Ll + L2 loge ( R-(l+~
The above equation was obtained from consideration of
; the draft-cutting fiber length in tow spinning and the like but --
~; is also applicable to this invention. However, there is some
difference between the two methods. That is, in the case of the
... .
draft-cutting by the known method, the cutting positions of the
fibers are not constant and Ll in the above equation accordingly
.;
changes widely. Further, the draft corresponding to R in the
above equation is much greater and the elongation of the fiber
at cutting is also greater than that ~f this invention. Therefore,
the yarn obtained by the known method has unevenness in the cut
fiber length, unevenness of fineness of the fiber bundle and an
excessive shrinking percentage. ~he cutting device can also be
arranged, shown in Figure 4, so as to treat plural multi-filament
yarns 2, in which plural cutting devices 4 are arranged between
.
plural feed rollers 3 and plural delivery rollers 5.
In Figure S, a feed roller 3a is used in place of the
first and second feed rollers, and the multi-filament yarn 2 is
- supplied, through the feed roller 3a, to a guide roller 11, and
; -15-
. . ~.
~ ` 1043197
is cut by the cutter 4 prior to returning to the feed roller 3a
and then is discharged as staple fiber bundle. As the means
for joining the fibers in the form of yarn, a twisting method
using a ring traveler system, a twisting method using an open-end
spinning system, a self-twisting method or an adhesive method
combining false twisting and heat adhesion can be used. As the
non-twisted continuous multi-filament yarn to be used in this
invention, crimped yarn such as false twisted yarn can be used.
This crimping process can be incorporated into the process for
manufacturing spun yarn of this invention.
The process for manufacturing the spun yarn of this
invention can be incorporated into the process for manufacturing
the continuous multi-filament yarn used as the starting material.
Also, as the continuous multi-filament yarn, yarn com-
posed of dirferent components can be used, the components differ-
ing, for example, by being different kinds of fibers, different
filaments, or having different crimped forms or different
shrinking percentages.
As is shown in Figure 4, using plural cutters arranged
in a row, cut fiber bundles each of which have different fiber
length can be joined to produce a blended spun yarn.
Figure 6 shows one embodiment of apparatus for manu-
facturing a blended spun yarn in this invention.
Different kinds of continuous multi-filament yarns 2,
2' taken up from the package 1, 1' are guided and supplied
through feed rollers 3 into the hollow cylindrical device 4a
which is provided between the first or feed rollers 3 and the --
delivery rollers 5 to be cut into staple-like fibers, and are
blended through the positions of the bundles being changed
. ~
-16-
~ ~0~3197
relative to one another. The blended fiber ~undle 2a is discharged
by the delivery rollers 5. Then, the fiber bundle 2a thus produced
is supplied into a twisting device 9 which is equipped with a ring
6, a spindle 7 and a traveler 8 to be twisted and taken up on a
~;`- pirn 10.
. . .
Figure 7 shows one embodiment of apparatus for manufac-
turing a covered spun yarn in this invention.
Continuous multi-filament yarn 2, which is the starting
material for the covering part, is supplied through the first or
feed rollers 3 into the hollow cylindrical device 4 and delivered
through the delivery rollers 5~
The other yarn 12, which is the starting mRterial for
: .
the core part, is supplied by a third feed roller 13 from a
~; package 14 and is joined with the fiber bundle 2a at the second or
delivery rollers 5.
;~ The united bundle is delivered from the second rollers 5,
and is twisted by the spindle 7 and the ring traveler 9, and is
taken up on the pirn 10 as oovered yarn. In this case, the said
..... .
other yarn 12 is preferably supplied in a state of ten3ion higher
- 20 than the fiber bundle 2a. As the said other yarn, an elastic yarn
- such as polyurethane yarn can be used.
Covered yarn having high stretchability can be obtained
Y by supplying the elastic yarn in a tensioned state to the delivery
rollers 5.
: Figures 8 and 9 show one embodiment of apparatus for
manufacturing doubled yarn in this invention.
The continuous multi-filament yarn 2 is supplied from the
package 1 through the feed rollers 3 into the cutter 4 whieh is
provided between the feed rollers 3 and the delivery rollers 5. The
,
- 17 -
,'
.
.
f -~
1043197
- ` c~t staple-like fiber bundle 2a is delivered by the delivery
rollers 5 and is introduced through a yarn guide pipe 16 into a
pot 17 rotating at a high speed.
The yarn guide 16 is in reciprocatirlg motion so as to
make a uniform yarn layer 18 in the pot 17.
The yarn 19 guided into the pot 17 is pressed against
the inner surface by centrifugal force to ~orm the yarn layer 18
and is twisted as a result of the rotation of the pot 17. In the
drawing, 20 indicates take-up rollers, 21 is a taking-up drum and
22 is a taking up bobbin.
In the above mentioned operation, the yarn layer 18
increases with time, and when the yarn layer reaches a predetermined
level or after a predetermined time from the starting of yarn
storage in the pot 17, the yarn pas~ing through the yarn guiae
pipe 16 is discharged downwards together with yarn from the yarn
layer through a yarn discharge pipe 23 and is taken up through the
take up rollers 20 onto the bobbin 22 by means of the taking-up
. . .
drum 21, as shown in Figure 9.
The direction of travel of the yarn discharged from the
yarn layer 18 stored in the pot 17 is reversed as compared with
its former direction, and accordingly the yarn becomes reversely
twisted as it is discharged together with the yarn 1~ supplied
by the yarn guide pipe 16 through the yarn discharge pipe 23. A
doubled yarn is thus obtained, and when the yarn layer 18 in the
pot 17 is exhausted, discharging of the doubled yarn from the yarn
discharge pipe 23 is stopped and storage of yarn into the pot 17
is started again.
By repeating the above-mentioned steps, doubled yarn 24
made of spun yarn is manufactured directly from the continuous
- 18 -
":
. ~ , . , ~ ':
- , . ' ',
multi-filament yarn 2. 1043~97
The advantages of this invention can be summarized as
follows.
(1) The spun yarn of this invention has excellent uniformity
of thickness as shown by the average number of fibers in
; cross section, N, and the rate of yarn evenness, CV being
;:;
such that the inequality 12.5 < CV~N ~ 100 is obeyed,
and accordingly knitted and woven fabrics manufactured
therefrom have excellent uniformity of surface, and the
manufacture of knitted and woven fabrics can be conducted
quite efficiently. Further, knitted and woven fabrics
can be manufactured having high gauge which can not be
attained using the conventional spun yarns.
~- (2) The spun yarn of this invention is composed of staple
, . ' :'
; fibers with effective fiber contents of more than 25%,
and accordingly it has satisfactory strength, and there
is less scattering of short fibers during knitting
~ processe~ or the like.
(3) The ends of the staple fibers constituting the spun yarn
, .
of this invention exist inside and on the surface of the
: .
yarn, and accordingly knitted and w~ven fabrics having
high bulkiness, softness and warm hand feel can be
, .
, manufacturedO
(4) The spun yarn of this invention can be composed of non-
crimped staple fibers, and accordingly a spun yarn can be
manufactured having a smooth luster which cannot be
attained using the conventional methods.
. :. .
(5) The spun yarn of this invention can be composed of coil-
crimped staple fibers, and accordingly a spun yarn can
-- 19 -- .
: lV43~97
be manufactured having excellent bulkiness and stretch-
ability which cannot be attained by the conventional
methods.
(6) The spun yarn of this invention can be composed of at
least two kinds of staple fibers, having less unevenness
of blend in the radial and longitudinal directions of the
spun yarn, and accordingly may exhibit the features of
spun yarn obtained by blending different kind~ of fibers.
For instance, if differently colored fibers are blended,
natural colors can be obtained, or if fibers of different
shrinkage are blended, bulky yarn having uniform and
- higher bulkiness can be manufactured, or if fibers of
different fiber fineness are blended, higher bulkiness,
softness and resilience can be obtained.
(7) Covered yarn obtained.~using this invention employs
:.:
aontinuous multi-filam~nt yarn as a starting material
-~ for the fibers composing the covering part thereof, and
accordingly the fiber bundle composing the covering part
: . . . .
has less unevenness of thicknesQ, and knitted and
woven fabrics made therefrom have uniform surface, whiLe ;
the manufacture of knitted and woven fabrics can be
conducted quite efficiently.
(8) According to the method of this invention, spun, blended,
aovered or other yarn can be manufactured directly from
- continuous multi-filament yarn, and this penmits ration-
alization of the equipment, operating personnel and of ~-
the necessary electric power supply.
(9) Because in the method of this invention, the cut points
of each of the continuous filaments are randomly dispersed
- 20 -
,
: ~. . ..
~043197
inside and on the surface of yarn along the axial
- direction of the yarn and the effective fiber contents
of staple fibers in the spun yarn obtained are quite
high, the spun yarn obtained has high strength and high
uniformity of fineness, nap on the yarn surface and
~` high strength, and difficulties such as yarn breakage
.: .
; in the manufacture of the spun yarn are reduced
remarkably.
(10) In the method of manufacturing blended spun yarn of this
invention, the cut points of each of the continuous
filaments are rand~mly dispersed inside and on the surface
of yarn along the axial direction of the yarn and the
staple fibers are blended with each other in the cross
section of spun yarn, and accordingly difficulties such
; as yarn breakage in the manufacture of blended spun yarn
are reduced remarkably.
(11) In the method of manufacturing the covered yarn of this
invention, the covered yarn can be manufactured directly
using the continuous multi-filament yarn in the prepara-
. .
tion of the covering part and the other yarn for the
- core part~ and m~reover covered yarn can be manufactured
having in the covering fiber bundle an average number
of fibers in cross section which is smaller than that
; obtained with the conventional methods so that the
., .,~
excellent properties of core yarn can be best exhibited.
(12) In the method of manufacturing the doubled or two folded
yarn of this invention, the cheese composed of the
doubled yarn can be manufactured directly from the
continuous multi-filament yarn. Accordingly, the process
- 21 -
' , , - . ' ' . . ., ' . ~ ',
1043~97
can be simplified remar~ably, and the doubled ob-
tained has remarkably high uniformity, while the
problem of yarn breakage in the spinning process can
be almost completely avoided.
The features of this invention will be more apparent
from the following examples.
EXAMPLE 1
Using the apparatus of Figure 1, continuous multifila-
. . .~
ment yarn 2 is fed from the package 1 by the feed roller 3 into
the cutter 4 and then through the delivery roller 5 into the
twisting device 9, the twisted spun yarn 2b thus produced being
` taken up on the pirn 10.
" .
The cutter 4 is, as shown in Figure 2, equipped with
;~ the rough surface 4d which was prepared by electrically coating
` diamond powder of an average diameter of 20f~ onto the inner
surface of the outlet of the hollow cylindrical rotary device 4a.
The cutter 4 was rotated in the direction of the arrow
in Figure 1 and cut the continuQus multi-filament yarn 2 passing -~
through the hollow part into staple-like fibers to produce the
fleece-like fiber bundle 2a.
- During this cutting operation, the straight and paral-
lel state of the fibers composing the bundle was preferably
maintained, and the fiber bundle 2a was discharged by the deli-
very roller 5.
The above method was conducted by using polyester tex-
tured yarn (150 deniers, 48 filaments), a surface speed of the
first feed roller of 19.2 m/min. and the surface speed of the
second feed roller of 20 m/min., a rotation of cutter 4 of
8,000 r.p.m. and a rotation of spindle 4c of 9,000 r.p.m.
: - 104319'7
he spun yarn obtained had a rate of yarn evenness,
CV% of 6.9%, an average fiber length of fibers composing the
yarn of 82 mm and a maxi~um fiber length of 210 mm.
."; .
For the purpose of comparison, a polyester textured
yarn (150 deniers, 48 filaments), a polyester filament yarn
(150 deniers, 48 filaments) and a spun yarn composed of poly-
ester staple fibers (1.5 denier, 44 mm cut) manufactured
'according to the conventional method were prepared.
, . .
The rate of yarn evenness, CV, CV ~, and the speci-
, .
` ~ 10 fic volume of the spun yarns thus obtained were measured.
; The specific volume was calculated from the diameter
and yarn weight of cheese.
The test results are as follows:
Sample DV CV ~ Specific
Volume
spun yarn of
this invention 6.9% 49 2.37 cc/g
Filament yarn0.54 3.8 1.43
Polyester ~ex-
tured yarn 1.05 7.3 1.87
; spun yarn by con-
ventional method 16.5 166 1.94
,
The CV value of the spun yarn of this invention was
6.9% while that of the conventional spun yarn was 16.5%, and
the CV ~ value of the spun yarn of this invention was remarkably
lower than that of the conventional spun yarn, on the other hand,
the specific volume of the spun yarn of this invention was 2.37
cc/g while that of the conventional spun yarn was 1.94 cc/g.
These test results show that the spun yarn of this invention
has excellent bulkiness and uniformity.
Plain knittings of the abovementioned samples were con-
.
ducted by means of a circular plain knitting machine of 28 guage.
-23-
1~43~97
With the oonventional spun yarn, yarn breakage occurred
frequently and the knitted fabrics obtained had many defects The
other yarns knitted smoothly and the knitted fabrics obtained
thereby had no defects. Using knitted fabrics made from three
- kinds of yarns other than the conventional spun yarn, shirts and
blouses were sewn The knitted fabrics made from filament yarn
. . .
or woolie yarn were not suitable because they had no feeling of
thick cloth and they had the unpleasant feeling of sticking to
- the skin, but the knitted fabrics made from spun yarn of this
invention were quite suitable because they gave a feeling of soft-
ness and of high quality of the surface.
EXAMPLE 2
The procedures in Example 1 were repeated but making
changes in the speed ratio of the first feed roller 3 and the
delivery roller 5, the position in which the cutter 4 was set,
the inner diameter thereof, and the particle size of diamond powder
therein.
For the purpose of comparison, the spun yarns thus
. , .
obtained and three other kinds of spun yarns (sample ~os. 8 - 10)
manufactured according to the conventional card and direct spinning
systems were knitted-up by means of a circular plain knitting
machine of 28 gauge.
The test results relating to efficiency of knitting,
quality and hand feel of the knitted fabrics were as follows.
Sample Nos. 1, 3 and 10 were also tested in Example 1. ~
:
- 24 -
: . . . .
1~)43197
,................................ . ..
; Sample CV cvr of _nittin~ qualityhfaeneld
1 1.05~ 7.3 0 0 X
2 6.1 43 0 0 0
3 6.9 49 0 0 0
- 4 8.3 58 O O O
; ~ 511.5 79 0 0 0
v^ 613.0 90 0 0 0
715.4 106 X ~ 0
811.9 113 0 0 X
`; 914.9 149 ~ ~ X
__ __ 16.5 1 166 X
. ,~ ,
. : :
In the table, 0 means excellent, ~ means good or allowable
and X means bad. Sample No. 1 had excellent efficiency of knitting
.: . ~ .
: and quality of the knitted fabrics but less bulkiness and softness
. .
of surface. Sample NosO 8 - 10 were knittable insofar as a small
,~ . .
amount of knitted fabric could be obtained but had poorer quality
and hand feel.
- EXAMPLE 3
Using the process illustrated in Figure 7, and using
woolie polyester filament yarn (150 deniers, 72 filaments) as the
continuou-q multi-filament yarn for the covering part and polyure-
thane elastic yarn (30 deniexs) as the yarn for the core part, a
- covered yarn was manufactured.
the surface speed of feed roller 3 13.1 m/min.
the surface speed of delivery roller 5 1308 m/min.
the roller speed of third feed roller 13 5.5 m/min.
,': '
- 25 -
.:
;
. ' .
., ~ .
~. ..... . .
`.~, 1~431g'~
the rotation speed of spindle 11,000 rpm
the rotation speed o~ cutter 5,500 rpm
The covered yarn thus obtained had excellent uniformity
and stretchability and the covering portion was of good quality.
BXAMPLE 4
Using the process illustrated in Figure3 8 and 9,
;` doubled yarn was manufactured.
The continuous multi-filament yarn was woolie polyester
yarn (150 deniers, 48 filaments) and the surface speed of the feed
roller 3 was 19.2 m/min.
The surface speed of the delivery roller 5 was 20 m/min.
The cutter 4 had electrically coated diamond powder of
800 mesh on the inner surface 4d and had an inner diameter of
10 mm. The rotation speed of the cutter was 6,ooo rpmO
The rotation speed of the pot 17 was 8,ooo rpm~
The doubled yarn thus obtained had excellent uniformity
and fineness. There was no yarn brea~age in the spinning process.
':
''-
:
. .
- 26 -
' '' . ,.
.
.. ' . . ' :
