e YARN DEFECT DETECTING DEVICE AND WINDING DEVICE
BACKGROUND OF THE INVENTION
1. Field of t h e Invention
5 The present invention r e l a t e s t o a yarn d e f e c t d e t e c t i n g device
and a winding device.
2. Description of t h e Related A r t
Conventionally, a t e x t i l e machine such a s a yarn winding device
10 is provided with a yarn d e f e c t d e t e c t i o n device t h a t d e t e c t s a d e f e c t
included i n a yarn (yarn d e f e c t ) and removes t h e yarn (see, e . g . ,
J P 4436938) . A method described i n J P 4436938 monitors a t r a v e l i n g
yarn and, when d e t e c t i n g a d e f e c t of t h e yarn, c u t s t h e yarn a t a
downstream s i d e of t h e d e t e c t e d yarn d e f e c t t o i n t e r r u p t a winding
15 process. In t h i s method, t h e yarn is removed by a predetermined
l e n g t h .
BRIEF SUMMARY OF THE INVENTION
In t h e conventional technology described above, t h e yarn is
20 removed by a predetermined l e n g t h , so t h a t i f a length of t h e d e f e c t
is l a r g e r than t h e predetermined length, t h e removal process needs
t o be repeated s e v e r a l t i m e s . This d e t e r i o r a t e s production
e f f i c i e n c y . That is, t h e r e p e t i t i v e execution o f t h e removal process
i n c r e a s e s t h e number of yarn j o i n i n g p o i n t s , r e s u l t i n g i n
25 d e t e r i o r a t i o n i n q u a l i t y of a yarn product ( e . g . , yarn package).
An o b j e c t of t h e p r e s e n t i n v e n t i o n is t o provide a yarn d e f e c t
detectingdeviceandawindingdevice capable o f d e t e c t i n g a p l u r a l i t y
ofyarndefectseachhavingalengthequaltoorlargerthanareference
length c o l l e c t i v e l y a s one d e f e c t .
30 A yarn d e f e c t d e t e c t i n g device of t h e present invention
includes: a yarn t h i c k n e s s d e t e c t i n g s e c t i o n t h a t d e t e c t s a t h i c k n e s s
of a t r a v e l i n g yarn; a y a r n d e f e c t determining s e c t i o n t h a t determines
whether a p a r t of t h e yarn d e t e c t e d by t h e yarn t h i c k n e s s d e t e c t i n g
s e c t i o n and having a t h i c k n e s s f a l l i n g o u t s i d e a t h i c k n e s s t h r e s h o l d
35 s p e c i f i e d a s a determination t h r e s h o l d of a d e f e c t of t h e yarn has
(D a length equal to or larger than a reference length specified as the
determination threshold and determines, when the part of the yarn
having the thickness falling outside the thickness threshold
specified as the determination threshold has a length equal to or
5 largerthanthe reference length, the part ofthe yarn falling outside
the thickness threshold specified as the determination threshold as
a defect; and an end point identifying section that identifies an
end point of the defect in a longitudinal direction when the part
is determined as the defect by the yarn defect determining section.
10
B R I E F DESCRIPTION OF THE DRAWINGS
F I G . 1is a frontviewofa yarnwinding unit serving as awinding
device according to an embodiment of the present invention;
F I G . 2 is a side view of the yarn winding unit according
15 to the embodiment of the present invention;
F I G . 3 is an example of a block configuration diagram of
a unit controller;
F I G . 4 i s a n o t h e r e x a m p l e o f a b l o c k c o n f i g u r a t i o n d i a g r a m
of a unit controller;
20 F I G S . 5A and 5B are each a schematic view illustrating
a reference length and a defect length at a detection time of a yarn
defect;
F I G S . 6A and 6B are each a schematic view illustrating
a length of a normal part and a defect length at the yarn defect
25 detection time;
F I G . 7 is a graph illustrating a temporal change of a yarn
thickness;
F I G . 8 is a table illustrating a type of the yarn defect;
and
30 F I G . 9 is a flowchart illustrating a procedure of
processing to be performed by a control section.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
As illustrated in F I G S . 1 and 2, a yarn winding unit 1 is a unit
35 that winds a yarn Y into a package P . For example, a plurality of
the yarn winding units 1 are arranged in parallel to each other to
constitute an automatic winder. The yarn winding unit 1 includes,
sequentially from an upstream side (lower side, in F I G . 1) along a
travelingpath (i.e., yarnpassage) ofthe yarn Y, a bobbin supporting
section 2 serving as a yarn supplying section, a yarn unwinding
assistingdevice 3, apre-clearer 4, a gate type tension controlmember
5, a tension sensor 6, a lower yarn catching device 7, a splicer 8
(yarn joining device), a cutter 9 (yarn cutting section), a yarn
c l e a r e r l O ( y a r n d e f e c t d e t e c t i n g d e v i c e ) capableofdetectingadefect
of the yarn Y, an upper yarn catching device 11 (winding side yarn
catching section), and a yarn winding section 12. Each of the above
components is attachedto a frame 13. The yarnwinding unit 1 further
includes a unit controller (control section) 14 and a display 15
serving as a notifying section.
The bobbin supporting section 2 is a section that supplies a
yarn and supports a yarn supplying bobbin B in an upright state. The
yarn supplying bobbin B is formed by a fine spinning machine in a
pre-stepandis transported fromthe fine spinningmachinewhilebeing
set in a tray, for example. The yarn unwinding assisting device 3
controls aballoonofthe yarnyunwound fromtheyarn supplyingbobbin
B by a tubular member arranged above the yarn supplying bobbin B.
Thegate type tensioncontrolmember 5 applies apredeterminedtension
on the travelling yarn Y by holding the yarn Y in a zigzag form with
a pair of gates including a fixed gate and a movable gate of comb
teeth shape. The tension sensor 6 measures a tension of the yarn Y
traveling along the yarn passage. The unit controller 14
feedback-controls the gate-type tension control member 5 such that
a predetermined tension is applied to the traveling yarn Y based on
the tension of the yarn Y measured by the tension sensor 6.
The pre-clearer 4 regulates in advance passing of the yarn
defect greater than a defined value by a pair of regulating members
arranged at a predetermined interval with a yarn passage interposed
therebetween.
The yarn clearer 10 detects the yarn defect such as "Slub" (see
F I G . 8) during winding of the yarn Y. As illustrated in F I G . 3, the
yarn clearer 10 includes a clearer head 51 (yarn thickness detecting
section) that detects a thickness of the yarn Y passing therethrough
and an analyzer 52 (details of which will be described later) that
determines presence/absence of the defect of the yarn Y based on the
thickness of the yarn Y detected by the clearer head 51. The yarn
clearer 10 may detect a yarn traveling speed of the yarn Y traveling
between the bobbin supporting section 2 and yarn winding section 12.
The cutter 9 cuts the yarn Y upon issuance of a yarn joining
instruction from the unit controller 14 after the yarn clearer 10
detects the yarn defect. The splicer 8 joins a yarn end on the yarn
supplying bobbin B side and yarn end on the package P side when the
yarn Y is cut by the cutter 9 or when the yarn Y is disconnected.
The lower yarn catching device 7 is configured to be vertically
swingable about an axis line a, where a suction port 7a is arranged
at a swinging end thereof. The suction port 7a is swung between an
upper part of the splicer 8 and a lower part of the pre-clearer 4.
The upper yarn catching device 11 is configured to be vertically
swingable about an axis center P, where a suction port lla is arranged
at a swinging end thereof. The suction port lla is swung between a
lower part of the splicer 8 and the yarn winding section 12. With
the above configuration, the lower yarn catching device 7 is swung
inadownwarddirection soas to suckthe yarnendonthe yarn supplying
bobbin B side with the suction port 7a, and thereafter, swung in an
upward direction to pass the yarn end on the yarn supplying bobbin
B side to the splicer 8. On the other hand, the upper yarn catching
device I1 is swung in an upward direction to suck the yarn end on
the package P side with the suction port lla, and thereafter, swung
in a downward direction to pass the yarn end on the package P side
to the splicer 8.
The yarn winding section 12 winds the yarn Y unwound from the
yarn supplying bobbin B into the package P to form a fully-wound
package P while performing traversing to reciprocate the yarn in a
left-right direction (in an axial direction of a winding drum 16).
The yarn winding section 12 includes a winding drum 16 and a cradle
17 serving as a supporting mechanism.
The winding drum 16 r o t a t e s t h e package P while making contact
with t h e package P t o wind t h e yarn Y i n t o t h e package P. The winding
drum 16 has, formed t h e r e i n , a drum grove 16a f o r t h e t r a v e r s i n g .
The winding drum 16 is a t t a c h e d with a r o t a t i o n sensor 31. The
r o t a t i o n sensor 3 1 i s e l e c t r i c a l l y connected t o t h e analyzer 52, etc.,
o f t h e y a r n c l e a r e r 10. T h e r o t a t i o n s e n s o r 3 1 i s c o n f i g u r e d a s , e - g . ,
a r o t a r y encoder and t r a n s m i t s a pulse s i g n a l t o t h e analyzer 52 every
t i m e t h e winding drum 16 is r o t a t e d a t a predetermined angle. The
pulse s i g n a l output from t h e r o t a t i o n sensor 31 is r e f e r r e d t o a s
a r o t a t i o n pulse s i g n a l .
A c r a d l e 17 r o t a t a b l y supports t h e package P. As t h e package
PI a cone-shaped package, a p i l l a r - s h a p e d package, o r t h e l i k e may
be used. The c r a d l e 17 can c o n t r o l an angle formed by an a x i a l l i n e
of t h e winding drum 16 and a x i a l l i n e of t h e package P. The c o n t r o l
of t h e angle a l l o w s a p o s i t i o n of a contact p o i n t ( h e r e i n a f t e r ,
r e f e r r e d t o a s " d r i v i n g p o i n t " ) betweenthewindingdrum16andpackage
P t o be c o n t r o l l e d . Further, t h e c r a d l e 17 b r i n g s a s u r f a c e of t h e
package P i n t o contact w i t h a s u r f a c e of t h e winding drum 16 with
an a p p r o p r i a t e c o n t a c t p r e s s u r e . The winding drum 16 is driven and
r o t a t e d by a motor t o r o t a t e t h e package PI whereby t h e yarn winding
s e c t i o n 12 winds t h e yarn Y i n t o t h e package P while t r a v e r s i n g t h e
yarn Y a t a predetermined width. An o u t e r circumference s u r f a c e of
t h e w i n d i n g d r u m 1 6 a n d a n o u t e r c i r c u m f e r e n t i a l s u r f a c e o f t h e p a c k a g e
P make contact with each o t h e r a t t h e d r i v i n g p o i n t , whereby a r o t a r y
d r i v i n g f o r c e of t h e winding drum 16 is t r a n s m i t t e d t o t h e package
P.
The u n i t c o n t r o l l e r 1 4 c o n t r o l s each of t h e components
c o n s t i t u t i n g t h e yarnwinding u n i t 1. Theunit c o n t r o l l e r 1 4 includes
a CPU ( C e n t r a l Processing Unit) t h a t performs computations, and a
ROM (Read Only Memory) and a RAM (Random Access Memory) each of which
serve a s a s t o r a g e s e c t i o n . The u n i t c o n t r o l l e r 1 4 r e c e i v e s , from
e a c h o f t h e components o f t h e yarnwinding u n i t 1, information required
f o r c o n t r o l o p e r a t i o n .
When t h e automatic winder is c o n s t i t u t e d by a p l u r a l i t y of t h e
yarn winding u n i t s 1, t h e u n i t c o n t r o l l e r 1 4 exchanges various
information concerning winding o p e r a t i o n w i t h a c o n t r o l l e r t h a t
c o n t r o l s t h e e n t i r e o p e r a t i o n of t h e automatic winder. The u n i t
c o n t r o l l e r 1 4 is e l e c t r i c a l l y connected t o t h e yarn c l e a r e r 10,
r o t a t i o n sensor 31, d i s p l a y 15, s p l i c e r 8, lower yarn catching device
7, and upper yarn catching device 11.
The d i s p l a y 15 d i s p l a y s o p e r a t i n g c o n d i t i o n s and t h e l i k e of
t h e yarn winding u n i t 1. When t h e yarn d e f e c t is d e t e c t e d by t h e yarn
c l e a r e r 10, t h e d i s p l a y 15 may d i s p l a y t h e d e t e c t i o n of t h e yarn
d e f e c t .
Next, a d e s c r i p t i o n w i l l be made on t h e yarn c l e a r e r 10 with
r e f e r e n c e t o FIG. 3. The analyzer 52 of t h e yarn c l e a r e r 10 includes
a CPU 27 t h a t performs computations and a ROM/RAM serving as a storage
s e c t i o n 28. The analyzer 52 includes a s a processing s e c t i o n , an end
p o i n t i d e n t i f y i n g s e c t i o n 21, a y a r n d e f e c t determining s e c t i o n 22,
a d e f e c t l e n g t h m e a s u r i n g s e c t i o n (measuring s e c t i o n ) 23, anda defect
removal i n s t r u c t i n g s e c t i o n 24. In t h e analyzer 52, a program s t o r e d
i n t h e ROM is loaded onto t h e RAM and executed by t h e CPU, whereby
e a c h o f t h e p r o c e s s i n g s e c t i o n s i s i m p l e m e n t e d a s software. However,
each o f t h e processing s e c t i o n s may be implemented a s hardware.
Further, a s i l l u s t r a t e d i n FIG. 4, t h e analyzer 52 may be i n s t a l l e d
i n t h e frame 13.
The yarn d e f e c t determining s e c t i o n 22 acquires information
concerning t h e t h i c k n e s s of t h e yarn Y from t h e c l e a r e r head 51 and
determines whether t h e r e is any d e f e c t of t h e yarn Y.
The yarn d e f e c t determining s e c t i o n 22 may include a t y p e
determining s e c t i o n t h a t determines a type of t h e d e f e c t of t h e yarn
Y and determine whether t o measure a length of t h e d e f e c t depending
o n t h e d e f e c t type. The y a r n d e f e c t determining s e c t i o n 2 2 determines
t h e d e f e c t type based on t h e information concerning t o t h e yarn
t h i c k n e s s .
FIG. 8 is a t a b l e i l l u s t r a t i n g t h e t y p e ( d e t e r m i n a t i o n
t h r e s h o l d ) o f t h e y a r n d e f e c t . T h e d e f e c t t y p e i n c l u d e s , e . g . , "Nep",
"Slub", "Thick place", "Thin place", and t h e l i k e . When d e t e c t i n g
a t h i c k n e s s l a r g e r b y 2 0 0 % o r m o r e t h a n a n a v e r a g e t h i c k n e s s ( r e f e r e n c e
t h i c k n e s s ) of t h e yarn Y, t h e yarn d e f e c t determining s e c t i o n 22
determines that the defect type is the "Nep". Then, the yarn defect
determiningsection22 executes removal ofthe yarndefect immediately
without considering the defect length.
The "Nep" is a knot of entangled thin fibers. For example, the
"Nep" occurs when a fiber aggregation exists in a spun fiber bundle.
Sucha defect is comparativelysmallinlength. In general, the "Nep"
is about 5 mm in length.
When detecting a thickness larger by 150% or more and less than
200% than the average thickness, the yarn defect determining section
22 determines that the defect type is the "Slub". Then, the yarn
defect determining section 22 executes removal of the yarn defect
immediately without measuring the defect length.
The "Slub" is a state where a yarn has an abnormal thickness
compared to the other part and has little twist. This is caused by
presenceofadefectpartorimpuritiesinthespunyarn. Suchadefect
is comparatively small in length. In general, the "Nep" is about 10
mm to 30 mm in length.
When detecting a thickness larger by 110% or more and less than
150% than the average thickness, the yarn defect determining section
22 determines that the defect type is the "Thick place". Then, the
yarn defect determining section 22 determines to measure the defect
length. When determining that the defect type is the "Thick place",
the yarn defect determining section 22 determines that the defect
length is equal to or larger than the reference length.
The "Thick place" is a state where a thick part in a sliver,
from which the yarn is to be spun by a spinning machine, is spun as
a yarn. Such a defect is likely to be large in length since the thick
part of the sliver is extended by the spinning machine. The "thick
part" may have a length of 30 m or more.
When detecting a thickness smaller by 90% or less than the
average thickness, the yarn defect determining section 22 determines
that the defect type is the "Thin place". Then, the yarn defect
determining section 22 determines tomeasure the defect length. When
determining that the defect type is the "Thin place", the yarn defect
determining section 22 determines that the defect length is equal
to or larger than the reference length.
The "Thin place" is a state where a thin part in a sliver, from
which the yarn is to be spun by a spinning machine, is spun as a yarn.
Such a defect is likely to be large in length. The "thin part" may
have a length of 30 m or more.
The yarn defect determining section 22 determines a thickness
unevenness of the yarn based on a determination threshold set with
respect to a reference length L1 (see F I G . 5) of the defect of the
yarn Y. When a yarn meeting the detection condition of the "Thick
place" or "Thin place" has a length equal to or larger than the
reference length L1, the yarn defect determining section 22 detects
an occurrence of a defect corresponding to a yarn unevenness
corresponding tothe "Thickplace" or "Thin place" and then determines
to measure the defect length. The determination threshold set with
respect to the reference length L1 is stored in, e.g., the storage
section 28.
The defect length measuring section 23 measures the defect
length based on the defect determined by the yarn defect determining
section 22 and an end point of the thickness unevenness identified
by the end point identifying section 21.
F I G . 5A illustrates a case where a defect having a length equal
to or larger than the reference length L1 exists in the yarn Y. The
clearer head 51 detects an occurrence of the thickness unevenness
(a part of the yarn having a thickness falling outside the thickness
threshold specified as the determination threshold) of the yarn Y.
The yarn defect determining section 22 determines whether the length
of the thickness unevenness of the yarn is equal to or larger than
the reference length L1 based on information on the thickness of the
yarn Y. In F I G S . 5 and 6, an area where the thickness unevenness of
the yarn exists is indicated by hatching.
In the example of F I G . 5A, the thickness unevenness exceeds the
reference length L1 and, accordingly, the yarn defect determining
section22 determinesthe occurrenceofthedefect andthendetermines
to measure the defect length to the end point of the thickness
unevenness. The end point identifying section 21 identifies the end
point of t h e d e f e c t i n a l o n g i t u d i n a l d i r e c t i o n based on t h e
information on t h e t h i c k n e s s of t h e yarn Y. Then, t h e d e f e c t length
measuring s e c t i o n 23 measures a l e n g t h L2 of t h e d e f e c t .
In t h e example of FIG. 5B, t h e t h i c k n e s s unevenness (having a
5 t h i c k n e s s l a r g e r by 110% o r more and less than 150% than t h e average
t h i c k n e s s ) corresponding t o t h e "Thick place" has a l e n g t h s m a l l e r
t h a n t h e r e f e r e n c e l e n g t h L 1 i n t h e yarnY. I n t h i s case, t h e t h i c k n e s s
unevenness does not exceed t h e r e f e r e n c e l e n g t h L1, so t h a t t h e yarn
d e f e c t d e t e r m i n i n g s e c t i o n 2 2 o f t h e y a r n c l e a r e r 1 0 d o e s n o t r e c o g n i z e
10 t h i s t h i c k n e s s unevenness a s t h e d e f e c t .
A s t a r t p o i n t of t h e d e f e c t t o be used i n t h e measurement of
t h e d e f e c t l e n g t h L 2 m a y b e a p o i n t a t w h i c h t h e y a r n d e f e c t d e t e r m i n i n g
s e c t i o n 22 d e t e r m i n e s t h a t t h e d e f e c t meeting t h e d e t e c t i o n c o n d i t i o n
e x i s t s o r a p o i n t a t which an a c t u a l t h i c k n e s s unevenness s t a r t s .
15 The end p o i n t of t h e d e f e c t may be a p o i n t a t which it is determined
t h a t t h e t h i c k n e s s unevenness meeting t h e d e t e c t i o n c o n d i t i o n dos
not e x i s t s o r a p o i n t a t which t h e a c t u a l t h i c k n e s s unevenness ends.
The d e f e c t length can be c a l c u l a t e d based on a t r a v e l i n g speed
of t h e yarn Y and a t i m e e l a p s i n g before d e t e c t i o n of t h e end point
20 of t h e t h i c k n e s s unevenness. The t r a v e l i n g speed of t h e yarn Y may
be c a l c u l a t e d based on information from t h e c l e a r e r head 51, based
on t h e r o t a t i o n pulse s i g n a l from t h e r o t a t i o n sensor 31, o r based
on a s i g n a l from a n o t h e r s e n s o r .
The d e f e c t l e n g t h measuring s e c t i o n 23 may i n c l u d e a normal
25 length measuring s e c t i o n t h a t measures, a f t e r t h e end point
i d e n t i f y i n g s e c t i o n 21 i d e n t i f i e s t h e end point of t h e d e f e c t ( f i r s t
d e f e c t ) , a l e n g t h of a normal p a r t L4 (see FIG. 6) having a t h i c k n e s s
fallingwithinthethicknessthresholdspecifiedasthedetermination
t h r e s h o l d . When t h e length of t h e normal p a r t is s m a l l e r t h a n a
30 predetermined value, t h e e n d p o i n t i d e n t i f y i n g s e c t i o n 2 1 i d e n t i f i e s
t h e end point of t h e d e f e c t once again a f t e r passing of t h e normal
p o i n t , and t h e normal l e n g t h measuring s e c t i o n measures t h e f i r s t
and second d e f e c t s a s one continuous d e f e c t . When d e t e c t i n g t h e
length of t h e normal p a r t t h a t is smaller than a predetermined value,
35 t h e normal length measuring s e c t i o n d e t e c t s t h e end p o i n t of t h e
@ subsequently detected thick unevenness of the yarn after passing of
the normal point, and measures the length as one continuous defect.
FIG. 6A illustrates a case where a defect corresponding to the
"Thick place" or "Thin place" having a length equal to or larger than
5 the reference length L1 exists in the yarn Y and where the length
L4 of the normal part is smaller than a predetermined value. After
detection of the end point of the thickness unevenness of the yarn,
the defect length measuring section 23 measures the length L4 of the
normal part where the thickness unevenness has not been detected.
10 T h e d e f e c t l e n g t h m e a s u r i n g s e c t i o n 2 3 referstoapredeterminedvalue
stored in the storage section 28 and determines whether the length
L4 of the normal part is smaller or not than the predetermined value.
In the example of FIG. 6A, the length L4 of the normal part is smaller
than the predetermined value, so that, after passing of the normal
15 part, the end point identifying section 21 identifies the end point
of the subsequently detected thickness unevenness of the yarn once
again, and the defect length measuring section 23 measures a length
L5 of the defect.
FIG. 6B illustrates a case where a defect corresponding to the
20 "Thick place" or "Thin place" having a length equal to or larger than
the reference length L1 exists in the yarn Y and where a length L6
of the normal part is larger than the predetermined value. In the
example of FIG. 6B, the length L6 of the normal part is equal to or
larger than the predetermined value, so that the defect length
25 measuring section 23 measures a length L7 of the defect.
The predetermined value for use in determination of the length
of the normal part may be a fixed value or may be changed according
to, e.g., the length L7 of the defect immediately before the normal
part. The predetermined value may be set to, e. g., 10% of the length
30 L7 of the defect immediately before the normal part.
The yarn defect determining section 22 may detect the defect
based on a first detection condition and detect the end point of the
defect based on a second detection condition different from the first
detectioncondition. FIG. 7 is agraphillustratingatemporalchange
35 of the thickness of the yarn Y. In FIG. 7, a vertical axis represents
the thickness ofthe yarnYanda horizontal axis represents anelapsed
time. A curve K in FIG. 7 represents the thickness of the yarn Y,
which becomes thicker as it goes upward and becomes thinner as it
goes downward.
When a first detection condition G1 is met, the yarn defect
determining section 22 determines that the thickness unevenness
exists in the yarn Y. More specifically, the yarn defect determining
section 22 determines that the thickness unevenness exists when the
curve K is above the first detection condition G1 in Fig. 7.
When a second detection condition G2 is met, the end point
identifying section 21 determines that the end point of the thickness
unevenness ofthe yarnY has beenidentified. More specifically, the
end point identifying section 21 determines that the thickness
unevenness does not exist when the curve K is below the second
detection condition G2 in Fig. 7. Thus, the thickness unevenness of
theyarnendsis finished, andtheendpointofthedefectisidentified.
The defect length measuring section 23 measures the length L2 of the
defect based on the end point of the thickness unevenness of the yarn
identified by the end point identifying section 21.
In the example of FIG. 7, after the curve K exceeds the first
detection condition G1 (that is, after it is determined that a defect
in which the thickness of the yarn is larger than the detection
condition of "Thick place" exists), the curve K has parts C1 and C2
each having a thickness equal to or smaller than the first detection
condition GI and a thickness equal to or larger than the second
detection condition G2. In the present embodiment, the thickness
unevenness of the yarn is not determined to end until the thickness
becomes equal to or smaller than the second detection condition G2,
so that, in this case, the length L2 is detected as one continuous
defect. Thus, it is possible to reduce the number of times of removal
of the defect. The first and second detection conditions G1 and G2
to be set in the end point identifying section 21 and yarn defect
determining section 22 may have the same thickness value.
The defect removal instructing section 24 instructs removal of
the yarn as the defect when the length of the thickness unevenness
a! of the yarn is measured and the thickness unevenness of the measured
yarn is equal to or larger than the specified length. The defect
removal instructing section 24 transmits, to the unit controller 14,
an instruction signal instructing removal of the yarn by a set amount
5 when the yarn defect determining section 22 detects the yarn defect
as the "Slub" of "Nep" and determines not to consider the length of
the defect.
T h e d e f e c t r e m o v a l i n s t r u c t i n g s e c t i o n 2 4 oftheunit controller
14 instructs the yarn winding section 12 to stop winding of the yarn
10 Y. The yarn Y is cut by the cutter 9, and the yarn end on the yarn
supplying bobbin B side is sucked to the suction port 7a of the lower
yarn catching device 7, and the package P side end of the yarn the
including the yarn defect is sucked to the suction port lla of the
u p p e r y a r n c a t c h i n g d e v i c e l l . At this time, inacasewhere the length
15 of the defect has been measured, the upper yarn catching device 11
sucks the yarn Y in accordance with the measured defect length. In
a case where the length of the defect has not been measured, the upper
yarn catching device 11 sucks the yarn Y by a previously set length.
For example, it is possible to provide, in the suction port lla, a
20 sensor capable of detecting the length of the yarn Y passing
therethrough and to measure the length of the sucked yarn Y using
this sensor. Alternatively, it ispossibletoprovide a simple ON/OFF
sensor in the suction port lla and to reverse-rotate the winding drum
16bya rotationangle corresponding tothe lengthofthe yarn Y sucked
1 I 25 when the sensor turns ON by detecting the yarn end to feed the yarn i Y. Another method may be used to measure the length of the sucked
I
yarn Y.
I The upper yarn catching device 11 passes the package P side end
I
1 of the sucked yarn Y to the splicer 8. The lower yarn catching device
I
I 30 7 passes the yarn supplying bobbin B side end of the sucked yarn Y
to the splicer 8. The yarn end on the package P side and yarn end
I on the yarn supplying bobbin B side are joined by the splicer 8. In
I
the yarn joining, the yarn Y including the sucked defect is cut for
removal. That is, the lower yarn catching device 7, splicer 8, and
35 upper yarn catching device 11 constitute a defect removing section. I
After the yarn joining, thewindingdrum16is drivento resume winding
of the yarn Y.
Next, a description will be made on processing to be performed
by the analyzer 52 of the yarn clearer 10 with reference to FIG. 9.
The yarn defect determining section 22 of the analyzer 52
determines whether to have detected the thickness unevenness of the
yarn (step S1) . The yarn defect determining section 22 determines
to have detected the thickness unevenness of the yarn based on the
information indicating the thickness of the yarn Y input from the
clearer head 51. When determining that the thickness of the yarn Y
meets the detection condition based on the defect determination
threshold, the yarn defect determining section 22 determines to start
detection of the yarn defect (YES in step Sl), and the processing
flow proceeds to step S2. When determining that the thickness of the
yarn Y does not meet the detection condition as illustrated in FIG.
5B, the yarn defect determining section 22 determines not to detect
the yarn defect (NO in step S1) and continues the processing of step
S1.
In step S2, the yarn defect determining section 22 of the
analyzer 52 determines whether to consider the length of the defect
(step S2). When the thickness unevenness of the yarn meeting the
detection condition of the "Thick place" or "Thin place" exceeds the
reference length L1 as illustrated in FIG. 5A, the yarn defect
determining section 22 determines to consider the length ofthe defect
(YES in step S2), and the processing flow proceeds to step S3. When
detecting that the thickness unevenness of the yarn meeting the
detection condition of the "Nep" or "Slub", the yarn defect
determiningsection22 recognizes anoccurrenceofthe "Nep"orWSlub"
and determines not to consider the length of the defect (NO in step
S2), and the processing flow proceeds to step S5.
In step S3, the defect length measuring section 23 of the
analyzer 52 measures the length L2 of the defect until identification
oftheendpoint ofthe thickness unevenness ofthe yarnas illustrated
in FIG. 5A, and the processing flow proceeds to step S4.
In step S4, the defect removal instructing section 24 of the
unit controller 14 sets the length of the measured defect as a length
of the yarn to be removed, and the processing flow proceeds to step
S6.
In step S5, the defect removal instructing section 24 of the
unit controller 14 sets a preset length as the length of the yarn
to be removed, and the processing flow proceeds to step S6.
In step S6, the defect removal instructing section 24 of the
unit controller 14 instructs removal of the defect, and this routine
ends.
The yarn winding unit 1 of the present embodiment includes the
yarn clearer 10 as the yarn defect detecting device, by which when
the thickness unevenness ofthe yarnhavingalengthequaltoorlarger
than the reference length L1 is detected, the length of the defect
is measured. According to the yarn winding unit 1, it is possible
to detect a plurality of defects collectively as one defect longer
than in the conventional approach. The yarn winding unit 1 can
determine the length of the yarn to be removed based on the length
of the detected defect, thereby eliminating the need to perform a
plurality of times of removal operations as done in the conventional
approach. This allows improvement in production efficiency and
prevention of quality deterioration.
Although the embodiment of the present invention has been
described, the present invention is not limited to the above
embodiment. For example, in the above embodiment, the yarn Y is
traversedontothesurfaceofthepackagebeingrotatedbytherotating
winding drum 16. However, the present invention is not limited to
thisbut maybe appliedto ayarnwindingdevicehavinga configuration
in which drive of the package and traversing are performed
independently of each other. An example of such yarn winding device
includes, e.g., anautomaticwinderprovidedwithanarm-type traverse
device that traverses the yarn Y with a swinging arm or a belt-type
traverse device that traverses the yarn Y with a yarn hooking member
that reciprocates to the left and the right by a belt.
The yarn defect detecting device of the present invention may
be applied not only to the automatic winder but also to another type
Q of a yarn processing device such as a fine spinning machine.
The yarn defect detecting device of the present invention may
be incorporated in the yarn clearer 10 or unit controller 14, or may
be configured as an independent device.
5 Theyarndefectdetectingdevice furtherincludesa yarncutting
section that cuts the yarn when the end point identifying section
identifies the longitudinal direction end point of the defect.
In the yarn defect detecting device, when a part of the yarn
having a thickness falling outside a thickness threshold specified
10 as a determination threshold has a length equal to or larger than
a reference length specified as the determination threshold, an end
point of a defect in a longitudinal direction is identified. Thus,
it is possible to detect a plurality of defects collectively as one
defect longer than in the conventional approach. For example, a
15 length of the yarn to be removed can be determined based on the length
of the part of the yarn having the thickness falling outside the
t h i c k n e s s t h r e s h o l d s p e c i f i e d a s t h e d e t e r m i n a t i o n t h r e s h o l d , t h e r e b y
eliminating the need to perform a plurality of times of removal
operations as done in the conventional approach. This allows
20 improvement in production efficiency and prevention of quality
deterioration. When a required quality level is high, it can be
estimated that the length of the defect to be detected is larger.
It is possible to detect a plurality of defects collectively as one
long defect, thereby allowing achievement of a high quality yarn
25 product.
T h e y a r n d e f e c t d e t e c t i n g d e v i c e m a y i n c l u d e a m e a s u r i n g s e c t i o n
that measures the length of the defect. Measuring the length of the
defect allows collective detection of a long defect, thereby allowing
achievement of a high quality yarn product.
30 The yarndefect determining sectionmaydetermine anoccurrence
of the defect based on a first detection condition, and the end point
identifying section may determine the end point of the defect based
on a second detection condition different from the first detection
condition. With this configuration, detection of the defect can be
35 detected by determining presence/absence of the defect based on the
first detection condition, and the end point of the defect can be
detected based on the second detection condition. For example,
settingthe seconddetectioncondition that is stricterthanthe first
condition results in measurement of longer defect, thereby ensuring
margin of detection error.
The yarn defect determining section may include a type
determining section that determines a type of the yarn defect, and
the end point identifying section may determine whether to identify
the end point of the defect depending on the defect type. The yarn
defect type includes "Nep", "Slub", "Thick place", "Thin place", and
the like. The defect such as "Nep" or "Slub" is comparatively small
in length and is thus preferably removed without measurement of the
lengthofthedefect. Thedefect suchas "Thickplace"or"Thinp1ace"
may be generated by unevenness of a sliver as a material during fine
spinning and may thus be large in length. The length of the defect
is measured only for the defect comparatively large in length and
whereby defect removal corresponding to the defect length can be
performed.
The measuring section may include a normal length measuring
section that measures a length of a normal part of the yarn having
a thickness falling within the thickness threshold specified as the
determination threshold. The end point identifying section may
identify, when the length of the normal part following the part of
the yarn determined by the yarn defect determining section as the
defect is equal to or larger than a predetermined length, the end
point of the defect. Further, when the yarn sequentially includes
the part determined by the yarn defect determining section as the
defect, a normal part having a length equal to or smaller than a
predeterminedlength, and another defect part, the measuring section
may measure the lengths of the two defect parts and normal part as
one continuous defect. Thus, a comparativelylongdefect is detected.
Further, when the length of the normal part following the defect is
short, it is possible to collectively measure a plurality of defects
as one continuous defect. This reducesthenumber of times of removal
of the defect, allowing improvement in production efficiency and
product q u a l i t y .
The yarn d e f e c t d e t e c t i n g device may f u r t h e r i n c l u d e a c o n t r o l
s e c t i o n t h a t c o n t r o l s removal of t h e d e f e c t . A f t e r t h e measuring
s e c t i o n measures t h e length of t h e d e f e c t , t h e c o n t r o l s e c t i o n may
i n s t r u c t removal of a yarn by a l e n g t h equal t o o r l a r g e r than t h a t
o f t h e m e a s u r e d d e f e c t . With t h i s c o n f i g u r a t i o n , when t h e d e f e c t has
a l e n g t h s m a l l e r t h a n t h e r e f e r e n c e length, t h e yarn is removed by
a previously set length; while when t h e d e f e c t has a length equal
t o o r l a r g e r than t h e r e f e r e n c e length, t h e yarn is removed i n
accordance with a measured d e f e c t l e n g t h .
A winding device of t h e present invention i n c l u d e s : t h e yarn
d e f e c t d e t e c t i n g d e v i c e d e s c r i b e d above; a yarn winding s e c t i o n t h a t
winds a yarn t h a t has passed through t h e yarn d e f e c t d e t e c t i n g device;
and a d e f e c t removing s e c t i o n t h a t removes a d e f e c t of t h e yarn
d e t e c t e d by t h e yarn d e f e c t d e t e c t i n g device.
Theyarnwindingunitincludestheyarndefectdetectingdevice,
by which when t h e d e f e c t o f t h e yarn having a l e n g t h equal t o o r l a r g e r
than t h e r e f e r e n c e l e n g t h is d e t e c t e d , t h e length of t h e d e f e c t is
measured. Thus, it is p o s s i b l e t o d e t e c t a p l u r a l i t y of d e f e c t s
c o l l e c t i v e l y a s one d e f e c t l o n g e r t h a n i n t h e conventional approach.
Theyarnwindingunitcandeterminethelengthoftheyarntoberemoved
based on t h e length of t h e d e t e c t e d d e f e c t , thereby e l i m i n a t i n g t h e
need t o perform a p l u r a l i t y of t i m e s of removal o p e r a t i o n s a s done
i n t h e conventional approach. This allows improvement i n production
e f f i c i e n c y and prevention of q u a l i t y d e t e r i o r a t i o n . When a required
q u a l i t y l e v e l is high, it can be estimated t h a t t h e l e n g t h of t h e
d e f e c t t o be d e t e c t e d is l a r g e r . The winding device can d e t e c t and
remove a p l u r a l i t y o f d e f e c t s c o l l e c t i v e l y a s one l o n g d e f e c t , thereby
allowing achievement of a high q u a l i t y yarn product.
According t o t h e present invention, it is p o s s i b l e t o d e t e c t
a p l u r a l i t y of yarn d e f e c t s each having a l e n g t h equal t o o r l a r g e r
than a r e f e r e n c e l e n g t h c o l l e c t i v e l y a s one d e f e c t .

WE CLAIM:
1. Ayarndefectdetectingdevice characterizedbycomprising:
a yarn thickness detecting section that detects a thickness of
5 a traveling yarn;
ayarndefectdetermining section that determines whether apart
oftheyarndetectedbytheyarnthicknessdetectingsectionandhaving
a thickness falling outside a thickness threshold specified as a
determination threshold of a defect of the yarn has a length equal
10 to or larger than a reference length specified as the determination
threshold and determines, when the part of the yarn having the
thickness falling outside the thickness threshold specified as the
determination threshold has a length equal to or larger than the
reference length, the part of the yarn falling outside the thickness
15 threshold specified as the determination threshold as a defect; and
an end point identifying section that identifies an end point
of the defect in a longitudinal direction when the part is determined
as the defect by the yarn defect determining section.
20 2 . The yarn defect detecting device according to claim 1,
further comprising a yarn cutting section that cuts the yarn when
the end point identifying section identifies the longitudinal
direction end point of the defect.
25 3 . The yarn defect detecting device according to claim 1 or
claim 2, comprising a measuring section that measures the length of
the defect.
4. The yarn defect detecting device according to claim 3,
30 wherein
the yarn defect determining section determines an occurrence
of the defect based on a first detection condition, and the end point
identifying section determines the end point of the defect based on
a second detection condition different from the first detection
35 condition.
5. The yarn defect detecting device according to any one of
claims 1 to 4, wherein
the yarn defect determining section includes atype determining
5 section that determines a type of the yarn defect, and
the end point identifying section determines whether to
identify the end point of the defect depending on the defect type.
6. The yarn defect detecting device according to any one of
10 claims 3 to 5, wherein
the measuring section includes a normal length measuring
section that measures a length of a normal part of the yarn having
a thickness falling within the thickness threshold specified as the
determination threshold, and
15 the end point identifying section identifies, when the length
of the normal part following the part of the yarn determined by the
yarn defect determining section as the defect is equal to or larger
I than a predetermined length, the end point of the defect.
20 7. The yarn defect detecting device according to any one of
claims 3 to 6, wherein
when the part determined by the yarn defect determining section
is determined as the defect, a normal part having a length equal to
or smallerthanapredeterminedlengthisincluded, andanother defect
25 part is determined, the measuring section measures the lengths of
the two defect parts and normal part as one continuous defect.
8. The yarn defect detecting device according to any one of
claims 3 to 7, further comprising a control section that controls
30 removal of the defect, wherein
after the measuring section measures the length of the defect,
the control section instructs removal of a yarn by a length equal
to or larger than that of the measured defect.
9. A winding device comprising:
t h e yarn d e f e c t d e t e c t i n g device a s c l a i m e d i n anyone of claims
1 t o 8;
a yarn winding s e c t i o n t h a t winds a yarn t h a t has passedthrough
t h e yarn d e f e c t d e t e c t i n g device; and
a d e f e c t removing s e c t i o n t h a t removes a d e f e c t of t h e yarn detected
by t h e yarn d e f e c t d e t e c t i n g device.
10. A yarn d e f e c t d e t e c t i n g device, s u b s t a n t i a l l y as herein
described with r e f e r e n c e t o accompanying drawings and examples.
11. A winding device, s u b s t a n t i a l l y a s h e r e i n described with
r e f e r e n c e t o accompanying drawings and examples.
Dated this llth day of July 2013
Of Anand and Anand Advocates
Agent for the Applicant