YARN MONITORING DEVICE AND YARN WINDING MACHINE
TECHNICAL FIELD
[0001] The present disclosure relates to a yarn monitoring device and a
5 yarn winding machine.
BACKGROUND
[0002] As a technique related to a yarn monitoring device, a yarn
clearer described in Japanese Patent No. 5413560 is known. The yarn
clearer described in Japanese Patent No. 5413560 measures light
10 (transmitted light) part of which has been blocked by spun yarn (yarn),
thereby detecting the thickness of the spun yarn. The yarn clearer
described in Japanese Patent No. 5413560 also measures reflected light
reflected by the spun yarn, thereby detecting a foreign substance
included in the spun yarn.
15 SUMMARY
[0003] While there are various types of yarn defects, it is difficult for a
yarn monitoring device as described above to distinguish types of such
yarn defects, and it may be difficult to accurately discriminate the yarn
defects.
20 [0004] In view of this, it is an object of the present disclosure to
provide a yarn monitoring device and a yarn winding machine that can
accurately discriminate yarn defects.
[0005] A yarn monitoring device according to one aspect of the present
disclosure is a yarn monitoring device configured to monitor yarn
25 traveling, and includes a discrimination section configured to
discriminate a type of a yarn defect of the yarn, based on a combination
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of thickness of the yarn and brightness of reflected light that has been
reflected by the yarn when the yarn has been irradiated with light.
[0006] In this yarn monitoring device, based on the combination of the
thickness of the yarn and the brightness of the reflected light reflected
5 by the yarn, the type of the yarn defect is discriminated. By this
configuration, a yarn defect that is difficult to be distinguished based
on only either one of the thickness and the brightness can be
distinguished, whereby the yarn defect can be accurately discriminated.
[0007] In the yarn monitoring device according to one aspect of the
10 present disclosure, the discrimination section may discriminate, as the
yarn defect, a first yarn defect having warpage, tangle, or entanglement
protruding in a direction intersecting a direction in which the yarn
travels. It is found that the first yarn defect (hereinafter, also called
"kink") having warpage, tangle, or entanglement protruding in a
15 direction intersecting the traveling direction of the yarn can be
discriminated by combining the thickness of the yarn and the
brightness of the reflected light reflected by the yarn. Thus, in the
present disclosure, a kink as the yarn defect can be accurately
discriminated.
20 [0008] In the yarn monitoring device according to one aspect of the
present disclosure, the discrimination section may discriminate, as the
yarn defect, a second yarn defect being a nep into which a foreign
substance is mixed. It is found that the second yarn defect
(hereinafter, also called "foreign-substance mixed nep") being a nep
25 into which a foreign substance is mixed can be discriminated by
combining the thickness of the yarn and the brightness of the reflected
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light reflected by the yarn. Thus, in the present disclosure, a
foreign-substance mixed nep as the yarn defect can be accurately
discriminated.
[0009] In the yarn monitoring device according to one aspect of the
5 present disclosure, the discrimination section may include a first
defect-discrimination-target identification section and a second
defect-discrimination-target identification section. The first
defect-discrimination-target identification section may identify, in a
first variation signal for thickness, a first defect-discrimination-target
10 portion for which a defect is to be assessed. The second
defect-discrimination-target identification section may identify, in a
second variation signal for brightness, a second
defect-discrimination-target portion for which a defect is to be
assessed. The discrimination section may identify the first
15 defect-discrimination-target portion and the second
defect-discrimination-target portion that correspond to each other in a
longitudinal direction of the yarn, and may discriminate the type of the
yarn defect based on the thickness of the first
defect-discrimination-target portion and the brightness of the second
20 defect-discrimination-target portion that have been identified as
portions corresponding to each other. By this configuration,
discrimination of the yarn defect based on the combination of the
thickness of the yarn and the brightness of the reflected light reflected
by the yarn can be specifically performed.
25 [0010] In the yarn monitoring device according to one aspect of the
present disclosure, the discrimination section may determine that a first
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yarn defect having warpage, tangle, or entanglement protruding in a
direction intersecting a direction in which the yarn travels is present
when the thickness of the first defect-discrimination-target portion is
equal to or greater than a first thickness criterion value and the
5 brightness of the second defect-discrimination-target portion is equal to
or higher than a first brightness criterion value. When the yarn defect
is a kink, it is found that a detected thickness increases to a certain
thickness or greater and also a detected brightness increases to a certain
brightness or higher because light is irregularly reflected by the kink.
10 Thus, according to the present disclosure, a kink can be more
accurately discriminated.
[0011] In the yarn monitoring device according to one aspect of the
present disclosure, the second defect-discrimination-target portion may
include a continuous portion in which the brightness is equal to or
15 higher than a threshold in the yarn, the continuous portion coinciding
with at least part of the first defect-discrimination-target portion. By
this configuration, discrimination of the yarn defect based on the
combination of the thickness of the yarn and the brightness of the
reflected light reflected by the yarn can be specifically performed.
20 [0012] In the yarn monitoring device according to one aspect of the
present disclosure, the discrimination section may determine that a
second yarn defect being a nep into which a foreign substance is mixed
is present when the thickness of the first defect-discrimination-target
portion is equal to or greater than a second thickness criterion value
25 and the brightness of the second defect-discrimination-target portion is
equal to or lower than a second brightness criterion value. When the
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yarn defect is a foreign-substance mixed nep, it is found that the
detected thickness increases to a certain thickness or greater and also
the detected brightness decreases to a certain brightness or lower
because light is absorbed by the foreign substance. Thus, according to
5 the present disclosure, a foreign-substance mixed nep can be more
accurately discriminated.
[0013] In the yarn monitoring device according to one aspect of the
present disclosure, the second defect-discrimination-target portion may
include a continuous portion in which the brightness is equal to or
10 lower than a threshold in the yarn, the continuous portion coinciding
with at least part of the first defect-discrimination-target portion. By
this configuration, discrimination of the yarn defect based on the
combination of the thickness of the yarn and the brightness of the
reflected light reflected by the yarn can be specifically performed.
15 [0014] In the yarn monitoring device according to one aspect of the
present disclosure, the discrimination section may determine the
presence or absence of a nep into which no foreign substance is mixed,
based on the length of a continuous portion in which the thickness is
equal to or greater than a threshold in the yarn and the thickness of the
20 continuous portion. By this configuration, the presence or absence of
a nep into which no foreign substance is mixed (hereinafter, also
simply called "nep") can be accurately determined.
[0015] In the yarn monitoring device according to one aspect of the
present disclosure, the discrimination section may determine the
25 presence or absence of mixing of a foreign substance, based on the
length of a continuous portion in which the brightness is equal to or
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lower than a threshold in the yarn and the brightness of the continuous
portion. By this configuration, the presence or absence of mixing of a
foreign substance can be accurately determined.
[0016] The yarn monitoring device according to one aspect of the
5 present disclosure may include: a light emitting element configured to
emit light toward a traveling region in which the yarn travels; a first
light receiving element disposed so as to receive light that has been
emitted from the light emitting element and part of which has been
blocked by the yarn; and a second light receiving element disposed so
10 as to receive light that has been emitted from the light emitting element
and has been reflected by the yarn, in which the thickness may be
calculated based on the amount of light received by the first light
receiving element, and the brightness may be calculated based on the
amount of light received by the second light receiving element. By
15 this configuration, the thickness of the yarn and the brightness of the
reflected light reflected by the yarn can be specifically calculated.
[0017] In the yarn monitoring device according to one aspect of the
present disclosure, the first defect-discrimination-target identification
section may identify the first defect-discrimination-target portion based
20 on the first variation signal and a first threshold, the second
defect-discrimination-target identification section may identify the
second defect-discrimination-target portion based on the second
variation signal and a second threshold, and the discrimination section
may identify the first defect-discrimination-target portion and the
25 second defect-discrimination-target portion overlapping each other in
the longitudinal direction of the yarn as the portions corresponding to
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each other. By this configuration, the first
defect-discrimination-target portion and the second
defect-discrimination-target portion can be accurately identified.
[0018] In the yarn monitoring device according to one aspect of the
5 present disclosure, the discrimination section may identify a peak
position of the first defect-discrimination-target portion, the
discrimination section may identify a peak position of the second
defect-discrimination-target portion, and the discrimination section
may identify, as the portions corresponding to each other, the first
10 defect-discrimination-target portion and the second
defect-discrimination-target portion the peak positions of which fall
within a predetermined range in the longitudinal direction. By this
configuration, the first defect-discrimination-target portion and the
second defect-discrimination-target portion can be accurately
15 identified.
[0019] The yarn monitoring device according to one aspect of the
present disclosure may further include a display section configured to
display a discrimination result of the discrimination section with a
scatter diagram axes of which represent the thickness and the
20 brightness. By this configuration, the discrimination result of the
discrimination section can be effectively displayed by using the scatter
diagram.
[0020] In the yarn monitoring device according to one aspect of the
present disclosure, the display section may display a first yarn defect
25 having warpage, tangle, or entanglement protruding in a direction
intersecting a direction in which the yarn travels so as to distinguish the
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first yarn defect from another yarn defect. In the yarn monitoring
device according to the present disclosure, the display section may
display a second yarn defect being a nep into which a foreign substance
is mixed so as to distinguish the second yarn defect from another yarn
5 defect.
[0021] A yarn winding machine according to one aspect of the present
disclosure includes: the yarn monitoring device described above; a yarn
feeder disposed so as to be able to feed the yarn; and a winding device
configured to wind the yarn fed from the yarn feeder to form a
10 package, in which the yarn monitoring device is disposed between the
yarn feeder and the winding device.
[0022] In this yarn winding machine also, the yarn monitoring device
described above is included, and thus the above-described effect, that
is, the effect of being able to accurately discriminate the yarn defect
15 can be obtained.
[0023] According to the present disclosure, the yarn monitoring device
and the yarn winding machine that can accurately discriminate the yarn
defect can be provided.
BRIEF DESCRIPTION OF THE DRAWINGS
20 [0024] FIG. 1 is a front view of a spinning machine according to an
embodiment.
[0025] FIG. 2 is a block diagram illustrating a configuration of a yarn
monitoring device in the spinning machine in FIG. 1.
[0026] FIG. 3 is a cross-sectional view illustrating one example of
25 physical components of a device body of the yarn monitoring device.
[0027] FIG. 4 is a graph for describing a method of calculating a defect
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thickness and a defect length.
[0028] FIG. 5 is a graph for describing determination of the presence or
absence of a nep.
[0029] FIG. 6A is an enlarged view exemplifying a kink, FIG. 6B is an
5 enlarged view exemplifying a kink, and FIG. 6C is an enlarged view
exemplifying a kink.
[0030] FIG. 7 is an enlarged photographic diagram exemplifying a
foreign-substance mixed nep.
[0031] FIG. 8A is a graph for describing discrimination of a kink and is
10 a graph representing the thickness and the length of yarn, and FIG. 8B
is a graph for describing discrimination of a kink and is a graph
representing the brightness and the length of the yarn.
[0032] FIG. 9A is a graph for describing discrimination of a
foreign-substance mixed nep and is a graph representing the thickness
15 and the length of the yarn, and FIG. 9B is a graph for describing
discrimination of the foreign-substance mixed nep and is a graph
representing the brightness and the length of the yarn.
[0033] FIG. 10 is a graph illustrating a scatter diagram as an example
of a discrimination result of a discrimination section.
20 [0034] FIG. 11 is a graph illustrating a scatter diagram as another
example of the discrimination result of the discrimination section.
[0035] FIG. 12 is a graph illustrating a scatter diagram as still another
example of the discrimination result of the discrimination section.
[0036] FIG. 13 is a front view of an automatic winder according to the
25 embodiment.
DETAILED DESCRIPTION
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[0037] An embodiment will now be described in detail with reference
to the drawings. In the drawings, like or equivalent elements are
designated by like numerals, and duplicate description is omitted.
[0038] As illustrated in FIG. 1, a spinning machine (yarn winding
5 machine) 1 includes a plurality of spinning units 2, a splicing carrier 3,
a doffing carrier (not illustrated), a first end frame 4, and a second end
frame 5. The spinning units 2 are aligned in a row. Each spinning
unit 2 forms yarn Y and winds the yarn Y into a package P. When
yarn Y has been cut or the yarn Y has broken for some reason in a
10 certain spinning unit 2, the splicing carrier 3 performs splicing
operation in the spinning unit 2. When a package P has been fully
wound in a certain spinning unit 2, the doffing carrier doffs the package
P, and supplies a new bobbin B to the spinning unit 2.
[0039] The first end frame 4 accommodates, for example, a collection
15 device configured to collect fiber waste, yarn waste, and the like
generated in the spinning unit 2. The second end frame 5
accommodates, for example, an air supply unit configured to adjust air
pressure of compressed air (air) supplied to the respective units in the
spinning machine 1 and supply the air to the respective units in the
20 spinning machine 1 and a drive motor configured to supply power to
the respective units in the spinning units 2. The second end frame 5
includes a machine control device 5a, a display 5b, and an input keys
5c. The machine control device 5a centrally manages and controls the
respective units of the spinning machine 1. The display 5b can
25 display, for example, information on at least one of settings and the
states of the spinning units 2. An operator can make the settings of
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the spinning units 2 by performing appropriate operations with the
input keys 5c.
[0040] Each spinning unit 2 includes, in the order from the upstream
side in a direction in which yarn Y travels, a drafting device 6, an air-jet
5 spinning device 7, a yarn monitoring device 8, a tension sensor 9, a
yarn storage device 11, a waxing device 12, and a winding device 13.
The unit controller 10 is provided for every predetermined number of
spinning units 2, and controls operations of the spinning units 2. In
each spinning unit 2, the drafting device 6 and the air-jet spinning
10 device 7 function as a yarn feeder configured to feed yarn Y.
[0041] The drafting device 6 drafts a sliver (fiber band) S. The air-jet
spinning device 7 forms yarn Y by twisting a fiber band F drafted by
the drafting device 6 using swirling airflow. The yarn storage device
11 eliminates slack in yarn Y between the air-jet spinning device 7 and
15 the winding device 13. The waxing device 12 applies wax to yarn Y
between the yarn storage device 11 and the winding device 13. The
winding device 13 winds yarn Y fed from the drafting device 6 and the
air-jet spinning device 7 that function as a yarn feeder around a bobbin
B to form a package P.
20 [0042] The yarn monitoring device 8 is a device configured to monitor
yarn Y traveling between the air-jet spinning device 7 and the yarn
storage device 11. The yarn monitoring device 8 detects the presence
or absence of a yarn defect on the basis of information on the
monitored yarn Y. When having detected a yarn defect, the yarn
25 monitoring device 8 transmits a yarn defect detection signal to the unit
controller 10. The tension sensor 9 measures the tension of traveling
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yarn Y between the air-jet spinning device 7 and the yarn storage
device 11, and transmits a tension measurement signal to the unit
controller 10. When the unit controller 10 determines that
abnormality has occurred based on at least one of the yarn defect
5 detection signal and the tension measurement signal, the yarn Y is cut
in the spinning unit 2.
[0043] FIG. 2 is a block diagram illustrating a configuration of the yarn
monitoring device 8. As illustrated in FIG. 2, the yarn monitoring
device 8 includes a device body 81, a discrimination section 82, and the
10 display 5b. The device body 81 includes a thickness detecting section
81a and a brightness detecting section 81b as functional components.
[0044] The thickness detecting section 81a is a section configured to
detect the thickness of traveling yarn Y. The thickness can be
expressed in terms of percentage when the reference yarn thickness that
15 is a reference thickness of yarn Y is assumed to be zero. Detection of
the thickness of yarn Y performed by the thickness detecting section
81a is detection of the apparent thickness of the yarn Y performed by
an optical method in the present embodiment, but may be detection of
the thickness of the yarn Y performed by a capacitive method. The
20 brightness detecting section 81b is a section configured to detect the
brightness of reflected light that has been reflected by yarn Y when the
yarn Y has been irradiated with light (hereinafter, also simply called
"brightness of yarn Y"). The brightness can be expressed in terms of
percentage when the reference yarn brightness that is a reference
25 brightness of yarn Y is assumed to be zero. For example, the
brightness of a pitch dark state (when light is blocked) can be
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expressed as -100%. The thickness detecting section 81a and the
brightness detecting section 81b constitute a detecting unit. The
detecting unit is not limited to a particular one, and various types of
known sensors may be used if the thickness and the brightness of yarn
5 Y can be detected.
[0045] The device body 81 thus configured includes a detection
module and a case configured to accommodate the detection module as
physical components. The detection module includes a light emitting
element, a first light receiving element, and a second light receiving
10 element, and detects the amount of transmitted light and the amount of
reflected light of light emitted toward yarn Y. In the detection
module, light is emitted (projected) from the light emitting element
toward yarn Y traveling between the air-jet spinning device 7 and the
yarn storage device 11. In the detection module, light (transmitted
15 light) of the light, part of which has been blocked by the yarn Y, is
received by the first light receiving element. In the detection module,
reflected light of the light, which has been reflected by the yarn Y, is
received by the second light receiving element. In the detection
module, a signal indicating the amount of received light (the amount of
20 transmitted light) of the transmitted light received by the first light
receiving element is output as a signal for the thickness of the yarn Y to
the discrimination section 82. In the detection module, a signal
indicating the amount of received light (the amount of reflected light)
of the reflected light received by the second light receiving element is
25 output as a signal for the brightness of the light reflected by the yarn Y
to the discrimination section 82.
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[0046] The light emitting element, the first light receiving element, and
the second light receiving element may be disposed in the same
position in the yarn traveling direction. By this configuration, the
amount of transmitted light and the amount of reflected light related to
5 the same portion of yarn Y can be acquired at the same timing. The
first light receiving element and the second light receiving element may
be disposed in positions different in the yarn traveling direction. Even
in this configuration, the amount of transmitted light and the amount of
reflected light related to the same portion of the yarn Y can be acquired
10 at the same timing. The first light receiving element and the second
light receiving element may include light emitting elements
individually. Specifically, as the light emitting elements, a first light
emitting element and a second light emitting element may be included.
The first light receiving element receives light (transmitted light) that
15 has been emitted by the first light emitting element and part of which
has been blocked by the yarn Y. The second light receiving element
receives reflected light that has been emitted from the second light
emitting element and has been reflected by the yarn Y. The first light
emitting element and the second light emitting element may be
20 disposed in the same position in the yarn traveling direction, or may be
disposed in different positions therein. The first light emitting
element and the first light receiving element may be disposed in the
same position in the yarn traveling direction, the second light emitting
element and the second light receiving element may be disposed in the
25 same position in the yarn traveling direction, and also the position of
the first light emitting element and the first light receiving element in
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the yarn traveling direction may be different from the position of the
second light emitting element and the second light receiving element in
the yarn traveling direction. Even in this configuration, based on the
yarn traveling speed and the separation distance between the first light
5 receiving element and the second light receiving element in the yarn
traveling direction, the amount of transmitted light and the amount of
reflected light related to the same portion of the yarn Y can be
associated with each other.
[0047] One example of physical components of the device body 81
10 will be described with reference to FIG. 3. As illustrated in FIG. 3, the
device body 81 includes a holder 111, a first light projector (light
emitting element) 121, a second light projector (light emitting element)
123, a first light receiver (first light receiving element) 131, and a
second light receiver (second light receiving element) 135.
15 [0048] The holder 111 is configured as a resin housing, to which the
first light projector 121, the second light projector 123, the first light
receiver 131, and the second light receiver 135 are mounted. In the
holder 111, a yarn passage 113 as a detection space including a portion
serving as a yarn path along which yarn Y travels is formed along the
20 traveling direction of the yarn Y. This yarn passage 113 has a shape
that is open to the front side of the device.
[0049] The yarn passage 113 has a first surface 113A, a second surface
113B, and a third surface 113C. The first surface 113A and the third
surface 113C are side wall surfaces on the right and left of the yarn
25 passage 113. The second surface 113B is a deep wall surface of the
yarn passage 113.

We claim:
1. A yarn monitoring device configured to monitor yarn traveling,
the yarn monitoring device comprising:
a discrimination section configured to discriminate a type of a
5 yarn defect of the yarn, based on a combination of thickness of the yarn
and brightness of reflected light that has been reflected by the yarn
when the yarn has been irradiated with light.
2. The yarn monitoring device according to claim 1, wherein the
discrimination section discriminates, as the yarn defect, a first yarn
10 defect having warpage, tangle, or entanglement protruding in a
direction intersecting a direction in which the yarn travels.
3. The yarn monitoring device according to claim 1 or 2, wherein
the discrimination section discriminates, as the yarn defect, a second
yarn defect being a nep into which a foreign substance is mixed.
15 4. The yarn monitoring device according to any one of claims 1 to
3, wherein
the discrimination section includes a first
defect-discrimination-target identification section and a second
defect-discrimination-target identification section,
20 the first defect-discrimination-target identification section
identifies, in a first variation signal for thickness, a first
defect-discrimination-target portion for which a defect is to be
assessed,
the second defect-discrimination-target identification section
25 identifies, in a second variation signal for brightness, a second
defect-discrimination-target portion for which a defect is to be
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assessed, and
the discrimination section identifies the first
defect-discrimination-target portion and the second
defect-discrimination-target portion that correspond to each other in a
5 longitudinal direction of the yarn, and discriminates the type of the
yarn defect based on the thickness of the first
defect-discrimination-target portion and the brightness of the second
defect-discrimination-target portion that have been identified as
portions corresponding to each other.
10 5. The yarn monitoring device according to claim 4, wherein the
discrimination section determines that a first yarn defect having
warpage, tangle, or entanglement protruding in a direction intersecting
a direction in which the yarn travels is present when the thickness of
the first defect-discrimination-target portion is equal to or greater than
15 a first thickness criterion value and the brightness of the second
defect-discrimination-target portion is equal to or higher than a first
brightness criterion value.
6. The yarn monitoring device according to claim 5, wherein the
second defect-discrimination-target portion includes a continuous
20 portion in which the brightness is equal or higher than a threshold in
the yarn, the continuous portion coinciding with at least part of the first
defect-discrimination-target portion.
7. The yarn monitoring device according to claim 4, wherein the
discrimination section determines that a second yarn defect being a nep
25 into which a foreign substance is mixed is present when the thickness
of the first defect-discrimination-target portion is equal to or greater
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than a second thickness criterion value and the brightness of the second
defect-discrimination-target portion is equal to or lower than a second
brightness criterion value.
8. The yarn monitoring device according to claim 7, wherein the
5 second defect-discrimination-target portion includes a continuous
portion in which the brightness is equal to or lower than a threshold in
the yarn, the continuous portion coinciding with at least part of the first
defect-discrimination-target portion.
9. The yarn monitoring device according to any one of claims 1 to
10 8, wherein the discrimination section determines the presence or
absence of a nep into which no foreign substance is mixed, based on
the length of a continuous portion in which the thickness is equal to or
greater than a threshold in the yarn and the thickness of the continuous
portion.
15 10. The yarn monitoring device according to any one of claims 1 to
9, wherein the discrimination section determines the presence or
absence of mixing of a foreign substance, based on the length of a
continuous portion in which the brightness is equal to or lower than a
threshold in the yarn and the brightness of the continuous portion.
20 11. The yarn monitoring device according to any one of claims 1 to
10, further comprising:
a light emitting element configured to emit light toward a
traveling region in which the yarn travels;
a first light receiving element disposed so as to receive light
25 that has been emitted from the light emitting element and part of which
has been blocked by the yarn; and
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a second light receiving element disposed so as to receive light
that has been emitted from the light emitting element and has been
reflected by the yarn, wherein
the thickness is calculated based on the amount of light
5 received by the first light receiving element, and
the brightness is calculated based on the amount of light
received by the second light receiving element.
12. The yarn monitoring device according to claim 4, 6, or 8,
wherein
10 the first defect-discrimination-target identification section
identifies the first defect-discrimination-target portion based on the first
variation signal and a first threshold,
the second defect-discrimination-target identification section
identifies the second defect-discrimination-target portion based on the
15 second variation signal and a second threshold, and
the discrimination section identifies the first
defect-discrimination-target portion and the second
defect-discrimination-target portion overlapping each other in the
longitudinal direction of the yarn as portions corresponding to each
20 other.
13. The yarn monitoring device according to claim 12, wherein
the discrimination section identifies a peak position of the first
defect-discrimination-target portion,
the discrimination section identifies a peak position of the
25 second defect-discrimination-target portion, and
the discrimination section identifies, as the portions
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corresponding to each other, the first defect-discrimination-target
portion and the second defect-discrimination-target portion the peak
positions of which fall within a predetermined range in the longitudinal
direction.
5 14. The yarn monitoring device according to any one of claims 1 to
13, further comprising a display section configured to display a
discrimination result of the discrimination section with a scatter
diagram axes of which represent the thickness and the brightness.
15. The yarn monitoring device according to claim 14, wherein the
10 display section displays a first yarn defect having warpage, tangle, or
entanglement protruding in a direction intersecting a direction in which
the yarn travels so as to distinguish the first yarn defect from another
yarn defect.
16. The yarn monitoring device according to claim 15, wherein the
15 display section displays a second yarn defect being a nep into which a
foreign substance is mixed so as to distinguish the second yarn defect
from another yarn defect.
17. A yarn winding machine comprising:
the yarn monitoring device as claimed in any one of claims 1 to
20 16;
a yarn feeder disposed so as to be able to feed the yarn; and
a winding device configured to wind the yarn fed from the yarn
feeder to form a package, wherein
the yarn monitoring device is disposed between the yarn feeder
25 and the winding device.